else value when switching on error set has

optional capture value which is subset.

see #769

1 files changed, 33 insertions, 1 deletions

diff --git a/test/stage1/behavior/switch.zig b/test/stage1/behavior/switch.zig
index 11ed935233..7b6540d852 100644
--- a/test/stage1/behavior/switch.zig
+++ b/test/stage1/behavior/switch.zig
@@ -1,4 +1,6 @@
-const expect = @import("std").testing.expect;
+const std = @import("std");
+const expect = std.testing.expect;
+const expectError = std.testing.expectError;
 
 test "switch with numbers" {
     testSwitchWithNumbers(13);
@@ -296,3 +298,33 @@ test "anon enum literal used in switch on union enum" {
         },
     }
 }
+
+test "else prong of switch on error set excludes other cases" {
+    const S = struct {
+        fn doTheTest() void {
+            expectError(error.C, bar());
+        }
+        const E = error{
+            A,
+            B,
+        } || E2;
+
+        const E2 = error{
+            C,
+            D,
+        };
+
+        fn foo() E!void {
+            return error.C;
+        }
+
+        fn bar() E2!void {
+            foo() catch |err| switch (err) {
+                error.A, error.B => {},
+                else => |e| return e,
+            };
+        }
+    };
+    S.doTheTest();
+    comptime S.doTheTest();
+}