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   <h1>Package testing</h1>


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 			<dl>
 			<dd><code>import "testing"</code></dd>
 			</dl>
 			<dl>
 			<dd><a href="#overview" class="overviewLink">Overview</a></dd>
 			<dd><a href="#index">Index</a></dd>


 				<dd><a href="#subdirectories">Subdirectories</a></dd>

 			</dl>
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 				<p>
 Package testing provides support for automated testing of Go packages.
 It is intended to be used in concert with the &ldquo;go test&rdquo; command, which automates
 execution of any function of the form
 </p>
 <pre>func TestXxx(*testing.T)
 </pre>
 <p>
 where Xxx can be any alphanumeric string (but the first letter must not be in
 [a-z]) and serves to identify the test routine.
 These TestXxx routines should be declared within the package they are testing.
 </p>
 <p>
 Functions of the form
 </p>
 <pre>func BenchmarkXxx(*testing.B)
 </pre>
 <p>
 are considered benchmarks, and are executed by the &#34;go test&#34; command when
 the -test.bench flag is provided.
 </p>
 <p>
 A sample benchmark function looks like this:
 </p>
 <pre>func BenchmarkHello(b *testing.B) {
     for i := 0; i &lt; b.N; i++ {
         fmt.Sprintf(&#34;hello&#34;)
     }
 }
 </pre>
 <p>
 The benchmark package will vary b.N until the benchmark function lasts
 long enough to be timed reliably.  The output
 </p>
 <pre>testing.BenchmarkHello    10000000    282 ns/op
 </pre>
 <p>
 means that the loop ran 10000000 times at a speed of 282 ns per loop.
 </p>
 <p>
 If a benchmark needs some expensive setup before running, the timer
 may be stopped:
 </p>
 <pre>func BenchmarkBigLen(b *testing.B) {
     b.StopTimer()
     big := NewBig()
     b.StartTimer()
     for i := 0; i &lt; b.N; i++ {
         big.Len()
     }
 }
 </pre>
 <p>
 The package also runs and verifies example code. Example functions may
 include a concluding comment that begins with &#34;Output:&#34; and is compared with
 the standard output of the function when the tests are run, as in these
 examples of an example:
 </p>
 <pre>func ExampleHello() {
         fmt.Println(&#34;hello&#34;)
         // Output: hello
 }

 func ExampleSalutations() {
         fmt.Println(&#34;hello, and&#34;)
         fmt.Println(&#34;goodbye&#34;)
         // Output:
         // hello, and
         // goodbye
 }
 </pre>
 <p>
 Example functions without output comments are compiled but not executed.
 </p>
 <p>
 The naming convention to declare examples for a function F, a type T and
 method M on type T are:
 </p>
 <pre>func ExampleF() { ... }
 func ExampleT() { ... }
 func ExampleT_M() { ... }
 </pre>
 <p>
 Multiple example functions for a type/function/method may be provided by
 appending a distinct suffix to the name. The suffix must start with a
 lower-case letter.
 </p>
 <pre>func ExampleF_suffix() { ... }
 func ExampleT_suffix() { ... }
 func ExampleT_M_suffix() { ... }
 </pre>
 <p>
 The entire test file is presented as the example when it contains a single
 example function, at least one other function, type, variable, or constant
 declaration, and no test or benchmark functions.
 </p>

 			</div>
 		</div>


 		<h2 id="index">Index</h2>
 		<!-- Table of contents for API; must be named manual-nav to turn off auto nav. -->
 		<div id="manual-nav">
 			<dl>


 				<dd><a href="#Main">func Main(matchString func(pat, str string) (bool, error), tests []InternalTest, benchmarks []InternalBenchmark, examples []InternalExample)</a></dd>


 				<dd><a href="#RunBenchmarks">func RunBenchmarks(matchString func(pat, str string) (bool, error), benchmarks []InternalBenchmark)</a></dd>


 				<dd><a href="#RunExamples">func RunExamples(matchString func(pat, str string) (bool, error), examples []InternalExample) (ok bool)</a></dd>


 				<dd><a href="#RunTests">func RunTests(matchString func(pat, str string) (bool, error), tests []InternalTest) (ok bool)</a></dd>


 				<dd><a href="#Short">func Short() bool</a></dd>


 				<dd><a href="#B">type B</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#B.Error">func (c *B) Error(args ...interface{})</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#B.Errorf">func (c *B) Errorf(format string, args ...interface{})</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#B.Fail">func (c *B) Fail()</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#B.FailNow">func (c *B) FailNow()</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#B.Failed">func (c *B) Failed() bool</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#B.Fatal">func (c *B) Fatal(args ...interface{})</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#B.Fatalf">func (c *B) Fatalf(format string, args ...interface{})</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#B.Log">func (c *B) Log(args ...interface{})</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#B.Logf">func (c *B) Logf(format string, args ...interface{})</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#B.ResetTimer">func (b *B) ResetTimer()</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#B.SetBytes">func (b *B) SetBytes(n int64)</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#B.StartTimer">func (b *B) StartTimer()</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#B.StopTimer">func (b *B) StopTimer()</a></dd>


