diff options
Diffstat (limited to 'src/pkg/strconv/ftoa_test.go')
| -rw-r--r-- | src/pkg/strconv/ftoa_test.go | 126 |
1 files changed, 116 insertions, 10 deletions
diff --git a/src/pkg/strconv/ftoa_test.go b/src/pkg/strconv/ftoa_test.go index 6d361a138..7d8617a85 100644 --- a/src/pkg/strconv/ftoa_test.go +++ b/src/pkg/strconv/ftoa_test.go @@ -6,6 +6,7 @@ package strconv_test import ( "math" + "math/rand" . "strconv" "testing" ) @@ -123,28 +124,133 @@ var ftoatests = []ftoaTest{ {2.2250738585072012e-308, 'g', -1, "2.2250738585072014e-308"}, // http://www.exploringbinary.com/php-hangs-on-numeric-value-2-2250738585072011e-308/ {2.2250738585072011e-308, 'g', -1, "2.225073858507201e-308"}, + + // Issue 2625. + {383260575764816448, 'f', 0, "383260575764816448"}, + {383260575764816448, 'g', -1, "3.8326057576481645e+17"}, } func TestFtoa(t *testing.T) { for i := 0; i < len(ftoatests); i++ { test := &ftoatests[i] - s := Ftoa64(test.f, test.fmt, test.prec) - if s != test.s { - t.Error("test", test.f, string(test.fmt), test.prec, "want", test.s, "got", s) - } - s = FtoaN(test.f, test.fmt, test.prec, 64) + s := FormatFloat(test.f, test.fmt, test.prec, 64) if s != test.s { t.Error("testN=64", test.f, string(test.fmt), test.prec, "want", test.s, "got", s) } + x := AppendFloat([]byte("abc"), test.f, test.fmt, test.prec, 64) + if string(x) != "abc"+test.s { + t.Error("AppendFloat testN=64", test.f, string(test.fmt), test.prec, "want", "abc"+test.s, "got", string(x)) + } if float64(float32(test.f)) == test.f && test.fmt != 'b' { - s := Ftoa32(float32(test.f), test.fmt, test.prec) - if s != test.s { - t.Error("test32", test.f, string(test.fmt), test.prec, "want", test.s, "got", s) - } - s = FtoaN(test.f, test.fmt, test.prec, 32) + s := FormatFloat(test.f, test.fmt, test.prec, 32) if s != test.s { t.Error("testN=32", test.f, string(test.fmt), test.prec, "want", test.s, "got", s) } + x := AppendFloat([]byte("abc"), test.f, test.fmt, test.prec, 32) + if string(x) != "abc"+test.s { + t.Error("AppendFloat testN=32", test.f, string(test.fmt), test.prec, "want", "abc"+test.s, "got", string(x)) + } + } + } +} + +func TestFtoaRandom(t *testing.T) { + N := int(1e4) + if testing.Short() { + N = 100 + } + t.Logf("testing %d random numbers with fast and slow FormatFloat", N) + for i := 0; i < N; i++ { + bits := uint64(rand.Uint32())<<32 | uint64(rand.Uint32()) + x := math.Float64frombits(bits) + shortFast := FormatFloat(x, 'g', -1, 64) + SetOptimize(false) + shortSlow := FormatFloat(x, 'g', -1, 64) + SetOptimize(true) + if shortSlow != shortFast { + t.Errorf("%b printed as %s, want %s", x, shortFast, shortSlow) } } } + +func TestAppendFloatDoesntAllocate(t *testing.T) { + n := numAllocations(func() { + var buf [64]byte + AppendFloat(buf[:0], 1.23, 'g', 5, 64) + }) + want := 1 // TODO(bradfitz): this might be 0, once escape analysis is better + if n != want { + t.Errorf("with local buffer, did %d allocations, want %d", n, want) + } + n = numAllocations(func() { + AppendFloat(globalBuf[:0], 1.23, 'g', 5, 64) + }) + if n != 0 { + t.Errorf("with reused buffer, did %d allocations, want 0", n) + } +} + +func BenchmarkFormatFloatDecimal(b *testing.B) { + for i := 0; i < b.N; i++ { + FormatFloat(33909, 'g', -1, 64) + } +} + +func BenchmarkFormatFloat(b *testing.B) { + for i := 0; i < b.N; i++ { + FormatFloat(339.7784, 'g', -1, 64) + } +} + +func BenchmarkFormatFloatExp(b *testing.B) { + for i := 0; i < b.N; i++ { + FormatFloat(-5.09e75, 'g', -1, 64) + } +} + +func BenchmarkFormatFloatNegExp(b *testing.B) { + for i := 0; i < b.N; i++ { + FormatFloat(-5.11e-95, 'g', -1, 64) + } +} + +func BenchmarkFormatFloatBig(b *testing.B) { + for i := 0; i < b.N; i++ { + FormatFloat(123456789123456789123456789, 'g', -1, 64) + } +} + +func BenchmarkAppendFloatDecimal(b *testing.B) { + dst := make([]byte, 0, 30) + for i := 0; i < b.N; i++ { + AppendFloat(dst, 33909, 'g', -1, 64) + } +} + +func BenchmarkAppendFloat(b *testing.B) { + dst := make([]byte, 0, 30) + for i := 0; i < b.N; i++ { + AppendFloat(dst, 339.7784, 'g', -1, 64) + } +} + +func BenchmarkAppendFloatExp(b *testing.B) { + dst := make([]byte, 0, 30) + for i := 0; i < b.N; i++ { + AppendFloat(dst, -5.09e75, 'g', -1, 64) + } +} + +func BenchmarkAppendFloatNegExp(b *testing.B) { + dst := make([]byte, 0, 30) + for i := 0; i < b.N; i++ { + AppendFloat(dst, -5.11e-95, 'g', -1, 64) + } +} + +func BenchmarkAppendFloatBig(b *testing.B) { + dst := make([]byte, 0, 30) + for i := 0; i < b.N; i++ { + AppendFloat(dst, 123456789123456789123456789, 'g', -1, 64) + } +} |