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Diffstat (limited to 'libgo/go/math/big/floatconv_test.go')
-rw-r--r-- | libgo/go/math/big/floatconv_test.go | 573 |
1 files changed, 573 insertions, 0 deletions
diff --git a/libgo/go/math/big/floatconv_test.go b/libgo/go/math/big/floatconv_test.go new file mode 100644 index 00000000000..4f239534a14 --- /dev/null +++ b/libgo/go/math/big/floatconv_test.go @@ -0,0 +1,573 @@ +// Copyright 2015 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 big + +import ( + "fmt" + "math" + "strconv" + "testing" +) + +func TestFloatSetFloat64String(t *testing.T) { + inf := math.Inf(0) + nan := math.NaN() + + for _, test := range []struct { + s string + x float64 // NaNs represent invalid inputs + }{ + // basics + {"0", 0}, + {"-0", -0}, + {"+0", 0}, + {"1", 1}, + {"-1", -1}, + {"+1", 1}, + {"1.234", 1.234}, + {"-1.234", -1.234}, + {"+1.234", 1.234}, + {".1", 0.1}, + {"1.", 1}, + {"+1.", 1}, + + // various zeros + {"0e100", 0}, + {"-0e+100", 0}, + {"+0e-100", 0}, + {"0E100", 0}, + {"-0E+100", 0}, + {"+0E-100", 0}, + + // various decimal exponent formats + {"1.e10", 1e10}, + {"1e+10", 1e10}, + {"+1e-10", 1e-10}, + {"1E10", 1e10}, + {"1.E+10", 1e10}, + {"+1E-10", 1e-10}, + + // infinities + {"Inf", inf}, + {"+Inf", inf}, + {"-Inf", -inf}, + {"inf", inf}, + {"+inf", inf}, + {"-inf", -inf}, + + // invalid numbers + {"", nan}, + {"-", nan}, + {"0x", nan}, + {"0e", nan}, + {"1.2ef", nan}, + {"2..3", nan}, + {"123..", nan}, + {"infinity", nan}, + {"foobar", nan}, + + // misc decimal values + {"3.14159265", 3.14159265}, + {"-687436.79457e-245", -687436.79457e-245}, + {"-687436.79457E245", -687436.79457e245}, + {".0000000000000000000000000000000000000001", 1e-40}, + {"+10000000000000000000000000000000000000000e-0", 1e40}, + + // decimal mantissa, binary exponent + {"0p0", 0}, + {"-0p0", -0}, + {"1p10", 1 << 10}, + {"1p+10", 1 << 10}, + {"+1p-10", 1.0 / (1 << 10)}, + {"1024p-12", 0.25}, + {"-1p10", -1024}, + {"1.5p1", 3}, + + // binary mantissa, decimal exponent + {"0b0", 0}, + {"-0b0", -0}, + {"0b0e+10", 0}, + {"-0b0e-10", -0}, + {"0b1010", 10}, + {"0B1010E2", 1000}, + {"0b.1", 0.5}, + {"0b.001", 0.125}, + {"0b.001e3", 125}, + + // binary mantissa, binary exponent + {"0b0p+10", 0}, + {"-0b0p-10", -0}, + {"0b.1010p4", 10}, + {"0b1p-1", 0.5}, + {"0b001p-3", 0.125}, + {"0b.001p3", 1}, + {"0b0.01p2", 1}, + + // hexadecimal mantissa and exponent + {"0x0", 0}, + {"-0x0", -0}, + {"0x0p+10", 0}, + {"-0x0p-10", -0}, + {"0xff", 255}, + {"0X.8p1", 1}, + {"-0X0.00008p16", -0.5}, + {"0x0.0000000000001p-1022", math.SmallestNonzeroFloat64}, + {"0x1.fffffffffffffp1023", math.MaxFloat64}, + } { + var x Float + x.SetPrec(53) + _, ok := x.SetString(test.s) + if math.IsNaN(test.x) { + // test.s is invalid + if ok { + t.Errorf("%s: want parse error", test.s) + } + continue + } + // test.s is valid + if !ok { + t.Errorf("%s: got parse error", test.s) + continue + } + f, _ := x.Float64() + want := new(Float).SetFloat64(test.x) + if x.Cmp(want) != 0 { + t.Errorf("%s: got %s (%v); want %v", test.s, &x, f, test.x) + } + } +} + +const ( + below1e23 = 99999999999999974834176 + above1e23 = 100000000000000008388608 +) + +func TestFloat64Text(t *testing.T) { + for _, test := range []struct { + x float64 + format byte + prec int + want string + }{ + {0, 'f', 0, "0"}, + {math.Copysign(0, -1), 'f', 0, "-0"}, + {1, 'f', 0, "1"}, + {-1, 'f', 0, "-1"}, + + {0.001, 'e', 0, "1e-03"}, + {0.459, 'e', 0, "5e-01"}, + {1.459, 'e', 0, "1e+00"}, + {2.459, 'e', 1, "2.5e+00"}, + {3.459, 'e', 2, "3.46e+00"}, + {4.459, 'e', 3, "4.459e+00"}, + {5.459, 'e', 4, "5.4590e+00"}, + + {0.001, 'f', 0, "0"}, + {0.459, 'f', 0, "0"}, + {1.459, 'f', 0, "1"}, + {2.459, 'f', 1, "2.5"}, + {3.459, 'f', 2, "3.46"}, + {4.459, 'f', 3, "4.459"}, + {5.459, 'f', 4, "5.4590"}, + + {0, 'b', 0, "0"}, + {math.Copysign(0, -1), 'b', 0, "-0"}, + {1.0, 'b', 0, "4503599627370496p-52"}, + {-1.0, 'b', 0, "-4503599627370496p-52"}, + {4503599627370496, 'b', 0, "4503599627370496p+0"}, + + {0, 'p', 0, "0"}, + {math.Copysign(0, -1), 'p', 0, "-0"}, + {1024.0, 'p', 0, "0x.8p+11"}, + {-1024.0, 'p', 0, "-0x.8p+11"}, + + // all test cases below from strconv/ftoa_test.go + {1, 'e', 5, "1.00000e+00"}, + {1, 'f', 5, "1.00000"}, + {1, 'g', 5, "1"}, + // {1, 'g', -1, "1"}, + // {20, 'g', -1, "20"}, + // {1234567.8, 'g', -1, "1.2345678e+06"}, + // {200000, 'g', -1, "200000"}, + // {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"}, + + {-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"}, + // {fdiv(-5e-304, 1e20), 'g', -1, "-5e-324"}, + + // {32, 'g', -1, "32"}, + // {32, 'g', 0, "3e+01"}, + + // {100, 'x', -1, "%x"}, + + // {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"}, + + // http://www.exploringbinary.com/java-hangs-when-converting-2-2250738585072012e-308/ + // {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"}, + } { + f := new(Float).SetFloat64(test.x) + got := f.Text(test.format, test.prec) + if got != test.want { + t.Errorf("%v: got %s; want %s", test, got, test.want) + } + + if test.format == 'b' && test.x == 0 { + continue // 'b' format in strconv.Float requires knowledge of bias for 0.0 + } + if test.format == 'p' { + continue // 'p' format not supported in strconv.Format + } + + // verify that Float format matches strconv format + want := strconv.FormatFloat(test.x, test.format, test.prec, 64) + if got != want { + t.Errorf("%v: got %s; want %s (strconv)", test, got, want) + } + } +} + +func TestFloatText(t *testing.T) { + for _, test := range []struct { + x string + prec uint + format byte + digits int + want string + }{ + {"0", 10, 'f', 0, "0"}, + {"-0", 10, 'f', 0, "-0"}, + {"1", 10, 'f', 0, "1"}, + {"-1", 10, 'f', 0, "-1"}, + + {"1.459", 