 				<dd><a href="#BenchmarkResult">type BenchmarkResult</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#Benchmark">func Benchmark(f func(b *B)) BenchmarkResult</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#BenchmarkResult.NsPerOp">func (r BenchmarkResult) NsPerOp() int64</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#BenchmarkResult.String">func (r BenchmarkResult) String() string</a></dd>


 				<dd><a href="#InternalBenchmark">type InternalBenchmark</a></dd>


 				<dd><a href="#InternalExample">type InternalExample</a></dd>


 				<dd><a href="#InternalTest">type InternalTest</a></dd>


 				<dd><a href="#T">type T</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#T.Error">func (c *T) Error(args ...interface{})</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#T.Errorf">func (c *T) Errorf(format string, args ...interface{})</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#T.Fail">func (c *T) Fail()</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#T.FailNow">func (c *T) FailNow()</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#T.Failed">func (c *T) Failed() bool</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#T.Fatal">func (c *T) Fatal(args ...interface{})</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#T.Fatalf">func (c *T) Fatalf(format string, args ...interface{})</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#T.Log">func (c *T) Log(args ...interface{})</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#T.Logf">func (c *T) Logf(format string, args ...interface{})</a></dd>


 					<dd>&nbsp; &nbsp; <a href="#T.Parallel">func (t *T) Parallel()</a></dd>


 		</dl>


 			<h4>Package files</h4>
 			<p>
 			<span style="font-size:90%">

 				<a href="/src/pkg/testing/benchmark.go">benchmark.go</a>

 				<a href="/src/pkg/testing/example.go">example.go</a>

 				<a href="/src/pkg/testing/testing.go">testing.go</a>

 			</span>
 			</p>


 			<h2 id="Main">func <a href="/src/pkg/testing/testing.go?s=9750:9890#L268">Main</a></h2>
 			<pre>func Main(matchString func(pat, str string) (bool, error), tests []InternalTest, benchmarks []InternalBenchmark, examples []InternalExample)</pre>
 			<p>
 An internal function but exported because it is cross-package; part of the implementation
 of the &#34;go test&#34; command.
 </p>


 			<h2 id="RunBenchmarks">func <a href="/src/pkg/testing/benchmark.go?s=5365:5464#L207">RunBenchmarks</a></h2>
 			<pre>func RunBenchmarks(matchString func(pat, str string) (bool, error), benchmarks []InternalBenchmark)</pre>
 			<p>
 An internal function but exported because it is cross-package; part of the implementation
 of the &#34;go test&#34; command.
 </p>


 			<h2 id="RunExamples">func <a href="/src/pkg/testing/example.go?s=314:417#L12">RunExamples</a></h2>
 			<pre>func RunExamples(matchString func(pat, str string) (bool, error), examples []InternalExample) (ok bool)</pre>


 			<h2 id="RunTests">func <a href="/src/pkg/testing/testing.go?s=10486:10580#L297">RunTests</a></h2>
 			<pre>func RunTests(matchString func(pat, str string) (bool, error), tests []InternalTest) (ok bool)</pre>


 			<h2 id="Short">func <a href="/src/pkg/testing/testing.go?s=4859:4876#L117">Short</a></h2>
 			<pre>func Short() bool</pre>
 			<p>
 Short reports whether the -test.short flag is set.
 </p>


 			<h2 id="B">type <a href="/src/pkg/testing/benchmark.go?s=743:872#L17">B</a></h2>
 			<pre>type B struct {
     N int
     <span class="comment">// contains filtered or unexported fields</span>
 }</pre>
 			<p>
 B is a type passed to Benchmark functions to manage benchmark
 timing and to specify the number of iterations to run.
 </p>


 				<h3 id="B.Error">func (*B) <a href="/src/pkg/testing/testing.go?s=8110:8153#L209">Error</a></h3>
 				<pre>func (c *B) Error(args ...interface{})</pre>
 				<p>
 Error is equivalent to Log() followed by Fail().
 </p>


 				<h3 id="B.Errorf">func (*B) <a href="/src/pkg/testing/testing.go?s=8253:8312#L215">Errorf</a></h3>
 				<pre>func (c *B) Errorf(format string, args ...interface{})</pre>
 				<p>
 Errorf is equivalent to Logf() followed by Fail().
 </p>


 				<h3 id="B.Fail">func (*B) <a href="/src/pkg/testing/testing.go?s=6270:6293#L163">Fail</a></h3>
 				<pre>func (c *B) Fail()</pre>
 				<p>
 Fail marks the function as having failed but continues execution.
 </p>


 				<h3 id="B.FailNow">func (*B) <a href="/src/pkg/testing/testing.go?s=6548:6574#L170">FailNow</a></h3>
 				<pre>func (c *B) FailNow()</pre>
 				<p>
 FailNow marks the function as having failed and stops its execution.
 Execution will continue at the next test or benchmark.
 </p>


