checker: enhance err msg for unknown types for comptime $for (#20057)

vlang · Dec 3, 2023 · f9f6ee7 · f9f6ee7
1 parent 582ec6e
commit f9f6ee7
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Showing 2 changed files with 6 additions and 5 deletions.
diff --git a/vlib/v/checker/comptime.v b/vlib/v/checker/comptime.v
@@ -255,7 +255,8 @@ fn (mut c Checker) comptime_for(mut node ast.ComptimeFor) {
 	typ := c.unwrap_generic(node.typ)
 	sym := c.table.final_sym(typ)
 	if sym.kind == .placeholder || typ.has_flag(.generic) {
-		c.error('unknown type `${sym.name}`', node.typ_pos)
+		c.error('\$for expects a type name to be used here, but ${sym.name} is not a type name',
+			node.typ_pos)
 	}
 	if node.kind == .fields {
 		if sym.kind in [.struct_, .interface_] {
@@ -268,7 +269,7 @@ fn (mut c Checker) comptime_for(mut node ast.ComptimeFor) {
 					fields = sym.info.fields.clone()
 				}
 				else {
-					c.error('comptime field lookup supports only structs and interfaces currently, and ${sym.name} is neither',
+					c.error('iterating over .fields is supported only for structs and interfaces, and ${sym.name} is neither',
 						node.typ_pos)
 					return
 				}

diff --git a/vlib/v/checker/tests/comptime_for.out b/vlib/v/checker/tests/comptime_for.out
@@ -11,20 +11,20 @@ vlib/v/checker/tests/comptime_for.vv:3:7: warning: unused variable: `f`
       |          ^
     4 |     $for f in T.fields {
     5 |         $if f.typ is Huh {}
-vlib/v/checker/tests/comptime_for.vv:2:12: error: unknown type `Huh`
+vlib/v/checker/tests/comptime_for.vv:2:12: error: $for expects a type name to be used here, but Huh is not a type name
     1 | fn unknown() {
     2 |     $for m in Huh.methods {}
       |               ~~~
     3 |     $for f in Huh.fields {}
     4 |     $for f in T.fields {
-vlib/v/checker/tests/comptime_for.vv:3:12: error: unknown type `Huh`
+vlib/v/checker/tests/comptime_for.vv:3:12: error: $for expects a type name to be used here, but Huh is not a type name
     1 | fn unknown() {
     2 |     $for m in Huh.methods {}
     3 |     $for f in Huh.fields {}
       |               ~~~
     4 |     $for f in T.fields {
     5 |         $if f.typ is Huh {}
-vlib/v/checker/tests/comptime_for.vv:4:12: error: unknown type `T`
+vlib/v/checker/tests/comptime_for.vv:4:12: error: $for expects a type name to be used here, but T is not a type name
     2 |     $for m in Huh.methods {}
     3 |     $for f in Huh.fields {}
     4 |     $for f in T.fields {