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// 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.
// 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
// where Xxx does not start with a lowercase letter. The function name
// serves to identify the test routine.
// Within these functions, use the Error, Fail or related methods to signal failure.
//
// To write a new test suite, create a file that
// contains the TestXxx functions as described here,
// and give that file a name ending in "_test.go".
// The file will be excluded from regular
// package builds but will be included when the "go test" command is run.
// The test file can be in the same package as the one being tested,
// or in a corresponding package with the suffix "_test".
//
// If the test file is in the same package, it may refer to unexported
// identifiers within the package, as in this example:
//
// package abs
//
// import "testing"
// func TestAbs(t *testing.T) {
// got := Abs(-1)
// if got != 1 {
// t.Errorf("Abs(-1) = %d; want 1", got)
// }
// }
// If the file is in a separate "_test" package, the package being tested
// must be imported explicitly and only its exported identifiers may be used.
// This is known as "black box" testing.
//
// package abs_test
//
// import (
// "testing"
//
// "path_to_pkg/abs"
// )
//
// func TestAbs(t *testing.T) {
// got := abs.Abs(-1)
// if got != 1 {
// t.Errorf("Abs(-1) = %d; want 1", got)
// }
// }
//
// For more detail, run "go help test" and "go help testflag".
//
// are considered benchmarks, and are executed by the "go test" command when
// its -bench flag is provided. Benchmarks are run sequentially.
// For a description of the testing flags, see
// https://golang.org/cmd/go/#hdr-Testing_flags.
//
// A sample benchmark function looks like this:
// The benchmark function must run the target code b.N times.
// It is called multiple times with b.N adjusted until the
// benchmark function lasts long enough to be timed reliably.
// The output
// means that the loop ran 68453040 times at a speed of 17.8 ns per loop.
//
// If a benchmark needs some expensive setup before running, the timer
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// may be reset:
// func BenchmarkBigLen(b *testing.B) {
// big := NewBig()
// b.ResetTimer()
// If a benchmark needs to test performance in a parallel setting, it may use
// the RunParallel helper function; such benchmarks are intended to be used with
// the go test -cpu flag:
//
// func BenchmarkTemplateParallel(b *testing.B) {
// templ := template.Must(template.New("test").Parse("Hello, {{.}}!"))
// b.RunParallel(func(pb *testing.PB) {
// var buf bytes.Buffer
// for pb.Next() {
// buf.Reset()
// templ.Execute(&buf, "World")
// }
// })
// }
// A detailed specification of the benchmark results format is given
// in https://golang.org/design/14313-benchmark-format.
//
// There are standard tools for working with benchmark results at
// https://golang.org/x/perf/cmd.
// In particular, https://golang.org/x/perf/cmd/benchstat performs
// statistically robust A/B comparisons.
//
// The package also runs and verifies example code. Example functions may
// include a concluding line comment that begins with "Output:" and is compared with
// the standard output of the function when the tests are run. (The comparison
// ignores leading and trailing space.) These are examples of an example:
// func ExampleHello() {
// fmt.Println("hello")
// // Output: hello
// }
// func ExampleSalutations() {
// fmt.Println("hello, and")
// fmt.Println("goodbye")
// // Output:
// // hello, and
// // goodbye
// }
//
// The comment prefix "Unordered output:" is like "Output:", but matches any
// line order:
//
// func ExamplePerm() {
// for _, value := range Perm(5) {
// fmt.Println(value)
// }
// // Unordered output: 4
// // 2
// // 1
// // 3
// // 0
// }
//
// Example functions without output comments are compiled but not executed.
// The naming convention to declare examples for the package, a function F, a type T and
// func Example() { ... }
// func ExampleF() { ... }
// func ExampleT() { ... }
// func ExampleT_M() { ... }
// Multiple example functions for a package/type/function/method may be provided by
// appending a distinct suffix to the name. The suffix must start with a
// lower-case letter.
//
// func Example_suffix() { ... }
// func ExampleF_suffix() { ... }
// func ExampleT_suffix() { ... }
// func ExampleT_M_suffix() { ... }
// 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.
//
// 'go test' and the testing package support fuzzing, a testing technique where
// a function is called with randomly generated inputs to find bugs not
// anticipated by unit tests.
