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// 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.
// Verify that switch statements with duplicate cases are detected by the compiler.
// Does not compile.
package main
import "fmt"
func f0(x int) {
switch x {
case 0:
case 0: // ERROR "duplicate case 0 in switch"
}
switch x {
case 0:
case int(0): // ERROR "duplicate case 0 in switch"
}
}
func f1(x float32) {
switch x {
case 5:
case 5: // ERROR "duplicate case 5 in switch"
case 5.0: // ERROR "duplicate case 5 in switch"
}
}
func f2(s string) {
switch s {
case "":
case "": // ERROR "duplicate case .. in switch"
case "abc":
case "abc": // ERROR "duplicate case .abc. in switch"
}
}
func f3(e interface{}) {
switch e {
case 0:
case 0: // ERROR "duplicate case 0 in switch"
case int64(0):
case float32(10):
case float32(10): // ERROR "duplicate case float32\(10\) in switch"
case float64(10):
case float64(10): // ERROR "duplicate case float64\(10\) in switch"
}
}
func f4(e interface{}) {
switch e.(type) {
case int:
case int: // ERROR "duplicate case int in type switch"
case int64:
case error:
case error: // ERROR "duplicate case error in type switch"
case fmt.Stringer:
case fmt.Stringer: // ERROR "duplicate case fmt.Stringer in type switch"
case struct {
i int "tag1"
}:
case struct {
i int "tag2"
}:
case struct {
i int "tag1"
}: // ERROR "duplicate case struct { i int .tag1. } in type switch"
}
}
func f5(a [1]int) {
switch a {
case [1]int{0}:
case [1]int{0}: // OK -- see issue 15896
}
}
// Ensure duplicate const bool clauses are accepted.
func f6() int {
switch {
case 0 == 0:
return 0
case 1 == 1: // Intentionally OK, even though a duplicate of the above const true
return 1
}
return 2
}
// Ensure duplicates in ranges are detected (issue #17517).
func f7(a int) {
switch a {
case 0:
case 0, 1: // ERROR "duplicate case 0"
case 1, 2, 3, 4: // ERROR "duplicate case 1"
}
}
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