From 5cad7494dfd92b8c764d14d0ff550e4be533b53e Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Sun, 31 Mar 2024 17:06:33 -0300
Subject: [PATCH 01/38] fix

---
 vlib/v/gen/c/assert.v |  2 +-
 vlib/v/gen/c/cgen.v   | 87 ++++++++++++++++++++++++++++++++++++-------
 vlib/v/gen/c/fn.v     |  2 +-
 vlib/v/gen/c/match.v  | 12 +++---
 vlib/v/pref/pref.c.v  |  4 ++
 5 files changed, 86 insertions(+), 21 deletions(-)

diff --git a/vlib/v/gen/c/assert.v b/vlib/v/gen/c/assert.v
index 2da73b854128d4..f0801b6894bea0 100644
--- a/vlib/v/gen/c/assert.v
+++ b/vlib/v/gen/c/assert.v
@@ -106,7 +106,7 @@ fn (mut g Gen) assert_subexpression_to_ctemp(expr ast.Expr, expr_type ast.Type)
 }
 
 fn (mut g Gen) gen_assert_postfailure_mode(node ast.AssertStmt) {
-	g.write_v_source_line_info(node.pos)
+	g.write_v_source_line_info_stmt(node)
 	if g.pref.assert_failure_mode == .continues
 		|| g.fn_decl.attrs.any(it.name == 'assert_continues') {
 		return
diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index 7760c061adfed6..0eaa97fd03a964 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -119,6 +119,9 @@ mut:
 	labeled_loops             map[string]&ast.Stmt
 	inner_loop                &ast.Stmt = unsafe { nil }
 	shareds                   map[int]string // types with hidden mutex for which decl has been emitted
+	coverage_files            []&ast.File
+	coverage_total_lines      int
+	coverage_idx              int
 	inside_ternary            int  // ?: comma separated statements on a single line
 	inside_map_postfix        bool // inside map++/-- postfix expr
 	inside_map_infix          bool // inside map<</+=/-= infix expr
@@ -505,6 +508,10 @@ pub fn gen(files []&ast.File, mut table ast.Table, pref_ &pref.Preferences) (str
 		g.write_init_function()
 	}
 
+	if g.pref.is_coverage {
+		g.cheaders.writeln('char _v_cov[${g.coverage_total_lines}] = {0};')
+	}
+
 	// insert for options forward
 	if g.out_options_forward.len > 0 || g.out_results_forward.len > 0 {
 		tail := g.type_definitions.cut_to(g.options_pos_forward)
@@ -2051,7 +2058,7 @@ fn (mut g Gen) expr_with_tmp_var(expr ast.Expr, expr_typ ast.Type, ret_typ ast.T
 }
 
 @[inline]
-fn (mut g Gen) write_v_source_line_info(pos token.Pos) {
+fn (mut g Gen) write_v_source_line_info_pos(pos token.Pos) {
 	if g.inside_ternary == 0 && g.pref.is_vlines && g.is_vlines_enabled {
 		nline := pos.line_nr + 1
 		lineinfo := '\n#line ${nline} "${g.vlines_path}"'
@@ -2062,6 +2069,46 @@ fn (mut g Gen) write_v_source_line_info(pos token.Pos) {
 	}
 }
 
+@[inline]
+fn (mut g Gen) write_v_source_line_info(node ast.Node) {
+	g.write_v_source_line_info_pos(node.pos())
+	if g.inside_ternary == 0 && g.pref.is_coverage
+		&& node !in [ast.MatchBranch, ast.IfBranch, ast.InfixExpr] {
+		if g.file !in g.coverage_files {
+			g.coverage_idx = if g.coverage_files.len == 0 {
+				0
+			} else {
+				g.coverage_total_lines
+			}
+			g.coverage_total_lines += g.file.nr_lines
+			g.coverage_files << g.file
+		}
+		if g.fn_decl != unsafe { nil } {
+			g.writeln('_v_cov[${g.coverage_idx}+${node.pos().line_nr}] = 1;')
+		}
+	}
+}
+
+@[inline]
+fn (mut g Gen) write_v_source_line_info_stmt(stmt ast.Stmt) {
+	g.write_v_source_line_info_pos(stmt.pos)
+	if g.inside_ternary == 0 && g.pref.is_coverage && !g.inside_for_c_stmt
+		&& stmt !in [ast.ExprStmt, ast.FnDecl, ast.ForCStmt, ast.ForInStmt, ast.ForStmt] {
+		if g.file !in g.coverage_files {
+			g.coverage_idx = if g.coverage_files.len == 0 {
+				0
+			} else {
+				g.coverage_total_lines
+			}
+			g.coverage_total_lines += g.file.nr_lines
+			g.coverage_files << g.file
+		}
+		if g.fn_decl != unsafe { nil } {
+			g.writeln('_v_cov[${g.coverage_idx}+${stmt.pos.line_nr}] = \'1\';')
+		}
+	}
+}
+
 fn (mut g Gen) stmt(node ast.Stmt) {
 	$if trace_cgen_stmt ? {
 		ntype := typeof(node).replace('v.ast.', '')
@@ -2077,19 +2124,19 @@ fn (mut g Gen) stmt(node ast.Stmt) {
 	}
 	match node {
 		ast.AsmStmt {
-			g.write_v_source_line_info(node.pos)
+			g.write_v_source_line_info_stmt(node)
 			g.asm_stmt(node)
 		}
 		ast.AssertStmt {
-			g.write_v_source_line_info(node.pos)
+			g.write_v_source_line_info_stmt(node)
 			g.assert_stmt(node)
 		}
 		ast.AssignStmt {
-			g.write_v_source_line_info(node.pos)
+			g.write_v_source_line_info_stmt(node)
 			g.assign_stmt(node)
 		}
 		ast.Block {
-			g.write_v_source_line_info(node.pos)
+			g.write_v_source_line_info_stmt(node)
 			if node.is_unsafe {
 				g.writeln('{ // Unsafe block')
 			} else {
@@ -2099,11 +2146,11 @@ fn (mut g Gen) stmt(node ast.Stmt) {
 			g.writeln('}')
 		}
 		ast.BranchStmt {
-			g.write_v_source_line_info(node.pos)
+			g.write_v_source_line_info_stmt(node)
 			g.branch_stmt(node)
 		}
 		ast.ConstDecl {
-			g.write_v_source_line_info(node.pos)
+			g.write_v_source_line_info_stmt(node)
 			g.const_decl(node)
 		}
 		ast.ComptimeFor {
@@ -2123,7 +2170,7 @@ fn (mut g Gen) stmt(node ast.Stmt) {
 			g.enum_decl(node)
 		}
 		ast.ExprStmt {
-			g.write_v_source_line_info(node.pos)
+			g.write_v_source_line_info_stmt(node)
 			// af := g.autofree && node.expr is ast.CallExpr && !g.is_builtin_mod
 			// if af {
 			// g.autofree_call_pregen(node.expr as ast.CallExpr)
@@ -2163,7 +2210,7 @@ fn (mut g Gen) stmt(node ast.Stmt) {
 					g.labeled_loops[node.label] = &node
 				}
 			}
-			g.write_v_source_line_info(node.pos)
+			g.write_v_source_line_info_stmt(node)
 			g.for_c_stmt(node)
 			g.branch_parent_pos = prev_branch_parent_pos
 			g.labeled_loops.delete(node.label)
@@ -2179,7 +2226,7 @@ fn (mut g Gen) stmt(node ast.Stmt) {
 					g.labeled_loops[node.label] = &node
 				}
 			}
-			g.write_v_source_line_info(node.pos)
+			g.write_v_source_line_info_stmt(node)
 			g.for_in_stmt(node)
 			g.branch_parent_pos = prev_branch_parent_pos
 			g.labeled_loops.delete(node.label)
@@ -2195,7 +2242,7 @@ fn (mut g Gen) stmt(node ast.Stmt) {
 					g.labeled_loops[node.label] = &node
 				}
 			}
-			g.write_v_source_line_info(node.pos)
+			g.write_v_source_line_info_stmt(node)
 			g.for_stmt(node)
 			g.branch_parent_pos = prev_branch_parent_pos
 			g.labeled_loops.delete(node.label)
@@ -2208,7 +2255,7 @@ fn (mut g Gen) stmt(node ast.Stmt) {
 			g.writeln('${c_name(node.name)}: {}')
 		}
 		ast.GotoStmt {
-			g.write_v_source_line_info(node.pos)
+			g.write_v_source_line_info_stmt(node)
 			g.writeln('goto ${c_name(node.name)};')
 		}
 		ast.HashStmt {
@@ -5246,7 +5293,7 @@ fn (mut g Gen) branch_stmt(node ast.BranchStmt) {
 
 fn (mut g Gen) return_stmt(node ast.Return) {
 	g.set_current_pos_as_last_stmt_pos()
-	g.write_v_source_line_info(node.pos)
+	g.write_v_source_line_info_stmt(node)
 
 	g.inside_return = true
 	defer {
@@ -6383,6 +6430,20 @@ fn (mut g Gen) write_init_function() {
 	if g.pref.use_coroutines {
 		g.writeln('\tdelete_photon_work_pool();')
 	}
+	if g.pref.is_coverage {
+		g.writeln('\tprintf("V coverage\\n");')
+		g.writeln('\tprintf("${'-':50r}\\n");')
+		mut last_offset := 0
+		for file in g.coverage_files {
+			g.writeln('{')
+			g.writeln('\tint counter = 0;')
+			g.writeln('\tfor (int i = 0, offset = ${last_offset}; i < ${file.nr_lines}; ++i)')
+			g.writeln('\t\tif (_v_cov[offset+i]) counter++;')
+			g.writeln('\tprintf("> ${file.path} | ${file.nr_lines} | %d\\n", counter);')
+			g.writeln('}')
+			last_offset += file.nr_lines
+		}
+	}
 	g.writeln('}')
 	if g.pref.printfn_list.len > 0 && '_vcleanup' in g.pref.printfn_list {
 		println(g.out.after(fn_vcleanup_start_pos))
diff --git a/vlib/v/gen/c/fn.v b/vlib/v/gen/c/fn.v
index f07bdc0de4618b..1cf7931b510162 100644
--- a/vlib/v/gen/c/fn.v
+++ b/vlib/v/gen/c/fn.v
@@ -212,7 +212,7 @@ fn (mut g Gen) gen_fn_decl(node &ast.FnDecl, skip bool) {
 		g.definitions.writeln(';')
 	}
 
-	g.write_v_source_line_info(node.pos)
+	g.write_v_source_line_info_stmt(node)
 	fn_attrs := g.write_fn_attrs(node.attrs)
 	// Live
 	is_livefn := node.attrs.contains('live')
diff --git a/vlib/v/gen/c/match.v b/vlib/v/gen/c/match.v
index 98883b6c666120..6ffce6eae41995 100644
--- a/vlib/v/gen/c/match.v
+++ b/vlib/v/gen/c/match.v
@@ -183,7 +183,7 @@ fn (mut g Gen) match_expr_sumtype(node ast.MatchExpr, is_expr bool, cond_var str
 					g.write(' : ')
 				} else {
 					g.writeln('')
-					g.write_v_source_line_info(branch.pos)
+					g.write_v_source_line_info(branch)
 					g.writeln('else {')
 				}
 			} else {
@@ -191,7 +191,7 @@ fn (mut g Gen) match_expr_sumtype(node ast.MatchExpr, is_expr bool, cond_var str
 					if use_ternary {
 						g.write(' : ')
 					} else {
-						g.write_v_source_line_info(branch.pos)
+						g.write_v_source_line_info(branch)
 						g.write('else ')
 					}
 				}
@@ -201,7 +201,7 @@ fn (mut g Gen) match_expr_sumtype(node ast.MatchExpr, is_expr bool, cond_var str
 					if j == 0 && sumtype_index == 0 {
 						g.empty_line = true
 					}
-					g.write_v_source_line_info(branch.pos)
+					g.write_v_source_line_info(branch)
 					g.write('if (')
 				}
 				g.write(cond_var)
@@ -428,7 +428,7 @@ fn (mut g Gen) match_expr_classic(node ast.MatchExpr, is_expr bool, cond_var str
 					g.write(' : ')
 				} else {
 					g.writeln('')
-					g.write_v_source_line_info(branch.pos)
+					g.write_v_source_line_info(branch)
 					g.writeln('else {')
 				}
 			}
@@ -438,7 +438,7 @@ fn (mut g Gen) match_expr_classic(node ast.MatchExpr, is_expr bool, cond_var str
 					g.write(' : ')
 				} else {
 					g.writeln('')
-					g.write_v_source_line_info(branch.pos)
+					g.write_v_source_line_info(branch)
 					g.write('else ')
 				}
 			}
@@ -448,7 +448,7 @@ fn (mut g Gen) match_expr_classic(node ast.MatchExpr, is_expr bool, cond_var str
 				if j == 0 {
 					g.writeln('')
 				}
-				g.write_v_source_line_info(branch.pos)
+				g.write_v_source_line_info(branch)
 				g.write('if (')
 			}
 			for i, expr in branch.exprs {
diff --git a/vlib/v/pref/pref.c.v b/vlib/v/pref/pref.c.v
index b720edabf56c46..9527b7051b60e3 100644
--- a/vlib/v/pref/pref.c.v
+++ b/vlib/v/pref/pref.c.v
@@ -134,6 +134,7 @@ pub mut:
 	is_cstrict         bool     // turn on more C warnings; slightly slower
 	is_callstack       bool     // turn on callstack registers on each call when v.debug is imported
 	is_trace           bool     // turn on possibility to trace fn call where v.debug is imported
+	is_coverage        bool     // turn on code coverage stats
 	eval_argument      string   // `println(2+2)` on `v -e "println(2+2)"`. Note that this source code, will be evaluated in vsh mode, so 'v -e 'println(ls(".")!)' is valid.
 	test_runner        string   // can be 'simple' (fastest, but much less detailed), 'tap', 'normal'
 	profile_file       string   // the profile results will be stored inside profile_file
@@ -1084,6 +1085,9 @@ pub fn parse_args_and_show_errors(known_external_commands []string, args []strin
 	if 'trace' in res.compile_defines_all {
 		res.is_trace = true
 	}
+	if 'coverage' in res.compile_defines_all {
+		res.is_coverage = true
+	}
 	// keep only the unique res.build_options:
 	mut m := map[string]string{}
 	for x in res.build_options {

From c25591411e6796fe58e57555208621ae244b5f8b Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Mon, 1 Apr 2024 09:49:28 -0300
Subject: [PATCH 02/38] fix

---
 vlib/v/gen/c/cgen.v  | 84 +++++++++++++++++++++++++++-----------------
 vlib/v/pref/pref.c.v | 10 ++++--
 2 files changed, 58 insertions(+), 36 deletions(-)

diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index 0eaa97fd03a964..a6769e7641d686 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -42,6 +42,15 @@ fn string_array_to_map(a []string) map[string]bool {
 	return res
 }
 
+// V coverage info
+@[heap]
+struct CoverageInfo {
+pub mut:
+	idx    int   // index
+	points []u64 // code point line nr
+	file   &ast.File = unsafe { nil }
+}
+
 pub struct Gen {
 	pref                &pref.Preferences = unsafe { nil }
 	field_data_type     ast.Type // cache her to avoid map lookups
@@ -119,9 +128,7 @@ mut:
 	labeled_loops             map[string]&ast.Stmt
 	inner_loop                &ast.Stmt = unsafe { nil }
 	shareds                   map[int]string // types with hidden mutex for which decl has been emitted
-	coverage_files            []&ast.File
-	coverage_total_lines      int
-	coverage_idx              int
+	coverage_files            map[u64]&CoverageInfo
 	inside_ternary            int  // ?: comma separated statements on a single line
 	inside_map_postfix        bool // inside map++/-- postfix expr
 	inside_map_infix          bool // inside map<</+=/-= infix expr
@@ -414,6 +421,9 @@ pub fn gen(files []&ast.File, mut table ast.Table, pref_ &pref.Preferences) (str
 			for k, v in g.sumtype_definitions {
 				global_g.sumtype_definitions[k] = v
 			}
+			for k, v in g.coverage_files {
+				global_g.coverage_files[k] = v
+			}
 			global_g.json_forward_decls.write(g.json_forward_decls) or { panic(err) }
 			global_g.enum_typedefs.write(g.enum_typedefs) or { panic(err) }
 			global_g.channel_definitions.write(g.channel_definitions) or { panic(err) }
@@ -509,7 +519,12 @@ pub fn gen(files []&ast.File, mut table ast.Table, pref_ &pref.Preferences) (str
 	}
 
 	if g.pref.is_coverage {
-		g.cheaders.writeln('char _v_cov[${g.coverage_total_lines}] = {0};')
+		mut total_code_points := 0
+		for k, cov in g.coverage_files {
+			g.cheaders.writeln('#define _v_cov_file_offset_${k} ${total_code_points}')
+			total_code_points += cov.points.len
+		}
+		g.cheaders.writeln('char _v_cov[${total_code_points}] = {0};')
 	}
 
 	// insert for options forward
@@ -2069,23 +2084,30 @@ fn (mut g Gen) write_v_source_line_info_pos(pos token.Pos) {
 	}
 }
 
+@[inline]
+fn (mut g Gen) write_coverage_point(pos token.Pos) {
+	if g.unique_file_path_hash !in g.coverage_files {
+		g.coverage_files[g.unique_file_path_hash] = &CoverageInfo{
+			points: []
+			file: g.file
+		}
+	}
+	if g.fn_decl != unsafe { nil } {
+		curr_line := u64(pos.line_nr)
+		mut curr_cov := unsafe { g.coverage_files[g.unique_file_path_hash] }
+		if curr_line !in curr_cov.points {
+			curr_cov.points << curr_line
+		}
+		g.writeln('_v_cov[_v_cov_file_offset_${g.unique_file_path_hash}+${curr_cov.points.len - 1}] = 1;')
+	}
+}
+
 @[inline]
 fn (mut g Gen) write_v_source_line_info(node ast.Node) {
 	g.write_v_source_line_info_pos(node.pos())
 	if g.inside_ternary == 0 && g.pref.is_coverage
 		&& node !in [ast.MatchBranch, ast.IfBranch, ast.InfixExpr] {
-		if g.file !in g.coverage_files {
-			g.coverage_idx = if g.coverage_files.len == 0 {
-				0
-			} else {
-				g.coverage_total_lines
-			}
-			g.coverage_total_lines += g.file.nr_lines
-			g.coverage_files << g.file
-		}
-		if g.fn_decl != unsafe { nil } {
-			g.writeln('_v_cov[${g.coverage_idx}+${node.pos().line_nr}] = 1;')
-		}
+		g.write_coverage_point(node.pos())
 	}
 }
 
@@ -2094,18 +2116,7 @@ fn (mut g Gen) write_v_source_line_info_stmt(stmt ast.Stmt) {
 	g.write_v_source_line_info_pos(stmt.pos)
 	if g.inside_ternary == 0 && g.pref.is_coverage && !g.inside_for_c_stmt
 		&& stmt !in [ast.ExprStmt, ast.FnDecl, ast.ForCStmt, ast.ForInStmt, ast.ForStmt] {
-		if g.file !in g.coverage_files {
-			g.coverage_idx = if g.coverage_files.len == 0 {
-				0
-			} else {
-				g.coverage_total_lines
-			}
-			g.coverage_total_lines += g.file.nr_lines
-			g.coverage_files << g.file
-		}
-		if g.fn_decl != unsafe { nil } {
-			g.writeln('_v_cov[${g.coverage_idx}+${stmt.pos.line_nr}] = \'1\';')
-		}
+		g.write_coverage_point(stmt.pos)
 	}
 }
 
