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authorRuss Cox <rsc@golang.org>2014-09-08 00:08:51 -0400
committerRuss Cox <rsc@golang.org>2014-09-08 00:08:51 -0400
commitc007ce824d9a4fccb148f9204e04c23ed2984b71 (patch)
tree7dcac257114ef5c446be5b7b68c27dea230b7c09 /src/runtime/map_test.go
parent220a6de47eced55956eb8af8d643d4f5b67fd634 (diff)
downloadgo-c007ce824d9a4fccb148f9204e04c23ed2984b71.tar.gz
go-c007ce824d9a4fccb148f9204e04c23ed2984b71.zip
build: move package sources from src/pkg to src
Preparation was in CL 134570043. This CL contains only the effect of 'hg mv src/pkg/* src'. For more about the move, see golang.org/s/go14nopkg.
Diffstat (limited to 'src/runtime/map_test.go')
-rw-r--r--src/runtime/map_test.go477
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diff --git a/src/runtime/map_test.go b/src/runtime/map_test.go
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+// Copyright 2013 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 runtime_test
+
+import (
+ "fmt"
+ "math"
+ "reflect"
+ "runtime"
+ "sort"
+ "strings"
+ "sync"
+ "testing"
+)
+
+// negative zero is a good test because:
+// 1) 0 and -0 are equal, yet have distinct representations.
+// 2) 0 is represented as all zeros, -0 isn't.
+// I'm not sure the language spec actually requires this behavior,
+// but it's what the current map implementation does.
+func TestNegativeZero(t *testing.T) {
+ m := make(map[float64]bool, 0)
+
+ m[+0.0] = true
+ m[math.Copysign(0.0, -1.0)] = true // should overwrite +0 entry
+
+ if len(m) != 1 {
+ t.Error("length wrong")
+ }
+
+ for k := range m {
+ if math.Copysign(1.0, k) > 0 {
+ t.Error("wrong sign")
+ }
+ }
+
+ m = make(map[float64]bool, 0)
+ m[math.Copysign(0.0, -1.0)] = true
+ m[+0.0] = true // should overwrite -0.0 entry
+
+ if len(m) != 1 {
+ t.Error("length wrong")
+ }
+
+ for k := range m {
+ if math.Copysign(1.0, k) < 0 {
+ t.Error("wrong sign")
+ }
+ }
+}
+
+// nan is a good test because nan != nan, and nan has
+// a randomized hash value.
+func TestNan(t *testing.T) {
+ m := make(map[float64]int, 0)
+ nan := math.NaN()
+ m[nan] = 1
+ m[nan] = 2
+ m[nan] = 4
+ if len(m) != 3 {
+ t.Error("length wrong")
+ }
+ s := 0
+ for k, v := range m {
+ if k == k {
+ t.Error("nan disappeared")
+ }
+ if (v & (v - 1)) != 0 {
+ t.Error("value wrong")
+ }
+ s |= v
+ }
+ if s != 7 {
+ t.Error("values wrong")
+ }
+}
+
+// Maps aren't actually copied on assignment.
+func TestAlias(t *testing.T) {
+ m := make(map[int]int, 0)
+ m[0] = 5
+ n := m
+ n[0] = 6
+ if m[0] != 6 {
+ t.Error("alias didn't work")
+ }
+}
+
+func TestGrowWithNaN(t *testing.T) {
+ m := make(map[float64]int, 4)
+ nan := math.NaN()
+ m[nan] = 1
+ m[nan] = 2
+ m[nan] = 4
+ cnt := 0
+ s := 0
+ growflag := true
+ for k, v := range m {
+ if growflag {
+ // force a hashtable resize
+ for i := 0; i < 100; i++ {
+ m[float64(i)] = i
+ }
+ growflag = false
+ }
+ if k != k {
+ cnt++
+ s |= v
+ }
+ }
+ if cnt != 3 {
+ t.Error("NaN keys lost during grow")
+ }
+ if s != 7 {
+ t.Error("NaN values lost during grow")
+ }
+}
+
+type FloatInt struct {
+ x float64
+ y int
+}
+
+func TestGrowWithNegativeZero(t *testing.T) {
+ negzero := math.Copysign(0.0, -1.0)
+ m := make(map[FloatInt]int, 4)
+ m[FloatInt{0.0, 0}] = 1
+ m[FloatInt{0.0, 1}] = 2
+ m[FloatInt{0.0, 2}] = 4
+ m[FloatInt{0.0, 3}] = 8
+ growflag := true
+ s := 0
+ cnt := 0
+ negcnt := 0
+ // The first iteration should return the +0 key.
+ // The subsequent iterations should return the -0 key.
+ // I'm not really sure this is required by the spec,
+ // but it makes sense.
+ // TODO: are we allowed to get the first entry returned again???
