mirror of
https://github.com/golang/go
synced 2024-11-13 17:50:23 -07:00
34b563f447
Fixes #10561. Provides a better diagnostic message for failed type switch satisfaction in the case that a value receiver is being used in place of the pointer receiver that implements and satisfies the interface. Change-Id: If8c13ba13f2a8d81bf44bac7c3a66c12921ba921 Reviewed-on: https://go-review.googlesource.com/35235 Reviewed-by: Matthew Dempsky <mdempsky@google.com> Run-TryBot: Matthew Dempsky <mdempsky@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org>
47 lines
1.1 KiB
Go
47 lines
1.1 KiB
Go
// 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.
|
|
|
|
// Check the compiler's switch handling that happens
|
|
// at typechecking time.
|
|
// This must be separate from other checks,
|
|
// because errors during typechecking
|
|
// prevent other errors from being discovered.
|
|
|
|
package main
|
|
|
|
// Verify that type switch statements with impossible cases are detected by the compiler.
|
|
func f0(e error) {
|
|
switch e.(type) {
|
|
case int: // ERROR "impossible type switch case: e \(type error\) cannot have dynamic type int \(missing Error method\)"
|
|
}
|
|
}
|
|
|
|
// Verify that the compiler rejects multiple default cases.
|
|
func f1(e interface{}) {
|
|
switch e {
|
|
default:
|
|
default: // ERROR "multiple defaults in switch"
|
|
}
|
|
switch e.(type) {
|
|
default:
|
|
default: // ERROR "multiple defaults in switch"
|
|
}
|
|
}
|
|
|
|
type I interface {
|
|
Foo()
|
|
}
|
|
|
|
type X int
|
|
|
|
func (*X) Foo() {}
|
|
func f2() {
|
|
var i I
|
|
switch i.(type) {
|
|
case X: // ERROR "impossible type switch case: i \(type I\) cannot have dynamic type X \(Foo method has pointer receiver\)"
|
|
}
|
|
}
|