gen: add type name to comp for (#10881)

vlib/builtin/builtin.v

@@ -108,6 +108,7 @@ pub:
 	args        []MethodArgs
 	return_type int
 	typ         int
+	type_name   string
 }
 
 // FieldData holds information about a field. Fields reside on structs.
@@ -119,6 +120,7 @@ pub:
 	is_mut    bool
 	is_shared bool
 	typ       int
+	type_name string
 }
 
 enum AttributeKind {

vlib/v/gen/c/comptime.v

@@ -459,6 +459,7 @@ fn (mut g Gen) comp_for(node ast.CompFor) {
 			ret_typ := method.return_type.idx()
 			g.writeln('\t${node.val_var}.typ = $styp;')
 			g.writeln('\t${node.val_var}.return_type = $ret_typ;')
+			g.writeln('\t${node.val_var}.type_name = _SLIT("${g.table.get_type_symbol(ret_typ).name}");')
 			//
 			g.comptime_var_type_map['${node.val_var}.return_type'] = ret_typ
 			g.comptime_var_type_map['${node.val_var}.typ'] = styp
@@ -502,6 +503,7 @@ fn (mut g Gen) comp_for(node ast.CompFor) {
 				// g.writeln('\t${node.val_var}.typ = _SLIT("$field_sym.name");')
 				styp := field.typ
 				g.writeln('\t${node.val_var}.typ = $styp;')
+				g.writeln('\t${node.val_var}.type_name = _SLIT("${g.table.get_type_symbol(styp).name}");')
 				g.writeln('\t${node.val_var}.is_pub = $field.is_pub;')
 				g.writeln('\t${node.val_var}.is_mut = $field.is_mut;')
 				g.writeln('\t${node.val_var}.is_shared = ${field.typ.has_flag(.shared_f)};')

vlib/v/tests/comptime_for_test.v

@@ -68,6 +68,7 @@ fn test_comptime_for_fields() {
 	$for field in App.fields {
 		println('  field: $field.name | ' + no_lines('$field'))
 		$if field.typ is string {
+			assert field.type_name == 'string'
 			assert field.name in ['a', 'b', 'g']
 		}
 		$if field.typ is f32 {