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Issue 1400473008: Roll Observatory packages and add a roll script (Closed) Base URL: git@github.com:dart-lang/observatory_pub_packages.git@master
Patch Set: Created 5 years, 2 months ago
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1 // Copyright (c) 2013, the Dart project authors. Please see the AUTHORS file
2 // for details. All rights reserved. Use of this source code is governed by a
3 // BSD-style license that can be found in the LICENSE file.
4
5 library path.context;
6
7 import 'internal_style.dart';
8 import 'style.dart';
9 import 'parsed_path.dart';
10 import 'path_exception.dart';
11 import '../path.dart' as p;
12
13 Context createInternal() => new Context._internal();
14
15 /// An instantiable class for manipulating paths. Unlike the top-level
16 /// functions, this lets you explicitly select what platform the paths will use.
17 class Context {
18 /// Creates a new path context for the given style and current directory.
19 ///
20 /// If [style] is omitted, it uses the host operating system's path style. If
21 /// only [current] is omitted, it defaults ".". If *both* [style] and
22 /// [current] are omitted, [current] defaults to the real current working
23 /// directory.
24 ///
25 /// On the browser, [style] defaults to [Style.url] and [current] defaults to
26 /// the current URL.
27 factory Context({Style style, String current}) {
28 if (current == null) {
29 if (style == null) {
30 current = p.current;
31 } else {
32 current = ".";
33 }
34 }
35
36 if (style == null) {
37 style = Style.platform;
38 } else if (style is! InternalStyle) {
39 throw new ArgumentError("Only styles defined by the path package are "
40 "allowed.");
41 }
42
43 return new Context._(style as InternalStyle, current);
44 }
45
46 /// Create a [Context] to be used internally within path.
47 Context._internal()
48 : style = Style.platform as InternalStyle,
49 _current = null;
50
51 Context._(this.style, this._current);
52
53 /// The style of path that this context works with.
54 final InternalStyle style;
55
56 /// The current directory given when Context was created. If null, current
57 /// directory is evaluated from 'p.current'.
58 final String _current;
59
60 /// The current directory that relative paths are relative to.
61 String get current => _current != null ? _current : p.current;
62
63 /// Gets the path separator for the context's [style]. On Mac and Linux,
64 /// this is `/`. On Windows, it's `\`.
65 String get separator => style.separator;
66
67 /// Creates a new path by appending the given path parts to [current].
68 /// Equivalent to [join()] with [current] as the first argument. Example:
69 ///
70 /// var context = new Context(current: '/root');
71 /// context.absolute('path', 'to', 'foo'); // -> '/root/path/to/foo'
72 ///
73 /// If [current] isn't absolute, this won't return an absolute path.
74 String absolute(String part1, [String part2, String part3, String part4,
75 String part5, String part6, String part7]) {
76 return join(current, part1, part2, part3, part4, part5, part6, part7);
77 }
78
79 /// Gets the part of [path] after the last separator on the context's
80 /// platform.
81 ///
82 /// context.basename('path/to/foo.dart'); // -> 'foo.dart'
83 /// context.basename('path/to'); // -> 'to'
84 ///
85 /// Trailing separators are ignored.
86 ///
87 /// context.basename('path/to/'); // -> 'to'
88 String basename(String path) => _parse(path).basename;
89
90 /// Gets the part of [path] after the last separator on the context's
91 /// platform, and without any trailing file extension.
92 ///
93 /// context.basenameWithoutExtension('path/to/foo.dart'); // -> 'foo'
94 ///
95 /// Trailing separators are ignored.
96 ///
97 /// context.basenameWithoutExtension('path/to/foo.dart/'); // -> 'foo'
98 String basenameWithoutExtension(String path) =>
99 _parse(path).basenameWithoutExtension;
100
101 /// Gets the part of [path] before the last separator.
102 ///
103 /// context.dirname('path/to/foo.dart'); // -> 'path/to'
104 /// context.dirname('path/to'); // -> 'path'
105 ///
106 /// Trailing separators are ignored.
107 ///
108 /// context.dirname('path/to/'); // -> 'path'
109 String dirname(String path) {
110 var parsed = _parse(path);
111 parsed.removeTrailingSeparators();
112 if (parsed.parts.isEmpty) return parsed.root == null ? '.' : parsed.root;
113 if (parsed.parts.length == 1) {
114 return parsed.root == null ? '.' : parsed.root;
115 }
116 parsed.parts.removeLast();
117 parsed.separators.removeLast();
118 parsed.removeTrailingSeparators();
119 return parsed.toString();
120 }
121
122 /// Gets the file extension of [path]: the portion of [basename] from the last
123 /// `.` to the end (including the `.` itself).