@@ -6433,16 +6444,23 @@ fn (mut g Gen) write_init_function() {
 	if g.pref.is_coverage {
 		g.writeln('\tprintf("V coverage\\n");')
 		g.writeln('\tprintf("${'-':50r}\\n");')
+		g.writeln('int t_counter = 0;')
 		mut last_offset := 0
-		for file in g.coverage_files {
+		mut t_points := 0
+		for k, cov in g.coverage_files {
+			nr_points := cov.points.len
+			t_points += nr_points
 			g.writeln('{')
 			g.writeln('\tint counter = 0;')
-			g.writeln('\tfor (int i = 0, offset = ${last_offset}; i < ${file.nr_lines}; ++i)')
-			g.writeln('\t\tif (_v_cov[offset+i]) counter++;')
-			g.writeln('\tprintf("> ${file.path} | ${file.nr_lines} | %d\\n", counter);')
+			g.writeln('\tfor (int i = 0, offset = ${last_offset}; i < ${nr_points}; ++i)')
+			g.writeln('\t\tif (_v_cov[_v_cov_file_offset_${k}+i]) counter++;')
+			g.writeln('\tt_counter += counter;')
+			g.writeln('\tprintf("> ${cov.file.path} | ${nr_points} | %d | %.2f% \\n", counter, ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0);')
 			g.writeln('}')
-			last_offset += file.nr_lines
+			last_offset += nr_points
 		}
+		g.writeln('\tprintf("${'-':50r}\\n");')
+		g.writeln('\tprintf("Total coverage: ${g.coverage_files.len} files, %.2f%% coverage\\n", ((double)t_counter/${t_points})*100);')
 	}
 	g.writeln('}')
 	if g.pref.printfn_list.len > 0 && '_vcleanup' in g.pref.printfn_list {
diff --git a/vlib/v/pref/pref.c.v b/vlib/v/pref/pref.c.v
index 9527b7051b60e3..28edc5c02a8f60 100644
--- a/vlib/v/pref/pref.c.v
+++ b/vlib/v/pref/pref.c.v
@@ -138,6 +138,7 @@ pub mut:
 	eval_argument      string   // `println(2+2)` on `v -e "println(2+2)"`. Note that this source code, will be evaluated in vsh mode, so 'v -e 'println(ls(".")!)' is valid.
 	test_runner        string   // can be 'simple' (fastest, but much less detailed), 'tap', 'normal'
 	profile_file       string   // the profile results will be stored inside profile_file
+	coverage_file      string   // the coverage results will be stored inside coverage_file
 	profile_no_inline  bool     // when true, [inline] functions would not be profiled
 	profile_fns        []string // when set, profiling will be off by default, but inside these functions (and what they call) it will be on.
 	translated         bool     // `v translate doom.v` are we running V code translated from C? allow globals, ++ expressions, etc
@@ -617,6 +618,12 @@ pub fn parse_args_and_show_errors(known_external_commands []string, args []strin
 				res.build_options << '${arg} ${res.profile_file}'
 				i++
 			}
+			'-cov', '-coverage' {
+				// res.coverage_file = cmdline.option(current_args, arg, '-')
+				res.is_coverage = true
+				// res.build_options << '${arg} ${res.profile_file}'
+				// i++
+			}
 			'-profile-fns' {
 				profile_fns := cmdline.option(current_args, arg, '').split(',')
 				if profile_fns.len > 0 {
@@ -1085,9 +1092,6 @@ pub fn parse_args_and_show_errors(known_external_commands []string, args []strin
 	if 'trace' in res.compile_defines_all {
 		res.is_trace = true
 	}
-	if 'coverage' in res.compile_defines_all {
-		res.is_coverage = true
-	}
 	// keep only the unique res.build_options:
 	mut m := map[string]string{}
 	for x in res.build_options {

From f9ed550c4aacdc9d8f89a756ca8221c36a7fd87b Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Mon, 1 Apr 2024 10:35:56 -0300
Subject: [PATCH 03/38] improvement

---
 vlib/v/gen/c/cgen.v     | 48 +++++++----------------------
 vlib/v/gen/c/coverage.v | 67 +++++++++++++++++++++++++++++++++++++++++
 vlib/v/pref/pref.c.v    |  6 ++--
 3 files changed, 81 insertions(+), 40 deletions(-)
 create mode 100644 vlib/v/gen/c/coverage.v

diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index a6769e7641d686..c3a5cdc7366e69 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -78,6 +78,7 @@ mut:
 	auto_str_funcs            strings.Builder // function bodies of all auto generated _str funcs
 	dump_funcs                strings.Builder // function bodies of all auto generated _str funcs
 	pcs_declarations          strings.Builder // -prof profile counter declarations for each function
+	cov_declarations          strings.Builder // -cov coverage
 	embedded_data             strings.Builder // data to embed in the executable/binary
 	shared_types              strings.Builder // shared/lock types
 	shared_functions          strings.Builder // shared constructors
@@ -309,6 +310,7 @@ pub fn gen(files []&ast.File, mut table ast.Table, pref_ &pref.Preferences) (str
 		auto_str_funcs: strings.new_builder(100)
 		dump_funcs: strings.new_builder(100)
 		pcs_declarations: strings.new_builder(100)
+		cov_declarations: strings.new_builder(100)
 		embedded_data: strings.new_builder(1000)
 		out_options_forward: strings.new_builder(100)
 		out_options: strings.new_builder(100)
@@ -389,6 +391,7 @@ pub fn gen(files []&ast.File, mut table ast.Table, pref_ &pref.Preferences) (str
 			global_g.dump_funcs.write(g.auto_str_funcs) or { panic(err) }
 			global_g.comptime_definitions.write(g.comptime_definitions) or { panic(err) }
 			global_g.pcs_declarations.write(g.pcs_declarations) or { panic(err) }
+			global_g.cov_declarations.write(g.cov_declarations) or { panic(err) }
 			global_g.hotcode_definitions.write(g.hotcode_definitions) or { panic(err) }
 			global_g.embedded_data.write(g.embedded_data) or { panic(err) }
 			global_g.shared_types.write(g.shared_types) or { panic(err) }
@@ -562,6 +565,10 @@ pub fn gen(files []&ast.File, mut table ast.Table, pref_ &pref.Preferences) (str
 		b.writeln('\n// V profile counters:')
 		b.write_string(g.pcs_declarations.str())
 	}
+	if g.pref.is_coverage {
+		b.writeln('\n// V coverage:')
+		b.write_string(g.cov_declarations.str())
+	}
 	b.writeln('\n// V includes:')
 	b.write_string(g.includes.str())
 	b.writeln('\n// Enum definitions:')
@@ -676,6 +683,7 @@ fn cgen_process_one_file_cb(mut p pool.PoolProcessor, idx int, wid int) &Gen {
 		auto_str_funcs: strings.new_builder(100)
 		comptime_definitions: strings.new_builder(100)
 		pcs_declarations: strings.new_builder(100)
+		cov_declarations: strings.new_builder(100)
 		hotcode_definitions: strings.new_builder(100)
 		embedded_data: strings.new_builder(1000)
 		out_options_forward: strings.new_builder(100)
@@ -746,6 +754,7 @@ pub fn (mut g Gen) free_builders() {
 		g.dump_funcs.free()
 		g.comptime_definitions.free()
 		g.pcs_declarations.free()
+		g.cov_declarations.free()
 		g.hotcode_definitions.free()
 		g.embedded_data.free()
 		g.shared_types.free()
@@ -2084,24 +2093,6 @@ fn (mut g Gen) write_v_source_line_info_pos(pos token.Pos) {
 	}
 }
 
-@[inline]
-fn (mut g Gen) write_coverage_point(pos token.Pos) {
-	if g.unique_file_path_hash !in g.coverage_files {
-		g.coverage_files[g.unique_file_path_hash] = &CoverageInfo{
-			points: []
-			file: g.file
-		}
-	}
-	if g.fn_decl != unsafe { nil } {
-		curr_line := u64(pos.line_nr)
-		mut curr_cov := unsafe { g.coverage_files[g.unique_file_path_hash] }
-		if curr_line !in curr_cov.points {
-			curr_cov.points << curr_line
-		}
-		g.writeln('_v_cov[_v_cov_file_offset_${g.unique_file_path_hash}+${curr_cov.points.len - 1}] = 1;')
-	}
-}
-
 @[inline]
 fn (mut g Gen) write_v_source_line_info(node ast.Node) {
 	g.write_v_source_line_info_pos(node.pos())
@@ -6442,25 +6433,8 @@ fn (mut g Gen) write_init_function() {
 		g.writeln('\tdelete_photon_work_pool();')
 	}
 	if g.pref.is_coverage {
-		g.writeln('\tprintf("V coverage\\n");')
-		g.writeln('\tprintf("${'-':50r}\\n");')
-		g.writeln('int t_counter = 0;')
-		mut last_offset := 0
-		mut t_points := 0
-		for k, cov in g.coverage_files {
-			nr_points := cov.points.len
-			t_points += nr_points
-			g.writeln('{')
-			g.writeln('\tint counter = 0;')
-			g.writeln('\tfor (int i = 0, offset = ${last_offset}; i < ${nr_points}; ++i)')
-			g.writeln('\t\tif (_v_cov[_v_cov_file_offset_${k}+i]) counter++;')
-			g.writeln('\tt_counter += counter;')
-			g.writeln('\tprintf("> ${cov.file.path} | ${nr_points} | %d | %.2f% \\n", counter, ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0);')
-			g.writeln('}')
-			last_offset += nr_points
-		}
-		g.writeln('\tprintf("${'-':50r}\\n");')
-		g.writeln('\tprintf("Total coverage: ${g.coverage_files.len} files, %.2f%% coverage\\n", ((double)t_counter/${t_points})*100);')
+		g.write_coverage_stats()
+		g.writeln('\tvprint_coverage_stats();')
 	}
 	g.writeln('}')
 	if g.pref.printfn_list.len > 0 && '_vcleanup' in g.pref.printfn_list {
diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
new file mode 100644
index 00000000000000..6a7a7a54416c24
--- /dev/null
+++ b/vlib/v/gen/c/coverage.v
@@ -0,0 +1,67 @@
+// Copyright (c) 2019-2024 Alexander Medvednikov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+module c
+
+import v.token
+
+@[inline]
+fn (mut g Gen) write_coverage_point(pos token.Pos) {
+	if g.unique_file_path_hash !in g.coverage_files {
+		g.coverage_files[g.unique_file_path_hash] = &CoverageInfo{
+			points: []
+			file: g.file
+		}
+	}
+	if g.fn_decl != unsafe { nil } {
+		curr_line := u64(pos.line_nr)
+		mut curr_cov := unsafe { g.coverage_files[g.unique_file_path_hash] }
+		if curr_line !in curr_cov.points {
+			curr_cov.points << curr_line
+		}
+		g.writeln('_v_cov[_v_cov_file_offset_${g.unique_file_path_hash}+${curr_cov.points.len - 1}] = 1;')
+	}
+}
+
+fn (mut g Gen) write_coverage_stats() {
+	is_stdout := g.pref.coverage_file == '-'
+
+	g.cov_declarations.writeln('void vprint_coverage_stats() {')
+	if is_stdout {
+		g.cov_declarations.writeln('\tprintf("V coverage\\n");')
+		g.cov_declarations.writeln('\tprintf("${'-':50r}\\n");')
+	} else {
+		g.cov_declarations.writeln('FILE *fp = stdout;')
+		g.cov_declarations.writeln('fp = fopen ("${g.pref.coverage_file}", "w+");')
+		g.cov_declarations.writeln('\tfprintf(fp, "V coverage\\n");')
+		g.cov_declarations.writeln('\tfprintf(fp, "${'-':50r}\\n");')
+	}
+	g.cov_declarations.writeln('int t_counter = 0;')
+	mut last_offset := 0
+	mut t_points := 0
+	for k, cov in g.coverage_files {
+		nr_points := cov.points.len
+		t_points += nr_points
+		g.cov_declarations.writeln('{')
+		g.cov_declarations.writeln('\tint counter = 0;')
+		g.cov_declarations.writeln('\tfor (int i = 0, offset = ${last_offset}; i < ${nr_points}; ++i)')
+		g.cov_declarations.writeln('\t\tif (_v_cov[_v_cov_file_offset_${k}+i]) counter++;')
+		g.cov_declarations.writeln('\tt_counter += counter;')
+		if is_stdout {
+			g.cov_declarations.writeln('\tprintf("> ${cov.file.path} | ${nr_points} | %d | %.2f% \\n", counter, ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0);')
+		} else {
+			g.cov_declarations.writeln('\tfprintf(fp, "> ${cov.file.path} | ${nr_points} | %d | %.2f% \\n", counter, ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0);')
+		}
+		g.cov_declarations.writeln('}')
+		last_offset += nr_points
+	}
+	if is_stdout {
+		g.cov_declarations.writeln('\tprintf("${'-':50r}\\n");')
+		g.cov_declarations.writeln('\tprintf("Total coverage: ${g.coverage_files.len} files, %.2f%% coverage\\n", ((double)t_counter/${t_points})*100);')
+	} else {
+		g.cov_declarations.writeln('\tfprintf(fp, "${'-':50r}\\n");')
+		g.cov_declarations.writeln('\tfprintf(fp, "Total coverage: ${g.coverage_files.len} files, %.2f%% coverage\\n", ((double)t_counter/${t_points})*100);')
+		g.cov_declarations.writeln('\tfclose(fp);')
+	}
+	g.cov_declarations.writeln('}')
+}
diff --git a/vlib/v/pref/pref.c.v b/vlib/v/pref/pref.c.v
index 28edc5c02a8f60..d5a46c94598282 100644
--- a/vlib/v/pref/pref.c.v
+++ b/vlib/v/pref/pref.c.v
@@ -619,10 +619,10 @@ pub fn parse_args_and_show_errors(known_external_commands []string, args []strin
 				i++
 			}
 			'-cov', '-coverage' {
-				// res.coverage_file = cmdline.option(current_args, arg, '-')
+				res.coverage_file = cmdline.option(current_args, arg, '-')
 				res.is_coverage = true
-				// res.build_options << '${arg} ${res.profile_file}'
-				// i++
+				res.build_options << '${arg} ${res.coverage_file}'
+				i++
 			}
 			'-profile-fns' {
 				profile_fns := cmdline.option(current_args, arg, '').split(',')

From a1c524c93d6d0fe0bf7a9ada117151e65c49a6e9 Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Mon, 1 Apr 2024 11:33:54 -0300
Subject: [PATCH 04/38] fix

---
 vlib/v/gen/c/coverage.v | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 6a7a7a54416c24..e25ed7b0648fca 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -1,4 +1,4 @@
-// Copyright (c) 2019-2024 Alexander Medvednikov. All rights reserved.
+// Copyright (c) 2024 Felipe Pena. All rights reserved.
 // Use of this source code is governed by an MIT license
 // that can be found in the LICENSE file.
 module c
@@ -31,28 +31,28 @@ fn (mut g Gen) write_coverage_stats() {
 		g.cov_declarations.writeln('\tprintf("V coverage\\n");')
 		g.cov_declarations.writeln('\tprintf("${'-':50r}\\n");')
 	} else {
-		g.cov_declarations.writeln('FILE *fp = stdout;')
-		g.cov_declarations.writeln('fp = fopen ("${g.pref.coverage_file}", "w+");')
+		g.cov_declarations.writeln('\tFILE *fp = stdout;')
+		g.cov_declarations.writeln('\tfp = fopen ("${g.pref.coverage_file}", "w+");')
 		g.cov_declarations.writeln('\tfprintf(fp, "V coverage\\n");')
 		g.cov_declarations.writeln('\tfprintf(fp, "${'-':50r}\\n");')
 	}
-	g.cov_declarations.writeln('int t_counter = 0;')
+	g.cov_declarations.writeln('\tint t_counter = 0;')
 	mut last_offset := 0
 	mut t_points := 0
 	for k, cov in g.coverage_files {
 		nr_points := cov.points.len
 		t_points += nr_points
-		g.cov_declarations.writeln('{')
-		g.cov_declarations.writeln('\tint counter = 0;')
-		g.cov_declarations.writeln('\tfor (int i = 0, offset = ${last_offset}; i < ${nr_points}; ++i)')
-		g.cov_declarations.writeln('\t\tif (_v_cov[_v_cov_file_offset_${k}+i]) counter++;')
-		g.cov_declarations.writeln('\tt_counter += counter;')
+		g.cov_declarations.writeln('\t{')
+		g.cov_declarations.writeln('\t\tint counter = 0;')
+		g.cov_declarations.writeln('\t\tfor (int i = 0, offset = ${last_offset}; i < ${nr_points}; ++i)')
+		g.cov_declarations.writeln('\t\t\tif (_v_cov[_v_cov_file_offset_${k}+i]) counter++;')
+		g.cov_declarations.writeln('\t\tt_counter += counter;')
 		if is_stdout {
-			g.cov_declarations.writeln('\tprintf("> ${cov.file.path} | ${nr_points} | %d | %.2f% \\n", counter, ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0);')
+			g.cov_declarations.writeln('\t\tprintf("> ${cov.file.path} | ${nr_points} | %d | %.2f%% \\n", counter, ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0);')
 		} else {
-			g.cov_declarations.writeln('\tfprintf(fp, "> ${cov.file.path} | ${nr_points} | %d | %.2f% \\n", counter, ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0);')
+			g.cov_declarations.writeln('\t\tfprintf(fp, "> ${cov.file.path} | ${nr_points} | %d | %.2f%% \\n", counter, ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0);')
 		}
-		g.cov_declarations.writeln('}')
+		g.cov_declarations.writeln('\t}')
 		last_offset += nr_points
 	}
 	if is_stdout {

From 68bd90d9fe0ed395138bd192b0d36d5e2923c3ae Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Mon, 1 Apr 2024 11:41:47 -0300
Subject: [PATCH 05/38] improvement

---
 vlib/v/gen/c/coverage.v | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index e25ed7b0648fca..765ead7afa0d43 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -48,9 +48,9 @@ fn (mut g Gen) write_coverage_stats() {
 		g.cov_declarations.writeln('\t\t\tif (_v_cov[_v_cov_file_offset_${k}+i]) counter++;')
 		g.cov_declarations.writeln('\t\tt_counter += counter;')
 		if is_stdout {
-			g.cov_declarations.writeln('\t\tprintf("> ${cov.file.path} | ${nr_points} | %d | %.2f%% \\n", counter, ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0);')
+			g.cov_declarations.writeln('\t\tprintf("[%7.2f%%] %4d / ${nr_points:4d} | ${cov.file.path}\\n", ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0, counter);')
 		} else {
-			g.cov_declarations.writeln('\t\tfprintf(fp, "> ${cov.file.path} | ${nr_points} | %d | %.2f%% \\n", counter, ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0);')
+			g.cov_declarations.writeln('\t\tfprintf(fp, "[%7.2f%%] %4d / ${nr_points:4d} | ${cov.file.path}\\n", ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0, counter);')
 		}
 		g.cov_declarations.writeln('\t}')
 		last_offset += nr_points

From f05811a45d6ab018667ccaddbf67570669b1e955 Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Mon, 13 May 2024 20:38:23 -0300
Subject: [PATCH 06/38] improve

---
 vlib/v/gen/c/cgen.v | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index c3a5cdc7366e69..a17e42e357904b 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -2106,8 +2106,15 @@ fn (mut g Gen) write_v_source_line_info(node ast.Node) {
 fn (mut g Gen) write_v_source_line_info_stmt(stmt ast.Stmt) {
 	g.write_v_source_line_info_pos(stmt.pos)
 	if g.inside_ternary == 0 && g.pref.is_coverage && !g.inside_for_c_stmt
-		&& stmt !in [ast.ExprStmt, ast.FnDecl, ast.ForCStmt, ast.ForInStmt, ast.ForStmt] {
-		g.write_coverage_point(stmt.pos)
+		&& stmt !in [ast.FnDecl, ast.ForCStmt, ast.ForInStmt, ast.ForStmt] {
+		if stmt is ast.ExprStmt {
+			if !g.inside_assign
+				&& stmt.expr !in [ast.StringInterLiteral, ast.StringLiteral, ast.Ident] {
+				g.write_coverage_point(stmt.pos)
+			}
+		} else {
+			g.write_coverage_point(stmt.pos)
+		}
 	}
 }
 