 				<h3 id="B.Failed">func (*B) <a href="/src/pkg/testing/testing.go?s=6366:6396#L166">Failed</a></h3>
 				<pre>func (c *B) Failed() bool</pre>
 				<p>
 Failed returns whether the function has failed.
 </p>


 				<h3 id="B.Fatal">func (*B) <a href="/src/pkg/testing/testing.go?s=8420:8463#L221">Fatal</a></h3>
 				<pre>func (c *B) Fatal(args ...interface{})</pre>
 				<p>
 Fatal is equivalent to Log() followed by FailNow().
 </p>


 				<h3 id="B.Fatalf">func (*B) <a href="/src/pkg/testing/testing.go?s=8569:8628#L227">Fatalf</a></h3>
 				<pre>func (c *B) Fatalf(format string, args ...interface{})</pre>
 				<p>
 Fatalf is equivalent to Logf() followed by FailNow().
 </p>


 				<h3 id="B.Log">func (*B) <a href="/src/pkg/testing/testing.go?s=7763:7804#L202">Log</a></h3>
 				<pre>func (c *B) Log(args ...interface{})</pre>
 				<p>
 Log formats its arguments using default formatting, analogous to Println(),
 and records the text in the error log.
 </p>


 				<h3 id="B.Logf">func (*B) <a href="/src/pkg/testing/testing.go?s=7959:8016#L206">Logf</a></h3>
 				<pre>func (c *B) Logf(format string, args ...interface{})</pre>
 				<p>
 Logf formats its arguments according to the format, analogous to Printf(),
 and records the text in the error log.
 </p>


 				<h3 id="B.ResetTimer">func (*B) <a href="/src/pkg/testing/benchmark.go?s=1503:1527#L48">ResetTimer</a></h3>
 				<pre>func (b *B) ResetTimer()</pre>
 				<p>
 ResetTimer sets the elapsed benchmark time to zero.
 It does not affect whether the timer is running.
 </p>


 				<h3 id="B.SetBytes">func (*B) <a href="/src/pkg/testing/benchmark.go?s=1728:1757#L57">SetBytes</a></h3>
 				<pre>func (b *B) SetBytes(n int64)</pre>
 				<p>
 SetBytes records the number of bytes processed in a single operation.
 If this is called, the benchmark will report ns/op and MB/s.
 </p>


 				<h3 id="B.StartTimer">func (*B) <a href="/src/pkg/testing/benchmark.go?s=1047:1071#L29">StartTimer</a></h3>
 				<pre>func (b *B) StartTimer()</pre>
 				<p>
 StartTimer starts timing a test.  This function is called automatically
 before a benchmark starts, but it can also used to resume timing after
 a call to StopTimer.
 </p>


 				<h3 id="B.StopTimer">func (*B) <a href="/src/pkg/testing/benchmark.go?s=1288:1311#L39">StopTimer</a></h3>
 				<pre>func (b *B) StopTimer()</pre>
 				<p>
 StopTimer stops timing a test.  This can be used to pause the timer
 while performing complex initialization that you don&#39;t
 want to measure.
 </p>


 			<h2 id="BenchmarkResult">type <a href="/src/pkg/testing/benchmark.go?s=4206:4391#L165">BenchmarkResult</a></h2>
 			<pre>type BenchmarkResult struct {
     N     int           <span class="comment">// The number of iterations.</span>
     T     time.Duration <span class="comment">// The total time taken.</span>
     Bytes int64         <span class="comment">// Bytes processed in one iteration.</span>
 }</pre>
 			<p>
 The results of a benchmark run.
 </p>


 				<h3 id="Benchmark">func <a href="/src/pkg/testing/benchmark.go?s=7545:7589#L275">Benchmark</a></h3>
 				<pre>func Benchmark(f func(b *B)) BenchmarkResult</pre>
 				<p>
 Benchmark benchmarks a single function. Useful for creating
 custom benchmarks that do not use the &#34;go test&#34; command.
 </p>


 				<h3 id="BenchmarkResult.NsPerOp">func (BenchmarkResult) <a href="/src/pkg/testing/benchmark.go?s=4393:4433#L171">NsPerOp</a></h3>
 				<pre>func (r BenchmarkResult) NsPerOp() int64</pre>


 				<h3 id="BenchmarkResult.String">func (BenchmarkResult) <a href="/src/pkg/testing/benchmark.go?s=4677:4717#L185">String</a></h3>
 				<pre>func (r BenchmarkResult) String() string</pre>


 			<h2 id="InternalBenchmark">type <a href="/src/pkg/testing/benchmark.go?s=555:618#L10">InternalBenchmark</a></h2>
 			<pre>type InternalBenchmark struct {
     Name string
     F    func(b *B)
 }</pre>
 			<p>
 An internal type but exported because it is cross-package; part of the implementation
 of the &#34;go test&#34; command.
 </p>


 			<h2 id="InternalExample">type <a href="/src/pkg/testing/example.go?s=236:312#L6">InternalExample</a></h2>
 			<pre>type InternalExample struct {
     Name   string
     F      func()
     Output string
 }</pre>