124 ///
125 /// context.extension('path/to/foo.dart'); // -> '.dart'
126 /// context.extension('path/to/foo'); // -> ''
127 /// context.extension('path.to/foo'); // -> ''
128 /// context.extension('path/to/foo.dart.js'); // -> '.js'
129 ///
130 /// If the file name starts with a `.`, then it is not considered an
131 /// extension:
132 ///
133 /// context.extension('~/.bashrc'); // -> ''
134 /// context.extension('~/.notes.txt'); // -> '.txt'
135 String extension(String path) => _parse(path).extension;
136
137 // TODO(nweiz): add a UNC example for Windows once issue 7323 is fixed.
138 /// Returns the root of [path] if it's absolute, or an empty string if it's
139 /// relative.
140 ///
141 /// // Unix
142 /// context.rootPrefix('path/to/foo'); // -> ''
143 /// context.rootPrefix('/path/to/foo'); // -> '/'
144 ///
145 /// // Windows
146 /// context.rootPrefix(r'path\to\foo'); // -> ''
147 /// context.rootPrefix(r'C:\path\to\foo'); // -> r'C:\'
148 ///
149 /// // URL
150 /// context.rootPrefix('path/to/foo'); // -> ''
151 /// context.rootPrefix('http://dartlang.org/path/to/foo');
152 /// // -> 'http://dartlang.org'
153 String rootPrefix(String path) => path.substring(0, style.rootLength(path));
154
155 /// Returns `true` if [path] is an absolute path and `false` if it is a
156 /// relative path.
157 ///
158 /// On POSIX systems, absolute paths start with a `/` (forward slash). On
159 /// Windows, an absolute path starts with `\\`, or a drive letter followed by
160 /// `:/` or `:\`. For URLs, absolute paths either start with a protocol and
161 /// optional hostname (e.g. `http://dartlang.org`, `file://`) or with a `/`.
162 ///
163 /// URLs that start with `/` are known as "root-relative", since they're
164 /// relative to the root of the current URL. Since root-relative paths are
165 /// still absolute in every other sense, [isAbsolute] will return true for
166 /// them. They can be detected using [isRootRelative].
167 bool isAbsolute(String path) => style.rootLength(path) > 0;
168
169 /// Returns `true` if [path] is a relative path and `false` if it is absolute.
170 /// On POSIX systems, absolute paths start with a `/` (forward slash). On
171 /// Windows, an absolute path starts with `\\`, or a drive letter followed by
172 /// `:/` or `:\`.
173 bool isRelative(String path) => !this.isAbsolute(path);
174
175 /// Returns `true` if [path] is a root-relative path and `false` if it's not.
176 ///
177 /// URLs that start with `/` are known as "root-relative", since they're
178 /// relative to the root of the current URL. Since root-relative paths are
179 /// still absolute in every other sense, [isAbsolute] will return true for
180 /// them. They can be detected using [isRootRelative].
181 ///
182 /// No POSIX and Windows paths are root-relative.
183 bool isRootRelative(String path) => style.isRootRelative(path);
184
185 /// Joins the given path parts into a single path. Example:
186 ///
187 /// context.join('path', 'to', 'foo'); // -> 'path/to/foo'
188 ///
189 /// If any part ends in a path separator, then a redundant separator will not
190 /// be added:
191 ///
192 /// context.join('path/', 'to', 'foo'); // -> 'path/to/foo
193 ///
194 /// If a part is an absolute path, then anything before that will be ignored:
195 ///
196 /// context.join('path', '/to', 'foo'); // -> '/to/foo'
197 ///
198 String join(String part1, [String part2, String part3, String part4,
199 String part5, String part6, String part7, String part8]) {
200 var parts = <String>[
201 part1,
202 part2,
203 part3,
204 part4,
205 part5,
206 part6,
207 part7,
208 part8
209 ];
210 _validateArgList("join", parts);
211 return joinAll(parts.where((part) => part != null));
212 }
213
214 /// Joins the given path parts into a single path. Example:
215 ///
216 /// context.joinAll(['path', 'to', 'foo']); // -> 'path/to/foo'
217 ///
218 /// If any part ends in a path separator, then a redundant separator will not
219 /// be added:
220 ///
221 /// context.joinAll(['path/', 'to', 'foo']); // -> 'path/to/foo
222 ///
223 /// If a part is an absolute path, then anything before that will be ignored:
224 ///
225 /// context.joinAll(['path', '/to', 'foo']); // -> '/to/foo'
226 ///
227 /// For a fixed number of parts, [join] is usually terser.