From 5a8ecb80509a8bcdd4387914d125573deed49da4 Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Mon, 13 May 2024 20:45:33 -0300
Subject: [PATCH 07/38] fix merge

---
 vlib/v/pref/pref.v | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/vlib/v/pref/pref.v b/vlib/v/pref/pref.v
index 0f29e6372df7eb..53cc08b6bafd8b 100644
--- a/vlib/v/pref/pref.v
+++ b/vlib/v/pref/pref.v
@@ -604,7 +604,7 @@ pub fn parse_args_and_show_errors(known_external_commands []string, args []strin
 				i++
 			}
 			'-cov', '-coverage' {
-				res.coverage_file = cmdline.option(current_args, arg, '-')
+				res.coverage_file = cmdline.option(args[i..], arg, '-')
 				res.is_coverage = true
 				res.build_options << '${arg} ${res.coverage_file}'
 				i++

From 0adcd12c9f248a379814fe7b62b67127942fda9d Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Thu, 23 May 2024 12:14:51 -0300
Subject: [PATCH 08/38] wip

---
 vlib/v/gen/c/cgen.v     |  8 ++++----
 vlib/v/gen/c/coverage.v | 38 +++++++++++++++++++++++++++++++++-----
 2 files changed, 37 insertions(+), 9 deletions(-)

diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index 27a434fcd894d8..eb9f7ed6d9282b 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -565,10 +565,6 @@ pub fn gen(files []&ast.File, mut table ast.Table, pref_ &pref.Preferences) (str
 		b.writeln('\n// V profile counters:')
 		b.write_string(g.pcs_declarations.str())
 	}
-	if g.pref.is_coverage {
-		b.writeln('\n// V coverage:')
-		b.write_string(g.cov_declarations.str())
-	}
 	b.writeln('\n// V includes:')
 	b.write_string(g.includes.str())
 	b.writeln('\n// Enum definitions:')
@@ -645,6 +641,10 @@ pub fn gen(files []&ast.File, mut table ast.Table, pref_ &pref.Preferences) (str
 			b.writeln(fn_def)
 		}
 	}
+	if g.pref.is_coverage {
+		b.writeln('\n// V coverage:')
+		b.write_string(g.cov_declarations.str())
+	}
 	b.writeln('\n// end of V out')
 	mut header := b.last_n(b.len)
 	header = '#ifndef V_HEADER_FILE\n#define V_HEADER_FILE' + header
diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 765ead7afa0d43..3a12ee9cc3b246 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -5,6 +5,21 @@ module c
 
 import v.token
 
+@[inline]
+fn current_time() u64 {
+	unsafe {
+		$if windows {
+			tm := u64(0)
+			C.QueryPerformanceCounter(&tm)
+			return tm
+		} $else {
+			ts := C.timespec{}
+			C.clock_gettime(C.CLOCK_MONOTONIC, &ts)
+			return u64(ts.tv_sec) * 1000000000 + u64(ts.tv_nsec)
+		}
+	}
+}
+
 @[inline]
 fn (mut g Gen) write_coverage_point(pos token.Pos) {
 	if g.unique_file_path_hash !in g.coverage_files {
@@ -24,15 +39,26 @@ fn (mut g Gen) write_coverage_point(pos token.Pos) {
 }
 
 fn (mut g Gen) write_coverage_stats() {
-	is_stdout := g.pref.coverage_file == '-'
+	is_stdout := false // g.pref.coverage_file == '-'
 
+	g.cov_declarations.writeln('char* vcoverage_fnv1a(const u8* data) {')
+	g.cov_declarations.writeln('\tu32 h = 2166136261UL;')
+	g.cov_declarations.writeln('\tsize_t size = strlen(data);')
+	g.cov_declarations.writeln('\tfor (size_t i = 0; i < size; i++) {')
+	g.cov_declarations.writeln('\th ^= data[i];')
+	g.cov_declarations.writeln('\th *= 16777619;')
+	g.cov_declarations.writeln('\t}')
+	g.cov_declarations.writeln('\treturn u32_str(h).str;')
+	g.cov_declarations.writeln('}')
+	g.cov_declarations.writeln('')
 	g.cov_declarations.writeln('void vprint_coverage_stats() {')
 	if is_stdout {
 		g.cov_declarations.writeln('\tprintf("V coverage\\n");')
 		g.cov_declarations.writeln('\tprintf("${'-':50r}\\n");')
 	} else {
-		g.cov_declarations.writeln('\tFILE *fp = stdout;')
-		g.cov_declarations.writeln('\tfp = fopen ("${g.pref.coverage_file}", "w+");')
+		g.cov_declarations.writeln('time_t rawtime;')
+		g.cov_declarations.writeln('time(&rawtime);')
+		g.cov_declarations.writeln('\tFILE *fp = fopen(vcoverage_fnv1a(asctime(localtime(&rawtime))), "w+");')
 		g.cov_declarations.writeln('\tfprintf(fp, "V coverage\\n");')
 		g.cov_declarations.writeln('\tfprintf(fp, "${'-':50r}\\n");')
 	}
@@ -47,11 +73,13 @@ fn (mut g Gen) write_coverage_stats() {
 		g.cov_declarations.writeln('\t\tfor (int i = 0, offset = ${last_offset}; i < ${nr_points}; ++i)')
 		g.cov_declarations.writeln('\t\t\tif (_v_cov[_v_cov_file_offset_${k}+i]) counter++;')
 		g.cov_declarations.writeln('\t\tt_counter += counter;')
+		g.cov_declarations.writeln('\t\tif (counter) {')
 		if is_stdout {
-			g.cov_declarations.writeln('\t\tprintf("[%7.2f%%] %4d / ${nr_points:4d} | ${cov.file.path}\\n", ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0, counter);')
+			g.cov_declarations.writeln('\t\t\tprintf("[%7.2f%%] %4d / ${nr_points:4d} | ${cov.file.path}\\n", ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0, counter);')
 		} else {
-			g.cov_declarations.writeln('\t\tfprintf(fp, "[%7.2f%%] %4d / ${nr_points:4d} | ${cov.file.path}\\n", ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0, counter);')
+			g.cov_declarations.writeln('\t\t\tfprintf(fp, "[%7.2f%%] %4d / ${nr_points:4d} | ${cov.file.path}\\n", ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0, counter);')
 		}
+		g.cov_declarations.writeln('\t\t}')
 		g.cov_declarations.writeln('\t}')
 		last_offset += nr_points
 	}

From b5d9fa699fa77a92fd32804799f501e054ccf618 Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Fri, 24 May 2024 10:06:18 -0300
Subject: [PATCH 09/38] wip

---
 cmd/tools/vcover/vcover.v | 20 ++++++++++++++++++++
 cmd/v/v.v                 |  1 +
 vlib/v/gen/c/cgen.v       |  4 ++--
 vlib/v/gen/c/coverage.v   | 27 ++++++++++++++++++++++++---
 4 files changed, 47 insertions(+), 5 deletions(-)
 create mode 100644 cmd/tools/vcover/vcover.v

diff --git a/cmd/tools/vcover/vcover.v b/cmd/tools/vcover/vcover.v
new file mode 100644
index 00000000000000..e06b9c575db2b4
--- /dev/null
+++ b/cmd/tools/vcover/vcover.v
@@ -0,0 +1,20 @@
+// Copyright (c) 2024 Felipe Pena. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+module main
+
+import os
+import os.cmdline
+
+const tmp_dir = os.join_path(os.vtmp_dir(), 'cover')
+
+fn main() {
+	args := cmdline.options_after(os.args, ['cover'])
+	covdir := os.real_path(cmdline.option(args, '-covdir', ''))
+	reportfile := os.real_path(cmdline.option(args, '-report', ''))
+	mergedir := os.real_path(cmdline.option(args, '-merge', ''))
+
+	dump(covdir)
+	dump(reportfile)
+	dump(mergedir)
+}
diff --git a/cmd/v/v.v b/cmd/v/v.v
index ea8fb7e4926d54..4946696d2dac6d 100644
--- a/cmd/v/v.v
+++ b/cmd/v/v.v
@@ -23,6 +23,7 @@ const external_tools = [
 	'check-md',
 	'complete',
 	'compress',
+	'cover',
 	'doc',
 	'doctor',
 	'fmt',
diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index eb9f7ed6d9282b..ff86fdd0a36cd1 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -2095,7 +2095,7 @@ fn (mut g Gen) write_v_source_line_info_pos(pos token.Pos) {
 fn (mut g Gen) write_v_source_line_info(node ast.Node) {
 	g.write_v_source_line_info_pos(node.pos())
 	if g.inside_ternary == 0 && g.pref.is_coverage
-		&& node !in [ast.MatchBranch, ast.IfBranch, ast.InfixExpr] {
+		&& node !in [ast.MatchBranch, ast.IfBranch, ast.InfixExpr, ast.UnsafeExpr] {
 		g.write_coverage_point(node.pos())
 	}
 }
@@ -2107,7 +2107,7 @@ fn (mut g Gen) write_v_source_line_info_stmt(stmt ast.Stmt) {
 		&& stmt !in [ast.FnDecl, ast.ForCStmt, ast.ForInStmt, ast.ForStmt] {
 		if stmt is ast.ExprStmt {
 			if !g.inside_assign
-				&& stmt.expr !in [ast.StringInterLiteral, ast.StringLiteral, ast.Ident] {
+				&& stmt.expr !in [ast.StringInterLiteral, ast.StringLiteral, ast.Ident, ast.UnsafeExpr] {
 				g.write_coverage_point(stmt.pos)
 			}
 		} else {
diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 3a12ee9cc3b246..3b63a6e4d08af0 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -3,6 +3,7 @@
 // that can be found in the LICENSE file.
 module c
 
+import hash.fnv1a
 import v.token
 
 @[inline]
@@ -40,6 +41,7 @@ fn (mut g Gen) write_coverage_point(pos token.Pos) {
 
 fn (mut g Gen) write_coverage_stats() {
 	is_stdout := false // g.pref.coverage_file == '-'
+	is_json := true
 
 	g.cov_declarations.writeln('char* vcoverage_fnv1a(const u8* data) {')
 	g.cov_declarations.writeln('\tu32 h = 2166136261UL;')
@@ -51,20 +53,32 @@ fn (mut g Gen) write_coverage_stats() {
 	g.cov_declarations.writeln('\treturn u32_str(h).str;')
 	g.cov_declarations.writeln('}')
 	g.cov_declarations.writeln('')
+
+	build_hash := fnv1a.sum64_string(current_time().str())
+
 	g.cov_declarations.writeln('void vprint_coverage_stats() {')
 	if is_stdout {
 		g.cov_declarations.writeln('\tprintf("V coverage\\n");')
 		g.cov_declarations.writeln('\tprintf("${'-':50r}\\n");')
 	} else {
 		g.cov_declarations.writeln('time_t rawtime;')
+		g.cov_declarations.writeln('char cov_filename[200];')
 		g.cov_declarations.writeln('time(&rawtime);')
-		g.cov_declarations.writeln('\tFILE *fp = fopen(vcoverage_fnv1a(asctime(localtime(&rawtime))), "w+");')
-		g.cov_declarations.writeln('\tfprintf(fp, "V coverage\\n");')
-		g.cov_declarations.writeln('\tfprintf(fp, "${'-':50r}\\n");')
+		g.cov_declarations.writeln('snprintf(cov_filename, 200, "vcover.%s.%s", "${build_hash}", vcoverage_fnv1a(asctime(localtime(&rawtime))));')
+
+		g.cov_declarations.writeln('\tFILE *fp = fopen(cov_filename, "w+");')
+
+		if is_json {
+			g.cov_declarations.writeln('\tfprintf(fp, "[");')
+		} else {
+			g.cov_declarations.writeln('\tfprintf(fp, "V coverage\\n");')
+			g.cov_declarations.writeln('\tfprintf(fp, "${'-':50r}\\n");')
+		}
 	}
 	g.cov_declarations.writeln('\tint t_counter = 0;')
 	mut last_offset := 0
 	mut t_points := 0
+	mut is_first := true
 	for k, cov in g.coverage_files {
 		nr_points := cov.points.len
 		t_points += nr_points
@@ -76,6 +90,11 @@ fn (mut g Gen) write_coverage_stats() {
 		g.cov_declarations.writeln('\t\tif (counter) {')
 		if is_stdout {
 			g.cov_declarations.writeln('\t\t\tprintf("[%7.2f%%] %4d / ${nr_points:4d} | ${cov.file.path}\\n", ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0, counter);')
+		} else if is_json {
+			g.cov_declarations.writeln("\t\t\tfprintf(fp, \"%s{\\\"file\\\":\\\"%s\\\",\\\"cov\\\":%.2f,\\\"points\\\":%d}\", ${int(is_first)} ? \"\" : \",\", \"${cov.file.path}\", ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0, ${nr_points});")
+			if is_first {
+				is_first = !is_first
+			}
 		} else {
 			g.cov_declarations.writeln('\t\t\tfprintf(fp, "[%7.2f%%] %4d / ${nr_points:4d} | ${cov.file.path}\\n", ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0, counter);')
 		}
@@ -86,6 +105,8 @@ fn (mut g Gen) write_coverage_stats() {
 	if is_stdout {
 		g.cov_declarations.writeln('\tprintf("${'-':50r}\\n");')
 		g.cov_declarations.writeln('\tprintf("Total coverage: ${g.coverage_files.len} files, %.2f%% coverage\\n", ((double)t_counter/${t_points})*100);')
+	} else if is_json {
+		g.cov_declarations.writeln('\tfprintf(fp, "]");')
 	} else {
 		g.cov_declarations.writeln('\tfprintf(fp, "${'-':50r}\\n");')
 		g.cov_declarations.writeln('\tfprintf(fp, "Total coverage: ${g.coverage_files.len} files, %.2f%% coverage\\n", ((double)t_counter/${t_points})*100);')

From cf6bb6f6fb8e339d5092507c54ca6922f96a9a6a Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Fri, 24 May 2024 10:15:37 -0300
Subject: [PATCH 10/38] fix

---
 vlib/v/gen/c/cgen.v | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index ff86fdd0a36cd1..1acc589f49cd74 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -2095,7 +2095,7 @@ fn (mut g Gen) write_v_source_line_info_pos(pos token.Pos) {
 fn (mut g Gen) write_v_source_line_info(node ast.Node) {
 	g.write_v_source_line_info_pos(node.pos())
 	if g.inside_ternary == 0 && g.pref.is_coverage
-		&& node !in [ast.MatchBranch, ast.IfBranch, ast.InfixExpr, ast.UnsafeExpr] {
+		&& node !in [ast.MatchBranch, ast.IfBranch, ast.InfixExpr] {
 		g.write_coverage_point(node.pos())
 	}
 }

From c223eb93bc63151d81a29e49e11bbb5a3077ff93 Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Fri, 24 May 2024 10:24:25 -0300
Subject: [PATCH 11/38] wip

---
 vlib/v/gen/c/coverage.v | 70 +++++++----------------------------------
 1 file changed, 12 insertions(+), 58 deletions(-)

diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 3b63a6e4d08af0..0519a4b65d844c 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -3,23 +3,8 @@
 // that can be found in the LICENSE file.
 module c
 
-import hash.fnv1a
 import v.token
-
-@[inline]
-fn current_time() u64 {
-	unsafe {
-		$if windows {
-			tm := u64(0)
-			C.QueryPerformanceCounter(&tm)
-			return tm
-		} $else {
-			ts := C.timespec{}
-			C.clock_gettime(C.CLOCK_MONOTONIC, &ts)
-			return u64(ts.tv_sec) * 1000000000 + u64(ts.tv_nsec)
-		}
-	}
-}
+import rand { ulid }
 
 @[inline]
 fn (mut g Gen) write_coverage_point(pos token.Pos) {
@@ -40,9 +25,6 @@ fn (mut g Gen) write_coverage_point(pos token.Pos) {
 }
 
 fn (mut g Gen) write_coverage_stats() {
-	is_stdout := false // g.pref.coverage_file == '-'
-	is_json := true
-
 	g.cov_declarations.writeln('char* vcoverage_fnv1a(const u8* data) {')
 	g.cov_declarations.writeln('\tu32 h = 2166136261UL;')
 	g.cov_declarations.writeln('\tsize_t size = strlen(data);')
@@ -54,63 +36,35 @@ fn (mut g Gen) write_coverage_stats() {
 	g.cov_declarations.writeln('}')
 	g.cov_declarations.writeln('')
 
-	build_hash := fnv1a.sum64_string(current_time().str())
+	build_hash := ulid()
 
 	g.cov_declarations.writeln('void vprint_coverage_stats() {')
-	if is_stdout {
-		g.cov_declarations.writeln('\tprintf("V coverage\\n");')
-		g.cov_declarations.writeln('\tprintf("${'-':50r}\\n");')
-	} else {
-		g.cov_declarations.writeln('time_t rawtime;')
-		g.cov_declarations.writeln('char cov_filename[200];')
-		g.cov_declarations.writeln('time(&rawtime);')
-		g.cov_declarations.writeln('snprintf(cov_filename, 200, "vcover.%s.%s", "${build_hash}", vcoverage_fnv1a(asctime(localtime(&rawtime))));')
-
-		g.cov_declarations.writeln('\tFILE *fp = fopen(cov_filename, "w+");')
 
-		if is_json {
-			g.cov_declarations.writeln('\tfprintf(fp, "[");')
-		} else {
-			g.cov_declarations.writeln('\tfprintf(fp, "V coverage\\n");')
-			g.cov_declarations.writeln('\tfprintf(fp, "${'-':50r}\\n");')
-		}
-	}
+	g.cov_declarations.writeln('time_t rawtime;')
+	g.cov_declarations.writeln('char cov_filename[120];')
+	g.cov_declarations.writeln('time(&rawtime);')
+	g.cov_declarations.writeln('snprintf(cov_filename, 120, "vcover.%s.%s", "${build_hash}", vcoverage_fnv1a(asctime(localtime(&rawtime))));')
+	g.cov_declarations.writeln('\tFILE *fp = fopen(cov_filename, "w+");')
+	g.cov_declarations.writeln('\tfprintf(fp, "[");')
 	g.cov_declarations.writeln('\tint t_counter = 0;')
 	mut last_offset := 0
-	mut t_points := 0
 	mut is_first := true
 	for k, cov in g.coverage_files {
 		nr_points := cov.points.len
-		t_points += nr_points
 		g.cov_declarations.writeln('\t{')
 		g.cov_declarations.writeln('\t\tint counter = 0;')
 		g.cov_declarations.writeln('\t\tfor (int i = 0, offset = ${last_offset}; i < ${nr_points}; ++i)')
 		g.cov_declarations.writeln('\t\t\tif (_v_cov[_v_cov_file_offset_${k}+i]) counter++;')
 		g.cov_declarations.writeln('\t\tt_counter += counter;')
 		g.cov_declarations.writeln('\t\tif (counter) {')
-		if is_stdout {
-			g.cov_declarations.writeln('\t\t\tprintf("[%7.2f%%] %4d / ${nr_points:4d} | ${cov.file.path}\\n", ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0, counter);')
-		} else if is_json {
-			g.cov_declarations.writeln("\t\t\tfprintf(fp, \"%s{\\\"file\\\":\\\"%s\\\",\\\"cov\\\":%.2f,\\\"points\\\":%d}\", ${int(is_first)} ? \"\" : \",\", \"${cov.file.path}\", ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0, ${nr_points});")
-			if is_first {
-				is_first = !is_first
-			}
-		} else {
-			g.cov_declarations.writeln('\t\t\tfprintf(fp, "[%7.2f%%] %4d / ${nr_points:4d} | ${cov.file.path}\\n", ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0, counter);')
+		g.cov_declarations.writeln("\t\t\tfprintf(fp, \"%s{\\\"file\\\":\\\"%s\\\",\\\"cov\\\":%.2f,\\\"points\\\":%d}\", ${int(is_first)} ? \"\" : \",\", \"${cov.file.path}\", ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0, ${nr_points});")
+		if is_first {
+			is_first = !is_first
 		}
 		g.cov_declarations.writeln('\t\t}')
 		g.cov_declarations.writeln('\t}')
 		last_offset += nr_points
 	}
-	if is_stdout {
-		g.cov_declarations.writeln('\tprintf("${'-':50r}\\n");')
-		g.cov_declarations.writeln('\tprintf("Total coverage: ${g.coverage_files.len} files, %.2f%% coverage\\n", ((double)t_counter/${t_points})*100);')
-	} else if is_json {
-		g.cov_declarations.writeln('\tfprintf(fp, "]");')
-	} else {
-		g.cov_declarations.writeln('\tfprintf(fp, "${'-':50r}\\n");')
-		g.cov_declarations.writeln('\tfprintf(fp, "Total coverage: ${g.coverage_files.len} files, %.2f%% coverage\\n", ((double)t_counter/${t_points})*100);')
-		g.cov_declarations.writeln('\tfclose(fp);')
-	}
+	g.cov_declarations.writeln('\tfprintf(fp, "]");')
 	g.cov_declarations.writeln('}')
 }