//
//
// func FuzzHex(f *testing.F) {
// for _, seed := range [][]byte{{}, {0}, {9}, {0xa}, {0xf}, {1, 2, 3, 4}} {
// f.Add(seed)
// }
// f.Fuzz(func(t *testing.T, in []byte) {
// enc := hex.EncodeToString(in)
// out, err := hex.DecodeString(enc)
// if err != nil {
// t.Fatalf("%v: decode: %v", in, err)
// }
// if !bytes.Equal(in, out) {
// t.Fatalf("%v: not equal after round trip: %v", in, out)
// }
// })
// }
// A fuzz test maintains a seed corpus, or a set of inputs which are run by
// default, and can seed input generation. Seed inputs may be registered by
// calling (*F).Add or by storing files in the directory testdata/fuzz/<Name>
// (where <Name> is the name of the fuzz test) within the package containing
// the fuzz test. Seed inputs are optional, but the fuzzing engine may find
// bugs more efficiently when provided with a set of small seed inputs with good
// code coverage. These seed inputs can also serve as regression tests for bugs
// identified through fuzzing.
//
// The function passed to (*F).Fuzz within the fuzz test is considered the fuzz
// target. A fuzz target must accept a *T parameter, followed by one or more
// parameters for random inputs. The types of arguments passed to (*F).Add must
// be identical to the types of these parameters. The fuzz target may signal
// that it's found a problem the same way tests do: by calling T.Fail (or any
// method that calls it like T.Error or T.Fatal) or by panicking.
//
// When fuzzing is enabled (by setting the -fuzz flag to a regular expression
// that matches a specific fuzz test), the fuzz target is called with arguments
// generated by repeatedly making random changes to the seed inputs. On
// supported platforms, 'go test' compiles the test executable with fuzzing
// coverage instrumentation. The fuzzing engine uses that instrumentation to
// find and cache inputs that expand coverage, increasing the likelihood of
// finding bugs. If the fuzz target fails for a given input, the fuzzing engine
// writes the inputs that caused the failure to a file in the directory
// testdata/fuzz/<Name> within the package directory. This file later serves as
// a seed input. If the file can't be written at that location (for example,
// because the directory is read-only), the fuzzing engine writes the file to
// the fuzz cache directory within the build cache instead.
//
// When fuzzing is disabled, the fuzz target is called with the seed inputs
// registered with F.Add and seed inputs from testdata/fuzz/<Name>. In this
// mode, the fuzz test acts much like a regular test, with subtests started
//
// See https://go.dev/doc/fuzz for documentation about fuzzing.
//
//
// Tests or benchmarks may be skipped at run time with a call to
// the Skip method of *T or *B:
//
// func TestTimeConsuming(t *testing.T) {
// if testing.Short() {
// t.Skip("skipping test in short mode.")
// }
// ...
// }
// The Skip method of *T can be used in a fuzz target if the input is invalid,
// but should not be considered a failing input. For example:
//
// func FuzzJSONMarshaling(f *testing.F) {
// f.Fuzz(func(t *testing.T, b []byte) {
// var v interface{}
// if err := json.Unmarshal(b, &v); err != nil {
// t.Skip()
// }
// if _, err := json.Marshal(v); err != nil {
// t.Errorf("Marshal: %v", err)
//
//
// The Run methods of T and B allow defining subtests and sub-benchmarks,
// without having to define separate functions for each. This enables uses
// like table-driven benchmarks and creating hierarchical tests.
// It also provides a way to share common setup and tear-down code:
//
// func TestFoo(t *testing.T) {
// // <setup code>
// t.Run("A=1", func(t *testing.T) { ... })
// t.Run("A=2", func(t *testing.T) { ... })
// t.Run("B=1", func(t *testing.T) { ... })
// // <tear-down code>
// }
//
// Each subtest and sub-benchmark has a unique name: the combination of the name
// of the top-level test and the sequence of names passed to Run, separated by
// slashes, with an optional trailing sequence number for disambiguation.
//
// The argument to the -run, -bench, and -fuzz command-line flags is an unanchored regular
// expression that matches the test's name. For tests with multiple slash-separated
// elements, such as subtests, the argument is itself slash-separated, with
// expressions matching each name element in turn. Because it is unanchored, an
// empty expression matches any string.
