From 550fa6803615aceb1c89feda2fe666d71afa26bc Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Sun, 8 Dec 2024 09:40:47 -0300
Subject: [PATCH] checker: fix selector generic or block (fix #23088) (#23102)

---
 vlib/v/checker/checker.v                        |  5 +++--
 .../tests/selector_generic_or_block_err.out     |  7 +++++++
 .../tests/selector_generic_or_block_err.vv      | 17 +++++++++++++++++
 3 files changed, 27 insertions(+), 2 deletions(-)
 create mode 100644 vlib/v/checker/tests/selector_generic_or_block_err.out
 create mode 100644 vlib/v/checker/tests/selector_generic_or_block_err.vv

diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index 699b21d72..631cfdab7 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -1720,9 +1720,10 @@ fn (mut c Checker) selector_expr(mut node ast.SelectorExpr) ast.Type {
 		}
 		node.typ = field.typ
 		if node.or_block.kind == .block {
-			c.expected_or_type = node.typ.clear_option_and_result()
+			unwrapped_typ := c.unwrap_generic(node.typ)
+			c.expected_or_type = unwrapped_typ.clear_option_and_result()
 			c.stmts_ending_with_expression(mut node.or_block.stmts, c.expected_or_type)
-			c.check_or_expr(node.or_block, node.typ, c.expected_or_type, node)
+			c.check_or_expr(node.or_block, unwrapped_typ, c.expected_or_type, node)
 			c.expected_or_type = ast.void_type
 		}
 		return field.typ
diff --git a/vlib/v/checker/tests/selector_generic_or_block_err.out b/vlib/v/checker/tests/selector_generic_or_block_err.out
new file mode 100644
index 000000000..20c11d86e
--- /dev/null
+++ b/vlib/v/checker/tests/selector_generic_or_block_err.out
@@ -0,0 +1,7 @@
+vlib/v/checker/tests/selector_generic_or_block_err.vv:7:24: error: wrong return type `string` in the `or {}` block, expected `int`
+    5 | 
+    6 | fn (f Foo[T]) str() string {
+    7 |     value := f.value or { 'this should be a checker error' }
+      |                           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+    8 |     return '${value}'
+    9 | }
diff --git a/vlib/v/checker/tests/selector_generic_or_block_err.vv b/vlib/v/checker/tests/selector_generic_or_block_err.vv
new file mode 100644
index 000000000..30db22c1b
--- /dev/null
+++ b/vlib/v/checker/tests/selector_generic_or_block_err.vv
@@ -0,0 +1,17 @@
+struct Foo[T] {
+pub:
+	value ?T
+}
+
+fn (f Foo[T]) str() string {
+	value := f.value or { 'this should be a checker error' }
+	return '${value}'
+}
+
+fn main() {
+	bar := Foo[int]{
+		value: 0
+	}
+
+	println(bar)
+}
-- 
2.39.5