out: []intWithPtrMarshalText{1, 2, 3},
golden: true,
},
+
+ {in: `0.000001`, ptr: new(float64), out: 0.000001, golden: true},
+ {in: `1e-7`, ptr: new(float64), out: 1e-7, golden: true},
+ {in: `100000000000000000000`, ptr: new(float64), out: 100000000000000000000.0, golden: true},
+ {in: `1e+21`, ptr: new(float64), out: 1e21, golden: true},
+ {in: `-0.000001`, ptr: new(float64), out: -0.000001, golden: true},
+ {in: `-1e-7`, ptr: new(float64), out: -1e-7, golden: true},
+ {in: `-100000000000000000000`, ptr: new(float64), out: -100000000000000000000.0, golden: true},
+ {in: `-1e+21`, ptr: new(float64), out: -1e21, golden: true},
+ {in: `999999999999999900000`, ptr: new(float64), out: 999999999999999900000.0, golden: true},
+ {in: `9007199254740992`, ptr: new(float64), out: 9007199254740992.0, golden: true},
+ {in: `9007199254740993`, ptr: new(float64), out: 9007199254740992.0, golden: false},
}
func TestMarshal(t *testing.T) {
if math.IsInf(f, 0) || math.IsNaN(f) {
e.error(&UnsupportedValueError{v, strconv.FormatFloat(f, 'g', -1, int(bits))})
}
- b := strconv.AppendFloat(e.scratch[:0], f, 'g', -1, int(bits))
+
+ // Convert as if by ES6 number to string conversion.
+ // This matches most other JSON generators.
+ // See golang.org/issue/6384 and golang.org/issue/14135.
+ // Like fmt %g, but the exponent cutoffs are different
+ // and exponents themselves are not padded to two digits.
+ b := e.scratch[:0]
+ abs := math.Abs(f)
+ fmt := byte('f')
+ // Note: Must use float32 comparisons for underlying float32 value to get precise cutoffs right.
+ if abs != 0 {
+ if bits == 64 && (abs < 1e-6 || abs >= 1e21) || bits == 32 && (float32(abs) < 1e-6 || float32(abs) >= 1e21) {
+ fmt = 'e'
+ }
+ }
+ b = strconv.AppendFloat(b, f, fmt, -1, int(bits))
+ if fmt == 'e' {
+ // clean up e-09 to e-9
+ n := len(b)
+ if n >= 4 && b[n-4] == 'e' && b[n-3] == '-' && b[n-2] == '0' {
+ b[n-2] = b[n-1]
+ b = b[:n-1]
+ }
+ }
+
if opts.quoted {
e.WriteByte('"')
}
import (
"bytes"
"fmt"
+ "log"
"math"
"reflect"
+ "regexp"
+ "strconv"
"testing"
"unicode"
)
t.Errorf("Marshal map with text.Marshaler keys: got %#q, want %#q", b, want)
}
}
+
+var re = regexp.MustCompile
+
+// syntactic checks on form of marshalled floating point numbers.
+var badFloatREs = []*regexp.Regexp{
+ re(`p`), // no binary exponential notation
+ re(`^\+`), // no leading + sign
+ re(`^-?0[^.]`), // no unnecessary leading zeros
+ re(`^-?\.`), // leading zero required before decimal point
+ re(`\.(e|$)`), // no trailing decimal
+ re(`\.[0-9]+0(e|$)`), // no trailing zero in fraction
+ re(`^-?(0|[0-9]{2,})\..*e`), // exponential notation must have normalized mantissa
+ re(`e[0-9]`), // positive exponent must be signed
+ re(`e[+-]0`), // exponent must not have leading zeros
+ re(`e-[1-6]$`), // not tiny enough for exponential notation
+ re(`e+(.|1.|20)$`), // not big enough for exponential notation
+ re(`^-?0\.0000000`), // too tiny, should use exponential notation
+ re(`^-?[0-9]{22}`), // too big, should use exponential notation
+ re(`[1-9][0-9]{16}[1-9]`), // too many significant digits in integer
+ re(`[1-9][0-9.]{17}[1-9]`), // too many significant digits in decimal
+ // below here for float32 only
+ re(`[1-9][0-9]{8}[1-9]`), // too many significant digits in integer
+ re(`[1-9][0-9.]{9}[1-9]`), // too many significant digits in decimal
+}
+
+func TestMarshalFloat(t *testing.T) {
+ nfail := 0
+ test := func(f float64, bits int) {
+ vf := interface{}(f)
+ if bits == 32 {
+ f = float64(float32(f)) // round
+ vf = float32(f)
+ }
+ bout, err := Marshal(vf)
+ if err != nil {
+ t.Errorf("Marshal(%T(%g)): %v", vf, vf, err)
+ nfail++
+ return
+ }
+ out := string(bout)
+
+ // result must convert back to the same float
+ g, err := strconv.ParseFloat(out, bits)
+ if err != nil {
+ t.Errorf("Marshal(%T(%g)) = %q, cannot parse back: %v", vf, vf, out, err)
+ nfail++
+ return
+ }
+ if f != g || fmt.Sprint(f) != fmt.Sprint(g) { // fmt.Sprint handles ±0
+ t.Errorf("Marshal(%T(%g)) = %q (is %g, not %g)", vf, vf, out, float32(g), vf)
+ nfail++
+ return
+ }
+
+ bad := badFloatREs
+ if bits == 64 {
+ bad = bad[:len(bad)-2]
+ }
+ for _, re := range bad {
+ if re.MatchString(out) {
+ t.Errorf("Marshal(%T(%g)) = %q, must not match /%s/", vf, vf, out, re)
+ nfail++
+ return
+ }
+ }
+ }
+
+ var (
+ bigger = math.Inf(+1)
+ smaller = math.Inf(-1)
+ )
+
+ var digits = "1.2345678901234567890123"
+ for i := len(digits); i >= 2; i-- {
+ for exp := -30; exp <= 30; exp++ {
+ for _, sign := range "+-" {
+ for bits := 32; bits <= 64; bits += 32 {
+ s := fmt.Sprintf("%c%se%d", sign, digits[:i], exp)
+ f, err := strconv.ParseFloat(s, bits)
+ if err != nil {
+ log.Fatal(err)
+ }
+ next := math.Nextafter
+ if bits == 32 {
+ next = func(g, h float64) float64 {
+ return float64(math.Nextafter32(float32(g), float32(h)))
+ }
+ }
+ test(f, bits)
+ test(next(f, bigger), bits)
+ test(next(f, smaller), bits)
+ if nfail > 50 {
+ t.Fatalf("stopping test early")
+ }
+ }
+ }
+ }
+ }
+ test(0, 64)
+ test(math.Copysign(0, -1), 64)
+ test(0, 32)
+ test(math.Copysign(0, -1), 32)
+}