// For example, using "matching" to mean "whose name contains":
//
// go test -run '' # Run all tests.
// go test -run Foo # Run top-level tests matching "Foo", such as "TestFooBar".
// go test -run Foo/A= # For top-level tests matching "Foo", run subtests matching "A=".
// go test -run /A=1 # For all top-level tests, run subtests matching "A=1".
// go test -fuzz FuzzFoo # Fuzz the target matching "FuzzFoo"
//
// The -run argument can also be used to run a specific value in the seed
// corpus, for debugging. For example:
//
// The -fuzz and -run flags can both be set, in order to fuzz a target but
// skip the execution of all other tests.
//
// Subtests can also be used to control parallelism. A parent test will only
// complete once all of its subtests complete. In this example, all tests are
// run in parallel with each other, and only with each other, regardless of
// other top-level tests that may be defined:
//
// func TestGroupedParallel(t *testing.T) {
// for _, tc := range tests {
// tc := tc // capture range variable
// t.Run(tc.Name, func(t *testing.T) {
// t.Parallel()
// ...
// })
// }
// }
//
// Run does not return until parallel subtests have completed, providing a way
// to clean up after a group of parallel tests:
//
// func TestTeardownParallel(t *testing.T) {
// // This Run will not return until the parallel tests finish.
// t.Run("group", func(t *testing.T) {
// t.Run("Test1", parallelTest1)
// t.Run("Test2", parallelTest2)
// t.Run("Test3", parallelTest3)
// })
// // <tear-down code>
// }
//
// # Main
// It is sometimes necessary for a test or benchmark program to do extra setup or teardown
// before or after it executes. It is also sometimes necessary to control
// which code runs on the main thread. To support these and other cases,
// if a test file contains a function:
//
// func TestMain(m *testing.M)
//
// then the generated test will call TestMain(m) instead of running the tests or benchmarks
// directly. TestMain runs in the main goroutine and can do whatever setup
// and teardown is necessary around a call to m.Run. m.Run will return an exit
// code that may be passed to os.Exit. If TestMain returns, the test wrapper
// will pass the result of m.Run to os.Exit itself.
//
// When TestMain is called, flag.Parse has not been run. If TestMain depends on
// command-line flags, including those of the testing package, it should call
// flag.Parse explicitly. Command line flags are always parsed by the time test
// or benchmark functions run.
// A simple implementation of TestMain is:
// func TestMain(m *testing.M) {
// // call flag.Parse() here if TestMain uses flags
// TestMain is a low-level primitive and should not be necessary for casual
// testing needs, where ordinary test functions suffice.
"errors"
"internal/goexperiment"
"internal/race"
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"math/rand"
"runtime/debug"
"slices"
"strings"
"unicode"
"unicode/utf8"
var initRan bool
// Init registers testing flags. These flags are automatically registered by
// the "go test" command before running test functions, so Init is only needed
// when calling functions such as Benchmark without using "go test".
//
// Init is not safe to call concurrently. It has no effect if it was already called.
func Init() {
if initRan {
return
}
initRan = true
// The short flag requests that tests run more quickly, but its functionality
// is provided by test writers themselves. The testing package is just its
// home. The all.bash installation script sets it to make installation more
// efficient, but by default the flag is off so a plain "go test" will do a
// full test of the package.
short = flag.Bool("test.short", false, "run smaller test suite to save time")
// The failfast flag requests that test execution stop after the first test failure.
failFast = flag.Bool("test.failfast", false, "do not start new tests after the first test failure")
// The directory in which to create profile files and the like. When run from
// "go test", the binary always runs in the source directory for the package;
// this flag lets "go test" tell the binary to write the files in the directory where
// the "go test" command is run.
outputDir = flag.String("test.outputdir", "", "write profiles to `dir`")
// Report as tests are run; default is silent for success.
