mirror of https://github.com/docker/cli.git
142 lines
3.4 KiB
Go
142 lines
3.4 KiB
Go
// Copyright 2010 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 "bytes"
|
|
|
|
// Compact appends to dst the JSON-encoded src with
|
|
// insignificant space characters elided.
|
|
func Compact(dst *bytes.Buffer, src []byte) error {
|
|
return compact(dst, src, false)
|
|
}
|
|
|
|
func compact(dst *bytes.Buffer, src []byte, escape bool) error {
|
|
origLen := dst.Len()
|
|
var scan scanner
|
|
scan.reset()
|
|
start := 0
|
|
for i, c := range src {
|
|
if escape && (c == '<' || c == '>' || c == '&') {
|
|
if start < i {
|
|
dst.Write(src[start:i])
|
|
}
|
|
dst.WriteString(`\u00`)
|
|
dst.WriteByte(hex[c>>4])
|
|
dst.WriteByte(hex[c&0xF])
|
|
start = i + 1
|
|
}
|
|
// Convert U+2028 and U+2029 (E2 80 A8 and E2 80 A9).
|
|
if c == 0xE2 && i+2 < len(src) && src[i+1] == 0x80 && src[i+2]&^1 == 0xA8 {
|
|
if start < i {
|
|
dst.Write(src[start:i])
|
|
}
|
|
dst.WriteString(`\u202`)
|
|
dst.WriteByte(hex[src[i+2]&0xF])
|
|
start = i + 3
|
|
}
|
|
v := scan.step(&scan, c)
|
|
if v >= scanSkipSpace {
|
|
if v == scanError {
|
|
break
|
|
}
|
|
if start < i {
|
|
dst.Write(src[start:i])
|
|
}
|
|
start = i + 1
|
|
}
|
|
}
|
|
if scan.eof() == scanError {
|
|
dst.Truncate(origLen)
|
|
return scan.err
|
|
}
|
|
if start < len(src) {
|
|
dst.Write(src[start:])
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func newline(dst *bytes.Buffer, prefix, indent string, depth int) {
|
|
dst.WriteByte('\n')
|
|
dst.WriteString(prefix)
|
|
for i := 0; i < depth; i++ {
|
|
dst.WriteString(indent)
|
|
}
|
|
}
|
|
|
|
// Indent appends to dst an indented form of the JSON-encoded src.
|
|
// Each element in a JSON object or array begins on a new,
|
|
// indented line beginning with prefix followed by one or more
|
|
// copies of indent according to the indentation nesting.
|
|
// The data appended to dst does not begin with the prefix nor
|
|
// any indentation, to make it easier to embed inside other formatted JSON data.
|
|
// Although leading space characters (space, tab, carriage return, newline)
|
|
// at the beginning of src are dropped, trailing space characters
|
|
// at the end of src are preserved and copied to dst.
|
|
// For example, if src has no trailing spaces, neither will dst;
|
|
// if src ends in a trailing newline, so will dst.
|
|
func Indent(dst *bytes.Buffer, src []byte, prefix, indent string) error {
|
|
origLen := dst.Len()
|
|
var scan scanner
|
|
scan.reset()
|
|
needIndent := false
|
|
depth := 0
|
|
for _, c := range src {
|
|
scan.bytes++
|
|
v := scan.step(&scan, c)
|
|
if v == scanSkipSpace {
|
|
continue
|
|
}
|
|
if v == scanError {
|
|
break
|
|
}
|
|
if needIndent && v != scanEndObject && v != scanEndArray {
|
|
needIndent = false
|
|
depth++
|
|
newline(dst, prefix, indent, depth)
|
|
}
|
|
|
|
// Emit semantically uninteresting bytes
|
|
// (in particular, punctuation in strings) unmodified.
|
|
if v == scanContinue {
|
|
dst.WriteByte(c)
|
|
continue
|
|
}
|
|
|
|
// Add spacing around real punctuation.
|
|
switch c {
|
|
case '{', '[':
|
|
// delay indent so that empty object and array are formatted as {} and [].
|
|
needIndent = true
|
|
dst.WriteByte(c)
|
|
|
|
case ',':
|
|
dst.WriteByte(c)
|
|
newline(dst, prefix, indent, depth)
|
|
|
|
case ':':
|
|
dst.WriteByte(c)
|
|
dst.WriteByte(' ')
|
|
|
|
case '}', ']':
|
|
if needIndent {
|
|
// suppress indent in empty object/array
|
|
needIndent = false
|
|
} else {
|
|
depth--
|
|
newline(dst, prefix, indent, depth)
|
|
}
|
|
dst.WriteByte(c)
|
|
|
|
default:
|
|
dst.WriteByte(c)
|
|
}
|
|
}
|
|
if scan.eof() == scanError {
|
|
dst.Truncate(origLen)
|
|
return scan.err
|
|
}
|
|
return nil
|
|
}
|