228 String joinAll(Iterable<String> parts) {
229 var buffer = new StringBuffer();
230 var needsSeparator = false;
231 var isAbsoluteAndNotRootRelative = false;
232
233 for (var part in parts.where((part) => part != '')) {
234 if (this.isRootRelative(part) && isAbsoluteAndNotRootRelative) {
235 // If the new part is root-relative, it preserves the previous root but
236 // replaces the path after it.
237 var parsed = _parse(part);
238 parsed.root = this.rootPrefix(buffer.toString());
239 if (style.needsSeparator(parsed.root)) {
240 parsed.separators[0] = style.separator;
241 }
242 buffer.clear();
243 buffer.write(parsed.toString());
244 } else if (this.isAbsolute(part)) {
245 isAbsoluteAndNotRootRelative = !this.isRootRelative(part);
246 // An absolute path discards everything before it.
247 buffer.clear();
248 buffer.write(part);
249 } else {
250 if (part.length > 0 && style.containsSeparator(part[0])) {
251 // The part starts with a separator, so we don't need to add one.
252 } else if (needsSeparator) {
253 buffer.write(separator);
254 }
255
256 buffer.write(part);
257 }
258
259 // Unless this part ends with a separator, we'll need to add one before
260 // the next part.
261 needsSeparator = style.needsSeparator(part);
262 }
263
264 return buffer.toString();
265 }
266
267 // TODO(nweiz): add a UNC example for Windows once issue 7323 is fixed.
268 /// Splits [path] into its components using the current platform's
269 /// [separator]. Example:
270 ///
271 /// context.split('path/to/foo'); // -> ['path', 'to', 'foo']
272 ///
273 /// The path will *not* be normalized before splitting.
274 ///
275 /// context.split('path/../foo'); // -> ['path', '..', 'foo']
276 ///
277 /// If [path] is absolute, the root directory will be the first element in the
278 /// array. Example:
279 ///
280 /// // Unix
281 /// context.split('/path/to/foo'); // -> ['/', 'path', 'to', 'foo']
282 ///
283 /// // Windows
284 /// context.split(r'C:\path\to\foo'); // -> [r'C:\', 'path', 'to', 'foo']
285 List<String> split(String path) {
286 var parsed = _parse(path);
287 // Filter out empty parts that exist due to multiple separators in a row.
288 parsed.parts = parsed.parts.where((part) => !part.isEmpty).toList();
289 if (parsed.root != null) parsed.parts.insert(0, parsed.root);
290 return parsed.parts;
291 }
292
293 /// Normalizes [path], simplifying it by handling `..`, and `.`, and
294 /// removing redundant path separators whenever possible.
295 ///
296 /// context.normalize('path/./to/..//file.text'); // -> 'path/file.txt'
297 String normalize(String path) {
298 var parsed = _parse(path);
299 parsed.normalize();
300 return parsed.toString();
301 }
302
303 /// Attempts to convert [path] to an equivalent relative path relative to
304 /// [root].
305 ///
306 /// var context = new Context(current: '/root/path');
307 /// context.relative('/root/path/a/b.dart'); // -> 'a/b.dart'
308 /// context.relative('/root/other.dart'); // -> '../other.dart'
309 ///
310 /// If the [from] argument is passed, [path] is made relative to that instead.
311 ///
312 /// context.relative('/root/path/a/b.dart',
313 /// from: '/root/path'); // -> 'a/b.dart'
314 /// context.relative('/root/other.dart',
315 /// from: '/root/path'); // -> '../other.dart'
316 ///
317 /// If [path] and/or [from] are relative paths, they are assumed to be
318 /// relative to [current].
319 ///
320 /// Since there is no relative path from one drive letter to another on
321 /// Windows, this will return an absolute path in that case.
322 ///
323 /// context.relative(r'D:\other', from: r'C:\other'); // -> 'D:\other'
324 ///
325 /// This will also return an absolute path if an absolute [path] is passed to
326 /// a context with a relative path for [current].
