1 // Copyright 2009 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.
5 // The testing package provides support for automated testing of Go packages.
6 // It is intended to be used in concert with the ``gotest'' utility, which automates
7 // execution of any function of the form
8 // func TestXxx(*testing.T)
9 // where Xxx can be any alphanumeric string (but the first letter must not be in
10 // [a-z]) and serves to identify the test routine.
11 // These TestXxx routines should be declared within the package they are testing.
13 // Functions of the form
14 // func BenchmarkXxx(*testing.B)
15 // are considered benchmarks, and are executed by gotest when the -benchmarks
18 // A sample benchmark function looks like this:
19 // func BenchmarkHello(b *testing.B) {
20 // for i := 0; i < b.N; i++ {
21 // fmt.Sprintf("hello")
24 // The benchmark package will vary b.N until the benchmark function lasts
25 // long enough to be timed reliably. The output
26 // testing.BenchmarkHello 500000 4076 ns/op
27 // means that the loop ran 500000 times at a speed of 4076 ns per loop.
29 // If a benchmark needs some expensive setup before running, the timer
31 // func BenchmarkBigLen(b *testing.B) {
35 // for i := 0; i < b.N; i++ {
48 // Report as tests are run; default is silent for success.
49 var chatty = flag.Bool("v", false, "verbose: print additional output")
50 var match = flag.String("match", "", "regular expression to select tests to run")
53 // Insert final newline if needed and tabs after internal newlines.
54 func tabify(s string) string {
56 if n > 0 && s[n-1] != '\n' {
60 for i := 0; i < n-1; i++ { // -1 to avoid final newline
62 return s[0:i+1] + "\t" + tabify(s[i+1:n])
68 // T is a type passed to Test functions to manage test state and support formatted test logs.
69 // Logs are accumulated during execution and dumped to standard error when done.
76 // Fail marks the Test function as having failed but continues execution.
77 func (t *T) Fail() { t.failed = true }
79 // Failed returns whether the Test function has failed.
80 func (t *T) Failed() bool { return t.failed }
82 // FailNow marks the Test function as having failed and stops its execution.
83 // Execution will continue at the next Test.
84 func (t *T) FailNow() {
90 // Log formats its arguments using default formatting, analogous to Print(),
91 // and records the text in the error log.
92 func (t *T) Log(args ...interface{}) { t.errors += "\t" + tabify(fmt.Sprintln(args...)) }
94 // Log formats its arguments according to the format, analogous to Printf(),
95 // and records the text in the error log.
96 func (t *T) Logf(format string, args ...interface{}) {
97 t.errors += "\t" + tabify(fmt.Sprintf(format, args...))
100 // Error is equivalent to Log() followed by Fail().
101 func (t *T) Error(args ...interface{}) {
106 // Errorf is equivalent to Logf() followed by Fail().
107 func (t *T) Errorf(format string, args ...interface{}) {
108 t.Logf(format, args...)
112 // Fatal is equivalent to Log() followed by FailNow().
113 func (t *T) Fatal(args ...interface{}) {
118 // Fatalf is equivalent to Logf() followed by FailNow().
119 func (t *T) Fatalf(format string, args ...interface{}) {
120 t.Logf(format, args...)
124 // An internal type but exported because it is cross-package; part of the implementation
126 type InternalTest struct {
131 func tRunner(t *T, test *InternalTest) {
136 // An internal function but exported because it is cross-package; part of the implementation
138 func Main(matchString func(pat, str string) (bool, os.Error), tests []InternalTest) {
142 println("testing: warning: no tests to run")
144 for i := 0; i < len(tests); i++ {
145 matched, err := matchString(*match, tests[i].Name)
147 println("invalid regexp for -match:", err.String())
154 println("=== RUN ", tests[i].Name)
158 go tRunner(t, &tests[i])
161 println("--- FAIL:", tests[i].Name)
165 println("--- PASS:", tests[i].Name)