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	 a3dfcf51c6
			
		
	
	
		a3dfcf51c6
		
	
	
	
	
		
			
			Fixes #8927. Change-Id: I638cddd439dd2d4eeef5474118cfcbde0c8a5a43 Reviewed-on: https://go-review.googlesource.com/9632 Run-TryBot: David Chase <drchase@google.com> Reviewed-by: David Chase <drchase@google.com>
		
			
				
	
	
		
			74 lines
		
	
	
	
		
			2.2 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			74 lines
		
	
	
	
		
			2.2 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
| // errorcheck
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| 
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| // Copyright 2009 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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| 
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| // Verify that illegal assignments with both explicit and implicit conversions of literals are detected.
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| // Does not compile.
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| 
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| package main
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| 
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| import "unsafe"
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| 
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| // explicit conversion of constants
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| var x1 = string(1)
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| var x2 string = string(1)
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| var x3 = int(1.5)     // ERROR "convert|truncate"
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| var x4 int = int(1.5) // ERROR "convert|truncate"
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| var x5 = "a" + string(1)
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| var x6 = int(1e100)      // ERROR "overflow"
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| var x7 = float32(1e1000) // ERROR "overflow"
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| 
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| // unsafe.Pointer can only convert to/from uintptr
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| var _ = string(unsafe.Pointer(uintptr(65)))  // ERROR "convert"
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| var _ = float64(unsafe.Pointer(uintptr(65))) // ERROR "convert"
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| var _ = int(unsafe.Pointer(uintptr(65)))     // ERROR "convert"
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| 
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| // implicit conversions merit scrutiny
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| var s string
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| var bad1 string = 1  // ERROR "conver|incompatible|invalid|cannot"
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| var bad2 = s + 1     // ERROR "conver|incompatible|invalid"
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| var bad3 = s + 'a'   // ERROR "conver|incompatible|invalid"
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| var bad4 = "a" + 1   // ERROR "literals|incompatible|convert|invalid"
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| var bad5 = "a" + 'a' // ERROR "literals|incompatible|convert|invalid"
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| 
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| var bad6 int = 1.5       // ERROR "convert|truncate"
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| var bad7 int = 1e100     // ERROR "overflow"
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| var bad8 float32 = 1e200 // ERROR "overflow"
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| 
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| // but these implicit conversions are okay
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| var good1 string = "a"
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| var good2 int = 1.0
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| var good3 int = 1e9
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| var good4 float64 = 1e20
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| 
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| // explicit conversion of string is okay
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| var _ = []rune("abc")
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| var _ = []byte("abc")
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| 
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| // implicit is not
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| var _ []int = "abc"  // ERROR "cannot use|incompatible|invalid"
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| var _ []byte = "abc" // ERROR "cannot use|incompatible|invalid"
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| 
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| // named string is okay
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| type Tstring string
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| 
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| var ss Tstring = "abc"
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| var _ = []rune(ss)
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| var _ = []byte(ss)
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| 
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| // implicit is still not
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| var _ []rune = ss // ERROR "cannot use|incompatible|invalid"
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| var _ []byte = ss // ERROR "cannot use|incompatible|invalid"
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| 
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| // named slice is now ok
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| type Trune []rune
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| type Tbyte []byte
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| 
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| var _ = Trune("abc") // ok
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| var _ = Tbyte("abc") // ok
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| 
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| // implicit is still not
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| var _ Trune = "abc" // ERROR "cannot use|incompatible|invalid"
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| var _ Tbyte = "abc" // ERROR "cannot use|incompatible|invalid"
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