flag.Var(&chatty, "test.v", "verbose: print additional output")
count = flag.Uint("test.count", 1, "run tests and benchmarks `n` times")
coverProfile = flag.String("test.coverprofile", "", "write a coverage profile to `file`")
gocoverdir = flag.String("test.gocoverdir", "", "write coverage intermediate files to this directory")
matchList = flag.String("test.list", "", "list tests, examples, and benchmarks matching `regexp` then exit")
match = flag.String("test.run", "", "run only tests and examples matching `regexp`")
skip = flag.String("test.skip", "", "do not list or run tests matching `regexp`")
memProfile = flag.String("test.memprofile", "", "write an allocation profile to `file`")
memProfileRate = flag.Int("test.memprofilerate", 0, "set memory allocation profiling `rate` (see runtime.MemProfileRate)")
cpuProfile = flag.String("test.cpuprofile", "", "write a cpu profile to `file`")
blockProfile = flag.String("test.blockprofile", "", "write a goroutine blocking profile to `file`")
blockProfileRate = flag.Int("test.blockprofilerate", 1, "set blocking profile `rate` (see runtime.SetBlockProfileRate)")
mutexProfile = flag.String("test.mutexprofile", "", "write a mutex contention profile to the named file after execution")
mutexProfileFraction = flag.Int("test.mutexprofilefraction", 1, "if >= 0, calls runtime.SetMutexProfileFraction()")
panicOnExit0 = flag.Bool("test.paniconexit0", false, "panic on call to os.Exit(0)")
traceFile = flag.String("test.trace", "", "write an execution trace to `file`")
timeout = flag.Duration("test.timeout", 0, "panic test binary after duration `d` (default 0, timeout disabled)")
cpuListStr = flag.String("test.cpu", "", "comma-separated `list` of cpu counts to run each test with")
parallel = flag.Int("test.parallel", runtime.GOMAXPROCS(0), "run at most `n` tests in parallel")
testlog = flag.String("test.testlogfile", "", "write test action log to `file` (for use only by cmd/go)")
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shuffle = flag.String("test.shuffle", "off", "randomize the execution order of tests and benchmarks")
fullPath = flag.Bool("test.fullpath", false, "show full file names in error messages")
initBenchmarkFlags()
initFuzzFlags()
}
var (
// Flags, registered during Init.
short *bool
failFast *bool
outputDir *string
count *uint
coverProfile *string
matchList *string
match *string
memProfile *string
memProfileRate *int
cpuProfile *string
blockProfile *string
blockProfileRate *int
mutexProfile *string
mutexProfileFraction *int
panicOnExit0 *bool
traceFile *string
timeout *time.Duration
cpuListStr *string
parallel *int
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shuffle *string
testlog *string
haveExamples bool // are there examples?
cpuList []int
testlogFile *os.File
numFailed atomic.Uint32 // number of test failures
running sync.Map // map[string]time.Time of running, unpaused tests
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type chattyFlag struct {
on bool // -v is set in some form
json bool // -v=test2json is set, to make output better for test2json
}
func (*chattyFlag) IsBoolFlag() bool { return true }
func (f *chattyFlag) Set(arg string) error {
switch arg {
default:
return fmt.Errorf("invalid flag -test.v=%s", arg)
case "true", "test2json":
f.on = true
f.json = arg == "test2json"
case "false":
f.on = false
f.json = false
}
return nil
}
func (f *chattyFlag) String() string {
if f.json {
return "test2json"
}
if f.on {
return "true"
}
return "false"
}
func (f *chattyFlag) Get() any {
if f.json {
return "test2json"
}
return f.on
}
const marker = byte(0x16) // ^V for framing
func (f *chattyFlag) prefix() string {
if f.json {
return string(marker)
}
return ""
}
type chattyPrinter struct {
w io.Writer
lastNameMu sync.Mutex // guards lastName
lastName string // last printed test name in chatty mode
func newChattyPrinter(w io.Writer) *chattyPrinter {
return &chattyPrinter{w: w, json: chatty.json}
}
// prefix is like chatty.prefix but using p.json instead of chatty.json.
// Using p.json allows tests to check the json behavior without modifying
// the global variable. For convenience, we allow p == nil and treat
// that as not in json mode (because it's not chatty at all).
func (p *chattyPrinter) prefix() string {
if p != nil && p.json {
return string(marker)
}
return ""
// Updatef prints a message about the status of the named test to w.