 			<h2 id="InternalTest">type <a href="/src/pkg/testing/testing.go?s=9065:9121#L241">InternalTest</a></h2>
 			<pre>type InternalTest struct {
     Name string
     F    func(*T)
 }</pre>
 			<p>
 An internal type but exported because it is cross-package; part of the implementation
 of the &#34;go test&#34; command.
 </p>


 			<h2 id="T">type <a href="/src/pkg/testing/testing.go?s=6070:6199#L156">T</a></h2>
 			<pre>type T struct {
     <span class="comment">// contains filtered or unexported fields</span>
 }</pre>
 			<p>
 T is a type passed to Test functions to manage test state and support formatted test logs.
 Logs are accumulated during execution and dumped to standard error when done.
 </p>


 				<h3 id="T.Error">func (*T) <a href="/src/pkg/testing/testing.go?s=8110:8153#L209">Error</a></h3>
 				<pre>func (c *T) Error(args ...interface{})</pre>
 				<p>
 Error is equivalent to Log() followed by Fail().
 </p>


 				<h3 id="T.Errorf">func (*T) <a href="/src/pkg/testing/testing.go?s=8253:8312#L215">Errorf</a></h3>
 				<pre>func (c *T) Errorf(format string, args ...interface{})</pre>
 				<p>
 Errorf is equivalent to Logf() followed by Fail().
 </p>


 				<h3 id="T.Fail">func (*T) <a href="/src/pkg/testing/testing.go?s=6270:6293#L163">Fail</a></h3>
 				<pre>func (c *T) Fail()</pre>
 				<p>
 Fail marks the function as having failed but continues execution.
 </p>


 				<h3 id="T.FailNow">func (*T) <a href="/src/pkg/testing/testing.go?s=6548:6574#L170">FailNow</a></h3>
 				<pre>func (c *T) FailNow()</pre>
 				<p>
 FailNow marks the function as having failed and stops its execution.
 Execution will continue at the next test or benchmark.
 </p>


 				<h3 id="T.Failed">func (*T) <a href="/src/pkg/testing/testing.go?s=6366:6396#L166">Failed</a></h3>
 				<pre>func (c *T) Failed() bool</pre>
 				<p>
 Failed returns whether the function has failed.
 </p>


 				<h3 id="T.Fatal">func (*T) <a href="/src/pkg/testing/testing.go?s=8420:8463#L221">Fatal</a></h3>
 				<pre>func (c *T) Fatal(args ...interface{})</pre>
 				<p>
 Fatal is equivalent to Log() followed by FailNow().
 </p>


 				<h3 id="T.Fatalf">func (*T) <a href="/src/pkg/testing/testing.go?s=8569:8628#L227">Fatalf</a></h3>
 				<pre>func (c *T) Fatalf(format string, args ...interface{})</pre>
 				<p>
 Fatalf is equivalent to Logf() followed by FailNow().
 </p>


 				<h3 id="T.Log">func (*T) <a href="/src/pkg/testing/testing.go?s=7763:7804#L202">Log</a></h3>
 				<pre>func (c *T) Log(args ...interface{})</pre>
 				<p>
 Log formats its arguments using default formatting, analogous to Println(),
 and records the text in the error log.
 </p>


 				<h3 id="T.Logf">func (*T) <a href="/src/pkg/testing/testing.go?s=7959:8016#L206">Logf</a></h3>
 				<pre>func (c *T) Logf(format string, args ...interface{})</pre>
 				<p>
 Logf formats its arguments according to the format, analogous to Printf(),
 and records the text in the error log.
 </p>


 				<h3 id="T.Parallel">func (*T) <a href="/src/pkg/testing/testing.go?s=8809:8831#L234">Parallel</a></h3>
 				<pre>func (t *T) Parallel()</pre>
 				<p>
 Parallel signals that this test is to be run in parallel with (and only with)
 other parallel tests in this CPU group.
 </p>


 		</div>


 		<h2 id="subdirectories">Subdirectories</h2>

 	<table class="dir">
 	<tr>
 	<th>Name</th>
 	<th>&nbsp;&nbsp;&nbsp;&nbsp;</th>
 	<th style="text-align: left; width: auto">Synopsis</th>
 	</tr>

 		<tr>
 		<td><a href="..">..</a></td>
 		</tr>


 			<tr>
 			<td class="name"><a href="iotest">iotest</a></td>
 			<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
 			<td style="width: auto">Package iotest implements Readers and Writers useful mainly for testing.</td>
 			</tr>


 			<tr>
 			<td class="name"><a href="quick">quick</a></td>
 			<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
 			<td style="width: auto">Package quick implements utility functions to help with black box testing.</td>
 			</tr>


 	</table>


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	<div id="plusone"><g:plusone size="small" annotation="none"></g:plusone></div>
	<h1>Package testing</h1>




	<div id="nav"></div>


	<!--
	Copyright 2009 The Go Authors. All rights reserved.
	Use of this source code is governed by a BSD-style
	license that can be found in the LICENSE file.
	-->


