From 721dbec2e4991a4b47d4e24e86996d7da8a39274 Mon Sep 17 00:00:00 2001
From: shove <shove@163.com>
Date: Sun, 23 Oct 2022 01:02:11 +0800
Subject: [PATCH] checker: fix missed check on the initialization of result
 struct fields (fix #16152) (#16153)

---
 vlib/v/checker/struct.v                            |  8 ++++++--
 .../tests/struct_field_optional_init_err.out       | 14 ++++++++++++++
 .../tests/struct_field_optional_init_err.vv        | 11 +++++++++++
 3 files changed, 31 insertions(+), 2 deletions(-)
 create mode 100644 vlib/v/checker/tests/struct_field_optional_init_err.out
 create mode 100644 vlib/v/checker/tests/struct_field_optional_init_err.vv

diff --git a/vlib/v/checker/struct.v b/vlib/v/checker/struct.v
index e16686e297..394d055f7c 100644
--- a/vlib/v/checker/struct.v
+++ b/vlib/v/checker/struct.v
@@ -87,7 +87,7 @@ pub fn (mut c Checker) struct_decl(mut node ast.StructDecl) {
 			if field.has_default_expr {
 				c.expected_type = field.typ
 				default_expr_type := c.expr(field.default_expr)
-				if !field.typ.has_flag(.optional) {
+				if !field.typ.has_flag(.optional) && !field.typ.has_flag(.result) {
 					c.check_expr_opt_call(field.default_expr, default_expr_type)
 				}
 				struct_sym.info.fields[i].default_expr_typ = default_expr_type
@@ -420,7 +420,7 @@ pub fn (mut c Checker) struct_init(mut node ast.StructInit) ast.Type {
 				if expr_type == ast.void_type {
 					c.error('`$field.expr` (no value) used as value', field.pos)
 				}
-				if !field_info.typ.has_flag(.optional) {
+				if !field_info.typ.has_flag(.optional) && !field.typ.has_flag(.result) {
 					expr_type = c.check_expr_opt_call(field.expr, expr_type)
 				}
 				expr_type_sym := c.table.sym(expr_type)
@@ -465,6 +465,10 @@ pub fn (mut c Checker) struct_init(mut node ast.StructInit) ast.Type {
 					c.error('field `$field_info.name` is optional, but initialization of optional fields currently unsupported',
 						field.pos)
 				}
+				if field_info.typ.has_flag(.result) {
+					c.error('field `$field_info.name` is result, but initialization of result fields currently unsupported',
+						field.pos)
+				}
 				if expr_type.is_ptr() && expected_type.is_ptr() {
 					if mut field.expr is ast.Ident {
 						if mut field.expr.obj is ast.Var {
diff --git a/vlib/v/checker/tests/struct_field_optional_init_err.out b/vlib/v/checker/tests/struct_field_optional_init_err.out
new file mode 100644
index 0000000000..88a9c125d2
--- /dev/null
+++ b/vlib/v/checker/tests/struct_field_optional_init_err.out
@@ -0,0 +1,14 @@
+vlib/v/checker/tests/struct_field_optional_init_err.vv:8:3: error: field `bar` is result, but initialization of result fields currently unsupported
+    6 | fn main() {
+    7 |     _ := Foo{
+    8 |         bar: 1
+      |         ~~~~~~
+    9 |         baz: 1
+   10 |     }
+vlib/v/checker/tests/struct_field_optional_init_err.vv:9:3: error: field `baz` is optional, but initialization of optional fields currently unsupported
+    7 |     _ := Foo{
+    8 |         bar: 1
+    9 |         baz: 1
+      |         ~~~~~~
+   10 |     }
+   11 | }
diff --git a/vlib/v/checker/tests/struct_field_optional_init_err.vv b/vlib/v/checker/tests/struct_field_optional_init_err.vv
new file mode 100644
index 0000000000..b04071e8e0
--- /dev/null
+++ b/vlib/v/checker/tests/struct_field_optional_init_err.vv
@@ -0,0 +1,11 @@
+struct Foo {
+	bar !int
+	baz ?int
+}
+
+fn main() {
+	_ := Foo{
+		bar: 1
+		baz: 1
+	}
+}