From 791d7ba4f7b14caaa14d7b81dbcf01eb1ba90340 Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Fri, 24 May 2024 14:57:20 -0300
Subject: [PATCH 12/38] wip

---
 cmd/tools/vcover/vcover.v | 31 +++++++++++++++++++++++++------
 vlib/v/gen/c/coverage.v   |  2 +-
 2 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/cmd/tools/vcover/vcover.v b/cmd/tools/vcover/vcover.v
index e06b9c575db2b4..a2ed4fcdaef2f0 100644
--- a/cmd/tools/vcover/vcover.v
+++ b/cmd/tools/vcover/vcover.v
@@ -3,18 +3,37 @@
 // that can be found in the LICENSE file.
 module main
 
+import json
 import os
 import os.cmdline
+import arrays
 
 const tmp_dir = os.join_path(os.vtmp_dir(), 'cover')
 
+struct VCoverData {
+	file   string // file name
+	hits   u64    // file coverage hits
+	points u64    // file counter
+}
+
+fn report_file(covfile string) ! {
+	json_content := os.read_file(covfile)!
+	data := json.decode([]VCoverData, json_content)!
+	hits := arrays.sum(data.map(it.hits))!
+	points := arrays.sum(data.map(it.points))!
+	for lineinfo in data {
+		println('${(f64(lineinfo.hits) / lineinfo.points) * 100:7.2f} | ${lineinfo.hits:4u} | ${lineinfo.points:4u} | ${lineinfo.file}')
+	}
+	println('Total coverage: ${data.len} files, ${(f64(hits) / points) * 100:.2f}% coverage')
+}
+
 fn main() {
 	args := cmdline.options_after(os.args, ['cover'])
-	covdir := os.real_path(cmdline.option(args, '-covdir', ''))
-	reportfile := os.real_path(cmdline.option(args, '-report', ''))
-	mergedir := os.real_path(cmdline.option(args, '-merge', ''))
+	covfile := os.real_path(cmdline.option(args, '-file', ''))
+	// covdir := os.real_path(cmdline.option(args, '-dir', ''))
+	// reportfile := os.real_path(cmdline.option(args, '-report', ''))
 
-	dump(covdir)
-	dump(reportfile)
-	dump(mergedir)
+	if covfile != '' {
+		report_file(covfile)!
+	}
 }
diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 0519a4b65d844c..3610877394b337 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -57,7 +57,7 @@ fn (mut g Gen) write_coverage_stats() {
 		g.cov_declarations.writeln('\t\t\tif (_v_cov[_v_cov_file_offset_${k}+i]) counter++;')
 		g.cov_declarations.writeln('\t\tt_counter += counter;')
 		g.cov_declarations.writeln('\t\tif (counter) {')
-		g.cov_declarations.writeln("\t\t\tfprintf(fp, \"%s{\\\"file\\\":\\\"%s\\\",\\\"cov\\\":%.2f,\\\"points\\\":%d}\", ${int(is_first)} ? \"\" : \",\", \"${cov.file.path}\", ${nr_points} > 0 ? ((double)counter/${nr_points})*100 : 0, ${nr_points});")
+		g.cov_declarations.writeln("\t\t\tfprintf(fp, \"%s{\\\"file\\\":\\\"%s\\\",\\\"hits\\\":%d,\\\"points\\\":%d}\", ${int(is_first)} ? \"\" : \",\", \"${cov.file.path}\", counter, ${nr_points});")
 		if is_first {
 			is_first = !is_first
 		}

From a56142642363b1c66ec32946c79705f83bc58af9 Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Fri, 24 May 2024 15:38:13 -0300
Subject: [PATCH 13/38] wip

---
 vlib/v/gen/c/coverage.v | 11 ++++++-----
 vlib/v/pref/pref.v      |  6 +++---
 2 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 3610877394b337..47968dc647806d 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -4,6 +4,7 @@
 module c
 
 import v.token
+import os
 import rand { ulid }
 
 @[inline]
@@ -39,11 +40,11 @@ fn (mut g Gen) write_coverage_stats() {
 	build_hash := ulid()
 
 	g.cov_declarations.writeln('void vprint_coverage_stats() {')
-
-	g.cov_declarations.writeln('time_t rawtime;')
-	g.cov_declarations.writeln('char cov_filename[120];')
-	g.cov_declarations.writeln('time(&rawtime);')
-	g.cov_declarations.writeln('snprintf(cov_filename, 120, "vcover.%s.%s", "${build_hash}", vcoverage_fnv1a(asctime(localtime(&rawtime))));')
+	g.cov_declarations.writeln('\ttime_t rawtime;')
+	g.cov_declarations.writeln('\tchar cov_filename[120];')
+	g.cov_declarations.writeln('\ttime(&rawtime);')
+	g.cov_declarations.writeln('\tchar *cov_dir = getenv("VCOVDIR") != NULL ? getenv("VCOVDIR") : "${os.real_path(g.pref.coverage_dir)}";')
+	g.cov_declarations.writeln('\tsnprintf(cov_filename, 120, "%s/vcover.%s.%s", cov_dir, "${build_hash}", vcoverage_fnv1a(asctime(localtime(&rawtime))));')
 	g.cov_declarations.writeln('\tFILE *fp = fopen(cov_filename, "w+");')
 	g.cov_declarations.writeln('\tfprintf(fp, "[");')
 	g.cov_declarations.writeln('\tint t_counter = 0;')
diff --git a/vlib/v/pref/pref.v b/vlib/v/pref/pref.v
index c8603f3ca7f517..3d775efb739c54 100644
--- a/vlib/v/pref/pref.v
+++ b/vlib/v/pref/pref.v
@@ -120,7 +120,7 @@ pub mut:
 	eval_argument      string   // `println(2+2)` on `v -e "println(2+2)"`. Note that this source code, will be evaluated in vsh mode, so 'v -e 'println(ls(".")!)' is valid.
 	test_runner        string   // can be 'simple' (fastest, but much less detailed), 'tap', 'normal'
 	profile_file       string   // the profile results will be stored inside profile_file
-	coverage_file      string   // the coverage results will be stored inside coverage_file
+	coverage_dir       string   // the coverage files will be stored inside coverage_dir
 	profile_no_inline  bool     // when true, [inline] functions would not be profiled
 	profile_fns        []string // when set, profiling will be off by default, but inside these functions (and what they call) it will be on.
 	translated         bool     // `v translate doom.v` are we running V code translated from C? allow globals, ++ expressions, etc
@@ -604,9 +604,9 @@ pub fn parse_args_and_show_errors(known_external_commands []string, args []strin
 				i++
 			}
 			'-cov', '-coverage' {
-				res.coverage_file = cmdline.option(args[i..], arg, '-')
+				res.coverage_dir = cmdline.option(args[i..], arg, '-')
 				res.is_coverage = true
-				res.build_options << '${arg} ${res.coverage_file}'
+				res.build_options << '${arg} ${res.coverage_dir}'
 				i++
 			}
 			'-profile-fns' {

From 01ed4d75e0e50d6d2e96ad75964869bc11b55755 Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Sat, 25 May 2024 10:40:28 -0300
Subject: [PATCH 14/38] improve

---
 cmd/tools/vcover/vcover.v | 52 +++++++++++++++++++++++++++++++++------
 vlib/v/gen/c/cgen.v       |  2 +-
 vlib/v/gen/c/coverage.v   | 10 +++-----
 3 files changed, 49 insertions(+), 15 deletions(-)

diff --git a/cmd/tools/vcover/vcover.v b/cmd/tools/vcover/vcover.v
index a2ed4fcdaef2f0..bb795fe80c3a86 100644
--- a/cmd/tools/vcover/vcover.v
+++ b/cmd/tools/vcover/vcover.v
@@ -10,15 +10,24 @@ import arrays
 
 const tmp_dir = os.join_path(os.vtmp_dir(), 'cover')
 
+@[heap]
 struct VCoverData {
-	file   string // file name
-	hits   u64    // file coverage hits
-	points u64    // file counter
+	file string // file name
+mut:
+	hits   u64 // file coverage hits
+	points u64 // file counter
 }
 
-fn report_file(covfile string) ! {
-	json_content := os.read_file(covfile)!
-	data := json.decode([]VCoverData, json_content)!
+pub fn (covdata []&VCoverData) find(filename string) ?&VCoverData {
+	for data in covdata {
+		if data.file == filename {
+			return unsafe { data }
+		}
+	}
+	return none
+}
+
+fn display_result(data []VCoverData) ! {
 	hits := arrays.sum(data.map(it.hits))!
 	points := arrays.sum(data.map(it.points))!
 	for lineinfo in data {
@@ -27,13 +36,40 @@ fn report_file(covfile string) ! {
 	println('Total coverage: ${data.len} files, ${(f64(hits) / points) * 100:.2f}% coverage')
 }
 
+fn report_file(covfile string) ! {
+	json_content := os.read_file(covfile)!
+	data := json.decode([]VCoverData, json_content)!
+	display_result(data)!
+}
+
+fn summarize_coverage(covfile string, mut covdata []&VCoverData) ! {
+	json_content := os.read_file(covfile)!
+	data := json.decode([]VCoverData, json_content)!
+	for lineinfo in data {
+		if mut fileinfo := covdata.find(lineinfo.file) {
+			if fileinfo.hits < lineinfo.hits {
+				fileinfo.hits = lineinfo.hits
+			}
+		} else {
+			covdata << &VCoverData{
+				...lineinfo
+			}
+		}
+	}
+}
+
 fn main() {
 	args := cmdline.options_after(os.args, ['cover'])
 	covfile := os.real_path(cmdline.option(args, '-file', ''))
-	// covdir := os.real_path(cmdline.option(args, '-dir', ''))
-	// reportfile := os.real_path(cmdline.option(args, '-report', ''))
+	covdir := os.real_path(cmdline.option(args, '-dir', ''))
 
 	if covfile != '' {
 		report_file(covfile)!
+	} else if covdir != '' {
+		mut sum_data := []&VCoverData{}
+		for coverfile in os.glob(covdir + '/vcover.*')! {
+			summarize_coverage(coverfile, mut sum_data)!
+		}
+		display_result(sum_data.map(*it))!
 	}
 }
diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index d73dd295657934..f506a68889e419 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -2107,7 +2107,7 @@ fn (mut g Gen) write_v_source_line_info_stmt(stmt ast.Stmt) {
 		&& stmt !in [ast.FnDecl, ast.ForCStmt, ast.ForInStmt, ast.ForStmt] {
 		if stmt is ast.ExprStmt {
 			if !g.inside_assign
-				&& stmt.expr !in [ast.StringInterLiteral, ast.StringLiteral, ast.Ident, ast.UnsafeExpr] {
+				&& stmt.expr !in [ast.IndexExpr, ast.StringInterLiteral, ast.StringLiteral, ast.Ident, ast.UnsafeExpr] {
 				g.write_coverage_point(stmt.pos)
 			}
 		} else {
diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 47968dc647806d..35304fd7332e50 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -48,20 +48,18 @@ fn (mut g Gen) write_coverage_stats() {
 	g.cov_declarations.writeln('\tFILE *fp = fopen(cov_filename, "w+");')
 	g.cov_declarations.writeln('\tfprintf(fp, "[");')
 	g.cov_declarations.writeln('\tint t_counter = 0;')
+	g.cov_declarations.writeln('\tint is_first = 1;')
 	mut last_offset := 0
-	mut is_first := true
 	for k, cov in g.coverage_files {
 		nr_points := cov.points.len
 		g.cov_declarations.writeln('\t{')
 		g.cov_declarations.writeln('\t\tint counter = 0;')
-		g.cov_declarations.writeln('\t\tfor (int i = 0, offset = ${last_offset}; i < ${nr_points}; ++i)')
+		g.cov_declarations.writeln('\t\tfor (int i = 0, is_first = 1, offset = ${last_offset}; i < ${nr_points}; ++i)')
 		g.cov_declarations.writeln('\t\t\tif (_v_cov[_v_cov_file_offset_${k}+i]) counter++;')
 		g.cov_declarations.writeln('\t\tt_counter += counter;')
 		g.cov_declarations.writeln('\t\tif (counter) {')
-		g.cov_declarations.writeln("\t\t\tfprintf(fp, \"%s{\\\"file\\\":\\\"%s\\\",\\\"hits\\\":%d,\\\"points\\\":%d}\", ${int(is_first)} ? \"\" : \",\", \"${cov.file.path}\", counter, ${nr_points});")
-		if is_first {
-			is_first = !is_first
-		}
+		g.cov_declarations.writeln("\t\t\tfprintf(fp, \"%s{\\\"file\\\":\\\"%s\\\",\\\"hits\\\":%d,\\\"points\\\":%d}\", is_first ? \"\" : \",\", \"${cov.file.path}\", counter, ${nr_points});")
+		g.cov_declarations.writeln('\t\t\tis_first = 0;')
 		g.cov_declarations.writeln('\t\t}')
 		g.cov_declarations.writeln('\t}')
 		last_offset += nr_points

From 1096fb5438b79c1e2ce7b395d88b269259846c0f Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Sat, 25 May 2024 11:01:21 -0300
Subject: [PATCH 15/38] fix

---
 vlib/v/gen/c/cgen.v | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index f506a68889e419..c3f83383942ccf 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -2107,7 +2107,7 @@ fn (mut g Gen) write_v_source_line_info_stmt(stmt ast.Stmt) {
 		&& stmt !in [ast.FnDecl, ast.ForCStmt, ast.ForInStmt, ast.ForStmt] {
 		if stmt is ast.ExprStmt {
 			if !g.inside_assign
-				&& stmt.expr !in [ast.IndexExpr, ast.StringInterLiteral, ast.StringLiteral, ast.Ident, ast.UnsafeExpr] {
+				&& stmt.expr !in [ast.CastExpr, ast.IndexExpr, ast.StringInterLiteral, ast.StringLiteral, ast.Ident, ast.UnsafeExpr] {
 				g.write_coverage_point(stmt.pos)
 			}
 		} else {

From c80b978519e4034d30e8c64465078777334602fe Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Sat, 25 May 2024 11:32:17 -0300
Subject: [PATCH 16/38] added -filter

---
 cmd/tools/vcover/vcover.v | 34 +++++++++++++++++++++++++---------
 1 file changed, 25 insertions(+), 9 deletions(-)

diff --git a/cmd/tools/vcover/vcover.v b/cmd/tools/vcover/vcover.v
index bb795fe80c3a86..7107ebbbc79715 100644
--- a/cmd/tools/vcover/vcover.v
+++ b/cmd/tools/vcover/vcover.v
@@ -27,19 +27,34 @@ pub fn (covdata []&VCoverData) find(filename string) ?&VCoverData {
 	return none
 }
 
-fn display_result(data []VCoverData) ! {
-	hits := arrays.sum(data.map(it.hits))!
-	points := arrays.sum(data.map(it.points))!
-	for lineinfo in data {
+pub fn (covdata []VCoverData) filter_data(filters []string) []VCoverData {
+	mut arr := []VCoverData{}
+	for data in covdata {
+		if filters.any(data.file.contains(it)) {
+			arr << data
+		}
+	}
+	return arr
+}
+
+fn display_result(filter string, data []VCoverData) ! {
+	mut covdata := data.clone()
+	if filter != '' {
+		filters := filter.split(',')
+		covdata = covdata.filter_data(filters)
+	}
+	hits := arrays.sum(covdata.map(it.hits))!
+	points := arrays.sum(covdata.map(it.points))!
+	for lineinfo in covdata {
 		println('${(f64(lineinfo.hits) / lineinfo.points) * 100:7.2f} | ${lineinfo.hits:4u} | ${lineinfo.points:4u} | ${lineinfo.file}')
 	}
-	println('Total coverage: ${data.len} files, ${(f64(hits) / points) * 100:.2f}% coverage')
+	println('Total coverage: ${covdata.len} files, ${(f64(hits) / points) * 100:.2f}% coverage')
 }
 
-fn report_file(covfile string) ! {
+fn report_file(filter string, covfile string) ! {
 	json_content := os.read_file(covfile)!
 	data := json.decode([]VCoverData, json_content)!
-	display_result(data)!
+	display_result(filter, data)!
 }
 
 fn summarize_coverage(covfile string, mut covdata []&VCoverData) ! {
@@ -62,14 +77,15 @@ fn main() {
 	args := cmdline.options_after(os.args, ['cover'])
 	covfile := os.real_path(cmdline.option(args, '-file', ''))
 	covdir := os.real_path(cmdline.option(args, '-dir', ''))
+	filter := cmdline.option(args, '-filter', '')
 
 	if covfile != '' {
-		report_file(covfile)!
+		report_file(filter, covfile)!
 	} else if covdir != '' {
 		mut sum_data := []&VCoverData{}
 		for coverfile in os.glob(covdir + '/vcover.*')! {
 			summarize_coverage(coverfile, mut sum_data)!
 		}
-		display_result(sum_data.map(*it))!
+		display_result(filter, sum_data.map(*it))!
 	}
 }

From 73c387835b367b88d6b037160f8488cae4e3ae59 Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Sat, 25 May 2024 11:52:58 -0300
Subject: [PATCH 17/38] ignore test funcs

---
 cmd/tools/vcover/vcover.v | 7 +++++--
 vlib/v/gen/c/coverage.v   | 2 +-
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/cmd/tools/vcover/vcover.v b/cmd/tools/vcover/vcover.v
index 7107ebbbc79715..06761a32c2523a 100644
--- a/cmd/tools/vcover/vcover.v
+++ b/cmd/tools/vcover/vcover.v
@@ -42,6 +42,9 @@ fn display_result(filter string, data []VCoverData) ! {
 	if filter != '' {
 		filters := filter.split(',')
 		covdata = covdata.filter_data(filters)
+		if covdata.len == 0 {
+			return error('No result found with such filter')
+		}
 	}
 	hits := arrays.sum(covdata.map(it.hits))!
 	points := arrays.sum(covdata.map(it.points))!
@@ -80,12 +83,12 @@ fn main() {
 	filter := cmdline.option(args, '-filter', '')
 
 	if covfile != '' {
-		report_file(filter, covfile)!
+		report_file(filter, covfile) or { println('Error: ${err}') }
 	} else if covdir != '' {
 		mut sum_data := []&VCoverData{}
 		for coverfile in os.glob(covdir + '/vcover.*')! {
 			summarize_coverage(coverfile, mut sum_data)!
 		}
-		display_result(filter, sum_data.map(*it))!
+		display_result(filter, sum_data.map(*it)) or { println('Error: ${err}') }
 	}
 }
diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 35304fd7332e50..655490c32b49ba 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -15,7 +15,7 @@ fn (mut g Gen) write_coverage_point(pos token.Pos) {
 			file: g.file
 		}
 	}
-	if g.fn_decl != unsafe { nil } {
+	if g.fn_decl != unsafe { nil } && !g.fn_decl.is_test {
 		curr_line := u64(pos.line_nr)
 		mut curr_cov := unsafe { g.coverage_files[g.unique_file_path_hash] }
 		if curr_line !in curr_cov.points {

