toml: add compliance to official toml-lang/toml-test@8bb8d9c (#26070)

Author: larpon

.github/workflows/download_full_toml_test_suites.sh

@@ -10,7 +10,7 @@ rm -rf vlib/toml/tests/testdata/iarna vlib/toml/tests/testdata/toml_rs vlib/toml
 git -C vlib/toml/tests/testdata/iarna checkout 1880b1a
 
 ./v retry -- git clone -n https://github.com/toml-lang/toml-test.git vlib/toml/tests/testdata/toml_lang
-git -C vlib/toml/tests/testdata/toml_lang checkout c6a78f1
+git -C vlib/toml/tests/testdata/toml_lang checkout 8bb8d9c
 
 # A few history notes of toml-rs (previously alexcrichton):
 #  commit 7f5472c the test-suite dir moves to the crates/ sub-directory

vlib/toml/checker/checker.v

@@ -405,6 +405,32 @@ fn (c &Checker) check_time(t ast.Time) ! {
 			' "${lit}" is not a valid RFC 3339 Time format string in ...${c.excerpt(t.pos)}...')
 	}
 
+	if parts.len > 1 {
+		// Offset
+		offset_parts := parts[1].split(':')
+		if offset_parts.len != 2 {
+			return error(@MOD + '.' + @STRUCT + '.' + @FN +
+				' "${parts[1]}" is not a valid RFC 3339 time offset specifier in ...${c.excerpt(t.pos)}...')
+		}
+		hh := offset_parts[0].int()
+		if hh < 0 || hh > 24 {
+			pos := token.Pos{
+				...t.pos
+				pos: t.pos.pos + check_length
+			}
+			return error(@MOD + '.' + @STRUCT + '.' + @FN +
+				' "${hh}" hour specifier in "${parts[1]}" should be between 00 and 24 in ...${c.excerpt(pos)}...')
+		}
+		mm := offset_parts[1].int()
+		if mm < 0 || mm > 59 {
+			pos := token.Pos{
+				...t.pos
+				pos: t.pos.pos + check_length
+			}
+			return error(@MOD + '.' + @STRUCT + '.' + @FN +
+				' "${mm}" second specifier in "${parts[1]}" should be between 00 and 59 in ...${c.excerpt(pos)}...')
+		}
+	}
 	// Simulate a time offset if it's missing then it can be checked. Already toml supports local time and rfc3339 don't.
 	mut has_time_offset := false
 	for ch in parts[0]#[8..] {

vlib/toml/tests/toml_lang_test.v

@@ -1,7 +1,7 @@
 // Instructions for developers:
 // The actual tests and data can be obtained by doing:
 // `git clone -n https://github.com/toml-lang/toml-test.git vlib/toml/tests/testdata/toml_lang`
-// `git -C vlib/toml/tests/testdata/toml_lang reset --hard c6a78f1
+// `git -C vlib/toml/tests/testdata/toml_lang reset --hard 8bb8d9c
 // See also the CI toml tests
 import os
 import toml