test: add tests for switch_block_err_union

1 files changed, 33 insertions, 0 deletions

diff --git a/test/cases/compile_errors/switch_expression-duplicate_error_prong.zig b/test/cases/compile_errors/switch_expression-duplicate_error_prong.zig
new file mode 100644
index 0000000000..bcebd25a58
--- /dev/null
+++ b/test/cases/compile_errors/switch_expression-duplicate_error_prong.zig
@@ -0,0 +1,33 @@
+fn f(n: Error!i32) i32 {
+    if (n) |x|
+        _ = x
+    else |e| switch (e) {
+        error.Foo => 1,
+        error.Bar => 2,
+        error.Baz => 3,
+        error.Foo => 2,
+    }
+}
+fn g(n: Error!i32) i32 {
+    n catch |e| switch (e) {
+        error.Foo => 1,
+        error.Bar => 2,
+        error.Baz => 3,
+        error.Foo => 2,
+    };
+}
+
+const Error = error{ Foo, Bar, Baz };
+
+export fn entry() usize {
+    return @sizeOf(@TypeOf(&f)) + @sizeOf(@TypeOf(&g));
+}
+
+// error
+// backend=stage2
+// target=native
+//
+// :8:9: error: duplicate switch value
+// :5:9: note: previous value here
+// :16:9: error: duplicate switch value
+// :13:9: note: previous value here