From 0d6665fbcb41327899eb6319e6f647db91f3d27a Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Sat, 25 May 2024 12:06:35 -0300
Subject: [PATCH 18/38] improve filtering

---
 cmd/tools/vcover/vcover.v | 11 ++++++++---
 vlib/v/gen/c/coverage.v   |  2 +-
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/cmd/tools/vcover/vcover.v b/cmd/tools/vcover/vcover.v
index 06761a32c2523a..de4e5086dc1ada 100644
--- a/cmd/tools/vcover/vcover.v
+++ b/cmd/tools/vcover/vcover.v
@@ -27,10 +27,13 @@ pub fn (covdata []&VCoverData) find(filename string) ?&VCoverData {
 	return none
 }
 
-pub fn (covdata []VCoverData) filter_data(filters []string) []VCoverData {
+pub fn (covdata []VCoverData) filter_files(filters []string, remove_test bool) []VCoverData {
 	mut arr := []VCoverData{}
 	for data in covdata {
-		if filters.any(data.file.contains(it)) {
+		if remove_test && data.file.ends_with('_test.v') {
+			continue
+		}
+		if filters.len == 0 || filters.any(data.file.contains(it)) {
 			arr << data
 		}
 	}
@@ -41,10 +44,12 @@ fn display_result(filter string, data []VCoverData) ! {
 	mut covdata := data.clone()
 	if filter != '' {
 		filters := filter.split(',')
-		covdata = covdata.filter_data(filters)
+		covdata = covdata.filter_files(filters, true)
 		if covdata.len == 0 {
 			return error('No result found with such filter')
 		}
+	} else {
+		covdata = covdata.filter_files([], true)
 	}
 	hits := arrays.sum(covdata.map(it.hits))!
 	points := arrays.sum(covdata.map(it.points))!
diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 655490c32b49ba..35304fd7332e50 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -15,7 +15,7 @@ fn (mut g Gen) write_coverage_point(pos token.Pos) {
 			file: g.file
 		}
 	}
-	if g.fn_decl != unsafe { nil } && !g.fn_decl.is_test {
+	if g.fn_decl != unsafe { nil } {
 		curr_line := u64(pos.line_nr)
 		mut curr_cov := unsafe { g.coverage_files[g.unique_file_path_hash] }
 		if curr_line !in curr_cov.points {

From d16866fcf7d8fb2c0be42acb007c3fc52657c7a4 Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sat, 25 May 2024 19:53:52 +0300
Subject: [PATCH 19/38] change format to csv, add more details, add
 cmd/tools/vcover/testdata/example1 for more isolated testing, independent of
 the contents of any vlib module in particular

---
 cmd/tools/vcover/testdata/example1/abc.v      | 313 ++++++++++++++++++
 .../testdata/example1/internal_abc01_test.v   |   5 +
 .../example1/internal_abc10_abc30_test.v      |  25 ++
 .../example1/internal_abc20_abc25_test.v      |  10 +
 cmd/tools/vcover/testdata/example1/v.mod      |   0
 vlib/v/gen/c/cgen.v                           |   2 +-
 vlib/v/gen/c/coverage.v                       |  44 +--
 7 files changed, 368 insertions(+), 31 deletions(-)
 create mode 100644 cmd/tools/vcover/testdata/example1/abc.v
 create mode 100644 cmd/tools/vcover/testdata/example1/internal_abc01_test.v
 create mode 100644 cmd/tools/vcover/testdata/example1/internal_abc10_abc30_test.v
 create mode 100644 cmd/tools/vcover/testdata/example1/internal_abc20_abc25_test.v
 create mode 100644 cmd/tools/vcover/testdata/example1/v.mod

diff --git a/cmd/tools/vcover/testdata/example1/abc.v b/cmd/tools/vcover/testdata/example1/abc.v
new file mode 100644
index 00000000000000..c062e09e7c2e80
--- /dev/null
+++ b/cmd/tools/vcover/testdata/example1/abc.v
@@ -0,0 +1,313 @@
+module example1
+
+fn abc01() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc02() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc03() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc04() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc05() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc06() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc07() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc08() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc09() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc10() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc11() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc12() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc13() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc14() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc15() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc16() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc17() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc18() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc19() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc20() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc21() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc22() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc23() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc24() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc25() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc26() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc27() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc28() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc29() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc30() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc31() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc32() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc33() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc34() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc35() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc36() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc37() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc38() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
+
+fn abc39() {
+	if true {
+		println('true')
+	} else {
+		println(false)
+	}
+}
diff --git a/cmd/tools/vcover/testdata/example1/internal_abc01_test.v b/cmd/tools/vcover/testdata/example1/internal_abc01_test.v
new file mode 100644
index 00000000000000..3d4f09c4d729e5
--- /dev/null
+++ b/cmd/tools/vcover/testdata/example1/internal_abc01_test.v
@@ -0,0 +1,5 @@
+module example1
+
+fn test_abc() {
+	abc01()
+}
diff --git a/cmd/tools/vcover/testdata/example1/internal_abc10_abc30_test.v b/cmd/tools/vcover/testdata/example1/internal_abc10_abc30_test.v
new file mode 100644
index 00000000000000..b0252f8daa9ab5
--- /dev/null
+++ b/cmd/tools/vcover/testdata/example1/internal_abc10_abc30_test.v
@@ -0,0 +1,25 @@
+module example1
+
+fn test_abc() {
+	abc10()
+	abc11()
+	abc12()
+	abc13()
+	abc14()
+	abc15()
+	abc16()
+	abc17()
+	abc18()
+	abc19()
+	abc20()
+	abc21()
+	abc22()
+	abc23()
+	abc24()
+	abc25()
+	abc26()
+	abc27()
+	abc28()
+	abc29()
+	abc30()
+}
diff --git a/cmd/tools/vcover/testdata/example1/internal_abc20_abc25_test.v b/cmd/tools/vcover/testdata/example1/internal_abc20_abc25_test.v
new file mode 100644
index 00000000000000..c3ca1c646f5e0a
--- /dev/null
+++ b/cmd/tools/vcover/testdata/example1/internal_abc20_abc25_test.v
@@ -0,0 +1,10 @@
+module example1
+
+fn test_abc() {
+	abc20()
+	abc21()
+	abc22()
+	abc23()
+	abc24()
+	abc25()
+}
diff --git a/cmd/tools/vcover/testdata/example1/v.mod b/cmd/tools/vcover/testdata/example1/v.mod
new file mode 100644
index 00000000000000..e69de29bb2d1d6
diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index c3f83383942ccf..bff270b997e964 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -527,7 +527,7 @@ pub fn gen(files []&ast.File, mut table ast.Table, pref_ &pref.Preferences) (str
 			g.cheaders.writeln('#define _v_cov_file_offset_${k} ${total_code_points}')
 			total_code_points += cov.points.len
 		}
-		g.cheaders.writeln('char _v_cov[${total_code_points}] = {0};')
+		g.cheaders.writeln('long int _v_cov[${total_code_points}] = {0};')
 	}
 
 	// insert for options forward
diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 35304fd7332e50..878211b9a10896 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -5,7 +5,7 @@ module c
 
 import v.token
 import os
-import rand { ulid }
+import rand
 
 @[inline]
 fn (mut g Gen) write_coverage_point(pos token.Pos) {
@@ -21,49 +21,33 @@ fn (mut g Gen) write_coverage_point(pos token.Pos) {
 		if curr_line !in curr_cov.points {
 			curr_cov.points << curr_line
 		}
-		g.writeln('_v_cov[_v_cov_file_offset_${g.unique_file_path_hash}+${curr_cov.points.len - 1}] = 1;')
+		g.writeln('_v_cov[_v_cov_file_offset_${g.unique_file_path_hash}+${curr_cov.points.len - 1}]++;')
 	}
 }
 
 fn (mut g Gen) write_coverage_stats() {
-	g.cov_declarations.writeln('char* vcoverage_fnv1a(const u8* data) {')
-	g.cov_declarations.writeln('\tu32 h = 2166136261UL;')
-	g.cov_declarations.writeln('\tsize_t size = strlen(data);')
-	g.cov_declarations.writeln('\tfor (size_t i = 0; i < size; i++) {')
-	g.cov_declarations.writeln('\th ^= data[i];')
-	g.cov_declarations.writeln('\th *= 16777619;')
-	g.cov_declarations.writeln('\t}')
-	g.cov_declarations.writeln('\treturn u32_str(h).str;')
-	g.cov_declarations.writeln('}')
+	ulid_hash := rand.ulid() // rand.ulid provides a hash+timestamp, so that a collision is extremely unlikely
 	g.cov_declarations.writeln('')
-
-	build_hash := ulid()
-
 	g.cov_declarations.writeln('void vprint_coverage_stats() {')
-	g.cov_declarations.writeln('\ttime_t rawtime;')
-	g.cov_declarations.writeln('\tchar cov_filename[120];')
-	g.cov_declarations.writeln('\ttime(&rawtime);')
+	// g.cov_declarations.writeln('\tstruct timespec ts;')
+	// g.cov_declarations.writeln('\tclock_gettime(CLOCK_MONOTONIC, &ts);')
+	g.cov_declarations.writeln('\tchar cov_filename[512];')
 	g.cov_declarations.writeln('\tchar *cov_dir = getenv("VCOVDIR") != NULL ? getenv("VCOVDIR") : "${os.real_path(g.pref.coverage_dir)}";')
-	g.cov_declarations.writeln('\tsnprintf(cov_filename, 120, "%s/vcover.%s.%s", cov_dir, "${build_hash}", vcoverage_fnv1a(asctime(localtime(&rawtime))));')
-	g.cov_declarations.writeln('\tFILE *fp = fopen(cov_filename, "w+");')
-	g.cov_declarations.writeln('\tfprintf(fp, "[");')
-	g.cov_declarations.writeln('\tint t_counter = 0;')
-	g.cov_declarations.writeln('\tint is_first = 1;')
+	g.cov_declarations.writeln('\tsnprintf(cov_filename, sizeof(cov_filename), "%s/vcover_${ulid_hash}.csv", cov_dir);')
+	g.cov_declarations.writeln('\tFILE *fp = fopen(cov_filename, "wb+");')
+	g.cov_declarations.writeln('\tfprintf(fp, "file,points,counter,hits\\n");')
 	mut last_offset := 0
 	for k, cov in g.coverage_files {
 		nr_points := cov.points.len
 		g.cov_declarations.writeln('\t{')
-		g.cov_declarations.writeln('\t\tint counter = 0;')
-		g.cov_declarations.writeln('\t\tfor (int i = 0, is_first = 1, offset = ${last_offset}; i < ${nr_points}; ++i)')
-		g.cov_declarations.writeln('\t\t\tif (_v_cov[_v_cov_file_offset_${k}+i]) counter++;')
-		g.cov_declarations.writeln('\t\tt_counter += counter;')
-		g.cov_declarations.writeln('\t\tif (counter) {')
-		g.cov_declarations.writeln("\t\t\tfprintf(fp, \"%s{\\\"file\\\":\\\"%s\\\",\\\"hits\\\":%d,\\\"points\\\":%d}\", is_first ? \"\" : \",\", \"${cov.file.path}\", counter, ${nr_points});")
-		g.cov_declarations.writeln('\t\t\tis_first = 0;')
+		g.cov_declarations.writeln('\t\tfor (int i = 0, offset = ${last_offset}; i < ${nr_points}; ++i) {')
+		g.cov_declarations.writeln('\t\t\tif (_v_cov[_v_cov_file_offset_${k}+i]) {')
+		g.cov_declarations.writeln("\t\t\t\tfprintf(fp, \"\\\"%s\\\",%d,%d,%ld\\n\", \"${cov.file.path}\", ${nr_points}, i, _v_cov[_v_cov_file_offset_${k}+i]);")
+		g.cov_declarations.writeln('\t\t\t}')
 		g.cov_declarations.writeln('\t\t}')
 		g.cov_declarations.writeln('\t}')
 		last_offset += nr_points
 	}
-	g.cov_declarations.writeln('\tfprintf(fp, "]");')
+	g.cov_declarations.writeln('\tfclose(fp);')
 	g.cov_declarations.writeln('}')
 }

From 2f4dbb1103d9c0e6e3aa8606b66829228d81dbed Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sat, 25 May 2024 22:01:58 +0300
Subject: [PATCH 20/38] make test runs of cmd/tools/vcover/testdata/example1/
 silent for now

---
 cmd/tools/vcover/testdata/example1/abc.v | 234 +++++++++++------------
 1 file changed, 117 insertions(+), 117 deletions(-)

diff --git a/cmd/tools/vcover/testdata/example1/abc.v b/cmd/tools/vcover/testdata/example1/abc.v
index c062e09e7c2e80..cd2e92f3a36824 100644
--- a/cmd/tools/vcover/testdata/example1/abc.v
+++ b/cmd/tools/vcover/testdata/example1/abc.v
@@ -1,313 +1,313 @@
 module example1
 
-fn abc01() {
+fn abc01() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 2
 	}
 }
 
-fn abc02() {
+fn abc02() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc03() {
+fn abc03() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc04() {
+fn abc04() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc05() {
+fn abc05() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc06() {
+fn abc06() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc07() {
+fn abc07() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc08() {
+fn abc08() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc09() {
+fn abc09() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc10() {
+fn abc10() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc11() {
+fn abc11() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc12() {
+fn abc12() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc13() {
+fn abc13() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc14() {
+fn abc14() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc15() {
+fn abc15() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc16() {
+fn abc16() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc17() {
+fn abc17() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc18() {
+fn abc18() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc19() {
+fn abc19() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc20() {
+fn abc20() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc21() {
+fn abc21() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc22() {
+fn abc22() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc23() {
+fn abc23() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc24() {
+fn abc24() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc25() {
+fn abc25() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc26() {
+fn abc26() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc27() {
+fn abc27() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc28() {
+fn abc28() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc29() {
+fn abc29() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc30() {
+fn abc30() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc31() {
+fn abc31() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc32() {
+fn abc32() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc33() {
+fn abc33() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc34() {
+fn abc34() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc35() {
+fn abc35() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc36() {
+fn abc36() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc37() {
+fn abc37() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc38() {
+fn abc38() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }
 
-fn abc39() {
+fn abc39() int {
 	if true {
-		println('true')
+		return 1
 	} else {
-		println(false)
+		return 0
 	}
 }

From 622ed4a9de0640a403b0cc0a953175943f6afc30 Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sat, 25 May 2024 22:46:48 +0300
Subject: [PATCH 21/38] cleanup output format for both the csv counters, and
 the json meta data for the source files, containing the points, etc

---
 vlib/v/gen/c/cgen.v     |  9 ------
 vlib/v/gen/c/coverage.v | 66 +++++++++++++++++++++++++++++++++--------
 vlib/v/pref/pref.v      | 10 +++++--
 3 files changed, 61 insertions(+), 24 deletions(-)

diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index bff270b997e964..a1ae5829f528f4 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -42,15 +42,6 @@ fn string_array_to_map(a []string) map[string]bool {
 	return res
 }
 
-// V coverage info
-@[heap]
-struct CoverageInfo {
-pub mut:
-	idx    int   // index
-	points []u64 // code point line nr
-	file   &ast.File = unsafe { nil }
-}
-
 pub struct Gen {
 	pref                &pref.Preferences = unsafe { nil }
 	field_data_type     ast.Type // cache her to avoid map lookups
diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 878211b9a10896..708c6dc677fdf3 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -3,16 +3,33 @@
 // that can be found in the LICENSE file.
 module c
 
-import v.token
 import os
 import rand
+import v.ast
+import v.token
+import v.util.version
+import hash
+
+// V coverage info
+@[heap]
+struct CoverageInfo {
+mut:
+	idx           int   // index
+	points        []u64 // code point line nr
+	file          &ast.File = unsafe { nil }
+	fhash         string // hash(fpath, build_options), prevents collisions for runs with different options, like `-os windows` or `-gc none`, which may affect the points, due to `$if ... {` etc
+	build_options string
+}
 
-@[inline]
 fn (mut g Gen) write_coverage_point(pos token.Pos) {
 	if g.unique_file_path_hash !in g.coverage_files {
+		build_options := g.pref.build_options.join(' ')
+		fhash := hash.sum64_string('${build_options}:${g.unique_file_path_hash}', 32).hex_full()
 		g.coverage_files[g.unique_file_path_hash] = &CoverageInfo{
 			points: []
 			file: g.file
+			fhash: fhash
+			build_options: build_options
 		}
 	}
 	if g.fn_decl != unsafe { nil } {
@@ -26,27 +43,50 @@ fn (mut g Gen) write_coverage_point(pos token.Pos) {
 }
 
 fn (mut g Gen) write_coverage_stats() {
-	ulid_hash := rand.ulid() // rand.ulid provides a hash+timestamp, so that a collision is extremely unlikely
+	coverage_meta_folder := os.join_path(g.pref.coverage_dir, 'meta')
+	if !os.exists(coverage_meta_folder) {
+		os.mkdir_all(coverage_meta_folder) or {}
+	}
+	counter_ulid := rand.ulid() // rand.ulid provides a hash+timestamp, so that a collision is extremely unlikely
 	g.cov_declarations.writeln('')
 	g.cov_declarations.writeln('void vprint_coverage_stats() {')
-	// g.cov_declarations.writeln('\tstruct timespec ts;')
-	// g.cov_declarations.writeln('\tclock_gettime(CLOCK_MONOTONIC, &ts);')
-	g.cov_declarations.writeln('\tchar cov_filename[512];')
-	g.cov_declarations.writeln('\tchar *cov_dir = getenv("VCOVDIR") != NULL ? getenv("VCOVDIR") : "${os.real_path(g.pref.coverage_dir)}";')
-	g.cov_declarations.writeln('\tsnprintf(cov_filename, sizeof(cov_filename), "%s/vcover_${ulid_hash}.csv", cov_dir);')
+	g.cov_declarations.writeln('\tchar cov_filename[2048];')
+	g.cov_declarations.writeln('\tchar *cov_dir = "${os.real_path(g.pref.coverage_dir)}";')
+	for _, mut cov in g.coverage_files {
+		metadata_coverage_fpath := os.join_path(coverage_meta_folder, '${cov.fhash}.txt')
+		if os.exists(metadata_coverage_fpath) {
+			continue
+		}
+		mut fmeta := os.create(metadata_coverage_fpath) or { continue }
+		fmeta.writeln('{') or { continue }
+		fmeta.writeln('  "file": "${cov.file.path}",') or { continue }
+		fmeta.writeln('  "v_version": "${version.full_v_version(true)}",') or { continue }
+		fmeta.writeln('  "build_options": "${cov.build_options}",') or { continue }
+		fmeta.writeln('  "npoints": ${cov.points.len},') or { continue }
+		fmeta.write_string('  "points": [  ') or { continue }
+		for idx, p in cov.points {
+			fmeta.write_string('${p + 1}') or { continue }
+			if idx < cov.points.len - 1 {
+				fmeta.write_string(',') or { continue }
+			}
+		}
+		fmeta.writeln('  ]') or { continue }
+		fmeta.writeln('}') or { continue }
+		fmeta.close()
+	}
+	g.cov_declarations.writeln('\tsnprintf(cov_filename, sizeof(cov_filename), "%s/vcounters_${counter_ulid}.csv", cov_dir);')
 	g.cov_declarations.writeln('\tFILE *fp = fopen(cov_filename, "wb+");')
-	g.cov_declarations.writeln('\tfprintf(fp, "file,points,counter,hits\\n");')
-	mut last_offset := 0
+	g.cov_declarations.writeln('\tfprintf(fp, "# path: ${g.pref.path}\\n");')
+	g.cov_declarations.writeln('\tfprintf(fp, "meta,point,hits\\n");')
 	for k, cov in g.coverage_files {
 		nr_points := cov.points.len
 		g.cov_declarations.writeln('\t{')
-		g.cov_declarations.writeln('\t\tfor (int i = 0, offset = ${last_offset}; i < ${nr_points}; ++i) {')
+		g.cov_declarations.writeln('\t\tfor (int i = 0; i < ${nr_points}; ++i) {')
 		g.cov_declarations.writeln('\t\t\tif (_v_cov[_v_cov_file_offset_${k}+i]) {')
-		g.cov_declarations.writeln("\t\t\t\tfprintf(fp, \"\\\"%s\\\",%d,%d,%ld\\n\", \"${cov.file.path}\", ${nr_points}, i, _v_cov[_v_cov_file_offset_${k}+i]);")
+		g.cov_declarations.writeln("\t\t\t\tfprintf(fp, \"%s,%d,%ld\\n\", \"${cov.fhash}\", i, _v_cov[_v_cov_file_offset_${k}+i]);")
 		g.cov_declarations.writeln('\t\t\t}')
 		g.cov_declarations.writeln('\t\t}')
 		g.cov_declarations.writeln('\t}')
-		last_offset += nr_points
 	}
 	g.cov_declarations.writeln('\tfclose(fp);')
 	g.cov_declarations.writeln('}')
diff --git a/vlib/v/pref/pref.v b/vlib/v/pref/pref.v
index 3d775efb739c54..8e70d93e8eefe6 100644
--- a/vlib/v/pref/pref.v
+++ b/vlib/v/pref/pref.v
@@ -310,6 +310,10 @@ pub fn parse_args_and_show_errors(known_external_commands []string, args []strin
 	if os.getenv('VNORUN') != '' {
 		res.skip_running = true
 	}
+	coverage_dir_from_env := os.getenv('VCOVDIR')
+	if coverage_dir_from_env != '' {
+		res.coverage_dir = coverage_dir_from_env
+	}
 	/* $if macos || linux {
 		res.use_cache = true
 		res.skip_unused = true
@@ -605,8 +609,6 @@ pub fn parse_args_and_show_errors(known_external_commands []string, args []strin
 			}
 			'-cov', '-coverage' {
 				res.coverage_dir = cmdline.option(args[i..], arg, '-')
-				res.is_coverage = true
-				res.build_options << '${arg} ${res.coverage_dir}'
 				i++
 			}
 			'-profile-fns' {
@@ -1073,6 +1075,10 @@ pub fn parse_args_and_show_errors(known_external_commands []string, args []strin
 	if 'trace' in res.compile_defines_all {
 		res.is_trace = true
 	}
+	if res.coverage_dir != '' {
+		res.is_coverage = true
+		res.build_options << '-coverage ${res.coverage_dir}'
+	}
 	// keep only the unique res.build_options:
 	mut m := map[string]string{}
 	for x in res.build_options {

