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
|
var concatMap = require('concat-map');
var balanced = require('balanced-match');
module.exports = expandTop;
var escSlash = '\0SLASH'+Math.random()+'\0';
var escOpen = '\0OPEN'+Math.random()+'\0';
var escClose = '\0CLOSE'+Math.random()+'\0';
var escComma = '\0COMMA'+Math.random()+'\0';
var escPeriod = '\0PERIOD'+Math.random()+'\0';
function numeric(str) {
return parseInt(str, 10) == str
? parseInt(str, 10)
: str.charCodeAt(0);
}
function escapeBraces(str) {
return str.split('\\\\').join(escSlash)
.split('\\{').join(escOpen)
.split('\\}').join(escClose)
.split('\\,').join(escComma)
.split('\\.').join(escPeriod);
}
function unescapeBraces(str) {
return str.split(escSlash).join('\\')
.split(escOpen).join('{')
.split(escClose).join('}')
.split(escComma).join(',')
.split(escPeriod).join('.');
}
// Basically just str.split(","), but handling cases
// where we have nested braced sections, which should be
// treated as individual members, like {a,{b,c},d}
function parseCommaParts(str) {
if (!str)
return [''];
var parts = [];
var m = balanced('{', '}', str);
if (!m)
return str.split(',');
var pre = m.pre;
var body = m.body;
var post = m.post;
var p = pre.split(',');
p[p.length-1] += '{' + body + '}';
var postParts = parseCommaParts(post);
if (post.length) {
p[p.length-1] += postParts.shift();
p.push.apply(p, postParts);
}
parts.push.apply(parts, p);
return parts;
}
function expandTop(str) {
if (!str)
return [];
// I don't know why Bash 4.3 does this, but it does.
// Anything starting with {} will have the first two bytes preserved
// but *only* at the top level, so {},a}b will not expand to anything,
// but a{},b}c will be expanded to [a}c,abc].
// One could argue that this is a bug in Bash, but since the goal of
// this module is to match Bash's rules, we escape a leading {}
if (str.substr(0, 2) === '{}') {
str = '\\{\\}' + str.substr(2);
}
return expand(escapeBraces(str), true).map(unescapeBraces);
}
function identity(e) {
return e;
}
function embrace(str) {
return '{' + str + '}';
}
function isPadded(el) {
return /^-?0\d/.test(el);
}
function lte(i, y) {
return i <= y;
}
function gte(i, y) {
return i >= y;
}
function expand(str, isTop) {
var expansions = [];
var m = balanced('{', '}', str);
if (!m || /\$$/.test(m.pre)) return [str];
var isNumericSequence = /^-?\d+\.\.-?\d+(?:\.\.-?\d+)?$/.test(m.body);
var isAlphaSequence = /^[a-zA-Z]\.\.[a-zA-Z](?:\.\.-?\d+)?$/.test(m.body);
var isSequence = isNumericSequence || isAlphaSequence;
var isOptions = m.body.indexOf(',') >= 0;
if (!isSequence && !isOptions) {
// {a},b}
if (m.post.match(/,.*\}/)) {
str = m.pre + '{' + m.body + escClose + m.post;
return expand(str);
}
return [str];
}
var n;
if (isSequence) {
n = m.body.split(/\.\./);
} else {
n = parseCommaParts(m.body);
if (n.length === 1) {
// x{{a,b}}y ==> x{a}y x{b}y
n = expand(n[0], false).map(embrace);
if (n.length === 1) {
var post = m.post.length
? expand(m.post, false)
: [''];
return post.map(function(p) {
return m.pre + n[0] + p;
});
}
}
}
// at this point, n is the parts, and we know it's not a comma set
// with a single entry.
// no need to expand pre, since it is guaranteed to be free of brace-sets
var pre = m.pre;
var post = m.post.length
? expand(m.post, false)
: [''];
var N;
if (isSequence) {
var x = numeric(n[0]);
var y = numeric(n[1]);
var width = Math.max(n[0].length, n[1].length)
var incr = n.length == 3
? Math.abs(numeric(n[2]))
: 1;
var test = lte;
var reverse = y < x;
if (reverse) {
incr *= -1;
test = gte;
}
var pad = n.some(isPadded);
N = [];
for (var i = x; test(i, y); i += incr) {
var c;
if (isAlphaSequence) {
c = String.fromCharCode(i);
if (c === '\\')
c = '';
} else {
c = String(i);
if (pad) {
var need = width - c.length;
if (need > 0) {
var z = new Array(need + 1).join('0');
if (i < 0)
c = '-' + z + c.slice(1);
else
c = z + c;
}
}
}
N.push(c);
}
} else {
N = concatMap(n, function(el) { return expand(el, false) });
}
for (var j = 0; j < N.length; j++) {
for (var k = 0; k < post.length; k++) {
var expansion = pre + N[j] + post[k];
if (!isTop || isSequence || expansion)
expansions.push(expansion);
}
}
return expansions;
}
|
