cgen: fix smartcast for struct fields in the match branches(fix #20167)…

… (#20171)
vlang · Dec 14, 2023 · f303679 · f303679
1 parent 0b12d64
commit f303679
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Showing 2 changed files with 24 additions and 2 deletions.
diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
@@ -2479,8 +2479,10 @@ fn (mut g Gen) expr_with_cast(expr ast.Expr, got_type_raw ast.Type, expected_typ
 					}
 				}
 			} else if expr is ast.SelectorExpr {
-				if _ := scope.find_struct_field(expr.expr.str(), expr.expr_type, expr.field_name) {
-					is_already_sum_type = true
+				if v := scope.find_struct_field(expr.expr.str(), expr.expr_type, expr.field_name) {
+					if v.smartcasts.len > 0 && unwrapped_expected_type == v.orig_type {
+						is_already_sum_type = true
+					}
 				}
 			}
 			if is_already_sum_type && !g.inside_return {

diff --git a/vlib/v/tests/match_smartcast_test.v b/vlib/v/tests/match_smartcast_test.v
@@ -97,3 +97,23 @@ fn test_match_mut_selector() {
 		}
 	}
 }
+
+// for issue 20167
+type Any_1 = f64 | int | string
+type Any_2 = int | string
+
+struct Struct {
+	field Any_2
+}
+
+fn test_branches_return_struct_field() {
+	any_2 := Struct{Any_2(42)}
+	m := {
+		'item1': Any_1('')
+		'item2': match any_2.field {
+			string { any_2.field }
+			int { any_2.field }
+		}
+	}
+	assert m['item2']! == Any_1(42)
+}