100, 'e', 0, "1e+00"}, + {"2.459", 100, 'e', 1, "2.5e+00"}, + {"3.459", 100, 'e', 2, "3.46e+00"}, + {"4.459", 100, 'e', 3, "4.459e+00"}, + {"5.459", 100, 'e', 4, "5.4590e+00"}, + + {"1.459", 100, 'E', 0, "1E+00"}, + {"2.459", 100, 'E', 1, "2.5E+00"}, + {"3.459", 100, 'E', 2, "3.46E+00"}, + {"4.459", 100, 'E', 3, "4.459E+00"}, + {"5.459", 100, 'E', 4, "5.4590E+00"}, + + {"1.459", 100, 'f', 0, "1"}, + {"2.459", 100, 'f', 1, "2.5"}, + {"3.459", 100, 'f', 2, "3.46"}, + {"4.459", 100, 'f', 3, "4.459"}, + {"5.459", 100, 'f', 4, "5.4590"}, + + {"1.459", 100, 'g', 0, "1"}, + {"2.459", 100, 'g', 1, "2"}, + {"3.459", 100, 'g', 2, "3.5"}, + {"4.459", 100, 'g', 3, "4.46"}, + {"5.459", 100, 'g', 4, "5.459"}, + + {"1459", 53, 'g', 0, "1e+03"}, + {"2459", 53, 'g', 1, "2e+03"}, + {"3459", 53, 'g', 2, "3.5e+03"}, + {"4459", 53, 'g', 3, "4.46e+03"}, + {"5459", 53, 'g', 4, "5459"}, + + {"1459", 53, 'G', 0, "1E+03"}, + {"2459", 53, 'G', 1, "2E+03"}, + {"3459", 53, 'G', 2, "3.5E+03"}, + {"4459", 53, 'G', 3, "4.46E+03"}, + {"5459", 53, 'G', 4, "5459"}, + + {"3", 10, 'e', 40, "3.0000000000000000000000000000000000000000e+00"}, + {"3", 10, 'f', 40, "3.0000000000000000000000000000000000000000"}, + {"3", 10, 'g', 40, "3"}, + + {"3e40", 100, 'e', 40, "3.0000000000000000000000000000000000000000e+40"}, + {"3e40", 100, 'f', 4, "30000000000000000000000000000000000000000.0000"}, + {"3e40", 100, 'g', 40, "3e+40"}, + + // make sure "stupid" exponents don't stall the machine + {"1e1000000", 64, 'p', 0, "0x.88b3a28a05eade3ap+3321929"}, + {"1e1000000000", 64, 'p', 0, "0x.ecc5f45aa573d3p+1538481529"}, + {"1e-1000000", 64, 'p', 0, "0x.efb4542cc8ca418ap-3321928"}, + {"1e-1000000000", 64, 'p', 0, "0x.8a64dd983a4c7dabp-1538481528"}, + + // TODO(gri) need tests for actual large Floats + + {"0", 53, 'b', 0, "0"}, + {"-0", 53, 'b', 0, "-0"}, + {"1.0", 53, 'b', 0, "4503599627370496p-52"}, + {"-1.0", 53, 'b', 0, "-4503599627370496p-52"}, + {"4503599627370496", 53, 'b', 0, "4503599627370496p+0"}, + + // issue 9939 + {"3", 350, 'b', 0, "1720123961992553633708115671476565205597423741876210842803191629540192157066363606052513914832594264915968p-348"}, + {"03", 350, 'b', 0, "1720123961992553633708115671476565205597423741876210842803191629540192157066363606052513914832594264915968p-348"}, + {"3.", 350, 'b', 0, "1720123961992553633708115671476565205597423741876210842803191629540192157066363606052513914832594264915968p-348"}, + {"3.0", 350, 'b', 0, "1720123961992553633708115671476565205597423741876210842803191629540192157066363606052513914832594264915968p-348"}, + {"3.00", 350, 'b', 0, "1720123961992553633708115671476565205597423741876210842803191629540192157066363606052513914832594264915968p-348"}, + {"3.000", 350, 'b', 0, "1720123961992553633708115671476565205597423741876210842803191629540192157066363606052513914832594264915968p-348"}, + + {"3", 350, 'p', 