From def6f9b6e4290a3786e56075face32c91d79f32d Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sat, 25 May 2024 22:59:36 +0300
Subject: [PATCH 22/38] add the build options to the .csv file too, as a
 comment (for easier diagnostic); add condition_test.v, to test coverage by
 passing `-d condition1` to `-d condition7`

---
 .../vcover/testdata/example1/condition.v      | 30 +++++++++++++++++++
 .../vcover/testdata/example1/condition_test.v |  5 ++++
 vlib/v/gen/c/coverage.v                       |  2 ++
 3 files changed, 37 insertions(+)
 create mode 100644 cmd/tools/vcover/testdata/example1/condition.v
 create mode 100644 cmd/tools/vcover/testdata/example1/condition_test.v

diff --git a/cmd/tools/vcover/testdata/example1/condition.v b/cmd/tools/vcover/testdata/example1/condition.v
new file mode 100644
index 00000000000000..86ff777086e177
--- /dev/null
+++ b/cmd/tools/vcover/testdata/example1/condition.v
@@ -0,0 +1,30 @@
+module example1
+
+fn condition() int {
+	mut res := 0
+	$if condition1 ? {
+		res += 1
+	}
+	$if condition2 ? {
+		res += 2
+	}
+	$if condition3 ? {
+		res += 4
+	}
+	$if condition4 ? {
+		res += 8
+	}
+	$if condition5 ? {
+		res += 16
+	}
+	$if condition6 ? {
+		res += 32
+	}
+	$if condition7 ? {
+		res += 64
+	}
+	$if condition8 ? {
+		return 128
+	}
+	return res
+}
diff --git a/cmd/tools/vcover/testdata/example1/condition_test.v b/cmd/tools/vcover/testdata/example1/condition_test.v
new file mode 100644
index 00000000000000..a929b0fc390071
--- /dev/null
+++ b/cmd/tools/vcover/testdata/example1/condition_test.v
@@ -0,0 +1,5 @@
+module example1
+
+fn test_condition() {
+	println(condition())
+}
diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 708c6dc677fdf3..203d3bd129d97b 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -43,6 +43,7 @@ fn (mut g Gen) write_coverage_point(pos token.Pos) {
 }
 
 fn (mut g Gen) write_coverage_stats() {
+	build_options := g.pref.build_options.join(' ')
 	coverage_meta_folder := os.join_path(g.pref.coverage_dir, 'meta')
 	if !os.exists(coverage_meta_folder) {
 		os.mkdir_all(coverage_meta_folder) or {}
@@ -77,6 +78,7 @@ fn (mut g Gen) write_coverage_stats() {
 	g.cov_declarations.writeln('\tsnprintf(cov_filename, sizeof(cov_filename), "%s/vcounters_${counter_ulid}.csv", cov_dir);')
 	g.cov_declarations.writeln('\tFILE *fp = fopen(cov_filename, "wb+");')
 	g.cov_declarations.writeln('\tfprintf(fp, "# path: ${g.pref.path}\\n");')
+	g.cov_declarations.writeln('\tfprintf(fp, "# build_options: ${build_options}\\n");')
 	g.cov_declarations.writeln('\tfprintf(fp, "meta,point,hits\\n");')
 	for k, cov in g.coverage_files {
 		nr_points := cov.points.len

From 44b0c08c9bd7c328e0897800974b8918322b9995 Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sat, 25 May 2024 23:26:52 +0300
Subject: [PATCH 23/38] move condition_test.v to a separate folder example2/

---
 cmd/tools/vcover/testdata/example1/condition_test.v          | 5 -----
 cmd/tools/vcover/testdata/{example1 => example2}/condition.v | 4 ++--
 cmd/tools/vcover/testdata/example2/condition_test.v          | 5 +++++
 cmd/tools/vcover/testdata/example2/v.mod                     | 0
 4 files changed, 7 insertions(+), 7 deletions(-)
 delete mode 100644 cmd/tools/vcover/testdata/example1/condition_test.v
 rename cmd/tools/vcover/testdata/{example1 => example2}/condition.v (88%)
 create mode 100644 cmd/tools/vcover/testdata/example2/condition_test.v
 create mode 100644 cmd/tools/vcover/testdata/example2/v.mod

diff --git a/cmd/tools/vcover/testdata/example1/condition_test.v b/cmd/tools/vcover/testdata/example1/condition_test.v
deleted file mode 100644
index a929b0fc390071..00000000000000
--- a/cmd/tools/vcover/testdata/example1/condition_test.v
+++ /dev/null
@@ -1,5 +0,0 @@
-module example1
-
-fn test_condition() {
-	println(condition())
-}
diff --git a/cmd/tools/vcover/testdata/example1/condition.v b/cmd/tools/vcover/testdata/example2/condition.v
similarity index 88%
rename from cmd/tools/vcover/testdata/example1/condition.v
rename to cmd/tools/vcover/testdata/example2/condition.v
index 86ff777086e177..900fd3ec932f5d 100644
--- a/cmd/tools/vcover/testdata/example1/condition.v
+++ b/cmd/tools/vcover/testdata/example2/condition.v
@@ -1,6 +1,6 @@
-module example1
+module example2
 
-fn condition() int {
+pub fn condition() int {
 	mut res := 0
 	$if condition1 ? {
 		res += 1
diff --git a/cmd/tools/vcover/testdata/example2/condition_test.v b/cmd/tools/vcover/testdata/example2/condition_test.v
new file mode 100644
index 00000000000000..07f20ac13464d1
--- /dev/null
+++ b/cmd/tools/vcover/testdata/example2/condition_test.v
@@ -0,0 +1,5 @@
+import example2
+
+fn test_condition() {
+	println(example2.condition())
+}
diff --git a/cmd/tools/vcover/testdata/example2/v.mod b/cmd/tools/vcover/testdata/example2/v.mod
new file mode 100644
index 00000000000000..e69de29bb2d1d6

From 0b03e8719fef4db340172334aaf8838e728de387 Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sun, 26 May 2024 01:16:52 +0300
Subject: [PATCH 24/38] fix `# build_options` in cgen for `v -cc clang -cstrict
 -gc none -cov /tmp/cover/ a.v`, restore runtime timestamp for the counter
 files

---
 vlib/v/gen/c/coverage.v | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 203d3bd129d97b..530830ea3f87cf 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -60,7 +60,7 @@ fn (mut g Gen) write_coverage_stats() {
 		}
 		mut fmeta := os.create(metadata_coverage_fpath) or { continue }
 		fmeta.writeln('{') or { continue }
-		fmeta.writeln('  "file": "${cov.file.path}",') or { continue }
+		fmeta.writeln('  "file": "${cov.file.path}", "fhash": "${cov.fhash}",') or { continue }
 		fmeta.writeln('  "v_version": "${version.full_v_version(true)}",') or { continue }
 		fmeta.writeln('  "build_options": "${cov.build_options}",') or { continue }
 		fmeta.writeln('  "npoints": ${cov.points.len},') or { continue }
@@ -75,10 +75,12 @@ fn (mut g Gen) write_coverage_stats() {
 		fmeta.writeln('}') or { continue }
 		fmeta.close()
 	}
-	g.cov_declarations.writeln('\tsnprintf(cov_filename, sizeof(cov_filename), "%s/vcounters_${counter_ulid}.csv", cov_dir);')
+	g.cov_declarations.writeln('\tstruct timespec ts;')
+	g.cov_declarations.writeln('\tclock_gettime(CLOCK_MONOTONIC, &ts);')
+	g.cov_declarations.writeln('\tsnprintf(cov_filename, sizeof(cov_filename), "%s/vcounters_${counter_ulid}.%ld.%ld.csv", cov_dir, ts.tv_sec, ts.tv_nsec);')
 	g.cov_declarations.writeln('\tFILE *fp = fopen(cov_filename, "wb+");')
 	g.cov_declarations.writeln('\tfprintf(fp, "# path: ${g.pref.path}\\n");')
-	g.cov_declarations.writeln('\tfprintf(fp, "# build_options: ${build_options}\\n");')
+	g.cov_declarations.writeln('\tfprintf(fp, "# build_options: ${cescape_nonascii(cestring(build_options))}\\n");')
 	g.cov_declarations.writeln('\tfprintf(fp, "meta,point,hits\\n");')
 	for k, cov in g.coverage_files {
 		nr_points := cov.points.len

From 729ecc9a5bb9e663ce9b0241bde3aca330ed540e Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sun, 26 May 2024 01:29:21 +0300
Subject: [PATCH 25/38] escape the paths and build options involved in coverage
 reports, when they are put in generated C or generated JSON files

---
 vlib/v/gen/c/coverage.v | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 530830ea3f87cf..26031bbd1876a7 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -54,15 +54,17 @@ fn (mut g Gen) write_coverage_stats() {
 	g.cov_declarations.writeln('\tchar cov_filename[2048];')
 	g.cov_declarations.writeln('\tchar *cov_dir = "${os.real_path(g.pref.coverage_dir)}";')
 	for _, mut cov in g.coverage_files {
-		metadata_coverage_fpath := os.join_path(coverage_meta_folder, '${cov.fhash}.txt')
+		metadata_coverage_fpath := os.join_path(coverage_meta_folder, '${cov.fhash}.json')
 		if os.exists(metadata_coverage_fpath) {
 			continue
 		}
 		mut fmeta := os.create(metadata_coverage_fpath) or { continue }
 		fmeta.writeln('{') or { continue }
-		fmeta.writeln('  "file": "${cov.file.path}", "fhash": "${cov.fhash}",') or { continue }
-		fmeta.writeln('  "v_version": "${version.full_v_version(true)}",') or { continue }
-		fmeta.writeln('  "build_options": "${cov.build_options}",') or { continue }
+		fmeta.writeln('  "file": "${jesc(os.real_path(cov.file.path))}", "fhash": "${jesc(cov.fhash)}",') or {
+			continue
+		}
+		fmeta.writeln('  "v_version": "${jesc(version.full_v_version(true))}",') or { continue }
+		fmeta.writeln('  "build_options": "${jesc(cov.build_options)}",') or { continue }
 		fmeta.writeln('  "npoints": ${cov.points.len},') or { continue }
 		fmeta.write_string('  "points": [  ') or { continue }
 		for idx, p in cov.points {
@@ -79,8 +81,8 @@ fn (mut g Gen) write_coverage_stats() {
 	g.cov_declarations.writeln('\tclock_gettime(CLOCK_MONOTONIC, &ts);')
 	g.cov_declarations.writeln('\tsnprintf(cov_filename, sizeof(cov_filename), "%s/vcounters_${counter_ulid}.%ld.%ld.csv", cov_dir, ts.tv_sec, ts.tv_nsec);')
 	g.cov_declarations.writeln('\tFILE *fp = fopen(cov_filename, "wb+");')
-	g.cov_declarations.writeln('\tfprintf(fp, "# path: ${g.pref.path}\\n");')
-	g.cov_declarations.writeln('\tfprintf(fp, "# build_options: ${cescape_nonascii(cestring(build_options))}\\n");')
+	g.cov_declarations.writeln('\tfprintf(fp, "# path: ${cesc(os.real_path(g.pref.path))}\\n");')
+	g.cov_declarations.writeln('\tfprintf(fp, "# build_options: ${cesc(build_options)}\\n");')
 	g.cov_declarations.writeln('\tfprintf(fp, "meta,point,hits\\n");')
 	for k, cov in g.coverage_files {
 		nr_points := cov.points.len
@@ -95,3 +97,11 @@ fn (mut g Gen) write_coverage_stats() {
 	g.cov_declarations.writeln('\tfclose(fp);')
 	g.cov_declarations.writeln('}')
 }
+
+fn cesc(s string) string {
+	return cescape_nonascii(cestring(s))
+}
+
+fn jesc(s string) string {
+	return escape_quotes(s)
+}

From f08eafb205aadaa4a50dd6cddc79b8230791193f Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sun, 26 May 2024 01:43:19 +0300
Subject: [PATCH 26/38] update copyright

---
 vlib/v/gen/c/coverage.v | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 26031bbd1876a7..0ea5fe60af34c0 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -1,4 +1,4 @@
-// Copyright (c) 2024 Felipe Pena. All rights reserved.
+// Copyright (c) 2024 Felipe Pena and Delyan Angelov. All rights reserved.
 // Use of this source code is governed by an MIT license
 // that can be found in the LICENSE file.
 module c

From 7f9c0d6f863b118d5d4b72c85e1d97dab7d2a089 Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sun, 26 May 2024 01:58:22 +0300
Subject: [PATCH 27/38] draft of `v cover` working with the updated .csv and
 .json coverage data

---
 cmd/tools/vcover/data.v                       |  34 +++
 cmd/tools/vcover/main.v                       | 203 ++++++++++++++++++
 cmd/tools/vcover/{vcover.v => reporting.v}    |  12 +-
 .../testdata/example2/runtime_condition.v     |  36 ++++
 .../example2/runtime_condition_test.v         |   5 +
 5 files changed, 280 insertions(+), 10 deletions(-)
 create mode 100644 cmd/tools/vcover/data.v
 create mode 100644 cmd/tools/vcover/main.v
 rename cmd/tools/vcover/{vcover.v => reporting.v} (86%)
 create mode 100644 cmd/tools/vcover/testdata/example2/runtime_condition.v
 create mode 100644 cmd/tools/vcover/testdata/example2/runtime_condition_test.v

