cgen: allow alias types to be iterated if parent type has next method (fix #24890) (#24894)

Delta456 · web-flow · commit e2434a825684 · 2025-07-14T09:49:30.000+03:00
diff --git a/vlib/v/gen/c/for.v b/vlib/v/gen/c/for.v
@@ -422,7 +422,7 @@ fn (mut g Gen) for_in_stmt(node_ ast.ForInStmt) {
 			g.writeln('${field_accessor}str[${i}];')
 		}
 	} else if node.kind in [.struct, .interface] {
-		cond_type_sym := g.table.sym(node.cond_type)
+		cond_type_sym := g.table.final_sym(node.cond_type)
 		next_fn := cond_type_sym.find_method_with_generic_parent('next') or {
 			verror('`next` method not found')
 			return
diff --git a/vlib/v/tests/for_in_iterator_next_test.v b/vlib/v/tests/for_in_iterator_next_test.v
@@ -11,6 +11,8 @@ mut:
 	idx int
 }
 
+type AliasLineIterator = LineIterator
+
 pub fn (mut line_iterator LineIterator) next() ?string {
 	if line_iterator.idx >= line_iterator.lines.len {
 		return none
@@ -31,6 +33,12 @@ fn iterator_as_concrete_type() LineIterator {
 	}
 }
 
+fn iterator_as_alias_concrete_type() AliasLineIterator {
+	return AliasLineIterator(LineIterator{
+		lines: ['alias']
+	})
+}
+
 fn test_main() {
 	mut out := []string{}
 	for line in iterator_as_interface() {
@@ -64,4 +72,10 @@ fn test_main() {
 
 	assert out[4] == 'LINE: interface'
 	assert out[5] == 'LINE: concrete'
+
+	for _, line in iterator_as_alias_concrete_type() {
+		out << 'LINE: ${line}'
+	}
+
+	assert out[6] == 'LINE: alias'
 }

Original file line number	Diff line number	Diff line change
`@@ -422,7 +422,7 @@ fn (mut g Gen) for_in_stmt(node_ ast.ForInStmt) {`
`422`	`422`	`g.writeln('${field_accessor}str[${i}];')`
`423`	`423`	`}`
`424`	`424`	`} else if node.kind in [.struct, .interface] {`
`425`		`- cond_type_sym := g.table.sym(node.cond_type)`
	`425`	`+ cond_type_sym := g.table.final_sym(node.cond_type)`
`426`	`426`	`next_fn := cond_type_sym.find_method_with_generic_parent('next') or {`
`427`	`427`	verror('`next` method not found')
`428`	`428`	`return`