record_test.go

     1  // Copyright 2022 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 slog
     6  
     7  import (
     8  	"slices"
     9  	"strconv"
    10  	"strings"
    11  	"testing"
    12  	"time"
    13  )
    14  
    15  func TestRecordAttrs(t *testing.T) {
    16  	as := []Attr{Int("k1", 1), String("k2", "foo"), Int("k3", 3),
    17  		Int64("k4", -1), Float64("f", 3.1), Uint64("u", 999)}
    18  	r := newRecordWithAttrs(as)
    19  	if g, w := r.NumAttrs(), len(as); g != w {
    20  		t.Errorf("NumAttrs: got %d, want %d", g, w)
    21  	}
    22  	if got := attrsSlice(r); !attrsEqual(got, as) {
    23  		t.Errorf("got %v, want %v", got, as)
    24  	}
    25  
    26  	// Early return.
    27  	// Hit both loops in Record.Attrs: front and back.
    28  	for _, stop := range []int{2, 6} {
    29  		var got []Attr
    30  		r.Attrs(func(a Attr) bool {
    31  			got = append(got, a)
    32  			return len(got) < stop
    33  		})
    34  		want := as[:stop]
    35  		if !attrsEqual(got, want) {
    36  			t.Errorf("got %v, want %v", got, want)
    37  		}
    38  	}
    39  }
    40  
    41  func TestRecordSource(t *testing.T) {
    42  	// Zero call depth => empty *Source.
    43  	for _, test := range []struct {
    44  		depth            int
    45  		wantFunction     string
    46  		wantFile         string
    47  		wantLinePositive bool
    48  	}{
    49  		{0, "", "", false},
    50  		{-16, "", "", false},
    51  		{1, "log/slog.TestRecordSource", "record_test.go", true}, // 1: caller of NewRecord
    52  		{2, "testing.tRunner", "testing.go", true},
    53  	} {
    54  		var pc uintptr
    55  		if test.depth > 0 {
    56  			pc = callerPC(test.depth + 1)
    57  		}
    58  		r := NewRecord(time.Time{}, 0, "", pc)
    59  		got := r.source()
    60  		if i := strings.LastIndexByte(got.File, '/'); i >= 0 {
    61  			got.File = got.File[i+1:]
    62  		}
    63  		if got.Function != test.wantFunction || got.File != test.wantFile || (got.Line > 0) != test.wantLinePositive {
    64  			t.Errorf("depth %d: got (%q, %q, %d), want (%q, %q, %t)",
    65  				test.depth,
    66  				got.Function, got.File, got.Line,
    67  				test.wantFunction, test.wantFile, test.wantLinePositive)
    68  		}
    69  	}
    70  }
    71  
    72  func TestAliasingAndClone(t *testing.T) {
    73  	intAttrs := func(from, to int) []Attr {
    74  		var as []Attr
    75  		for i := from; i < to; i++ {
    76  			as = append(as, Int("k", i))
    77  		}
    78  		return as
    79  	}
    80  
    81  	check := func(r Record, want []Attr) {
    82  		t.Helper()
    83  		got := attrsSlice(r)
    84  		if !attrsEqual(got, want) {
    85  			t.Errorf("got %v, want %v", got, want)
    86  		}
    87  	}
    88  
    89  	// Create a record whose Attrs overflow the inline array,
    90  	// creating a slice in r.back.
    91  	r1 := NewRecord(time.Time{}, 0, "", 0)
    92  	r1.AddAttrs(intAttrs(0, nAttrsInline+1)...)
    93  	// Ensure that r1.back's capacity exceeds its length.
    94  	b := make([]Attr, len(r1.back), len(r1.back)+1)
    95  	copy(b, r1.back)
    96  	r1.back = b
    97  	// Make a copy that shares state.
    98  	r2 := r1
    99  	// Adding to both should insert a special Attr in the second.
   100  	r1AttrsBefore := attrsSlice(r1)
   101  	r1.AddAttrs(Int("p", 0))
   102  	r2.AddAttrs(Int("p", 1))
   103  	check(r1, append(slices.Clip(r1AttrsBefore), Int("p", 0)))
   104  	r1Attrs := attrsSlice(r1)
   105  	check(r2, append(slices.Clip(r1AttrsBefore),
   106  		String("!BUG", "AddAttrs unsafely called on copy of Record made without using Record.Clone"), Int("p", 1)))
   107  
   108  	// Adding to a clone is fine.
   109  	r2 = r1.Clone()
   110  	check(r2, r1Attrs)
   111  	r2.AddAttrs(Int("p", 2))
   112  	check(r1, r1Attrs) // r1 is unchanged
   113  	check(r2, append(slices.Clip(r1Attrs), Int("p", 2)))
   114  }
   115  
   116  func newRecordWithAttrs(as []Attr) Record {
   117  	r := NewRecord(time.Now(), LevelInfo, "", 0)
   118  	r.AddAttrs(as...)
   119  	return r
   120  }
   121  
   122  func attrsSlice(r Record) []Attr {
   123  	s := make([]Attr, 0, r.NumAttrs())
   124  	r.Attrs(func(a Attr) bool { s = append(s, a); return true })
   125  	return s
   126  }
   127  
   128  func attrsEqual(as1, as2 []Attr) bool {
   129  	return slices.EqualFunc(as1, as2, Attr.Equal)
   130  }
   131  
   132  // Currently, pc(2) takes over 400ns, which is too expensive
   133  // to call it for every log message.
   134  func BenchmarkPC(b *testing.B) {
   135  	for depth := 0; depth < 5; depth++ {
   136  		b.Run(strconv.Itoa(depth), func(b *testing.B) {
   137  			b.ReportAllocs()
   138  			var x uintptr
   139  			for i := 0; i < b.N; i++ {
   140  				x = callerPC(depth)
   141  			}
   142  			_ = x
   143  		})
   144  	}
   145  }
   146  
   147  func BenchmarkRecord(b *testing.B) {
   148  	const nAttrs = nAttrsInline * 10
   149  	var a Attr
   150  
   151  	for i := 0; i < b.N; i++ {
   152  		r := NewRecord(time.Time{}, LevelInfo, "", 0)
   153  		for j := 0; j < nAttrs; j++ {
   154  			r.AddAttrs(Int("k", j))
   155  		}
   156  		r.Attrs(func(b Attr) bool { a = b; return true })
   157  	}
   158  	_ = a
   159  }
   160
View as plain text