+ for k, v := range m {
+ if v == 0 {
+ continue
+ } // ignore entries added to grow table
+ cnt++
+ if math.Copysign(1.0, k.x) < 0 {
+ if v&16 == 0 {
+ t.Error("key/value not updated together 1")
+ }
+ negcnt++
+ s |= v & 15
+ } else {
+ if v&16 == 16 {
+ t.Error("key/value not updated together 2", k, v)
+ }
+ s |= v
+ }
+ if growflag {
+ // force a hashtable resize
+ for i := 0; i < 100; i++ {
+ m[FloatInt{3.0, i}] = 0
+ }
+ // then change all the entries
+ // to negative zero
+ m[FloatInt{negzero, 0}] = 1 | 16
+ m[FloatInt{negzero, 1}] = 2 | 16
+ m[FloatInt{negzero, 2}] = 4 | 16
+ m[FloatInt{negzero, 3}] = 8 | 16
+ growflag = false
+ }
+ }
+ if s != 15 {
+ t.Error("entry missing", s)
+ }
+ if cnt != 4 {
+ t.Error("wrong number of entries returned by iterator", cnt)
+ }
+ if negcnt != 3 {
+ t.Error("update to negzero missed by iteration", negcnt)
+ }
+}
+
+func TestIterGrowAndDelete(t *testing.T) {
+ m := make(map[int]int, 4)
+ for i := 0; i < 100; i++ {
+ m[i] = i
+ }
+ growflag := true
+ for k := range m {
+ if growflag {
+ // grow the table
+ for i := 100; i < 1000; i++ {
+ m[i] = i
+ }
+ // delete all odd keys
+ for i := 1; i < 1000; i += 2 {
+ delete(m, i)
+ }
+ growflag = false
+ } else {
+ if k&1 == 1 {
+ t.Error("odd value returned")
+ }
+ }
+ }
+}
+
+// make sure old bucket arrays don't get GCd while
+// an iterator is still using them.
+func TestIterGrowWithGC(t *testing.T) {
+ m := make(map[int]int, 4)
+ for i := 0; i < 16; i++ {
+ m[i] = i
+ }
+ growflag := true
+ bitmask := 0
+ for k := range m {
+ if k < 16 {
+ bitmask |= 1 << uint(k)
+ }
+ if growflag {
+ // grow the table
+ for i := 100; i < 1000; i++ {
+ m[i] = i
+ }
+ // trigger a gc
+ runtime.GC()
+ growflag = false
+ }
+ }
+ if bitmask != 1<<16-1 {
+ t.Error("missing key", bitmask)
+ }
+}
+
+func testConcurrentReadsAfterGrowth(t *testing.T, useReflect bool) {
+ if runtime.GOMAXPROCS(-1) == 1 {
+ defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(16))
+ }
+ numLoop := 10
+ numGrowStep := 250
+ numReader := 16
+ if testing.Short() {
+ numLoop, numGrowStep = 2, 500
+ }
+ for i := 0; i < numLoop; i++ {
+ m := make(map[int]int, 0)
+ for gs := 0; gs < numGrowStep; gs++ {
+ m[gs] = gs
+ var wg sync.WaitGroup
+ wg.Add(numReader * 2)
+ for nr := 0; nr < numReader; nr++ {
+ go func() {
+ defer wg.Done()
+ for range m {
+ }
+ }()
+ go func() {
+ defer wg.Done()
+ for key := 0; key < gs; key++ {
+ _ = m[key]
+ }
+ }()
+ if useReflect {
+ wg.Add(1)
+ go func() {
+ defer wg.Done()
+ mv := reflect.ValueOf(m)
+ keys := mv.MapKeys()
+ for _, k := range keys {
+ mv.MapIndex(k)
+ }
+ }()
+ }
+ }
+ wg.Wait()
+ }
+ }
+}
+
+func TestConcurrentReadsAfterGrowth(t *testing.T) {
+ testConcurrentReadsAfterGrowth(t, false)
+}
+
+func TestConcurrentReadsAfterGrowthReflect(t *testing.T) {
+ testConcurrentReadsAfterGrowth(t, true)
+}
+
+func TestBigItems(t *testing.T) {
+ var key [256]string
+ for i := 0; i < 256; i++ {
+ key[i] = "foo"
+ }
+ m := make(map[[256]string][256]string, 4)
+ for i := 0; i < 100; i++ {
+ key[37] = fmt.Sprintf("string%02d", i)
+ m[key] = key
+ }
+ var keys [100]string
+ var values [100]string
+ i := 0
+ for k, v := range m {
+ keys[i] = k[37]
+ values[i] = v[37]
+ i++
+ }
+ sort.Strings(keys[:])
+ sort.Strings(values[:])
+ for i := 0; i < 100; i++ {
+ if keys[i] != fmt.Sprintf("string%02d", i) {
+ t.Errorf("#%d: missing key: %v", i, keys[i])
+ }
+ if values[i] != fmt.Sprintf("string%02d", i) {
+ t.Errorf("#%d: missing value: %v", i, values[i])
+ }
+ }
+}
+
+type empty struct {
+}
+
+func TestEmptyKeyAndValue(t *testing.T) {
+ a := make(map[int]empty, 4)
+ b := make(map[empty]int, 4)
+ c := make(map[empty]empty, 4)
+ a[0] = empty{}
+ b[empty{}] = 0
+ b[empty{}] = 1
+ c[empty{}] = empty{}
+
+ if len(a) != 1 {
+ t.Errorf("empty value insert problem")
+ }
+ if b[empty{}] != 1 {
+ t.Errorf("empty key returned wrong value")
+ }
+}
+
+// Tests a map with a single bucket, with same-lengthed short keys
+// ("quick keys") as well as long keys.
