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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:14:23 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:14:23 +0000
commit73df946d56c74384511a194dd01dbe099584fd1a (patch)
treefd0bcea490dd81327ddfbb31e215439672c9a068 /src/strconv/ftoa_test.go
parentInitial commit. (diff)
downloadgolang-1.16-73df946d56c74384511a194dd01dbe099584fd1a.tar.xz
golang-1.16-73df946d56c74384511a194dd01dbe099584fd1a.zip
Adding upstream version 1.16.10.upstream/1.16.10upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/strconv/ftoa_test.go')
-rw-r--r--src/strconv/ftoa_test.go273
1 files changed, 273 insertions, 0 deletions
diff --git a/src/strconv/ftoa_test.go b/src/strconv/ftoa_test.go
new file mode 100644
index 0000000..99cca17
--- /dev/null
+++ b/src/strconv/ftoa_test.go
@@ -0,0 +1,273 @@
+// Copyright 2009 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 strconv_test
+
+import (
+ "math"
+ "math/rand"
+ . "strconv"
+ "testing"
+)
+
+type ftoaTest struct {
+ f float64
+ fmt byte
+ prec int
+ s string
+}
+
+func fdiv(a, b float64) float64 { return a / b }
+
+const (
+ below1e23 = 99999999999999974834176
+ above1e23 = 100000000000000008388608
+)
+
+var ftoatests = []ftoaTest{
+ {1, 'e', 5, "1.00000e+00"},
+ {1, 'f', 5, "1.00000"},
+ {1, 'g', 5, "1"},
+ {1, 'g', -1, "1"},
+ {1, 'x', -1, "0x1p+00"},
+ {1, 'x', 5, "0x1.00000p+00"},
+ {20, 'g', -1, "20"},
+ {20, 'x', -1, "0x1.4p+04"},
+ {1234567.8, 'g', -1, "1.2345678e+06"},
+ {1234567.8, 'x', -1, "0x1.2d687cccccccdp+20"},
+ {200000, 'g', -1, "200000"},
+ {200000, 'x', -1, "0x1.86ap+17"},
+ {200000, 'X', -1, "0X1.86AP+17"},
+ {2000000, 'g', -1, "2e+06"},
+
+ // g conversion and zero suppression
+ {400, 'g', 2, "4e+02"},
+ {40, 'g', 2, "40"},
+ {4, 'g', 2, "4"},
+ {.4, 'g', 2, "0.4"},
+ {.04, 'g', 2, "0.04"},
+ {.004, 'g', 2, "0.004"},
+ {.0004, 'g', 2, "0.0004"},
+ {.00004, 'g', 2, "4e-05"},
+ {.000004, 'g', 2, "4e-06"},
+
+ {0, 'e', 5, "0.00000e+00"},
+ {0, 'f', 5, "0.00000"},
+ {0, 'g', 5, "0"},
+ {0, 'g', -1, "0"},
+ {0, 'x', 5, "0x0.00000p+00"},
+
+ {-1, 'e', 5, "-1.00000e+00"},
+ {-1, 'f', 5, "-1.00000"},
+ {-1, 'g', 5, "-1"},
+ {-1, 'g', -1, "-1"},
+
+ {12, 'e', 5, "1.20000e+01"},
+ {12, 'f', 5, "12.00000"},
+ {12, 'g', 5, "12"},
+ {12, 'g', -1, "12"},
+
+ {123456700, 'e', 5, "1.23457e+08"},
+ {123456700, 'f', 5, "123456700.00000"},
+ {123456700, 'g', 5, "1.2346e+08"},
+ {123456700, 'g', -1, "1.234567e+08"},
+
+ {1.2345e6, 'e', 5, "1.23450e+06"},
+ {1.2345e6, 'f', 5, "1234500.00000"},
+ {1.2345e6, 'g', 5, "1.2345e+06"},
+
+ {1e23, 'e', 17, "9.99999999999999916e+22"},
+ {1e23, 'f', 17, "99999999999999991611392.00000000000000000"},
+ {1e23, 'g', 17, "9.9999999999999992e+22"},
+
+ {1e23, 'e', -1, "1e+23"},
+ {1e23, 'f', -1, "100000000000000000000000"},
+ {1e23, 'g', -1, "1e+23"},
+
+ {below1e23, 'e', 17, "9.99999999999999748e+22"},
+ {below1e23, 'f', 17, "99999999999999974834176.00000000000000000"},
+ {below1e23, 'g', 17, "9.9999999999999975e+22"},
+
+ {below1e23, 'e', -1, "9.999999999999997e+22"},
+ {below1e23, 'f', -1, "99999999999999970000000"},
+ {below1e23, 'g', -1, "9.999999999999997e+22"},
+
+ {above1e23, 'e', 17, "1.00000000000000008e+23"},
+ {above1e23, 'f', 17, "100000000000000008388608.00000000000000000"},
+ {above1e23, 'g', 17, "1.0000000000000001e+23"},
+
+ {above1e23, 'e', -1, "1.0000000000000001e+23"},
+ {above1e23, 'f', -1, "100000000000000010000000"},
+ {above1e23, 'g', -1, "1.0000000000000001e+23"},
+
+ {fdiv(5e-304, 1e20), 'g', -1, "5e-324"}, // avoid constant arithmetic
+ {fdiv(-5e-304, 1e20), 'g', -1, "-5e-324"}, // avoid constant arithmetic
+
+ {32, 'g', -1, "32"},
+ {32, 'g', 0, "3e+01"},
+
+ {100, 'x', -1, "0x1.9p+06"},
+ {100, 'y', -1, "%y"},
+
+ {math.NaN(), 'g', -1, "NaN"},
+ {-math.NaN(), 'g', -1, "NaN"},
+ {math.Inf(0), 'g', -1, "+Inf"},
+ {math.Inf(-1), 'g', -1, "-Inf"},
+ {-math.Inf(0), 'g', -1, "-Inf"},
+
+ {-1, 'b', -1, "-4503599627370496p-52"},
+
+ // fixed bugs
+ {0.9, 'f', 1, "0.9"},
+ {0.09, 'f', 1, "0.1"},
+ {0.0999, 'f', 1, "0.1"},
+ {0.05, 'f', 1, "0.1"},
+ {0.05, 'f', 0, "0"},
+ {0.5, 'f', 1, "0.5"},
+ {0.5, 'f', 0, "0"},
+ {1.5, 'f', 0, "2"},
+
+ // https://www.exploringbinary.com/java-hangs-when-converting-2-2250738585072012e-308/
+ {2.2250738585072012e-308, 'g', -1, "2.2250738585072014e-308"},
+ // https://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"},
+
+ // Issue 29491.
