From f60d2855850801b3dfc37d08c876068c2f7b3266 Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Sat, 9 Nov 2024 08:46:59 -0300
Subject: [PATCH] checker: fix missing auto `from_string` type restriction
 (related to #22783) (#22803)

---
 vlib/v/checker/fn.v                            | 18 ++++++++++++++++++
 .../tests/from_string_on_non_enum_err.out      |  7 +++++++
 .../tests/from_string_on_non_enum_err.vv       | 14 ++++++++++++++
 3 files changed, 39 insertions(+)
 create mode 100644 vlib/v/checker/tests/from_string_on_non_enum_err.out
 create mode 100644 vlib/v/checker/tests/from_string_on_non_enum_err.vv

diff --git a/vlib/v/checker/fn.v b/vlib/v/checker/fn.v
index 6699ae1fb..a3641fe0b 100644
--- a/vlib/v/checker/fn.v
+++ b/vlib/v/checker/fn.v
@@ -1106,6 +1106,10 @@ fn (mut c Checker) fn_call(mut node ast.CallExpr, mut continue_check &bool) ast.
 					if !c.check_type_and_visibility(full_enum_name, idx, .enum, node.pos) {
 						return ast.void_type
 					}
+				} else {
+					if !c.check_type_sym_kind(full_enum_name, idx, .enum, node.pos) {
+						return ast.void_type
+					}
 				}
 			} else if !enum_name.contains('.') {
 				// find from another mods.
@@ -2066,6 +2070,20 @@ fn (mut c Checker) cast_to_fixed_array_ret(typ ast.Type, sym ast.TypeSymbol) ast
 	return typ
 }
 
+// checks if a symbol kind is an expected kind
+fn (mut c Checker) check_type_sym_kind(name string, type_idx int, expected_kind &ast.Kind, pos &token.Pos) bool {
+	mut sym := c.table.sym_by_idx(type_idx)
+	if sym.kind == .alias {
+		parent_type := (sym.info as ast.Alias).parent_type
+		sym = c.table.sym(parent_type)
+	}
+	if sym.kind != expected_kind {
+		c.error('expected ${expected_kind}, but `${name}` is ${sym.kind}', pos)
+		return false
+	}
+	return true
+}
+
 // checks if a type from another module is as expected and visible(`is_pub`)
 fn (mut c Checker) check_type_and_visibility(name string, type_idx int, expected_kind &ast.Kind, pos &token.Pos) bool {
 	mut sym := c.table.sym_by_idx(type_idx)
diff --git a/vlib/v/checker/tests/from_string_on_non_enum_err.out b/vlib/v/checker/tests/from_string_on_non_enum_err.out
new file mode 100644
index 000000000..5c13c1316
--- /dev/null
+++ b/vlib/v/checker/tests/from_string_on_non_enum_err.out
@@ -0,0 +1,7 @@
+vlib/v/checker/tests/from_string_on_non_enum_err.vv:12:2: error: expected enum, but `Foo` is struct
+   10 | 
+   11 | fn main() {
+   12 |     Foo.from_string('foo')
+      |     ~~~~~~~~~~~~~~~~~~~~~~
+   13 |     Bar.from_string('bar')
+   14 | }
diff --git a/vlib/v/checker/tests/from_string_on_non_enum_err.vv b/vlib/v/checker/tests/from_string_on_non_enum_err.vv
new file mode 100644
index 000000000..8d55bebae
--- /dev/null
+++ b/vlib/v/checker/tests/from_string_on_non_enum_err.vv
@@ -0,0 +1,14 @@
+struct Foo {
+	a int
+}
+
+struct Bar {
+	b int
+}
+
+fn Bar.from_string(a string) {}
+
+fn main() {
+	Foo.from_string('foo')
+	Bar.from_string('bar')
+}
-- 
2.39.5