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	For #55326 Change-Id: I3d0ff7f820f7b2009d1b226abf701b2337fe8cbc Reviewed-on: https://go-review.googlesource.com/c/go/+/432635 TryBot-Result: Gopher Robot <gobot@golang.org> Auto-Submit: Robert Griesemer <gri@google.com> Run-TryBot: Robert Griesemer <gri@google.com> Reviewed-by: Robert Findley <rfindley@google.com> Run-TryBot: xie cui <523516579@qq.com> Reviewed-by: Robert Griesemer <gri@google.com>
		
			
				
	
	
		
			46 lines
		
	
	
	
		
			1.1 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			46 lines
		
	
	
	
		
			1.1 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
// errorcheck
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// Copyright 2016 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// Check the compiler's switch handling that happens
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// at typechecking time.
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// This must be separate from other checks,
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// because errors during typechecking
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// prevent other errors from being discovered.
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package main
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// Verify that type switch statements with impossible cases are detected by the compiler.
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func f0(e error) {
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	switch e.(type) {
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	case int: // ERROR "impossible type switch case: (int\n\t)?e \(.*type error\) cannot have dynamic type int \(missing method Error\)"
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	}
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}
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// Verify that the compiler rejects multiple default cases.
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func f1(e interface{}) {
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	switch e {
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	default:
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	default: // ERROR "multiple defaults( in switch)?"
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	}
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	switch e.(type) {
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	default:
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	default: // ERROR "multiple defaults( in switch)?"
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	}
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}
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type I interface {
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	Foo()
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}
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type X int
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func (*X) Foo() {}
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func f2() {
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	var i I
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	switch i.(type) {
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	case X: // ERROR "impossible type switch case: (X\n\t)?i \(.*type I\) cannot have dynamic type X \(method Foo has pointer receiver\)"
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	}
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}
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