+ {498484681984085570, 'f', -1, "498484681984085570"},
+ {-5.8339553793802237e+23, 'g', -1, "-5.8339553793802237e+23"},
+
+ // rounding
+ {2.275555555555555, 'x', -1, "0x1.23456789abcdep+01"},
+ {2.275555555555555, 'x', 0, "0x1p+01"},
+ {2.275555555555555, 'x', 2, "0x1.23p+01"},
+ {2.275555555555555, 'x', 16, "0x1.23456789abcde000p+01"},
+ {2.275555555555555, 'x', 21, "0x1.23456789abcde00000000p+01"},
+ {2.2755555510520935, 'x', -1, "0x1.2345678p+01"},
+ {2.2755555510520935, 'x', 6, "0x1.234568p+01"},
+ {2.275555431842804, 'x', -1, "0x1.2345668p+01"},
+ {2.275555431842804, 'x', 6, "0x1.234566p+01"},
+ {3.999969482421875, 'x', -1, "0x1.ffffp+01"},
+ {3.999969482421875, 'x', 4, "0x1.ffffp+01"},
+ {3.999969482421875, 'x', 3, "0x1.000p+02"},
+ {3.999969482421875, 'x', 2, "0x1.00p+02"},
+ {3.999969482421875, 'x', 1, "0x1.0p+02"},
+ {3.999969482421875, 'x', 0, "0x1p+02"},
+}
+
+func TestFtoa(t *testing.T) {
+ for i := 0; i < len(ftoatests); i++ {
+ test := &ftoatests[i]
+ 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 := 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)
+ }
+
+ prec := rand.Intn(12) + 5
+ shortFast = FormatFloat(x, 'e', prec, 64)
+ SetOptimize(false)
+ shortSlow = FormatFloat(x, 'e', prec, 64)
+ SetOptimize(true)
+ if shortSlow != shortFast {
+ t.Errorf("%b printed as %s, want %s", x, shortFast, shortSlow)
+ }
+ }
+}
+
+func TestFormatFloatInvalidBitSize(t *testing.T) {
+ defer func() {
+ if r := recover(); r == nil {
+ t.Fatalf("expected panic due to invalid bitSize")
+ }
+ }()
+ _ = FormatFloat(3.14, 'g', -1, 100)
+}
+
+var ftoaBenches = []struct {
+ name string
+ float float64
+ fmt byte
+ prec int
+ bitSize int
+}{
+ {"Decimal", 33909, 'g', -1, 64},
+ {"Float", 339.7784, 'g', -1, 64},
+ {"Exp", -5.09e75, 'g', -1, 64},
+ {"NegExp", -5.11e-95, 'g', -1, 64},
+
+ {"Big", 123456789123456789123456789, 'g', -1, 64},
+ {"BinaryExp", -1, 'b', -1, 64},
+
+ {"32Integer", 33909, 'g', -1, 32},
+ {"32ExactFraction", 3.375, 'g', -1, 32},
+ {"32Point", 339.7784, 'g', -1, 32},
+ {"32Exp", -5.09e25, 'g', -1, 32},
+ {"32NegExp", -5.11e-25, 'g', -1, 32},
+
+ {"64Fixed1", 123456, 'e', 3, 64},
+ {"64Fixed2", 123.456, 'e', 3, 64},
+ {"64Fixed3", 1.23456e+78, 'e', 3, 64},
+ {"64Fixed4", 1.23456e-78, 'e', 3, 64},
+
+ // Trigger slow path (see issue #15672).
+ {"Slowpath64", 622666234635.3213e-320, 'e', -1, 64},
+}
+
+func BenchmarkFormatFloat(b *testing.B) {
+ for _, c := range ftoaBenches {
+ b.Run(c.name, func(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ FormatFloat(c.float, c.fmt, c.prec, c.bitSize)
+ }
+ })
+ }
+}
+
+func BenchmarkAppendFloat(b *testing.B) {
+ dst := make([]byte, 30)
+ for _, c := range ftoaBenches {
+ b.Run(c.name, func(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ AppendFloat(dst[:0], c.float, c.fmt, c.prec, c.bitSize)
+ }
+ })
+ }
+}