+func TestSingleBucketMapStringKeys_DupLen(t *testing.T) {
+ testMapLookups(t, map[string]string{
+ "x": "x1val",
+ "xx": "x2val",
+ "foo": "fooval",
+ "bar": "barval", // same key length as "foo"
+ "xxxx": "x4val",
+ strings.Repeat("x", 128): "longval1",
+ strings.Repeat("y", 128): "longval2",
+ })
+}
+
+// Tests a map with a single bucket, with all keys having different lengths.
+func TestSingleBucketMapStringKeys_NoDupLen(t *testing.T) {
+ testMapLookups(t, map[string]string{
+ "x": "x1val",
+ "xx": "x2val",
+ "foo": "fooval",
+ "xxxx": "x4val",
+ "xxxxx": "x5val",
+ "xxxxxx": "x6val",
+ strings.Repeat("x", 128): "longval",
+ })
+}
+
+func testMapLookups(t *testing.T, m map[string]string) {
+ for k, v := range m {
+ if m[k] != v {
+ t.Fatalf("m[%q] = %q; want %q", k, m[k], v)
+ }
+ }
+}
+
+// Tests whether the iterator returns the right elements when
+// started in the middle of a grow, when the keys are NaNs.
+func TestMapNanGrowIterator(t *testing.T) {
+ m := make(map[float64]int)
+ nan := math.NaN()
+ const nBuckets = 16
+ // To fill nBuckets buckets takes LOAD * nBuckets keys.
+ nKeys := int(nBuckets * *runtime.HashLoad)
+
+ // Get map to full point with nan keys.
+ for i := 0; i < nKeys; i++ {
+ m[nan] = i
+ }
+ // Trigger grow
+ m[1.0] = 1
+ delete(m, 1.0)
+
+ // Run iterator
+ found := make(map[int]struct{})
+ for _, v := range m {
+ if v != -1 {
+ if _, repeat := found[v]; repeat {
+ t.Fatalf("repeat of value %d", v)
+ }
+ found[v] = struct{}{}
+ }
+ if len(found) == nKeys/2 {
+ // Halfway through iteration, finish grow.
+ for i := 0; i < nBuckets; i++ {
+ delete(m, 1.0)
+ }
+ }
+ }
+ if len(found) != nKeys {
+ t.Fatalf("missing value")
+ }
+}
+
+func TestMapIterOrder(t *testing.T) {
+ for _, n := range [...]int{3, 7, 9, 15} {
+ // Make m be {0: true, 1: true, ..., n-1: true}.
+ m := make(map[int]bool)
+ for i := 0; i < n; i++ {
+ m[i] = true
+ }
+ // Check that iterating over the map produces at least two different orderings.
+ ord := func() []int {
+ var s []int
+ for key := range m {
+ s = append(s, key)
+ }
+ return s
+ }
+ first := ord()
+ ok := false
+ for try := 0; try < 100; try++ {
+ if !reflect.DeepEqual(first, ord()) {
+ ok = true
+ break
+ }
+ }
+ if !ok {
+ t.Errorf("Map with n=%d elements had consistent iteration order: %v", n, first)
+ }
+ }
+}
+
+func TestMapStringBytesLookup(t *testing.T) {
+ // Use large string keys to avoid small-allocation coalescing,
+ // which can cause AllocsPerRun to report lower counts than it should.
+ m := map[string]int{
+ "1000000000000000000000000000000000000000000000000": 1,
+ "2000000000000000000000000000000000000000000000000": 2,
+ }
+ buf := []byte("1000000000000000000000000000000000000000000000000")
+ if x := m[string(buf)]; x != 1 {
+ t.Errorf(`m[string([]byte("1"))] = %d, want 1`, x)
+ }
+ buf[0] = '2'
+ if x := m[string(buf)]; x != 2 {
+ t.Errorf(`m[string([]byte("2"))] = %d, want 2`, x)
+ }
+
+ var x int
+ n := testing.AllocsPerRun(100, func() {
+ x += m[string(buf)]
+ })
+ if n != 0 {
+ t.Errorf("AllocsPerRun for m[string(buf)] = %v, want 0", n)
+ }
+
+ x = 0
+ n = testing.AllocsPerRun(100, func() {
+ y, ok := m[string(buf)]
+ if !ok {
+ panic("!ok")
+ }
+ x += y
+ })
+ if n != 0 {
+ t.Errorf("AllocsPerRun for x,ok = m[string(buf)] = %v, want 0", n)
+ }
+}