//
// The formatted message must include the test name itself.
func (p *chattyPrinter) Updatef(testName, format string, args ...any) {
p.lastNameMu.Lock()
defer p.lastNameMu.Unlock()
// Since the message already implies an association with a specific new test,
// we don't need to check what the old test name was or log an extra NAME line
// for it. (We're updating it anyway, and the current message already includes
// the test name.)
p.lastName = testName
fmt.Fprintf(p.w, p.prefix()+format, args...)
// Printf prints a message, generated by the named test, that does not
// necessarily mention that tests's name itself.
func (p *chattyPrinter) Printf(testName, format string, args ...any) {
p.lastNameMu.Lock()
defer p.lastNameMu.Unlock()
if p.lastName == "" {
p.lastName = testName
} else if p.lastName != testName {
fmt.Fprintf(p.w, "%s=== NAME %s\n", p.prefix(), testName)
fmt.Fprintf(p.w, format, args...)
// The maximum number of stack frames to go through when skipping helper functions for
// the purpose of decorating log messages.
const maxStackLen = 50
// common holds the elements common between T and B and
// captures common methods such as Errorf.
type common struct {
mu sync.RWMutex // guards this group of fields
output []byte // Output generated by test or benchmark.
w io.Writer // For flushToParent.
ran bool // Test or benchmark (or one of its subtests) was executed.
failed bool // Test or benchmark has failed.
skipped bool // Test or benchmark has been skipped.
done bool // Test is finished and all subtests have completed.
helperPCs map[uintptr]struct{} // functions to be skipped when writing file/line info
helperNames map[string]struct{} // helperPCs converted to function names
cleanups []func() // optional functions to be called at the end of the test
cleanupName string // Name of the cleanup function.
cleanupPc []uintptr // The stack trace at the point where Cleanup was called.
finished bool // Test function has completed.
inFuzzFn bool // Whether the fuzz target, if this is one, is running.
chatty *chattyPrinter // A copy of chattyPrinter, if the chatty flag is set.
bench bool // Whether the current test is a benchmark.
hasSub atomic.Bool // whether there are sub-benchmarks.
cleanupStarted atomic.Bool // Registered cleanup callbacks have started to execute
runner string // Function name of tRunner running the test.
isParallel bool // Whether the test is parallel.
parent *common
level int // Nesting depth of test or benchmark.
creator []uintptr // If level > 0, the stack trace at the point where the parent called t.Run.
name string // Name of test or benchmark.
start highPrecisionTime // Time test or benchmark started
duration time.Duration
barrier chan bool // To signal parallel subtests they may start. Nil when T.Parallel is not present (B) or not usable (when fuzzing).
signal chan bool // To signal a test is done.
sub []*T // Queue of subtests to be run in parallel.
lastRaceErrors atomic.Int64 // Max value of race.Errors seen during the test or its subtests.
raceErrorLogged atomic.Bool
tempDirMu sync.Mutex
tempDir string
tempDirErr error
tempDirSeq int32
// Short reports whether the -test.short flag is set.
func Short() bool {
if short == nil {
panic("testing: Short called before Init")
}
// Catch code that calls this from TestMain without first calling flag.Parse.
if !flag.Parsed() {
panic("testing: Short called before Parse")
}
return *short
}
// testBinary is set by cmd/go to "1" if this is a binary built by "go test".
// The value is set to "1" by a -X option to cmd/link. We assume that
// because this is possible, the compiler will not optimize testBinary
// into a constant on the basis that it is an unexported package-scope
// variable that is never changed. If the compiler ever starts implementing
// such an optimization, we will need some technique to mark this variable
// as "changed by a cmd/link -X option".
var testBinary = "0"
// Testing reports whether the current code is being run in a test.
// This will report true in programs created by "go test",
// false in programs created by "go build".
func Testing() bool {
return testBinary == "1"
}
// CoverMode reports what the test coverage mode is set to. The
// values are "set", "count", or "atomic". The return value will be
// empty if test coverage is not enabled.
func CoverMode() string {
if goexperiment.CoverageRedesign {
return cover2.mode
}
// Verbose reports whether the -test.v flag is set.
func Verbose() bool {
if !flag.Parsed() {
panic("testing: Verbose called before Parse")
func (c *common) checkFuzzFn(name string) {
if c.inFuzzFn {
panic(fmt.Sprintf("testing: f.%s was called inside the fuzz target, use t.%s instead", name, name))
// frameSkip searches, starting after skip frames, for the first caller frame
// in a function not marked as a helper and returns that frame.