0, "0x.cp+2"}, + {"03", 350, 'p', 0, "0x.cp+2"}, + {"3.", 350, 'p', 0, "0x.cp+2"}, + {"3.0", 350, 'p', 0, "0x.cp+2"}, + {"3.00", 350, 'p', 0, "0x.cp+2"}, + {"3.000", 350, 'p', 0, "0x.cp+2"}, + + {"0", 64, 'p', 0, "0"}, + {"-0", 64, 'p', 0, "-0"}, + {"1024.0", 64, 'p', 0, "0x.8p+11"}, + {"-1024.0", 64, 'p', 0, "-0x.8p+11"}, + + // unsupported format + {"3.14", 64, 'x', 0, "%x"}, + {"-3.14", 64, 'x', 0, "%x"}, + } { + f, _, err := ParseFloat(test.x, 0, test.prec, ToNearestEven) + if err != nil { + t.Errorf("%v: %s", test, err) + continue + } + + got := f.Text(test.format, test.digits) + if got != test.want { + t.Errorf("%v: got %s; want %s", test, got, test.want) + } + + // compare with strconv.FormatFloat output if possible + // ('p' format is not supported by strconv.FormatFloat, + // and its output for 0.0 prints a biased exponent value + // as in 0p-1074 which makes no sense to emulate here) + if test.prec == 53 && test.format != 'p' && f.Sign() != 0 { + f64, acc := f.Float64() + if acc != Exact { + t.Errorf("%v: expected exact conversion to float64", test) + continue + } + got := strconv.FormatFloat(f64, test.format, test.digits, 64) + if got != test.want { + t.Errorf("%v: got %s; want %s", test, got, test.want) + } + } + } +} + +func TestFloatFormat(t *testing.T) { + for _, test := range []struct { + format string + value interface{} // float32, float64, or string (== 512bit *Float) + want string + }{ + // TODO(gri) uncomment the disabled 'g'/'G' formats + // below once (*Float).Text supports prec < 0 + + // from fmt/fmt_test.go + {"%+.3e", 0.0, "+0.000e+00"}, + {"%+.3e", 1.0, "+1.000e+00"}, + {"%+.3f", -1.0, "-1.000"}, + {"%+.3F", -1.0, "-1.000"}, + {"%+.3F", float32(-1.0), "-1.000"}, + {"%+07.2f", 1.0, "+001.00"}, + {"%+07.2f", -1.0, "-001.00"}, + {"%+10.2f", +1.0, " +1.00"}, + {"%+10.2f", -1.0, " -1.00"}, + {"% .3E", -1.0, "-1.000E+00"}, + {"% .3e", 1.0, " 1.000e+00"}, + {"%+.3g", 0.0, "+0"}, + {"%+.3g", 1.0, "+1"}, + {"%+.3g", -1.0, "-1"}, + {"% .3g", -1.0, "-1"}, + {"% .3g", 1.0, " 1"}, + {"%b", float32(1.0), "8388608p-23"}, + {"%b", 1.0, "4503599627370496p-52"}, + + // from fmt/fmt_test.go: old test/fmt_test.go + {"%e", 1.0, "1.000000e+00"}, + {"%e", 1234.5678e3, "1.234568e+06"}, + {"%e", 1234.5678e-8, "1.234568e-05"}, + {"%e", -7.0, "-7.000000e+00"}, + {"%e", -1e-9, "-1.000000e-09"}, + {"%f", 1234.5678e3, "1234567.800000"}, + {"%f", 1234.5678e-8, "0.000012"}, + {"%f", -7.0, "-7.000000"}, + {"%f", -1e-9, "-0.000000"}, + // {"%g", 1234.5678e3, "1.2345678e+06"}, + // {"%g", float32(1234.5678e3), "1.2345678e+06"}, + // {"%g", 1234.5678e-8, "1.2345678e-05"}, + {"%g", -7.0, "-7"}, + {"%g", -1e-9, "-1e-09"}, + {"%g", float32(-1e-9), "-1e-09"}, + {"%E", 1.0, "1.000000E+00"}, + {"%E", 1234.5678e3, "1.234568E+06"}, + {"%E", 1234.5678e-8, "1.234568E-05"}, + {"%E", -7.0, "-7.000000E+00"}, + {"%E", -1e-9, "-1.000000E-09"}, + // {"%G", 