diff --git a/cmd/tools/vcover/data.v b/cmd/tools/vcover/data.v
new file mode 100644
index 00000000000000..468cb754e81b78
--- /dev/null
+++ b/cmd/tools/vcover/data.v
@@ -0,0 +1,34 @@
+// Copyright (c) 2024 Felipe Pena and Delyan Angelov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+module main
+
+// vcounter_*.csv files contain counter lines in a CSV format. They can get quite large,
+// for big programs, since they contain all non zero coverage counters.
+// Their names are timestamp (rand.ulid + clock_gettime) based, to minimise the chance that parallel runs
+// will overwrite each other, but without the overhead of additional synchronisation/locks.
+struct CounterLine {
+mut:
+	file string // retrieved based on the loaded meta
+	line int    // retrieved based on the loaded meta
+	//
+	meta  string // A filename in the sibling meta/ folder, should exist, to match the value from this field. The filename is a hash of both the path and the used build options, to facilitate merging coverage data from different builds/programs
+	point int    // The index of a source point. Note that it is not a line number, but an index in the meta data file, keyed by the field `meta` above.
+	hits  u64    // How many times the coverage point was executed. Only counters that are != 0 are recorded.
+}
+
+// Source metadata files in meta/*.txt, contain JSON encoded fields (mappings from v source files to point line numbers).
+// Their names are a result of a hashing function, applied over both the source file name, and the build options.
+// This has several benefits:
+//   a) it makes sure, that the resulting path is normalised
+//   b) the meta data is deduplicated between runs that use the same source files
+//   c) coverage data from different runs can be merged by simply reusing the same -coverage folder,
+//      or by copy/pasting all files from 1 run, to the folder of another.
+struct MetaData {
+	file          string // V source file path
+	fhash         string // fhash is the name of the meta file
+	v_version     string // the V version, used to generate the coverage meta data file
+	build_options string // the build options for the program
+	npoints       int    // the number of stored coverage points
+	points        []int  // the line numbers corresponding to each point
+}
diff --git a/cmd/tools/vcover/main.v b/cmd/tools/vcover/main.v
new file mode 100644
index 00000000000000..6bec1f3e51b142
--- /dev/null
+++ b/cmd/tools/vcover/main.v
@@ -0,0 +1,203 @@
+// Copyright (c) 2024 Felipe Pena and Delyan Angelov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+module main
+
+import os
+import log
+import flag
+import json
+import arrays
+import encoding.csv
+
+// program options, storage etc
+struct Context {
+mut:
+	show_help          bool
+	show_hotspots      bool
+	show_percentages   bool
+	show_test_files    bool
+	use_absolute_paths bool
+	be_verbose         bool
+	filter             string
+	working_folder     string
+	//
+	targets            []string
+	meta               map[string]MetaData // aggregated meta data, read from all .json files
+	all_lines_per_file map[string][]int    // aggregated by load_meta
+	//
+	counters         map[string]u64 // incremented by process_target, based on each .csv file
+	lines_per_file   map[string]map[int]int // incremented by process_target, based on each .csv file
+	processed_points u64
+}
+
+const metadata_extension = '.json'
+const vcounter_glob_pattern = 'vcounters_*.csv'
+
+fn (mut ctx Context) load_meta(folder string) {
+	for mfile in os.walk_ext(folder, metadata_extension) {
+		content := os.read_file(mfile) or { '' }
+		meta := os.file_name(mfile.replace(metadata_extension, ''))
+		data := json.decode(MetaData, content) or {
+			log.error('${@METHOD} failed to load ${mfile}')
+			continue
+		}
+		ctx.meta[meta] = data
+		mut lines_per_file := ctx.all_lines_per_file[data.file]
+		lines_per_file << data.points
+		ctx.all_lines_per_file[data.file] = arrays.distinct(lines_per_file)
+	}
+}
+
+fn (mut ctx Context) post_process_all_metas() {
+	ctx.verbose('${@METHOD}')
+	for _, m in ctx.meta {
+		lines_per_file := ctx.all_lines_per_file[m.file]
+		for line in lines_per_file {
+			ctx.counters['${m.file}:${line}:'] = 0
+		}
+	}
+}
+
+fn (mut ctx Context) post_process_all_targets() {
+	ctx.verbose('${@METHOD}')
+	ctx.verbose('ctx.processed_points: ${ctx.processed_points}')
+}
+
+fn (ctx &Context) verbose(msg string) {
+	if ctx.be_verbose {
+		log.info(msg)
+	}
+}
+
+fn (mut ctx Context) process_target(tfile string) ! {
+	ctx.verbose('${@METHOD} ${tfile}')
+	mut reader := csv.new_reader_from_file(tfile)!
+	header := reader.read()!
+	if header != ['meta', 'point', 'hits'] {
+		return error('invalid header in .csv file')
+	}
+	for {
+		row := reader.read() or { break }
+		mut cline := CounterLine{
+			meta: row[0]
+			point: row[1].int()
+			hits: row[2].u64()
+		}
+		m := ctx.meta[cline.meta] or {
+			ctx.verbose('> skipping invalid meta: ${cline.meta} in file: ${cline.file}, csvfile: ${tfile}')
+			continue
+		}
+		cline.file = m.file
+		cline.line = m.points[cline.point] or {
+			ctx.verbose('> skipping invalid point: ${cline.point} in file: ${cline.file}, meta: ${cline.meta}, csvfile: ${tfile}')
+			continue
+		}
+		ctx.counters['${cline.file}:${cline.line}:'] += cline.hits
+		mut lines := ctx.lines_per_file[cline.file].move()
+		lines[cline.line]++
+		ctx.lines_per_file[cline.file] = lines.move()
+		// dump( ctx.lines_per_file[cline.meta][cline.point] )
+		ctx.processed_points++
+	}
+}
+
+fn (mut ctx Context) show_report() ! {
+	filters := ctx.filter.split(',').filter(it != '')
+	if ctx.show_hotspots {
+		for location, hits in ctx.counters {
+			if filters.len > 0 {
+				if !filters.any(location.contains(it)) {
+					continue
+				}
+			}
+			println('${hits:-8} ${location}')
+		}
+	}
+	if ctx.show_percentages {
+		for file, lines in ctx.lines_per_file {
+			if !ctx.show_test_files {
+				if file.ends_with('_test.v') || file.ends_with('_test.c.v') {
+					continue
+				}
+			}
+			if filters.len > 0 {
+				if !filters.any(file.contains(it)) {
+					continue
+				}
+			}
+			total_lines := ctx.all_lines_per_file[file].len
+			executed_points := lines.len
+			coverage_percent := 100.0 * f64(executed_points) / f64(total_lines)
+			mut final_path := normalize_path(file)
+			if !ctx.use_absolute_paths {
+				final_path = file.all_after_first('${ctx.working_folder}/')
+			}
+			println('${final_path:-80s} | ${executed_points:6} | ${total_lines:6} | ${coverage_percent:6.2f}%')
+		}
+	}
+}
+
+fn normalize_path(path string) string {
+	return path.replace(os.path_separator, '/')
+}
+
+fn main() {
+	mut ctx := Context{}
+	ctx.working_folder = normalize_path(os.real_path(os.getwd()))
+	mut fp := flag.new_flag_parser(os.args#[1..])
+	fp.application('v cover')
+	fp.version('0.0.2')
+	fp.description('Analyze & make reports, based on cover files, produced by running programs and tests, compiled with `-coverage folder/`')
+	fp.arguments_description('[folder1/ file2 ...]')
+	fp.skip_executable()
+	ctx.show_help = fp.bool('help', `h`, false, 'Show this help text.')
+	ctx.be_verbose = fp.bool('verbose', `v`, false, 'Be more verbose while processing the coverages.')
+	ctx.show_hotspots = fp.bool('hotspots', `H`, false, 'Show most frequently executed covered lines.')
+	ctx.show_percentages = fp.bool('percentages', `P`, true, 'Show coverage percentage per file.')
+	ctx.show_test_files = fp.bool('show_test_files', `S`, false, 'Show `_test.v` files as well (normally filtered).')
+	ctx.use_absolute_paths = fp.bool('absolute', `A`, false, 'Use absolute paths for all files, no matter the current folder. By default, files inside the current folder, are shown with a relative path.')
+	ctx.filter = fp.string('filter', `f`, '', 'Filter only the matching source path patterns.')
+	if ctx.show_help {
+		println(fp.usage())
+		exit(0)
+	}
+	targets := fp.finalize() or {
+		log.error(fp.usage())
+		exit(1)
+	}
+	ctx.verbose('Targets: ${targets}')
+	for t in targets {
+		if !os.exists(t) {
+			log.error('Skipping ${t}, since it does not exist')
+			continue
+		}
+		if os.is_dir(t) {
+			found_counter_files := os.glob('${t}/${vcounter_glob_pattern}')!
+			if found_counter_files.len == 0 {
+				log.error('Skipping ${t}, since there are 0 ${vcounter_glob_pattern} files in it')
+				continue
+			}
+			for counterfile in found_counter_files {
+				ctx.targets << counterfile
+				ctx.load_meta(t)
+			}
+		} else {
+			ctx.targets << t
+			ctx.load_meta(os.dir(t))
+		}
+	}
+	ctx.post_process_all_metas()
+	ctx.verbose('Final ctx.targets.len: ${ctx.targets.len}')
+	ctx.verbose('Final ctx.meta.len: ${ctx.meta.len}')
+	ctx.verbose('Final ctx.filter: ${ctx.filter}')
+	if ctx.targets.len == 0 {
+		log.error('0 cover targets')
+		exit(1)
+	}
+	for t in ctx.targets {
+		ctx.process_target(t)!
+	}
+	ctx.post_process_all_targets()
+	ctx.show_report()!
+}
diff --git a/cmd/tools/vcover/vcover.v b/cmd/tools/vcover/reporting.v
similarity index 86%
rename from cmd/tools/vcover/vcover.v
rename to cmd/tools/vcover/reporting.v
index de4e5086dc1ada..75aaf758e2ee44 100644
--- a/cmd/tools/vcover/vcover.v
+++ b/cmd/tools/vcover/reporting.v
@@ -1,15 +1,12 @@
-// Copyright (c) 2024 Felipe Pena. All rights reserved.
+// Copyright (c) 2024 Felipe Pena and Delyan Angelov. All rights reserved.
 // Use of this source code is governed by an MIT license
 // that can be found in the LICENSE file.
 module main
 
 import json
 import os
-import os.cmdline
 import arrays
 
-const tmp_dir = os.join_path(os.vtmp_dir(), 'cover')
-
 @[heap]
 struct VCoverData {
 	file string // file name
@@ -81,12 +78,7 @@ fn summarize_coverage(covfile string, mut covdata []&VCoverData) ! {
 	}
 }
 
-fn main() {
-	args := cmdline.options_after(os.args, ['cover'])
-	covfile := os.real_path(cmdline.option(args, '-file', ''))
-	covdir := os.real_path(cmdline.option(args, '-dir', ''))
-	filter := cmdline.option(args, '-filter', '')
-
+fn process_file_or_folder(filter string, covfile string, covdir string) ! {
 	if covfile != '' {
 		report_file(filter, covfile) or { println('Error: ${err}') }
 	} else if covdir != '' {
diff --git a/cmd/tools/vcover/testdata/example2/runtime_condition.v b/cmd/tools/vcover/testdata/example2/runtime_condition.v
new file mode 100644
index 00000000000000..f877089b249f3b
--- /dev/null
+++ b/cmd/tools/vcover/testdata/example2/runtime_condition.v
@@ -0,0 +1,36 @@
+module example2
+
+import os
+
+pub fn runtime_condition() int {
+	mut res := 0
+	branch := os.getenv('CONDITION')
+	if branch == '' {
+		return res
+	}
+	if branch.contains('1') {
+		res += 1
+	}
+	if branch.contains('2') {
+		res += 2
+	}
+	if branch.contains('3') {
+		res += 4
+	}
+	if branch.contains('4') {
+		res += 8
+	}
+	if branch.contains('5') {
+		res += 16
+	}
+	if branch.contains('6') {
+		res += 32
+	}
+	if branch.contains('7') {
+		res += 64
+	}
+	if branch.contains('8') {
+		res += 128
+	}
+	return res
+}
diff --git a/cmd/tools/vcover/testdata/example2/runtime_condition_test.v b/cmd/tools/vcover/testdata/example2/runtime_condition_test.v
new file mode 100644
index 00000000000000..a798f2b9d11686
--- /dev/null
+++ b/cmd/tools/vcover/testdata/example2/runtime_condition_test.v
@@ -0,0 +1,5 @@
+import example2
+
+fn test_runtime_condition() {
+	println(example2.runtime_condition())
+}

From f450a556f79f30899c77330297b8fbbb46af56b6 Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sun, 26 May 2024 04:47:14 +0300
Subject: [PATCH 28/38] Support relative locations in the --hotspots listing
 too

---
 cmd/tools/vcover/main.v | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/cmd/tools/vcover/main.v b/cmd/tools/vcover/main.v
index 6bec1f3e51b142..3340c9c1c0da49 100644
--- a/cmd/tools/vcover/main.v
+++ b/cmd/tools/vcover/main.v
@@ -111,7 +111,11 @@ fn (mut ctx Context) show_report() ! {
 					continue
 				}
 			}
-			println('${hits:-8} ${location}')
+			mut final_path := normalize_path(location)
+			if !ctx.use_absolute_paths {
+				final_path = location.all_after_first('${ctx.working_folder}/')
+			}
+			println('${hits:-8} ${final_path}')
 		}
 	}
 	if ctx.show_percentages {

From 19229fa23b59d793a1de5b1737a1b6ff5f4813fd Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sun, 26 May 2024 05:16:56 +0300
Subject: [PATCH 29/38] ci: fix `v build-tools`, since now `v cover` has
 multiple .v files.

---
 cmd/tools/vbuild-tools.v | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cmd/tools/vbuild-tools.v b/cmd/tools/vbuild-tools.v
index 1c04d7a277203f..cfd368595741ac 100644
--- a/cmd/tools/vbuild-tools.v
+++ b/cmd/tools/vbuild-tools.v
@@ -11,7 +11,7 @@ import v.util
 // should be compiled (v folder).
 // To implement that, these folders are initially skipped, then added
 // as a whole *after the testing.prepare_test_session call*.
-const tools_in_subfolders = ['vast', 'vcreate', 'vdoc', 'vpm', 'vsymlink', 'vvet', 'vwhere']
+const tools_in_subfolders = ['vast', 'vcreate', 'vdoc', 'vpm', 'vsymlink', 'vvet', 'vwhere', 'vcover']
 
 // non_packaged_tools are tools that should not be packaged with
 // prebuild versions of V, to keep the size smaller.

From 07499c8431d28f541637d4765479fa2e24c750e9 Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sun, 26 May 2024 12:13:56 +0300
Subject: [PATCH 30/38] ci: fix `./v -autofree -o v2 cmd/v` in the misc-tooling
 job

---
 vlib/v/gen/c/coverage.v | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 0ea5fe60af34c0..94810908bc9813 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -60,11 +60,13 @@ fn (mut g Gen) write_coverage_stats() {
 		}
 		mut fmeta := os.create(metadata_coverage_fpath) or { continue }
 		fmeta.writeln('{') or { continue }
-		fmeta.writeln('  "file": "${jesc(os.real_path(cov.file.path))}", "fhash": "${jesc(cov.fhash)}",') or {
-			continue
-		}
-		fmeta.writeln('  "v_version": "${jesc(version.full_v_version(true))}",') or { continue }
-		fmeta.writeln('  "build_options": "${jesc(cov.build_options)}",') or { continue }
+		jfilepath := jesc(os.real_path(cov.file.path))
+		jfhash := jesc(cov.fhash)
+		jversion := jesc(version.full_v_version(true))
+		jboptions := jesc(cov.build_options)
+		fmeta.writeln('  "file": "${jfilepath}", "fhash": "${jfhash}",') or { continue }
+		fmeta.writeln('  "v_version": "${jversion}",') or { continue }
+		fmeta.writeln('  "build_options": "${jboptions}",') or { continue }
 		fmeta.writeln('  "npoints": ${cov.points.len},') or { continue }
 		fmeta.write_string('  "points": [  ') or { continue }
 		for idx, p in cov.points {
@@ -81,8 +83,10 @@ fn (mut g Gen) write_coverage_stats() {
 	g.cov_declarations.writeln('\tclock_gettime(CLOCK_MONOTONIC, &ts);')
 	g.cov_declarations.writeln('\tsnprintf(cov_filename, sizeof(cov_filename), "%s/vcounters_${counter_ulid}.%ld.%ld.csv", cov_dir, ts.tv_sec, ts.tv_nsec);')
 	g.cov_declarations.writeln('\tFILE *fp = fopen(cov_filename, "wb+");')
-	g.cov_declarations.writeln('\tfprintf(fp, "# path: ${cesc(os.real_path(g.pref.path))}\\n");')
-	g.cov_declarations.writeln('\tfprintf(fp, "# build_options: ${cesc(build_options)}\\n");')
+	cprefpath := cesc(os.real_path(g.pref.path))
+	cboptions := cesc(build_options)
+	g.cov_declarations.writeln('\tfprintf(fp, "# path: ${cprefpath}\\n");')
+	g.cov_declarations.writeln('\tfprintf(fp, "# build_options: ${cboptions}\\n");')
 	g.cov_declarations.writeln('\tfprintf(fp, "meta,point,hits\\n");')
 	for k, cov in g.coverage_files {
 		nr_points := cov.points.len

From bceb1160ff577f9fa076dd21545525eab4f2ada9 Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sun, 26 May 2024 13:43:26 +0300
Subject: [PATCH 31/38] add more tests

---
 cmd/tools/vcover/cover_test.v              | 98 ++++++++++++++++++++++
 cmd/tools/vcover/testdata/simple/simple.v  | 26 ++++++
 cmd/tools/vcover/testdata/simple/t1_test.v |  7 ++
 cmd/tools/vcover/testdata/simple/t2_test.v |  7 ++
 cmd/tools/vcover/testdata/simple/v.mod     |  0
 5 files changed, 138 insertions(+)
 create mode 100644 cmd/tools/vcover/cover_test.v
 create mode 100644 cmd/tools/vcover/testdata/simple/simple.v
 create mode 100644 cmd/tools/vcover/testdata/simple/t1_test.v
 create mode 100644 cmd/tools/vcover/testdata/simple/t2_test.v
 create mode 100644 cmd/tools/vcover/testdata/simple/v.mod

diff --git a/cmd/tools/vcover/cover_test.v b/cmd/tools/vcover/cover_test.v
new file mode 100644
index 00000000000000..0ad71352344956
--- /dev/null
+++ b/cmd/tools/vcover/cover_test.v
@@ -0,0 +1,98 @@
+import os
+
+const vexe = @VEXE
+const vroot = os.dir(vexe)
+const tfolder = os.join_path(os.vtmp_dir(), 'cover_test')
+
+fn testsuite_begin() {
+	os.chdir(vroot)!
+	os.rmdir_all(tfolder) or {}
+	os.mkdir(tfolder) or {}
+}
+
+fn testsuite_end() {
+	os.rmdir_all(tfolder) or {}
+}
+
+fn test_help() {
+	res := os.execute('${os.quoted_path(vexe)} cover -h')
+	assert res.exit_code == 0
+	assert res.output.contains('Usage: v cover')
+	assert res.output.contains('Description: Analyze & make reports')
+	assert res.output.contains('Options:')
+	assert res.output.contains('-h, --help                Show this help text.')
+	assert res.output.contains('-v, --verbose             Be more verbose while processing the coverages.')
+	assert res.output.contains('-H, --hotspots            Show most frequently executed covered lines.')
+	assert res.output.contains('-P, --percentages         Show coverage percentage per file.')
+	assert res.output.contains('-S, --show_test_files     Show `_test.v` files as well (normally filtered).')
+	assert res.output.contains('-A, --absolute            Use absolute paths for all files')
+}
+
+fn test_simple() {
+	t1 := os.join_path(tfolder, 't1')
+	t2 := os.join_path(tfolder, 't2')
+	t3 := os.join_path(tfolder, 't3')
+	assert !os.exists(t1)
+	assert !os.exists(t2)
+	assert !os.exists(t3)
+
+	r1 := os.execute('${os.quoted_path(vexe)} -coverage ${os.quoted_path(t1)} cmd/tools/vcover/testdata/simple/t1_test.v')
+	assert r1.exit_code == 0, r1.str()
+	assert r1.output.trim_space() == '10', r1.str()
+	assert os.exists(t1), t1
+	filter1 := os.execute('${os.quoted_path(vexe)} cover ${os.quoted_path(t1)} --filter vcover/testdata/simple/')
+	assert filter1.exit_code == 0, filter1.output
+	assert filter1.output.contains('cmd/tools/vcover/testdata/simple/simple.v')
+	assert filter1.output.trim_space().ends_with('|      4 |      9 |  44.44%'), filter1.output
+	hfilter1 := os.execute('${os.quoted_path(vexe)} cover ${os.quoted_path(t1)} --filter vcover/testdata/simple/ -H -P false')
+	assert hfilter1.exit_code == 0, hfilter1.output
+	assert !hfilter1.output.contains('%'), hfilter1.output
+	houtput1 := hfilter1.output.trim_space().split_into_lines()
+	zeros1 := houtput1.filter(it.starts_with('0 '))
+	nzeros1 := houtput1.filter(!it.starts_with('0 '))
+	assert zeros1.len > 0
+	assert zeros1.any(it.contains('simple.v:12')), zeros1.str()
+	assert zeros1.any(it.contains('simple.v:14')), zeros1.str()
+	assert zeros1.any(it.contains('simple.v:17')), zeros1.str()
+	assert zeros1.any(it.contains('simple.v:18')), zeros1.str()
+	assert zeros1.any(it.contains('simple.v:19')), zeros1.str()
+	assert nzeros1.len > 0
+	assert nzeros1.any(it.contains('simple.v:4')), nzeros1.str()
+	assert nzeros1.any(it.contains('simple.v:6')), nzeros1.str()
+	assert nzeros1.any(it.contains('simple.v:8')), nzeros1.str()
+	assert nzeros1.any(it.contains('simple.v:25')), nzeros1.str()
+
+	r2 := os.execute('${os.quoted_path(vexe)} -coverage ${os.quoted_path(t2)} cmd/tools/vcover/testdata/simple/t2_test.v')
+	assert r2.exit_code == 0, r2.str()
+	assert r2.output.trim_space() == '24', r2.str()
+	assert os.exists(t2), t2
+	filter2 := os.execute('${os.quoted_path(vexe)} cover ${os.quoted_path(t2)} --filter vcover/testdata/simple')
+	assert filter2.exit_code == 0, filter2.output
+	assert filter2.output.contains('cmd/tools/vcover/testdata/simple/simple.v')
+	assert filter2.output.trim_space().ends_with('|      6 |      9 |  66.67%'), filter2.output
+	hfilter2 := os.execute('${os.quoted_path(vexe)} cover ${os.quoted_path(t2)} --filter testdata/simple -H -P false')
+	assert hfilter2.exit_code == 0, hfilter2.output
+	assert !hfilter2.output.contains('%'), hfilter2.output
+	houtput2 := hfilter2.output.trim_space().split_into_lines()
+	zeros2 := houtput2.filter(it.starts_with('0 '))
+	nzeros2 := houtput2.filter(!it.starts_with('0 '))
+	assert zeros2.len > 0
+	assert zeros2.any(it.contains('simple.v:4')), zeros2.str()
+	assert zeros2.any(it.contains('simple.v:6')), zeros2.str()
+	assert zeros2.any(it.contains('simple.v:8')), zeros2.str()
+	assert nzeros2.len > 0
+	assert nzeros2.any(it.contains('simple.v:17')), nzeros2.str()
+	assert nzeros2.any(it.contains('simple.v:18')), nzeros2.str()
+	assert nzeros2.any(it.contains('simple.v:19')), nzeros2.str()
+	assert nzeros2.any(it.contains('simple.v:25')), nzeros2.str()
+
+	// Run both tests. The coverage should be combined and == 100%
+	r3 := os.execute('${os.quoted_path(vexe)} -coverage ${os.quoted_path(t3)} test cmd/tools/vcover/testdata/simple/')
+	assert r3.exit_code == 0, r3.str()
+	assert r3.output.trim_space().contains('Summary for all V _test.v files: 2 passed'), r3.str()
+	assert os.exists(t3), t3
+	filter3 := os.execute('${os.quoted_path(vexe)} cover ${os.quoted_path(t3)} --filter simple/')
+	assert filter3.exit_code == 0, filter3.str()
+	assert filter3.output.contains('cmd/tools/vcover/testdata/simple/simple.v'), filter3.str()
+	assert filter3.output.trim_space().match_glob('*cmd/tools/vcover/testdata/simple/simple.v *|      9 |      9 | 100.00%'), filter3.str()
+}
diff --git a/cmd/tools/vcover/testdata/simple/simple.v b/cmd/tools/vcover/testdata/simple/simple.v
new file mode 100644
index 00000000000000..72e0c353d565d6
--- /dev/null
+++ b/cmd/tools/vcover/testdata/simple/simple.v
@@ -0,0 +1,26 @@
+module simple
+
+pub fn sum() int {
+	mut res := 0
+	for i in 1 .. 5 {
+		res += i
+	}
+	return res
+}
+
+pub fn mul() int {
+	mut res := 1
+	for i in 1 .. 5 {
+		res *= i
+	}
+	// the lines here are just to introduce an asymmetry in the reported coverage lines
+	c := res * 2
+	_ := c * 10
+	return res
+}
+
+pub const a_const = f()
+
+fn f() int {
+	return 50 // this should be executed always
+}
diff --git a/cmd/tools/vcover/testdata/simple/t1_test.v b/cmd/tools/vcover/testdata/simple/t1_test.v
new file mode 100644
index 00000000000000..e4ce9691eb6009
--- /dev/null
+++ b/cmd/tools/vcover/testdata/simple/t1_test.v
@@ -0,0 +1,7 @@
+import simple
+
+fn test_sum() {
+	s := simple.sum()
+	assert s == 10
+	println(s)
+}
diff --git a/cmd/tools/vcover/testdata/simple/t2_test.v b/cmd/tools/vcover/testdata/simple/t2_test.v
new file mode 100644
index 00000000000000..c46c38fa6d8639
--- /dev/null
+++ b/cmd/tools/vcover/testdata/simple/t2_test.v
@@ -0,0 +1,7 @@
+import simple
+
+fn test_mul() {
+	m := simple.mul()
+	assert m == 24
+	println(m)
+}
diff --git a/cmd/tools/vcover/testdata/simple/v.mod b/cmd/tools/vcover/testdata/simple/v.mod
new file mode 100644
index 00000000000000..e69de29bb2d1d6

