log_test.go

     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.
     4  
     5  package log
     6  
     7  // These tests are too simple.
     8  
     9  import (
    10  	"bytes"
    11  	"fmt"
    12  	"io"
    13  	"os"
    14  	"regexp"
    15  	"strings"
    16  	"testing"
    17  	"time"
    18  )
    19  
    20  const (
    21  	Rdate         = `[0-9][0-9][0-9][0-9]/[0-9][0-9]/[0-9][0-9]`
    22  	Rtime         = `[0-9][0-9]:[0-9][0-9]:[0-9][0-9]`
    23  	Rmicroseconds = `\.[0-9][0-9][0-9][0-9][0-9][0-9]`
    24  	Rline         = `(61|63):` // must update if the calls to l.Printf / l.Print below move
    25  	Rlongfile     = `.*/[A-Za-z0-9_\-]+\.go:` + Rline
    26  	Rshortfile    = `[A-Za-z0-9_\-]+\.go:` + Rline
    27  )
    28  
    29  type tester struct {
    30  	flag    int
    31  	prefix  string
    32  	pattern string // regexp that log output must match; we add ^ and expected_text$ always
    33  }
    34  
    35  var tests = []tester{
    36  	// individual pieces:
    37  	{0, "", ""},
    38  	{0, "XXX", "XXX"},
    39  	{Ldate, "", Rdate + " "},
    40  	{Ltime, "", Rtime + " "},
    41  	{Ltime | Lmsgprefix, "XXX", Rtime + " XXX"},
    42  	{Ltime | Lmicroseconds, "", Rtime + Rmicroseconds + " "},
    43  	{Lmicroseconds, "", Rtime + Rmicroseconds + " "}, // microsec implies time
    44  	{Llongfile, "", Rlongfile + " "},
    45  	{Lshortfile, "", Rshortfile + " "},
    46  	{Llongfile | Lshortfile, "", Rshortfile + " "}, // shortfile overrides longfile
    47  	// everything at once:
    48  	{Ldate | Ltime | Lmicroseconds | Llongfile, "XXX", "XXX" + Rdate + " " + Rtime + Rmicroseconds + " " + Rlongfile + " "},
    49  	{Ldate | Ltime | Lmicroseconds | Lshortfile, "XXX", "XXX" + Rdate + " " + Rtime + Rmicroseconds + " " + Rshortfile + " "},
    50  	{Ldate | Ltime | Lmicroseconds | Llongfile | Lmsgprefix, "XXX", Rdate + " " + Rtime + Rmicroseconds + " " + Rlongfile + " XXX"},
    51  	{Ldate | Ltime | Lmicroseconds | Lshortfile | Lmsgprefix, "XXX", Rdate + " " + Rtime + Rmicroseconds + " " + Rshortfile + " XXX"},
    52  }
    53  
    54  // Test using Println("hello", 23, "world") or using Printf("hello %d world", 23)
    55  func testPrint(t *testing.T, flag int, prefix string, pattern string, useFormat bool) {
    56  	buf := new(bytes.Buffer)
    57  	SetOutput(buf)
    58  	SetFlags(flag)
    59  	SetPrefix(prefix)
    60  	if useFormat {
    61  		Printf("hello %d world", 23)
    62  	} else {
    63  		Println("hello", 23, "world")
    64  	}
    65  	line := buf.String()
    66  	line = line[0 : len(line)-1]
    67  	pattern = "^" + pattern + "hello 23 world$"
    68  	matched, err := regexp.MatchString(pattern, line)
    69  	if err != nil {
    70  		t.Fatal("pattern did not compile:", err)
    71  	}
    72  	if !matched {
    73  		t.Errorf("log output should match %q is %q", pattern, line)
    74  	}
    75  	SetOutput(os.Stderr)
    76  }
    77  
    78  func TestDefault(t *testing.T) {
    79  	if got := Default(); got != std {
    80  		t.Errorf("Default [%p] should be std [%p]", got, std)
    81  	}
    82  }
    83  
    84  func TestAll(t *testing.T) {
    85  	for _, testcase := range tests {
    86  		testPrint(t, testcase.flag, testcase.prefix, testcase.pattern, false)
    87  		testPrint(t, testcase.flag, testcase.prefix, testcase.pattern, true)
    88  	}
    89  }
    90  
    91  func TestOutput(t *testing.T) {
    92  	const testString = "test"
    93  	var b bytes.Buffer
    94  	l := New(&b, "", 0)
    95  	l.Println(testString)
    96  	if expect := testString + "\n"; b.String() != expect {
    97  		t.Errorf("log output should match %q is %q", expect, b.String())
    98  	}
    99  }
   100  
   101  func TestOutputRace(t *testing.T) {
   102  	var b bytes.Buffer
   103  	l := New(&b, "", 0)
   104  	for i := 0; i < 100; i++ {
   105  		go func() {
   106  			l.SetFlags(0)
   107  		}()
   108  		l.Output(0, "")
   109  	}
   110  }
   111  
   112  func TestFlagAndPrefixSetting(t *testing.T) {
   113  	var b bytes.Buffer
   114  	l := New(&b, "Test:", LstdFlags)
   115  	f := l.Flags()
   116  	if f != LstdFlags {
   117  		t.Errorf("Flags 1: expected %x got %x", LstdFlags, f)
   118  	}
   119  	l.SetFlags(f | Lmicroseconds)
   120  	f = l.Flags()
   121  	if f != LstdFlags|Lmicroseconds {
   122  		t.Errorf("Flags 2: expected %x got %x", LstdFlags|Lmicroseconds, f)
   123  	}
   124  	p := l.Prefix()
   125  	if p != "Test:" {
   126  		t.Errorf(`Prefix: expected "Test:" got %q`, p)
   127  	}
   128  	l.SetPrefix("Reality:")
   129  	p = l.Prefix()
   130  	if p != "Reality:" {
   131  		t.Errorf(`Prefix: expected "Reality:" got %q`, p)
   132  	}
   133  	// Verify a log message looks right, with our prefix and microseconds present.
