internal/encoding/jsonx: copy internal/encoding/json
We're rewriting internal/encoding/json. So, make a copy of it first in
order not to break encoding/jsonpb package.
Change-Id: I8b63c468d3f432102d2af4db22a7549998ce3876
Reviewed-on: https://go-review.googlesource.com/c/164642
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
diff --git a/internal/encoding/jsonx/number.go b/internal/encoding/jsonx/number.go
new file mode 100644
index 0000000..ec99cbd
--- /dev/null
+++ b/internal/encoding/jsonx/number.go
@@ -0,0 +1,79 @@
+// Copyright 2018 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 json
+
+import (
+ "io"
+ "math"
+ "regexp"
+ "strconv"
+
+ "github.com/golang/protobuf/v2/internal/errors"
+)
+
+// marshalNumber encodes v as a Number.
+func (p *encoder) marshalNumber(v Value) error {
+ var err error
+ p.out, err = appendNumber(p.out, v)
+ return err
+}
+func appendNumber(out []byte, v Value) ([]byte, error) {
+ if v.Type() != Number {
+ return nil, errors.New("invalid type %v, expected number", v.Type())
+ }
+ if len(v.raw) > 0 {
+ return append(out, v.raw...), nil
+ }
+ n := v.Number()
+ if math.IsInf(n, 0) || math.IsNaN(n) {
+ return nil, errors.New("invalid number value: %v", n)
+ }
+
+ // JSON number formatting logic based on encoding/json.
+ // See floatEncoder.encode for reference.
+ bits := 64
+ if float64(float32(n)) == n {
+ bits = 32
+ }
+ fmt := byte('f')
+ if abs := math.Abs(n); abs != 0 {
+ if bits == 64 && (abs < 1e-6 || abs >= 1e21) || bits == 32 && (float32(abs) < 1e-6 || float32(abs) >= 1e21) {
+ fmt = 'e'
+ }
+ }
+ out = strconv.AppendFloat(out, n, fmt, -1, bits)
+ if fmt == 'e' {
+ n := len(out)
+ if n >= 4 && out[n-4] == 'e' && out[n-3] == '-' && out[n-2] == '0' {
+ out[n-2] = out[n-1]
+ out = out[:n-1]
+ }
+ }
+ return out, nil
+}
+
+// Exact expression to match a JSON floating-point number.
+// JSON's grammar for floats is more restrictive than Go's grammar.
+var floatRegexp = regexp.MustCompile("^-?(0|[1-9][0-9]*)([.][0-9]+)?([eE][+-]?[0-9]+)?")
+
+// unmarshalNumber decodes a Number from the input.
+func (p *decoder) unmarshalNumber() (Value, error) {
+ v, n, err := consumeNumber(p.in)
+ p.consume(n)
+ return v, err
+}
+func consumeNumber(in []byte) (Value, int, error) {
+ if len(in) == 0 {
+ return Value{}, 0, io.ErrUnexpectedEOF
+ }
+ if n := matchWithDelim(floatRegexp, in); n > 0 {
+ v, err := strconv.ParseFloat(string(in[:n]), 64)
+ if err != nil {
+ return Value{}, 0, err
+ }
+ return rawValueOf(v, in[:n:n]), n, nil
+ }
+ return Value{}, 0, newSyntaxError("invalid %q as number", errRegexp.Find(in))
+}