	<div id="short-nav">
	<dl>
	<dd><code>import "testing"</code></dd>
	</dl>
	<dl>
	<dd><a href="#overview" class="overviewLink">Overview</a></dd>
	<dd><a href="#index">Index</a></dd>


	<dd><a href="#subdirectories">Subdirectories</a></dd>

	</dl>
	</div>
	<!-- The package's Name is printed as title by the top-level template -->
	<div id="overview" class="toggleVisible">
	<div class="collapsed">
	<h2 class="toggleButton" title="Click to show Overview section">Overview ▹</h2>
	</div>
	<div class="expanded">
	<h2 class="toggleButton" title="Click to hide Overview section">Overview ▾</h2>
	<p>
	Package testing provides support for automated testing of Go packages.
	It is intended to be used in concert with the “go test” command, which automates
	execution of any function of the form
	</p>
	<pre>func TestXxx(*testing.T)
	</pre>
	<p>
	where Xxx can be any alphanumeric string (but the first letter must not be in
	[a-z]) and serves to identify the test routine.
	These TestXxx routines should be declared within the package they are testing.
	</p>
	<p>
	Functions of the form
	</p>
	<pre>func BenchmarkXxx(*testing.B)
	</pre>
	<p>
	are considered benchmarks, and are executed by the "go test" command when
	the -test.bench flag is provided.
	</p>
	<p>
	A sample benchmark function looks like this:
	</p>
	<pre>func BenchmarkHello(b *testing.B) {
	for i := 0; i < b.N; i++ {
	fmt.Sprintf("hello")
	}
	}
	</pre>
	<p>
	The benchmark package will vary b.N until the benchmark function lasts
	long enough to be timed reliably. The output
	</p>
	<pre>testing.BenchmarkHello 10000000 282 ns/op
	</pre>
	<p>
	means that the loop ran 10000000 times at a speed of 282 ns per loop.
	</p>
	<p>
	If a benchmark needs some expensive setup before running, the timer
	may be stopped:
	</p>
	<pre>func BenchmarkBigLen(b *testing.B) {
	b.StopTimer()
	big := NewBig()
	b.StartTimer()
	for i := 0; i < b.N; i++ {
	big.Len()
	}
	}
	</pre>
	<p>
	The package also runs and verifies example code. Example functions may
	include a concluding comment that begins with "Output:" and is compared with
	the standard output of the function when the tests are run, as in these
	examples of an example:
	</p>
	<pre>func ExampleHello() {
	fmt.Println("hello")
	// Output: hello
	}

	func ExampleSalutations() {
	fmt.Println("hello, and")
	fmt.Println("goodbye")
	// Output:
	// hello, and
	// goodbye
	}
	</pre>
	<p>
	Example functions without output comments are compiled but not executed.
	</p>
	<p>
	The naming convention to declare examples for a function F, a type T and
	method M on type T are:
	</p>
	<pre>func ExampleF() { ... }
	func ExampleT() { ... }
	func ExampleT_M() { ... }
	</pre>
	<p>
	Multiple example functions for a type/function/method may be provided by
	appending a distinct suffix to the name. The suffix must start with a
	lower-case letter.
	</p>
	<pre>func ExampleF_suffix() { ... }
	func ExampleT_suffix() { ... }
	func ExampleT_M_suffix() { ... }
	</pre>
	<p>
	The entire test file is presented as the example when it contains a single
	example function, at least one other function, type, variable, or constant
	declaration, and no test or benchmark functions.
	</p>

	</div>
	</div>


	<h2 id="index">Index</h2>
	<!-- Table of contents for API; must be named manual-nav to turn off auto nav. -->
	<div id="manual-nav">
	<dl>




	<dd><a href="#Main">func Main(matchString func(pat, str string) (bool, error), tests []InternalTest, benchmarks []InternalBenchmark, examples []InternalExample)</a></dd>


	<dd><a href="#RunBenchmarks">func RunBenchmarks(matchString func(pat, str string) (bool, error), benchmarks []InternalBenchmark)</a></dd>


	<dd><a href="#RunExamples">func RunExamples(matchString func(pat, str string) (bool, error), examples []InternalExample) (ok bool)</a></dd>


	<dd><a href="#RunTests">func RunTests(matchString func(pat, str string) (bool, error), tests []InternalTest) (ok bool)</a></dd>


	<dd><a href="#Short">func Short() bool</a></dd>



	<dd><a href="#B">type B</a></dd>



	<dd>    <a href="#B.Error">func (c *B) Error(args ...interface{})</a></dd>


	<dd>    <a href="#B.Errorf">func (c *B) Errorf(format string, args ...interface{})</a></dd>


	<dd>    <a href="#B.Fail">func (c *B) Fail()</a></dd>


	<dd>    <a href="#B.FailNow">func (c *B) FailNow()</a></dd>


	<dd>    <a href="#B.Failed">func (c *B) Failed() bool</a></dd>


	<dd>    <a href="#B.Fatal">func (c *B) Fatal(args ...interface{})</a></dd>


	<dd>    <a href="#B.Fatalf">func (c *B) Fatalf(format string, args ...interface{})</a></dd>