327 ///
328 /// var context = new Context(r'some/relative/path');
329 /// context.relative(r'/absolute/path'); // -> '/absolute/path'
330 ///
331 /// If [root] is relative, it may be impossible to determine a path from
332 /// [from] to [path]. For example, if [root] and [path] are "." and [from] is
333 /// "/", no path can be determined. In this case, a [PathException] will be
334 /// thrown.
335 String relative(String path, {String from}) {
336 // Avoid calling [current] since it is slow and calling join() when
337 // [from] is absolute does nothing.
338 if (from == null) {
339 from = current;
340 } else if (this.isRelative(from) || this.isRootRelative(from)) {
341 from = this.join(current, from);
342 }
343
344 // We can't determine the path from a relative path to an absolute path.
345 if (this.isRelative(from) && this.isAbsolute(path)) {
346 return this.normalize(path);
347 }
348
349 // If the given path is relative, resolve it relative to the context's
350 // current directory.
351 if (this.isRelative(path) || this.isRootRelative(path)) {
352 path = this.absolute(path);
353 }
354
355 // If the path is still relative and `from` is absolute, we're unable to
356 // find a path from `from` to `path`.
357 if (this.isRelative(path) && this.isAbsolute(from)) {
358 throw new PathException('Unable to find a path to "$path" from "$from".');
359 }
360
361 var fromParsed = _parse(from)..normalize();
362 var pathParsed = _parse(path)..normalize();
363
364 if (fromParsed.parts.length > 0 && fromParsed.parts[0] == '.') {
365 return pathParsed.toString();
366 }
367
368 // If the root prefixes don't match (for example, different drive letters
369 // on Windows), then there is no relative path, so just return the absolute
370 // one. In Windows, drive letters are case-insenstive and we allow
371 // calculation of relative paths, even if a path has not been normalized.
372 if (fromParsed.root != pathParsed.root &&
373 ((fromParsed.root == null || pathParsed.root == null) ||
374 fromParsed.root.toLowerCase().replaceAll('/', '\\') !=
375 pathParsed.root.toLowerCase().replaceAll('/', '\\'))) {
376 return pathParsed.toString();
377 }
378
379 // Strip off their common prefix.
380 while (fromParsed.parts.length > 0 &&
381 pathParsed.parts.length > 0 &&
382 fromParsed.parts[0] == pathParsed.parts[0]) {
383 fromParsed.parts.removeAt(0);
384 fromParsed.separators.removeAt(1);
385 pathParsed.parts.removeAt(0);
386 pathParsed.separators.removeAt(1);
387 }
388
389 // If there are any directories left in the from path, we need to walk up
390 // out of them. If a directory left in the from path is '..', it cannot
391 // be cancelled by adding a '..'.
392 if (fromParsed.parts.length > 0 && fromParsed.parts[0] == '..') {
393 throw new PathException('Unable to find a path to "$path" from "$from".');
394 }
395 pathParsed.parts.insertAll(
396 0, new List.filled(fromParsed.parts.length, '..'));
397 pathParsed.separators[0] = '';
398 pathParsed.separators.insertAll(
399 1, new List.filled(fromParsed.parts.length, style.separator));
400
401 // Corner case: the paths completely collapsed.
402 if (pathParsed.parts.length == 0) return '.';
403
404 // Corner case: path was '.' and some '..' directories were added in front.
405 // Don't add a final '/.' in that case.
406 if (pathParsed.parts.length > 1 && pathParsed.parts.last == '.') {
407 pathParsed.parts.removeLast();
408 pathParsed.separators
409 ..removeLast()
410 ..removeLast()
411 ..add('');
412 }
413
414 // Make it relative.
415 pathParsed.root = '';
416 pathParsed.removeTrailingSeparators();
417
418 return pathParsed.toString();
419 }
420
421 /// Returns `true` if [child] is a path beneath `parent`, and `false`
422 /// otherwise.
423 ///
424 /// path.isWithin('/root/path', '/root/path/a'); // -> true
425 /// path.isWithin('/root/path', '/root/other'); // -> false
426 /// path.isWithin('/root/path', '/root/path'); // -> false
427 bool isWithin(String parent, String child) {
428 var relative;
429 try {
430 relative = this.relative(child, from: parent);
431 } on PathException catch (_) {
432 // If no relative path from [parent] to [child] is found, [child]
433 // definitely isn't a child of [parent].
434 return false;
435 }
436
437 var parts = this.split(relative);
438 return this.isRelative(relative) &&
439 parts.first != '..' &&
440 parts.first != '.';
441 }
442
443 /// Removes a trailing extension from the last part of [path].
