mirror of
https://github.com/golang/go
synced 2024-10-01 01:08:33 -06:00
331c428e76
Experimental feature. It's too noisy yet to be enabled by default,
so it must be enabled explicitly by
go tool vet -shadow *.go
or
go tool vet -shadow directory
(The go command does not know about the -shadow flag.)
Fixes golang/go#5634.
R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/10409047
55 lines
1.5 KiB
Go
55 lines
1.5 KiB
Go
// Copyright 2013 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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// This file contains tests for the shadowed variable checker.
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// Some of these errors are caught by the compiler (shadowed return parameters for example)
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// but are nonetheless useful tests.
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package testdata
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import "os"
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func ShadowRead(f *os.File, buf []byte) (err error) {
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var x int
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if f != nil {
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err := 3 // OK - different type.
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}
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if f != nil {
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_, err := f.Read(buf) // ERROR "declaration of err shadows declaration at testdata/shadow.go:13"
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if err != nil {
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return
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}
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i := 3 // OK
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_ = i
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}
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if f != nil {
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var _, err = f.Read(buf) // ERROR "declaration of err shadows declaration at testdata/shadow.go:13"
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if err != nil {
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return
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}
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}
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for i := 0; i < 10; i++ {
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i := i // OK: obviously intentional idiomatic redeclaration
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go func() {
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println(i)
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}()
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}
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var shadowTemp interface{}
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switch shadowTemp := shadowTemp.(type) { // OK: obviously intentional idiomatic redeclaration
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case int:
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println("OK")
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}
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var shadowTemp = shadowTemp // OK: obviously intentional idiomatic redeclaration
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if true {
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var f *os.File // OK because f is not mentioned later in the function.
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// The declaration of x is a shadow because x is mentioned below.
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var x int // ERROR "declaration of x shadows declaration at testdata/shadow.go:14"
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_ = x
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f = nil
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}
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// Use a couple of variables to trigger shadowing errors.
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_, _ = err, x
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return
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}
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