	<dd>    <a href="#B.Log">func (c *B) Log(args ...interface{})</a></dd>


	<dd>    <a href="#B.Logf">func (c *B) Logf(format string, args ...interface{})</a></dd>


	<dd>    <a href="#B.ResetTimer">func (b *B) ResetTimer()</a></dd>


	<dd>    <a href="#B.SetBytes">func (b *B) SetBytes(n int64)</a></dd>


	<dd>    <a href="#B.StartTimer">func (b *B) StartTimer()</a></dd>


	<dd>    <a href="#B.StopTimer">func (b *B) StopTimer()</a></dd>



	<dd><a href="#BenchmarkResult">type BenchmarkResult</a></dd>


	<dd>    <a href="#Benchmark">func Benchmark(f func(b *B)) BenchmarkResult</a></dd>



	<dd>    <a href="#BenchmarkResult.NsPerOp">func (r BenchmarkResult) NsPerOp() int64</a></dd>


	<dd>    <a href="#BenchmarkResult.String">func (r BenchmarkResult) String() string</a></dd>



	<dd><a href="#InternalBenchmark">type InternalBenchmark</a></dd>




	<dd><a href="#InternalExample">type InternalExample</a></dd>




	<dd><a href="#InternalTest">type InternalTest</a></dd>




	<dd><a href="#T">type T</a></dd>



	<dd>    <a href="#T.Error">func (c *T) Error(args ...interface{})</a></dd>


	<dd>    <a href="#T.Errorf">func (c *T) Errorf(format string, args ...interface{})</a></dd>


	<dd>    <a href="#T.Fail">func (c *T) Fail()</a></dd>


	<dd>    <a href="#T.FailNow">func (c *T) FailNow()</a></dd>


	<dd>    <a href="#T.Failed">func (c *T) Failed() bool</a></dd>


	<dd>    <a href="#T.Fatal">func (c *T) Fatal(args ...interface{})</a></dd>


	<dd>    <a href="#T.Fatalf">func (c *T) Fatalf(format string, args ...interface{})</a></dd>


	<dd>    <a href="#T.Log">func (c *T) Log(args ...interface{})</a></dd>


	<dd>    <a href="#T.Logf">func (c *T) Logf(format string, args ...interface{})</a></dd>


	<dd>    <a href="#T.Parallel">func (t *T) Parallel()</a></dd>



	</dl>




	<h4>Package files</h4>
	<p>
	<span style="font-size:90%">

	<a href="/src/pkg/testing/benchmark.go">benchmark.go</a>

	<a href="/src/pkg/testing/example.go">example.go</a>

	<a href="/src/pkg/testing/testing.go">testing.go</a>

	</span>
	</p>







	<h2 id="Main">func <a href="/src/pkg/testing/testing.go?s=9750:9890#L268">Main</a></h2>
	<pre>func Main(matchString func(pat, str string) (bool, error), tests []InternalTest, benchmarks []InternalBenchmark, examples []InternalExample)</pre>
	<p>
	An internal function but exported because it is cross-package; part of the implementation
	of the "go test" command.
	</p>





	<h2 id="RunBenchmarks">func <a href="/src/pkg/testing/benchmark.go?s=5365:5464#L207">RunBenchmarks</a></h2>
	<pre>func RunBenchmarks(matchString func(pat, str string) (bool, error), benchmarks []InternalBenchmark)</pre>
	<p>
	An internal function but exported because it is cross-package; part of the implementation
	of the "go test" command.
	</p>





	<h2 id="RunExamples">func <a href="/src/pkg/testing/example.go?s=314:417#L12">RunExamples</a></h2>
	<pre>func RunExamples(matchString func(pat, str string) (bool, error), examples []InternalExample) (ok bool)</pre>





	<h2 id="RunTests">func <a href="/src/pkg/testing/testing.go?s=10486:10580#L297">RunTests</a></h2>
	<pre>func RunTests(matchString func(pat, str string) (bool, error), tests []InternalTest) (ok bool)</pre>





	<h2 id="Short">func <a href="/src/pkg/testing/testing.go?s=4859:4876#L117">Short</a></h2>
	<pre>func Short() bool</pre>
	<p>
	Short reports whether the -test.short flag is set.
	</p>






	<h2 id="B">type <a href="/src/pkg/testing/benchmark.go?s=743:872#L17">B</a></h2>
	<pre>type B struct {
	N int
	<span class="comment">// contains filtered or unexported fields</span>
	}</pre>
	<p>
	B is a type passed to Benchmark functions to manage benchmark
	timing and to specify the number of iterations to run.
	</p>












	<h3 id="B.Error">func (*B) <a href="/src/pkg/testing/testing.go?s=8110:8153#L209">Error</a></h3>
	<pre>func (c *B) Error(args ...interface{})</pre>
	<p>
	Error is equivalent to Log() followed by Fail().
	</p>





	<h3 id="B.Errorf">func (*B) <a href="/src/pkg/testing/testing.go?s=8253:8312#L215">Errorf</a></h3>
	<pre>func (c *B) Errorf(format string, args ...interface{})</pre>
	<p>
	Errorf is equivalent to Logf() followed by Fail().
	</p>





