go source for verification 2026-05-22

test/fixedbugs/issue15898.go

@@ -0,0 +1,18 @@
+// errorcheck
+
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+func f(e interface{}) {
+	switch e.(type) {
+	case nil, nil: // ERROR "multiple nil cases in type switch|duplicate type in switch|duplicate case nil in type switch"
+	}
+
+	switch e.(type) {
+	case nil:
+	case nil: // ERROR "multiple nil cases in type switch|duplicate type in switch|duplicate case nil in type switch"
+	}
+}