1234.5678e3, "1.2345678E+06"}, + // {"%G", float32(1234.5678e3), "1.2345678E+06"}, + // {"%G", 1234.5678e-8, "1.2345678E-05"}, + {"%G", -7.0, "-7"}, + {"%G", -1e-9, "-1E-09"}, + {"%G", float32(-1e-9), "-1E-09"}, + + {"%20.6e", 1.2345e3, " 1.234500e+03"}, + {"%20.6e", 1.2345e-3, " 1.234500e-03"}, + {"%20e", 1.2345e3, " 1.234500e+03"}, + {"%20e", 1.2345e-3, " 1.234500e-03"}, + {"%20.8e", 1.2345e3, " 1.23450000e+03"}, + {"%20f", 1.23456789e3, " 1234.567890"}, + {"%20f", 1.23456789e-3, " 0.001235"}, + {"%20f", 12345678901.23456789, " 12345678901.234568"}, + {"%-20f", 1.23456789e3, "1234.567890 "}, + {"%20.8f", 1.23456789e3, " 1234.56789000"}, + {"%20.8f", 1.23456789e-3, " 0.00123457"}, + // {"%g", 1.23456789e3, "1234.56789"}, + // {"%g", 1.23456789e-3, "0.00123456789"}, + // {"%g", 1.23456789e20, "1.23456789e+20"}, + {"%20e", math.Inf(1), " +Inf"}, + {"%-20f", math.Inf(-1), "-Inf "}, + + // from fmt/fmt_test.go: comparison of padding rules with C printf + {"%.2f", 1.0, "1.00"}, + {"%.2f", -1.0, "-1.00"}, + {"% .2f", 1.0, " 1.00"}, + {"% .2f", -1.0, "-1.00"}, + {"%+.2f", 1.0, "+1.00"}, + {"%+.2f", -1.0, "-1.00"}, + {"%7.2f", 1.0, " 1.00"}, + {"%7.2f", -1.0, " -1.00"}, + {"% 7.2f", 1.0, " 1.00"}, + {"% 7.2f", -1.0, " -1.00"}, + {"%+7.2f", 1.0, " +1.00"}, + {"%+7.2f", -1.0, " -1.00"}, + {"%07.2f", 1.0, "0001.00"}, + {"%07.2f", -1.0, "-001.00"}, + {"% 07.2f", 1.0, " 001.00"}, + {"% 07.2f", -1.0, "-001.00"}, + {"%+07.2f", 1.0, "+001.00"}, + {"%+07.2f", -1.0, "-001.00"}, + + // from fmt/fmt_test.go: zero padding does not apply to infinities + {"%020f", math.Inf(-1), " -Inf"}, + {"%020f", math.Inf(+1), " +Inf"}, + {"% 020f", math.Inf(-1), " -Inf"}, + {"% 020f", math.Inf(+1), " Inf"}, + {"%+020f", math.Inf(-1), " -Inf"}, + {"%+020f", math.Inf(+1), " +Inf"}, + {"%20f", -1.0, " -1.000000"}, + + // handle %v like %g + {"%v", 0.0, "0"}, + {"%v", -7.0, "-7"}, + {"%v", -1e-9, "-1e-09"}, + {"%v", float32(-1e-9), "-1e-09"}, + {"%010v", 0.0, "0000000000"}, + {"%010v", 0.0, "0000000000"}, + + // *Float cases + {"%.20f", "1e-20", "0.00000000000000000001"}, + {"%.20f", "-1e-20", "-0.00000000000000000001"}, + {"%30.20f", "-1e-20", " -0.00000000000000000001"}, + {"%030.20f", "-1e-20", "-00000000.00000000000000000001"}, + {"%030.20f", "+1e-20", "000000000.00000000000000000001"}, + {"% 030.20f", "+1e-20", " 00000000.00000000000000000001"}, + + // erroneous formats + {"%s", 1.0, "%!s(*big.Float=1)"}, + } { + value := new(Float) + switch v := test.value.(type) { + case float32: + value.SetPrec(24).SetFloat64(float64(v)) + case float64: + value.SetPrec(53).SetFloat64(v) + case string: + value.SetPrec(512).Parse(v, 0) + default: + t.Fatalf("unsupported test value: %v (%T)", v, v) + } + + if got := fmt.Sprintf(test.format, value); got != test.want { + t.Errorf("%v: got %q; want %q", test, got, test.want) + } + } +} |