// The search stops if it finds a tRunner function that
// was the entry point into the test and the test is not a subtest.
// This function must be called with c.mu held.
func (c *common) frameSkip(skip int) runtime.Frame {
// If the search continues into the parent test, we'll have to hold
// its mu temporarily. If we then return, we need to unlock it.
shouldUnlock := false
defer func() {
if shouldUnlock {
c.mu.Unlock()
}
}()
var pc [maxStackLen]uintptr
// Skip two extra frames to account for this function
// and runtime.Callers itself.
n := runtime.Callers(skip+2, pc[:])
if n == 0 {
panic("testing: zero callers found")
}
frames := runtime.CallersFrames(pc[:n])
var firstFrame, prevFrame, frame runtime.Frame
for more := true; more; prevFrame = frame {
frame, more = frames.Next()
if frame.Function == "runtime.gopanic" {
continue
}
if frame.Function == c.cleanupName {
frames = runtime.CallersFrames(c.cleanupPc)
continue
}
if firstFrame.PC == 0 {
firstFrame = frame
}
if frame.Function == c.runner {
// We've gone up all the way to the tRunner calling
// the test function (so the user must have
// called tb.Helper from inside that test function).
// If this is a top-level test, only skip up to the test function itself.
// If we're in a subtest, continue searching in the parent test,
// starting from the point of the call to Run which created this subtest.
if c.level > 1 {
frames = runtime.CallersFrames(c.creator)
parent := c.parent
// We're no longer looking at the current c after this point,
// so we should unlock its mu, unless it's the original receiver,
// in which case our caller doesn't expect us to do that.
if shouldUnlock {
c.mu.Unlock()
}
c = parent
// Remember to unlock c.mu when we no longer need it, either
// because we went up another nesting level, or because we
// returned.
shouldUnlock = true
c.mu.Lock()
continue
}
return prevFrame
// If more helper PCs have been added since we last did the conversion
if c.helperNames == nil {
c.helperNames = make(map[string]struct{})
for pc := range c.helperPCs {
c.helperNames[pcToName(pc)] = struct{}{}
}
}
if _, ok := c.helperNames[frame.Function]; !ok {
// Found a frame that wasn't inside a helper function.
return frame
return firstFrame
// decorate prefixes the string with the file and line of the call site
// and inserts the final newline if needed and indentation spaces for formatting.
// This function must be called with c.mu held.
func (c *common) decorate(s string, skip int) string {
frame := c.frameSkip(skip)
file := frame.File
line := frame.Line
if file != "" {
if *fullPath {
// If relative path, truncate file name at last file name separator.
} else if index := strings.LastIndexAny(file, `/\`); index >= 0 {
file = file[index+1:]
} else {
file = "???"
}
if line == 0 {
buf := new(strings.Builder)
// Every line is indented at least 4 spaces.
buf.WriteString(" ")
fmt.Fprintf(buf, "%s:%d: ", file, line)
lines := strings.Split(s, "\n")
if l := len(lines); l > 1 && lines[l-1] == "" {
lines = lines[:l-1]
}
for i, line := range lines {
if i > 0 {
// Second and subsequent lines are indented an additional 4 spaces.
buf.WriteString("\n ")
buf.WriteString(line)
}
return buf.String()
// flushToParent writes c.output to the parent after first writing the header
// with the given format and arguments.
func (c *common) flushToParent(testName, format string, args ...any) {
p := c.parent
p.mu.Lock()
defer p.mu.Unlock()
c.mu.Lock()
defer c.mu.Unlock()
if len(c.output) > 0 {
// Add the current c.output to the print,
// and then arrange for the print to replace c.output.
// (This displays the logged output after the --- FAIL line.)
format += "%s"
args = append(args[:len(args):len(args)], c.output)
}
if c.chatty != nil && (p.w == c.chatty.w || c.chatty.json) {
// We're flushing to the actual output, so track that this output is
// associated with a specific test (and, specifically, that the next output
// is *not* associated with that test).
//
// Moreover, if c.output is non-empty it is important that this write be
// atomic with respect to the output of other tests, so that we don't end up
// with confusing '=== NAME' lines in the middle of our '--- PASS' block.
