github.com/geraldss/go/src@v0.0.0-20210511222824-ac7d0ebfc235/testing/internal/testdeps/deps.go (about)

     1  // Copyright 2016 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  // Package testdeps provides access to dependencies needed by test execution.
     6  //
     7  // This package is imported by the generated main package, which passes
     8  // TestDeps into testing.Main. This allows tests to use packages at run time
     9  // without making those packages direct dependencies of package testing.
    10  // Direct dependencies of package testing are harder to write tests for.
    11  package testdeps
    12  
    13  import (
    14  	"bufio"
    15  	"internal/testlog"
    16  	"io"
    17  	"regexp"
    18  	"runtime/pprof"
    19  	"strings"
    20  	"sync"
    21  )
    22  
    23  // TestDeps is an implementation of the testing.testDeps interface,
    24  // suitable for passing to testing.MainStart.
    25  type TestDeps struct{}
    26  
    27  var matchPat string
    28  var matchRe *regexp.Regexp
    29  
    30  func (TestDeps) MatchString(pat, str string) (result bool, err error) {
    31  	if matchRe == nil || matchPat != pat {
    32  		matchPat = pat
    33  		matchRe, err = regexp.Compile(matchPat)
    34  		if err != nil {
    35  			return
    36  		}
    37  	}
    38  	return matchRe.MatchString(str), nil
    39  }
    40  
    41  func (TestDeps) StartCPUProfile(w io.Writer) error {
    42  	return pprof.StartCPUProfile(w)
    43  }
    44  
    45  func (TestDeps) StopCPUProfile() {
    46  	pprof.StopCPUProfile()
    47  }
    48  
    49  func (TestDeps) WriteProfileTo(name string, w io.Writer, debug int) error {
    50  	return pprof.Lookup(name).WriteTo(w, debug)
    51  }
    52  
    53  // ImportPath is the import path of the testing binary, set by the generated main function.
    54  var ImportPath string
    55  
    56  func (TestDeps) ImportPath() string {
    57  	return ImportPath
    58  }
    59  
    60  // testLog implements testlog.Interface, logging actions by package os.
    61  type testLog struct {
    62  	mu  sync.Mutex
    63  	w   *bufio.Writer
    64  	set bool
    65  }
    66  
    67  func (l *testLog) Getenv(key string) {
    68  	l.add("getenv", key)
    69  }
    70  
    71  func (l *testLog) Open(name string) {
    72  	l.add("open", name)
    73  }
    74  
    75  func (l *testLog) Stat(name string) {
    76  	l.add("stat", name)
    77  }
    78  
    79  func (l *testLog) Chdir(name string) {
    80  	l.add("chdir", name)
    81  }
    82  
    83  // add adds the (op, name) pair to the test log.
    84  func (l *testLog) add(op, name string) {
    85  	if strings.Contains(name, "\n") || name == "" {
    86  		return
    87  	}
    88  
    89  	l.mu.Lock()
    90  	defer l.mu.Unlock()
    91  	if l.w == nil {
    92  		return
    93  	}
    94  	l.w.WriteString(op)
    95  	l.w.WriteByte(' ')
    96  	l.w.WriteString(name)
    97  	l.w.WriteByte('\n')
    98  }
    99  
   100  var log testLog
   101  
   102  func (TestDeps) StartTestLog(w io.Writer) {
   103  	log.mu.Lock()
   104  	log.w = bufio.NewWriter(w)
   105  	if !log.set {
   106  		// Tests that define TestMain and then run m.Run multiple times
   107  		// will call StartTestLog/StopTestLog multiple times.
   108  		// Checking log.set avoids calling testlog.SetLogger multiple times
   109  		// (which will panic) and also avoids writing the header multiple times.
   110  		log.set = true
   111  		testlog.SetLogger(&log)
   112  		log.w.WriteString("# test log\n") // known to cmd/go/internal/test/test.go
   113  	}
   114  	log.mu.Unlock()
   115  }
   116  
   117  func (TestDeps) StopTestLog() error {
   118  	log.mu.Lock()
   119  	defer log.mu.Unlock()
   120  	err := log.w.Flush()
   121  	log.w = nil
   122  	return err
   123  }
   124  
   125  // SetPanicOnExit0 tells the os package whether to panic on os.Exit(0).
   126  func (TestDeps) SetPanicOnExit0(v bool) {
   127  	testlog.SetPanicOnExit0(v)
   128  }