| 1 | // Copyright 2013 The Go Authors. All rights reserved. |
|---|---|
| 2 | // Use of this source code is governed by a BSD-style |
| 3 | // license that can be found in the LICENSE file. |
| 4 | |
| 5 | // This file contains tests for the shadowed variable checker. |
| 6 | // Some of these errors are caught by the compiler (shadowed return parameters for example) |
| 7 | // but are nonetheless useful tests. |
| 8 | |
| 9 | package a |
| 10 | |
| 11 | import "os" |
| 12 | |
| 13 | func ShadowRead(f *os.File, buf []byte) (err error) { |
| 14 | var x int |
| 15 | if f != nil { |
| 16 | err := 3 // OK - different type. |
| 17 | _ = err |
| 18 | } |
| 19 | if f != nil { |
| 20 | _, err := f.Read(buf) // want "declaration of .err. shadows declaration at line 13" |
| 21 | if err != nil { |
| 22 | return err |
| 23 | } |
| 24 | i := 3 // OK |
| 25 | _ = i |
| 26 | } |
| 27 | if f != nil { |
| 28 | x := one() // want "declaration of .x. shadows declaration at line 14" |
| 29 | var _, err = f.Read(buf) // want "declaration of .err. shadows declaration at line 13" |
| 30 | if x == 1 && err != nil { |
| 31 | return err |
| 32 | } |
| 33 | } |
| 34 | for i := 0; i < 10; i++ { |
| 35 | i := i // OK: obviously intentional idiomatic redeclaration |
| 36 | go func() { |
| 37 | println(i) |
| 38 | }() |
| 39 | } |
| 40 | var shadowTemp interface{} |
| 41 | switch shadowTemp := shadowTemp.(type) { // OK: obviously intentional idiomatic redeclaration |
| 42 | case int: |
| 43 | println("OK") |
| 44 | _ = shadowTemp |
| 45 | } |
| 46 | if shadowTemp := shadowTemp; true { // OK: obviously intentional idiomatic redeclaration |
| 47 | var f *os.File // OK because f is not mentioned later in the function. |
| 48 | // The declaration of x is a shadow because x is mentioned below. |
| 49 | var x int // want "declaration of .x. shadows declaration at line 14" |
| 50 | _, _, _ = x, f, shadowTemp |
| 51 | } |
| 52 | // Use a couple of variables to trigger shadowing errors. |
| 53 | _, _ = err, x |
| 54 | return |
| 55 | } |
| 56 | |
| 57 | func one() int { |
| 58 | return 1 |
| 59 | } |
| 60 | |
| 61 | // Must not complain with an internal error for the |
| 62 | // implicitly declared type switch variable v. |
| 63 | func issue26725(x interface{}) int { |
| 64 | switch v := x.(type) { |
| 65 | case int, int32: |
| 66 | if v, ok := x.(int); ok { |
| 67 | return v |
| 68 | } |
| 69 | case int64: |
| 70 | return int(v) |
| 71 | } |
| 72 | return 0 |
| 73 | } |
| 74 | |
| 75 | // Verify that implicitly declared variables from |
| 76 | // type switches are considered in shadowing analysis. |
| 77 | func shadowTypeSwitch(a interface{}) { |
| 78 | switch t := a.(type) { |
| 79 | case int: |
| 80 | { |
| 81 | t := 0 // want "declaration of .t. shadows declaration at line 78" |
| 82 | _ = t |
| 83 | } |
| 84 | _ = t |
| 85 | case uint: |
| 86 | { |
| 87 | t := uint(0) // OK because t is not mentioned later in this function |
| 88 | _ = t |
| 89 | } |
| 90 | } |
| 91 | } |
| 92 | |
| 93 | func shadowBlock() { |
| 94 | var a int |
| 95 | { |
| 96 | var a = 3 // want "declaration of .a. shadows declaration at line 94" |
| 97 | _ = a |
| 98 | } |
| 99 | _ = a |
| 100 | } |
| 101 |
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