	<h3 id="B.Fail">func (*B) <a href="/src/pkg/testing/testing.go?s=6270:6293#L163">Fail</a></h3>
	<pre>func (c *B) Fail()</pre>
	<p>
	Fail marks the function as having failed but continues execution.
	</p>





	<h3 id="B.FailNow">func (*B) <a href="/src/pkg/testing/testing.go?s=6548:6574#L170">FailNow</a></h3>
	<pre>func (c *B) FailNow()</pre>
	<p>
	FailNow marks the function as having failed and stops its execution.
	Execution will continue at the next test or benchmark.
	</p>





	<h3 id="B.Failed">func (*B) <a href="/src/pkg/testing/testing.go?s=6366:6396#L166">Failed</a></h3>
	<pre>func (c *B) Failed() bool</pre>
	<p>
	Failed returns whether the function has failed.
	</p>





	<h3 id="B.Fatal">func (*B) <a href="/src/pkg/testing/testing.go?s=8420:8463#L221">Fatal</a></h3>
	<pre>func (c *B) Fatal(args ...interface{})</pre>
	<p>
	Fatal is equivalent to Log() followed by FailNow().
	</p>





	<h3 id="B.Fatalf">func (*B) <a href="/src/pkg/testing/testing.go?s=8569:8628#L227">Fatalf</a></h3>
	<pre>func (c *B) Fatalf(format string, args ...interface{})</pre>
	<p>
	Fatalf is equivalent to Logf() followed by FailNow().
	</p>





	<h3 id="B.Log">func (*B) <a href="/src/pkg/testing/testing.go?s=7763:7804#L202">Log</a></h3>
	<pre>func (c *B) Log(args ...interface{})</pre>
	<p>
	Log formats its arguments using default formatting, analogous to Println(),
	and records the text in the error log.
	</p>





	<h3 id="B.Logf">func (*B) <a href="/src/pkg/testing/testing.go?s=7959:8016#L206">Logf</a></h3>
	<pre>func (c *B) Logf(format string, args ...interface{})</pre>
	<p>
	Logf formats its arguments according to the format, analogous to Printf(),
	and records the text in the error log.
	</p>





	<h3 id="B.ResetTimer">func (*B) <a href="/src/pkg/testing/benchmark.go?s=1503:1527#L48">ResetTimer</a></h3>
	<pre>func (b *B) ResetTimer()</pre>
	<p>
	ResetTimer sets the elapsed benchmark time to zero.
	It does not affect whether the timer is running.
	</p>





	<h3 id="B.SetBytes">func (*B) <a href="/src/pkg/testing/benchmark.go?s=1728:1757#L57">SetBytes</a></h3>
	<pre>func (b *B) SetBytes(n int64)</pre>
	<p>
	SetBytes records the number of bytes processed in a single operation.
	If this is called, the benchmark will report ns/op and MB/s.
	</p>





	<h3 id="B.StartTimer">func (*B) <a href="/src/pkg/testing/benchmark.go?s=1047:1071#L29">StartTimer</a></h3>
	<pre>func (b *B) StartTimer()</pre>
	<p>
	StartTimer starts timing a test. This function is called automatically
	before a benchmark starts, but it can also used to resume timing after
	a call to StopTimer.
	</p>





	<h3 id="B.StopTimer">func (*B) <a href="/src/pkg/testing/benchmark.go?s=1288:1311#L39">StopTimer</a></h3>
	<pre>func (b *B) StopTimer()</pre>
	<p>
	StopTimer stops timing a test. This can be used to pause the timer
	while performing complex initialization that you don't
	want to measure.
	</p>







	<h2 id="BenchmarkResult">type <a href="/src/pkg/testing/benchmark.go?s=4206:4391#L165">BenchmarkResult</a></h2>
	<pre>type BenchmarkResult struct {
	N int <span class="comment">// The number of iterations.</span>
	T time.Duration <span class="comment">// The total time taken.</span>
	Bytes int64 <span class="comment">// Bytes processed in one iteration.</span>
	}</pre>
	<p>
	The results of a benchmark run.
	</p>










	<h3 id="Benchmark">func <a href="/src/pkg/testing/benchmark.go?s=7545:7589#L275">Benchmark</a></h3>
	<pre>func Benchmark(f func(b *B)) BenchmarkResult</pre>
	<p>
	Benchmark benchmarks a single function. Useful for creating
	custom benchmarks that do not use the "go test" command.
	</p>






	<h3 id="BenchmarkResult.NsPerOp">func (BenchmarkResult) <a href="/src/pkg/testing/benchmark.go?s=4393:4433#L171">NsPerOp</a></h3>
	<pre>func (r BenchmarkResult) NsPerOp() int64</pre>





	<h3 id="BenchmarkResult.String">func (BenchmarkResult) <a href="/src/pkg/testing/benchmark.go?s=4677:4717#L185">String</a></h3>
	<pre>func (r BenchmarkResult) String() string</pre>







