1 // Copyright 2010 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 /* 6 7 Vet examines Go source code and reports suspicious constructs, such as Printf 8 calls whose arguments do not align with the format string. Vet uses heuristics 9 that do not guarantee all reports are genuine problems, but it can find errors 10 not caught by the compilers. 11 12 It can be invoked three ways: 13 14 By package, from the go tool: 15 go vet package/path/name 16 vets the package whose path is provided. 17 18 By files: 19 go tool vet source/directory/*.go 20 vets the files named, all of which must be in the same package. 21 22 By directory: 23 go tool vet source/directory 24 recursively descends the directory, vetting each package it finds. 25 26 Vet's exit code is 2 for erroneous invocation of the tool, 1 if a 27 problem was reported, and 0 otherwise. Note that the tool does not 28 check every possible problem and depends on unreliable heuristics 29 so it should be used as guidance only, not as a firm indicator of 30 program correctness. 31 32 By default all checks are performed. If any flags are explicitly set 33 to true, only those tests are run. Conversely, if any flag is 34 explicitly set to false, only those tests are disabled. 35 Thus -printf=true runs the printf check, -printf=false runs all checks 36 except the printf check. 37 38 Available checks: 39 40 Printf family 41 42 Flag: -printf 43 44 Suspicious calls to functions in the Printf family, including any functions 45 with these names, disregarding case: 46 Print Printf Println 47 Fprint Fprintf Fprintln 48 Sprint Sprintf Sprintln 49 Error Errorf 50 Fatal Fatalf 51 Log Logf 52 Panic Panicf Panicln 53 The -printfuncs flag can be used to redefine this list. 54 If the function name ends with an 'f', the function is assumed to take 55 a format descriptor string in the manner of fmt.Printf. If not, vet 56 complains about arguments that look like format descriptor strings. 57 58 It also checks for errors such as using a Writer as the first argument of 59 Printf. 60 61 Methods 62 63 Flag: -methods 64 65 Non-standard signatures for methods with familiar names, including: 66 Format GobEncode GobDecode MarshalJSON MarshalXML 67 Peek ReadByte ReadFrom ReadRune Scan Seek 68 UnmarshalJSON UnreadByte UnreadRune WriteByte 69 WriteTo 70 71 Struct tags 72 73 Flag: -structtags 74 75 Struct tags that do not follow the format understood by reflect.StructTag.Get. 76 Well-known encoding struct tags (json, xml) used with unexported fields. 77 78 Unkeyed composite literals 79 80 Flag: -composites 81 82 Composite struct literals that do not use the field-keyed syntax. 83 84 Assembly declarations 85 86 Flag: -asmdecl 87 88 Mismatches between assembly files and Go function declarations. 89 90 Useless assignments 91 92 Flag: -assign 93 94 Check for useless assignments. 95 96 Atomic mistakes 97 98 Flag: -atomic 99 100 Common mistaken usages of the sync/atomic package. 101 102 Boolean conditions 103 104 Flag: -bool 105 106 Mistakes involving boolean operators. 107 108 Build tags 109 110 Flag: -buildtags 111 112 Badly formed or misplaced +build tags. 113 114 Copying locks 115 116 Flag: -copylocks 117 118 Locks that are erroneously passed by value. 119 120 Nil function comparison 121 122 Flag: -nilfunc 123 124 Comparisons between functions and nil. 125 126 Range loop variables 127 128 Flag: -rangeloops 129 130 Incorrect uses of range loop variables in closures. 131 132 Unreachable code 133 134 Flag: -unreachable 135 136 Unreachable code. 137 138 Shadowed variables 139 140 Flag: -shadow=false (experimental; must be set explicitly) 141 142 Variables that may have been unintentionally shadowed. 143 144 Misuse of unsafe Pointers 145 146 Flag: -unsafeptr 147 148 Likely incorrect uses of unsafe.Pointer to convert integers to pointers. 149 A conversion from uintptr to unsafe.Pointer is invalid if it implies that 150 there is a uintptr-typed word in memory that holds a pointer value, 151 because that word will be invisible to stack copying and to the garbage 152 collector. 153 154 Unused result of certain function calls 155 156 Flag: -unusedresult 157 158 Calls to well-known functions and methods that return a value that is 159 discarded. By default, this includes functions like fmt.Errorf and 160 fmt.Sprintf and methods like String and Error. The flags -unusedfuncs 161 and -unusedstringmethods control the set. 162 163 Shifts 164 165 Flag: -shift 166 167 Shifts equal to or longer than the variable's length. 168 169 Other flags 170 171 These flags configure the behavior of vet: 172 173 -all (default true) 174 Check everything; disabled if any explicit check is requested. 175 -v 176 Verbose mode 177 -printfuncs 178 A comma-separated list of print-like functions to supplement the 179 standard list. Each entry is in the form Name:N where N is the 180 zero-based argument position of the first argument involved in the 181 print: either the format or the first print argument for non-formatted 182 prints. For example, if you have Warn and Warnf functions that 183 take an io.Writer as their first argument, like Fprintf, 184 -printfuncs=Warn:1,Warnf:1 185 For more information, see the discussion of the -printf flag. 186 -shadowstrict 187 Whether to be strict about shadowing; can be noisy. 188 -test 189 For testing only: sets -all and -shadow. 190 */ 191 package main // import "golang.org/x/tools/cmd/vet" 192