   134  	l.Print("hello")
   135  	pattern := "^Reality:" + Rdate + " " + Rtime + Rmicroseconds + " hello\n"
   136  	matched, err := regexp.Match(pattern, b.Bytes())
   137  	if err != nil {
   138  		t.Fatalf("pattern %q did not compile: %s", pattern, err)
   139  	}
   140  	if !matched {
   141  		t.Error("message did not match pattern")
   142  	}
   143  }
   144  
   145  func TestUTCFlag(t *testing.T) {
   146  	var b bytes.Buffer
   147  	l := New(&b, "Test:", LstdFlags)
   148  	l.SetFlags(Ldate | Ltime | LUTC)
   149  	// Verify a log message looks right in the right time zone. Quantize to the second only.
   150  	now := time.Now().UTC()
   151  	l.Print("hello")
   152  	want := fmt.Sprintf("Test:%d/%.2d/%.2d %.2d:%.2d:%.2d hello\n",
   153  		now.Year(), now.Month(), now.Day(), now.Hour(), now.Minute(), now.Second())
   154  	got := b.String()
   155  	if got == want {
   156  		return
   157  	}
   158  	// It's possible we crossed a second boundary between getting now and logging,
   159  	// so add a second and try again. This should very nearly always work.
   160  	now = now.Add(time.Second)
   161  	want = fmt.Sprintf("Test:%d/%.2d/%.2d %.2d:%.2d:%.2d hello\n",
   162  		now.Year(), now.Month(), now.Day(), now.Hour(), now.Minute(), now.Second())
   163  	if got == want {
   164  		return
   165  	}
   166  	t.Errorf("got %q; want %q", got, want)
   167  }
   168  
   169  func TestEmptyPrintCreatesLine(t *testing.T) {
   170  	var b bytes.Buffer
   171  	l := New(&b, "Header:", LstdFlags)
   172  	l.Print()
   173  	l.Println("non-empty")
   174  	output := b.String()
   175  	if n := strings.Count(output, "Header"); n != 2 {
   176  		t.Errorf("expected 2 headers, got %d", n)
   177  	}
   178  	if n := strings.Count(output, "\n"); n != 2 {
   179  		t.Errorf("expected 2 lines, got %d", n)
   180  	}
   181  }
   182  
   183  func TestDiscard(t *testing.T) {
   184  	l := New(io.Discard, "", 0)
   185  	s := strings.Repeat("a", 102400)
   186  	c := testing.AllocsPerRun(100, func() { l.Printf("%s", s) })
   187  	// One allocation for slice passed to Printf,
   188  	// but none for formatting of long string.
   189  	if c > 1 {
   190  		t.Errorf("got %v allocs, want at most 1", c)
   191  	}
   192  }
   193  
   194  func BenchmarkItoa(b *testing.B) {
   195  	dst := make([]byte, 0, 64)
   196  	for i := 0; i < b.N; i++ {
   197  		dst = dst[0:0]
   198  		itoa(&dst, 2015, 4)   // year
   199  		itoa(&dst, 1, 2)      // month
   200  		itoa(&dst, 30, 2)     // day
   201  		itoa(&dst, 12, 2)     // hour
   202  		itoa(&dst, 56, 2)     // minute
   203  		itoa(&dst, 0, 2)      // second
   204  		itoa(&dst, 987654, 6) // microsecond
   205  	}
   206  }
   207  
   208  func BenchmarkPrintln(b *testing.B) {
   209  	const testString = "test"
   210  	var buf bytes.Buffer
   211  	l := New(&buf, "", LstdFlags)
   212  	for i := 0; i < b.N; i++ {
   213  		buf.Reset()
   214  		l.Println(testString)
   215  	}
   216  }
   217  
   218  func BenchmarkPrintlnNoFlags(b *testing.B) {
   219  	const testString = "test"
   220  	var buf bytes.Buffer
   221  	l := New(&buf, "", 0)
   222  	for i := 0; i < b.N; i++ {
   223  		buf.Reset()
   224  		l.Println(testString)
   225  	}
   226  }
   227
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