From 26f1b659327462a6a40584ddcc180d80bd97bd8e Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sun, 26 May 2024 13:44:57 +0300
Subject: [PATCH 32/38] fix `v test cmd/tools/`

---
 cmd/tools/vcover/cover_test.v | 1 +
 1 file changed, 1 insertion(+)

diff --git a/cmd/tools/vcover/cover_test.v b/cmd/tools/vcover/cover_test.v
index 0ad71352344956..6134714048b815 100644
--- a/cmd/tools/vcover/cover_test.v
+++ b/cmd/tools/vcover/cover_test.v
@@ -5,6 +5,7 @@ const vroot = os.dir(vexe)
 const tfolder = os.join_path(os.vtmp_dir(), 'cover_test')
 
 fn testsuite_begin() {
+	os.setenv('VCOLORS', 'never', true)
 	os.chdir(vroot)!
 	os.rmdir_all(tfolder) or {}
 	os.mkdir(tfolder) or {}

From 189d3ca796f35e4b9388c1f82b60949d4acf7fff Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sun, 26 May 2024 14:35:40 +0300
Subject: [PATCH 33/38] ci: fix `v -os windows -coverage folder file.v`
 failure, use GetTickCount/0 on windows and clock_gettime/2 everywhere else

---
 vlib/v/gen/c/coverage.v | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 94810908bc9813..e694261061e9d4 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -79,9 +79,20 @@ fn (mut g Gen) write_coverage_stats() {
 		fmeta.writeln('}') or { continue }
 		fmeta.close()
 	}
+	g.cov_declarations.writeln('\tlong int secs = 0;')
+	g.cov_declarations.writeln('\tlong int nsecs = 0;')
+	g.cov_declarations.writeln('\t#if defined(_WIN32)')
+	g.cov_declarations.writeln('\tlong int ticks_passed = GetTickCount();')
+	g.cov_declarations.writeln('\nsecs = ticks_passed / 1000;')
+	g.cov_declarations.writeln('\nnsecs = (ticks_passed % 1000) * 1000000;')
+	g.cov_declarations.writeln('\t#endif')
+	g.cov_declarations.writeln('\t#if !defined(_WIN32)')
 	g.cov_declarations.writeln('\tstruct timespec ts;')
 	g.cov_declarations.writeln('\tclock_gettime(CLOCK_MONOTONIC, &ts);')
-	g.cov_declarations.writeln('\tsnprintf(cov_filename, sizeof(cov_filename), "%s/vcounters_${counter_ulid}.%ld.%ld.csv", cov_dir, ts.tv_sec, ts.tv_nsec);')
+	g.cov_declarations.writeln('\tsecs = ts.tv_sec;')
+	g.cov_declarations.writeln('\nsecs = ts.tv_nsec;')
+	g.cov_declarations.writeln('\t#endif')
+	g.cov_declarations.writeln('\tsnprintf(cov_filename, sizeof(cov_filename), "%s/vcounters_${counter_ulid}.%07ld.%09ld.csv", cov_dir, secs, nsecs);')
 	g.cov_declarations.writeln('\tFILE *fp = fopen(cov_filename, "wb+");')
 	cprefpath := cesc(os.real_path(g.pref.path))
 	cboptions := cesc(build_options)

From dbfb62e4bd43f89c7bcc3ad8ebeaa3a796b307e3 Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sun, 26 May 2024 15:48:38 +0300
Subject: [PATCH 34/38] ci: use just os.walk_ext/2, instead of os.glob/1 (the
 windows implementation of os.glob is less well tested and differs from the
 unix one, unlike os.walk_ext/2)

---
 cmd/tools/vcover/main.v      |  2 +-
 cmd/tools/vcover/reporting.v | 91 ------------------------------------
 2 files changed, 1 insertion(+), 92 deletions(-)
 delete mode 100644 cmd/tools/vcover/reporting.v

diff --git a/cmd/tools/vcover/main.v b/cmd/tools/vcover/main.v
index 3340c9c1c0da49..8d2c0d91a09c76 100644
--- a/cmd/tools/vcover/main.v
+++ b/cmd/tools/vcover/main.v
@@ -177,7 +177,7 @@ fn main() {
 			continue
 		}
 		if os.is_dir(t) {
-			found_counter_files := os.glob('${t}/${vcounter_glob_pattern}')!
+			found_counter_files := os.walk_ext(t, '.csv')
 			if found_counter_files.len == 0 {
 				log.error('Skipping ${t}, since there are 0 ${vcounter_glob_pattern} files in it')
 				continue
diff --git a/cmd/tools/vcover/reporting.v b/cmd/tools/vcover/reporting.v
deleted file mode 100644
index 75aaf758e2ee44..00000000000000
--- a/cmd/tools/vcover/reporting.v
+++ /dev/null
@@ -1,91 +0,0 @@
-// Copyright (c) 2024 Felipe Pena and Delyan Angelov. All rights reserved.
-// Use of this source code is governed by an MIT license
-// that can be found in the LICENSE file.
-module main
-
-import json
-import os
-import arrays
-
-@[heap]
-struct VCoverData {
-	file string // file name
-mut:
-	hits   u64 // file coverage hits
-	points u64 // file counter
-}
-
-pub fn (covdata []&VCoverData) find(filename string) ?&VCoverData {
-	for data in covdata {
-		if data.file == filename {
-			return unsafe { data }
-		}
-	}
-	return none
-}
-
-pub fn (covdata []VCoverData) filter_files(filters []string, remove_test bool) []VCoverData {
-	mut arr := []VCoverData{}
-	for data in covdata {
-		if remove_test && data.file.ends_with('_test.v') {
-			continue
-		}
-		if filters.len == 0 || filters.any(data.file.contains(it)) {
-			arr << data
-		}
-	}
-	return arr
-}
-
-fn display_result(filter string, data []VCoverData) ! {
-	mut covdata := data.clone()
-	if filter != '' {
-		filters := filter.split(',')
-		covdata = covdata.filter_files(filters, true)
-		if covdata.len == 0 {
-			return error('No result found with such filter')
-		}
-	} else {
-		covdata = covdata.filter_files([], true)
-	}
-	hits := arrays.sum(covdata.map(it.hits))!
-	points := arrays.sum(covdata.map(it.points))!
-	for lineinfo in covdata {
-		println('${(f64(lineinfo.hits) / lineinfo.points) * 100:7.2f} | ${lineinfo.hits:4u} | ${lineinfo.points:4u} | ${lineinfo.file}')
-	}
-	println('Total coverage: ${covdata.len} files, ${(f64(hits) / points) * 100:.2f}% coverage')
-}
-
-fn report_file(filter string, covfile string) ! {
-	json_content := os.read_file(covfile)!
-	data := json.decode([]VCoverData, json_content)!
-	display_result(filter, data)!
-}
-
-fn summarize_coverage(covfile string, mut covdata []&VCoverData) ! {
-	json_content := os.read_file(covfile)!
-	data := json.decode([]VCoverData, json_content)!
-	for lineinfo in data {
-		if mut fileinfo := covdata.find(lineinfo.file) {
-			if fileinfo.hits < lineinfo.hits {
-				fileinfo.hits = lineinfo.hits
-			}
-		} else {
-			covdata << &VCoverData{
-				...lineinfo
-			}
-		}
-	}
-}
-
-fn process_file_or_folder(filter string, covfile string, covdir string) ! {
-	if covfile != '' {
-		report_file(filter, covfile) or { println('Error: ${err}') }
-	} else if covdir != '' {
-		mut sum_data := []&VCoverData{}
-		for coverfile in os.glob(covdir + '/vcover.*')! {
-			summarize_coverage(coverfile, mut sum_data)!
-		}
-		display_result(filter, sum_data.map(*it)) or { println('Error: ${err}') }
-	}
-}

From adf49d24e2b80b203c7e46572f26e7576ade5af3 Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Sun, 26 May 2024 15:43:18 -0300
Subject: [PATCH 35/38] fix

---
 vlib/v/gen/c/cgen.v     | 9 +--------
 vlib/v/gen/c/coverage.v | 4 ++++
 2 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index a1ae5829f528f4..6c9443d73ce76f 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -2096,14 +2096,7 @@ fn (mut g Gen) write_v_source_line_info_stmt(stmt ast.Stmt) {
 	g.write_v_source_line_info_pos(stmt.pos)
 	if g.inside_ternary == 0 && g.pref.is_coverage && !g.inside_for_c_stmt
 		&& stmt !in [ast.FnDecl, ast.ForCStmt, ast.ForInStmt, ast.ForStmt] {
-		if stmt is ast.ExprStmt {
-			if !g.inside_assign
-				&& stmt.expr !in [ast.CastExpr, ast.IndexExpr, ast.StringInterLiteral, ast.StringLiteral, ast.Ident, ast.UnsafeExpr] {
-				g.write_coverage_point(stmt.pos)
-			}
-		} else {
-			g.write_coverage_point(stmt.pos)
-		}
+		g.write_coverage_point(stmt.pos)
 	}
 }
 
diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index e694261061e9d4..34fbcacb15c405 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -38,7 +38,11 @@ fn (mut g Gen) write_coverage_point(pos token.Pos) {
 		if curr_line !in curr_cov.points {
 			curr_cov.points << curr_line
 		}
+		stmt_str := g.go_before_last_stmt().trim_space()
+		g.empty_line = true
 		g.writeln('_v_cov[_v_cov_file_offset_${g.unique_file_path_hash}+${curr_cov.points.len - 1}]++;')
+		g.set_current_pos_as_last_stmt_pos()
+		g.write(stmt_str)
 	}
 }
 

From ec57f1035d455fda0873dc97fb88509b9855867d Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sun, 26 May 2024 22:21:12 +0300
Subject: [PATCH 36/38] ci: fix windows failure (unescaped path in the
 generated source)

---
 vlib/v/gen/c/coverage.v | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index 34fbcacb15c405..c19489981255c5 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -56,7 +56,8 @@ fn (mut g Gen) write_coverage_stats() {
 	g.cov_declarations.writeln('')
 	g.cov_declarations.writeln('void vprint_coverage_stats() {')
 	g.cov_declarations.writeln('\tchar cov_filename[2048];')
-	g.cov_declarations.writeln('\tchar *cov_dir = "${os.real_path(g.pref.coverage_dir)}";')
+	covdir := cesc(os.real_path(g.pref.coverage_dir))
+	g.cov_declarations.writeln('\tchar *cov_dir = "${covdir}";')
 	for _, mut cov in g.coverage_files {
 		metadata_coverage_fpath := os.join_path(coverage_meta_folder, '${cov.fhash}.json')
 		if os.exists(metadata_coverage_fpath) {

From a7c05704d079fced0f456acacf0e5998f18fdc06 Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sun, 26 May 2024 23:31:16 +0300
Subject: [PATCH 37/38] ci: normalise paths on windows to the unix ones for
 uniformity and consistent behaviour of the tests

---
 cmd/tools/vcover/cover_test.v | 21 +++++++++++++--------
 cmd/tools/vcover/main.v       |  3 ++-
 vlib/v/gen/c/coverage.v       | 10 ++++++----
 3 files changed, 21 insertions(+), 13 deletions(-)

diff --git a/cmd/tools/vcover/cover_test.v b/cmd/tools/vcover/cover_test.v
index 6134714048b815..1a42dea112e334 100644
--- a/cmd/tools/vcover/cover_test.v
+++ b/cmd/tools/vcover/cover_test.v
@@ -29,21 +29,26 @@ fn test_help() {
 	assert res.output.contains('-A, --absolute            Use absolute paths for all files')
 }
 
+fn np(path string) string {
+	return path.replace('\\', '/')
+}
+
 fn test_simple() {
-	t1 := os.join_path(tfolder, 't1')
-	t2 := os.join_path(tfolder, 't2')
-	t3 := os.join_path(tfolder, 't3')
-	assert !os.exists(t1)
-	assert !os.exists(t2)
-	assert !os.exists(t3)
+	t1 := np(os.join_path(tfolder, 't1'))
+	t2 := np(os.join_path(tfolder, 't2'))
+	t3 := np(os.join_path(tfolder, 't3'))
+	assert !os.exists(t1), t1
+	assert !os.exists(t2), t2
+	assert !os.exists(t3), t3
 
 	r1 := os.execute('${os.quoted_path(vexe)} -coverage ${os.quoted_path(t1)} cmd/tools/vcover/testdata/simple/t1_test.v')
 	assert r1.exit_code == 0, r1.str()
 	assert r1.output.trim_space() == '10', r1.str()
 	assert os.exists(t1), t1
-	filter1 := os.execute('${os.quoted_path(vexe)} cover ${os.quoted_path(t1)} --filter vcover/testdata/simple/')
+	cmd := '${os.quoted_path(vexe)} cover ${os.quoted_path(t1)} --filter vcover/testdata/simple/'
+	filter1 := os.execute(cmd)
 	assert filter1.exit_code == 0, filter1.output
-	assert filter1.output.contains('cmd/tools/vcover/testdata/simple/simple.v')
+	assert filter1.output.contains('cmd/tools/vcover/testdata/simple/simple.v'), filter1.output
 	assert filter1.output.trim_space().ends_with('|      4 |      9 |  44.44%'), filter1.output
 	hfilter1 := os.execute('${os.quoted_path(vexe)} cover ${os.quoted_path(t1)} --filter vcover/testdata/simple/ -H -P false')
 	assert hfilter1.exit_code == 0, hfilter1.output
diff --git a/cmd/tools/vcover/main.v b/cmd/tools/vcover/main.v
index 8d2c0d91a09c76..6d3c7ff954b4cb 100644
--- a/cmd/tools/vcover/main.v
+++ b/cmd/tools/vcover/main.v
@@ -35,7 +35,8 @@ const metadata_extension = '.json'
 const vcounter_glob_pattern = 'vcounters_*.csv'
 
 fn (mut ctx Context) load_meta(folder string) {
-	for mfile in os.walk_ext(folder, metadata_extension) {
+	for omfile in os.walk_ext(folder, metadata_extension) {
+		mfile := omfile.replace('\\', '/')
 		content := os.read_file(mfile) or { '' }
 		meta := os.file_name(mfile.replace(metadata_extension, ''))
 		data := json.decode(MetaData, content) or {
diff --git a/vlib/v/gen/c/coverage.v b/vlib/v/gen/c/coverage.v
index c19489981255c5..37ae9dd0012758 100644
--- a/vlib/v/gen/c/coverage.v
+++ b/vlib/v/gen/c/coverage.v
@@ -48,7 +48,8 @@ fn (mut g Gen) write_coverage_point(pos token.Pos) {
 
 fn (mut g Gen) write_coverage_stats() {
 	build_options := g.pref.build_options.join(' ')
-	coverage_meta_folder := os.join_path(g.pref.coverage_dir, 'meta')
+	coverage_dir := os.real_path(g.pref.coverage_dir).replace('\\', '/')
+	coverage_meta_folder := '${coverage_dir}/meta'
 	if !os.exists(coverage_meta_folder) {
 		os.mkdir_all(coverage_meta_folder) or {}
 	}
@@ -56,16 +57,17 @@ fn (mut g Gen) write_coverage_stats() {
 	g.cov_declarations.writeln('')
 	g.cov_declarations.writeln('void vprint_coverage_stats() {')
 	g.cov_declarations.writeln('\tchar cov_filename[2048];')
-	covdir := cesc(os.real_path(g.pref.coverage_dir))
+	covdir := cesc(coverage_dir)
 	g.cov_declarations.writeln('\tchar *cov_dir = "${covdir}";')
 	for _, mut cov in g.coverage_files {
-		metadata_coverage_fpath := os.join_path(coverage_meta_folder, '${cov.fhash}.json')
+		metadata_coverage_fpath := '${coverage_meta_folder}/${cov.fhash}.json'
+		filepath := os.real_path(cov.file.path).replace('\\', '/')
 		if os.exists(metadata_coverage_fpath) {
 			continue
 		}
 		mut fmeta := os.create(metadata_coverage_fpath) or { continue }
 		fmeta.writeln('{') or { continue }
-		jfilepath := jesc(os.real_path(cov.file.path))
+		jfilepath := jesc(filepath)
 		jfhash := jesc(cov.fhash)
 		jversion := jesc(version.full_v_version(true))
 		jboptions := jesc(cov.build_options)

From 9f34dec32b5eeb1effb5a4e55a4ba14ade0917f8 Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Mon, 27 May 2024 08:55:16 -0300
Subject: [PATCH 38/38] fix case where assert breaks

---
 vlib/v/gen/c/cgen.v | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index 586037a9a1e612..eebc54d07c9ce5 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -2096,7 +2096,13 @@ fn (mut g Gen) write_v_source_line_info_stmt(stmt ast.Stmt) {
 	g.write_v_source_line_info_pos(stmt.pos)
 	if g.inside_ternary == 0 && g.pref.is_coverage && !g.inside_for_c_stmt
 		&& stmt !in [ast.FnDecl, ast.ForCStmt, ast.ForInStmt, ast.ForStmt] {
-		g.write_coverage_point(stmt.pos)
+		if stmt is ast.AssertStmt {
+			if stmt.expr !in [ast.InfixExpr, ast.MatchExpr] {
+				g.write_coverage_point(stmt.pos)
+			}
+		} else {
+			g.write_coverage_point(stmt.pos)
+		}
 	}
 }