	<h2 id="InternalBenchmark">type <a href="/src/pkg/testing/benchmark.go?s=555:618#L10">InternalBenchmark</a></h2>
	<pre>type InternalBenchmark struct {
	Name string
	F func(b *B)
	}</pre>
	<p>
	An internal type but exported because it is cross-package; part of the implementation
	of the "go test" command.
	</p>














	<h2 id="InternalExample">type <a href="/src/pkg/testing/example.go?s=236:312#L6">InternalExample</a></h2>
	<pre>type InternalExample struct {
	Name string
	F func()
	Output string
	}</pre>














	<h2 id="InternalTest">type <a href="/src/pkg/testing/testing.go?s=9065:9121#L241">InternalTest</a></h2>
	<pre>type InternalTest struct {
	Name string
	F func(*T)
	}</pre>
	<p>
	An internal type but exported because it is cross-package; part of the implementation
	of the "go test" command.
	</p>














	<h2 id="T">type <a href="/src/pkg/testing/testing.go?s=6070:6199#L156">T</a></h2>
	<pre>type T struct {
	<span class="comment">// contains filtered or unexported fields</span>
	}</pre>
	<p>
	T is a type passed to Test functions to manage test state and support formatted test logs.
	Logs are accumulated during execution and dumped to standard error when done.
	</p>












	<h3 id="T.Error">func (*T) <a href="/src/pkg/testing/testing.go?s=8110:8153#L209">Error</a></h3>
	<pre>func (c *T) Error(args ...interface{})</pre>
	<p>
	Error is equivalent to Log() followed by Fail().
	</p>





	<h3 id="T.Errorf">func (*T) <a href="/src/pkg/testing/testing.go?s=8253:8312#L215">Errorf</a></h3>
	<pre>func (c *T) Errorf(format string, args ...interface{})</pre>
	<p>
	Errorf is equivalent to Logf() followed by Fail().
	</p>





	<h3 id="T.Fail">func (*T) <a href="/src/pkg/testing/testing.go?s=6270:6293#L163">Fail</a></h3>
	<pre>func (c *T) Fail()</pre>
	<p>
	Fail marks the function as having failed but continues execution.
	</p>





	<h3 id="T.FailNow">func (*T) <a href="/src/pkg/testing/testing.go?s=6548:6574#L170">FailNow</a></h3>
	<pre>func (c *T) FailNow()</pre>
	<p>
	FailNow marks the function as having failed and stops its execution.
	Execution will continue at the next test or benchmark.
	</p>





	<h3 id="T.Failed">func (*T) <a href="/src/pkg/testing/testing.go?s=6366:6396#L166">Failed</a></h3>
	<pre>func (c *T) Failed() bool</pre>
	<p>
	Failed returns whether the function has failed.
	</p>





	<h3 id="T.Fatal">func (*T) <a href="/src/pkg/testing/testing.go?s=8420:8463#L221">Fatal</a></h3>
	<pre>func (c *T) Fatal(args ...interface{})</pre>
	<p>
	Fatal is equivalent to Log() followed by FailNow().
	</p>





	<h3 id="T.Fatalf">func (*T) <a href="/src/pkg/testing/testing.go?s=8569:8628#L227">Fatalf</a></h3>
	<pre>func (c *T) Fatalf(format string, args ...interface{})</pre>
	<p>
	Fatalf is equivalent to Logf() followed by FailNow().
	</p>





	<h3 id="T.Log">func (*T) <a href="/src/pkg/testing/testing.go?s=7763:7804#L202">Log</a></h3>
	<pre>func (c *T) Log(args ...interface{})</pre>
	<p>
	Log formats its arguments using default formatting, analogous to Println(),
	and records the text in the error log.
	</p>





	<h3 id="T.Logf">func (*T) <a href="/src/pkg/testing/testing.go?s=7959:8016#L206">Logf</a></h3>
	<pre>func (c *T) Logf(format string, args ...interface{})</pre>
	<p>
	Logf formats its arguments according to the format, analogous to Printf(),
	and records the text in the error log.
	</p>





	<h3 id="T.Parallel">func (*T) <a href="/src/pkg/testing/testing.go?s=8809:8831#L234">Parallel</a></h3>
	<pre>func (t *T) Parallel()</pre>
	<p>
	Parallel signals that this test is to be run in parallel with (and only with)
	other parallel tests in this CPU group.
	</p>





	</div>












	<h2 id="subdirectories">Subdirectories</h2>

	<table class="dir">
	<tr>
	<th>Name</th>
	<th>    </th>
	<th style="text-align: left; width: auto">Synopsis</th>
	</tr>

	<tr>
	<td><a href="..">..</a></td>
	</tr>



	<tr>
	<td class="name"><a href="iotest">iotest</a></td>
	<td>    </td>
	<td style="width: auto">Package iotest implements Readers and Writers useful mainly for testing.</td>
	</tr>



	<tr>
	<td class="name"><a href="quick">quick</a></td>
	<td>    </td>
	<td style="width: auto">Package quick implements utility functions to help with black box testing.</td>
	</tr>


	</table>




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