File: colorstring.go

package info (click to toggle)
golang-github-mitchellh-colorstring 0.0~git20150917.0.8631ce9-1.1
  • links: PTS, VCS
  • area: main
  • in suites: bookworm, bullseye, sid
  • size: 64 kB
  • sloc: makefile: 2
file content (244 lines) | stat: -rw-r--r-- 7,606 bytes parent folder | download | duplicates (2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
// colorstring provides functions for colorizing strings for terminal
// output.
package colorstring

import (
	"bytes"
	"fmt"
	"io"
	"regexp"
	"strings"
)

// Color colorizes your strings using the default settings.
//
// Strings given to Color should use the syntax `[color]` to specify the
// color for text following. For example: `[blue]Hello` will return "Hello"
// in blue. See DefaultColors for all the supported colors and attributes.
//
// If an unrecognized color is given, it is ignored and assumed to be part
// of the string. For example: `[hi]world` will result in "[hi]world".
//
// A color reset is appended to the end of every string. This will reset
// the color of following strings when you output this text to the same
// terminal session.
//
// If you want to customize any of this behavior, use the Colorize struct.
func Color(v string) string {
	return def.Color(v)
}

// ColorPrefix returns the color sequence that prefixes the given text.
//
// This is useful when wrapping text if you want to inherit the color
// of the wrapped text. For example, "[green]foo" will return "[green]".
// If there is no color sequence, then this will return "".
func ColorPrefix(v string) string {
	return def.ColorPrefix(v)
}

// Colorize colorizes your strings, giving you the ability to customize
// some of the colorization process.
//
// The options in Colorize can be set to customize colorization. If you're
// only interested in the defaults, just use the top Color function directly,
// which creates a default Colorize.
type Colorize struct {
	// Colors maps a color string to the code for that color. The code
	// is a string so that you can use more complex colors to set foreground,
	// background, attributes, etc. For example, "boldblue" might be
	// "1;34"
	Colors map[string]string

	// If true, color attributes will be ignored. This is useful if you're
	// outputting to a location that doesn't support colors and you just
	// want the strings returned.
	Disable bool

	// Reset, if true, will reset the color after each colorization by
	// adding a reset code at the end.
	Reset bool
}

// Color colorizes a string according to the settings setup in the struct.
//
// For more details on the syntax, see the top-level Color function.
func (c *Colorize) Color(v string) string {
	matches := parseRe.FindAllStringIndex(v, -1)
	if len(matches) == 0 {
		return v
	}

	result := new(bytes.Buffer)
	colored := false
	m := []int{0, 0}
	for _, nm := range matches {
		// Write the text in between this match and the last
		result.WriteString(v[m[1]:nm[0]])
		m = nm

		var replace string
		if code, ok := c.Colors[v[m[0]+1:m[1]-1]]; ok {
			colored = true

			if !c.Disable {
				replace = fmt.Sprintf("\033[%sm", code)
			}
		} else {
			replace = v[m[0]:m[1]]
		}

		result.WriteString(replace)
	}
	result.WriteString(v[m[1]:])

	if colored && c.Reset && !c.Disable {
		// Write the clear byte at the end
		result.WriteString("\033[0m")
	}

	return result.String()
}

// ColorPrefix returns the first color sequence that exists in this string.
//
// For example: "[green]foo" would return "[green]". If no color sequence
// exists, then "" is returned. This is especially useful when wrapping
// colored texts to inherit the color of the wrapped text.
func (c *Colorize) ColorPrefix(v string) string {
	return prefixRe.FindString(strings.TrimSpace(v))
}

// DefaultColors are the default colors used when colorizing.
//
// If the color is surrounded in underscores, such as "_blue_", then that
// color will be used for the background color.
var DefaultColors map[string]string

func init() {
	DefaultColors = map[string]string{
		// Default foreground/background colors
		"default":   "39",
		"_default_": "49",

		// Foreground colors
		"black":         "30",
		"red":           "31",
		"green":         "32",
		"yellow":        "33",
		"blue":          "34",
		"magenta":       "35",
		"cyan":          "36",
		"light_gray":    "37",
		"dark_gray":     "90",
		"light_red":     "91",
		"light_green":   "92",
		"light_yellow":  "93",
		"light_blue":    "94",
		"light_magenta": "95",
		"light_cyan":    "96",
		"white":         "97",

		// Background colors
		"_black_":         "40",
		"_red_":           "41",
		"_green_":         "42",
		"_yellow_":        "43",
		"_blue_":          "44",
		"_magenta_":       "45",
		"_cyan_":          "46",
		"_light_gray_":    "47",
		"_dark_gray_":     "100",
		"_light_red_":     "101",
		"_light_green_":   "102",
		"_light_yellow_":  "103",
		"_light_blue_":    "104",
		"_light_magenta_": "105",
		"_light_cyan_":    "106",
		"_white_":         "107",

		// Attributes
		"bold":       "1",
		"dim":        "2",
		"underline":  "4",
		"blink_slow": "5",
		"blink_fast": "6",
		"invert":     "7",
		"hidden":     "8",

		// Reset to reset everything to their defaults
		"reset":      "0",
		"reset_bold": "21",
	}

	def = Colorize{
		Colors: DefaultColors,
		Reset:  true,
	}
}

var def Colorize
var parseReRaw = `\[[a-z0-9_-]+\]`
var parseRe = regexp.MustCompile(`(?i)` + parseReRaw)
var prefixRe = regexp.MustCompile(`^(?i)(` + parseReRaw + `)+`)

// Print is a convenience wrapper for fmt.Print with support for color codes.
//
// Print formats using the default formats for its operands and writes to
// standard output with support for color codes. Spaces are added between
// operands when neither is a string. It returns the number of bytes written
// and any write error encountered.
func Print(a string) (n int, err error) {
	return fmt.Print(Color(a))
}

// Println is a convenience wrapper for fmt.Println with support for color
// codes.
//
// Println formats using the default formats for its operands and writes to
// standard output with support for color codes. Spaces are always added
// between operands and a newline is appended. It returns the number of bytes
// written and any write error encountered.
func Println(a string) (n int, err error) {
	return fmt.Println(Color(a))
}

// Printf is a convenience wrapper for fmt.Printf with support for color codes.
//
// Printf formats according to a format specifier and writes to standard output
// with support for color codes. It returns the number of bytes written and any
// write error encountered.
func Printf(format string, a ...interface{}) (n int, err error) {
	return fmt.Printf(Color(format), a...)
}

// Fprint is a convenience wrapper for fmt.Fprint with support for color codes.
//
// Fprint formats using the default formats for its operands and writes to w
// with support for color codes. Spaces are added between operands when neither
// is a string. It returns the number of bytes written and any write error
// encountered.
func Fprint(w io.Writer, a string) (n int, err error) {
	return fmt.Fprint(w, Color(a))
}

// Fprintln is a convenience wrapper for fmt.Fprintln with support for color
// codes.
//
// Fprintln formats using the default formats for its operands and writes to w
// with support for color codes. Spaces are always added between operands and a
// newline is appended. It returns the number of bytes written and any write
// error encountered.
func Fprintln(w io.Writer, a string) (n int, err error) {
	return fmt.Fprintln(w, Color(a))
}

// Fprintf is a convenience wrapper for fmt.Fprintf with support for color
// codes.
//
// Fprintf formats according to a format specifier and writes to w with support
// for color codes. It returns the number of bytes written and any write error
// encountered.
func Fprintf(w io.Writer, format string, a ...interface{}) (n int, err error) {
	return fmt.Fprintf(w, Color(format), a...)
}