// Neither humans nor cmd/test2json can parse those easily.
// (See https://go.dev/issue/40771.)
//
// If test2json is used, we never flush to parent tests,
// so that the json stream shows subtests as they finish.
// (See https://go.dev/issue/29811.)
c.chatty.Updatef(testName, format, args...)
} else {
// We're flushing to the output buffer of the parent test, which will
// itself follow a test-name header when it is finally flushed to stdout.
fmt.Fprintf(p.w, c.chatty.prefix()+format, args...)
}
type indenter struct {
c *common
}
func (w indenter) Write(b []byte) (n int, err error) {
n = len(b)
for len(b) > 0 {
end := bytes.IndexByte(b, '\n')
if end == -1 {
end = len(b)
} else {
end++
}
// An indent of 4 spaces will neatly align the dashes with the status
// indicator of the parent.
line := b[:end]
if line[0] == marker {
w.c.output = append(w.c.output, marker)
line = line[1:]
}
const indent = " "
w.c.output = append(w.c.output, indent...)
w.c.output = append(w.c.output, line...)
b = b[end:]
}
return
}
// fmtDuration returns a string representing d in the form "87.00s".
func fmtDuration(d time.Duration) string {
return fmt.Sprintf("%.2fs", d.Seconds())
}
// TB is the interface common to T, B, and F.
Error(args ...any)
Errorf(format string, args ...any)
Fail()
FailNow()
Failed() bool
Fatal(args ...any)
Fatalf(format string, args ...any)
Log(args ...any)
Logf(format string, args ...any)
// A private method to prevent users implementing the
// interface and so future additions to it will not
// violate Go 1 compatibility.
private()
}
var _ TB = (*T)(nil)
var _ TB = (*B)(nil)
// T is a type passed to Test functions to manage test state and support formatted test logs.
//
// A test ends when its Test function returns or calls any of the methods
// FailNow, Fatal, Fatalf, SkipNow, Skip, or Skipf. Those methods, as well as
// the Parallel method, must be called only from the goroutine running the
// Test function.
//
// The other reporting methods, such as the variations of Log and Error,
// may be called simultaneously from multiple goroutines.
denyParallel bool
context *testContext // For running tests and subtests.
func (c *common) private() {}
// Name returns the name of the running (sub-) test or benchmark.
//
// The name will include the name of the test along with the names of
// any nested sub-tests. If two sibling sub-tests have the same name,
// Name will append a suffix to guarantee the returned name is unique.
func (c *common) Name() string {
return c.name
}
func (c *common) setRan() {
if c.parent != nil {
c.parent.setRan()
}
c.mu.Lock()
defer c.mu.Unlock()
// Fail marks the function as having failed but continues execution.
if c.parent != nil {
c.parent.Fail()
}
c.mu.Lock()
defer c.mu.Unlock()
Marcel van Lohuizen
committed
// c.done needs to be locked to synchronize checks to c.done in parent tests.
if c.done {
panic("Fail in goroutine after " + c.name + " has completed")
}
// Failed reports whether the function has failed.
func (c *common) Failed() bool {
defer c.mu.RUnlock()
if !c.done && int64(race.Errors()) > c.lastRaceErrors.Load() {
c.mu.RUnlock()
c.checkRaces()
c.mu.RLock()
}
return c.failed
// FailNow marks the function as having failed and stops its execution
// by calling runtime.Goexit (which then runs all deferred calls in the
// current goroutine).
// Execution will continue at the next test or benchmark.
// FailNow must be called from the goroutine running the
// test or benchmark function, not from other goroutines
// created during the test. Calling FailNow does not stop
// those other goroutines.
c.checkFuzzFn("FailNow")
// Calling runtime.Goexit will exit the goroutine, which
// will run the deferred functions in this goroutine,
// which will eventually run the deferred lines in tRunner,
// which will signal to the test loop that this test is done.
//
// A previous version of this code said:
//
// c.duration = ...
// c.signal <- c.self
// runtime.Goexit()
//
// This previous version duplicated code (those lines are in
// tRunner no matter what), but worse the goroutine teardown
// implicit in runtime.Goexit was not guaranteed to complete
// before the test exited. If a test deferred an important cleanup