444 ///
445 /// context.withoutExtension('path/to/foo.dart'); // -> 'path/to/foo'
446 String withoutExtension(String path) {
447 var parsed = _parse(path);
448
449 for (var i = parsed.parts.length - 1; i >= 0; i--) {
450 if (!parsed.parts[i].isEmpty) {
451 parsed.parts[i] = parsed.basenameWithoutExtension;
452 break;
453 }
454 }
455
456 return parsed.toString();
457 }
458
459 /// Returns the path represented by [uri], which may be a [String] or a [Uri].
460 ///
461 /// For POSIX and Windows styles, [uri] must be a `file:` URI. For the URL
462 /// style, this will just convert [uri] to a string.
463 ///
464 /// // POSIX
465 /// context.fromUri('file:///path/to/foo')
466 /// // -> '/path/to/foo'
467 ///
468 /// // Windows
469 /// context.fromUri('file:///C:/path/to/foo')
470 /// // -> r'C:\path\to\foo'
471 ///
472 /// // URL
473 /// context.fromUri('http://dartlang.org/path/to/foo')
474 /// // -> 'http://dartlang.org/path/to/foo'
475 ///
476 /// If [uri] is relative, a relative path will be returned.
477 ///
478 /// path.fromUri('path/to/foo'); // -> 'path/to/foo'
479 String fromUri(uri) {
480 if (uri is String) uri = Uri.parse(uri);
481 return style.pathFromUri(uri);
482 }
483
484 /// Returns the URI that represents [path].
485 ///
486 /// For POSIX and Windows styles, this will return a `file:` URI. For the URL
487 /// style, this will just convert [path] to a [Uri].
488 ///
489 /// // POSIX
490 /// context.toUri('/path/to/foo')
491 /// // -> Uri.parse('file:///path/to/foo')
492 ///
493 /// // Windows
494 /// context.toUri(r'C:\path\to\foo')
495 /// // -> Uri.parse('file:///C:/path/to/foo')
496 ///
497 /// // URL
498 /// context.toUri('http://dartlang.org/path/to/foo')
499 /// // -> Uri.parse('http://dartlang.org/path/to/foo')
500 Uri toUri(String path) {
501 if (isRelative(path)) {
502 return style.relativePathToUri(path);
503 } else {
504 return style.absolutePathToUri(join(current, path));
505 }
506 }
507
508 /// Returns a terse, human-readable representation of [uri].
509 ///
510 /// [uri] can be a [String] or a [Uri]. If it can be made relative to the
511 /// current working directory, that's done. Otherwise, it's returned as-is.
512 /// This gracefully handles non-`file:` URIs for [Style.posix] and
513 /// [Style.windows].
514 ///
515 /// The returned value is meant for human consumption, and may be either URI-
516 /// or path-formatted.
517 ///
518 /// // POSIX
519 /// var context = new Context(current: '/root/path');
520 /// context.prettyUri('file:///root/path/a/b.dart'); // -> 'a/b.dart'
521 /// context.prettyUri('http://dartlang.org/'); // -> 'http://dartlang.org'
522 ///
523 /// // Windows
524 /// var context = new Context(current: r'C:\root\path');
525 /// context.prettyUri('file:///C:/root/path/a/b.dart'); // -> r'a\b.dart'
526 /// context.prettyUri('http://dartlang.org/'); // -> 'http://dartlang.org'
527 ///
528 /// // URL
529 /// var context = new Context(current: 'http://dartlang.org/root/path');
530 /// context.prettyUri('http://dartlang.org/root/path/a/b.dart');
531 /// // -> r'a/b.dart'
532 /// context.prettyUri('file:///root/path'); // -> 'file:///root/path'
533 String prettyUri(uri) {
534 if (uri is String) uri = Uri.parse(uri);
535 if (uri.scheme == 'file' && style == Style.url) return uri.toString();
536 if (uri.scheme != 'file' && uri.scheme != '' && style != Style.url) {
537 return uri.toString();
538 }
539
540 var path = normalize(fromUri(uri));
541 var rel = relative(path);
542
543 // Only return a relative path if it's actually shorter than the absolute
544 // path. This avoids ugly things like long "../" chains to get to the root
545 // and then go back down.
546 return split(rel).length > split(path).length ? path : rel;
547 }
548
549 ParsedPath _parse(String path) => new ParsedPath.parse(path, style);
550 }
551
552 /// Validates that there are no non-null arguments following a null one and
553 /// throws an appropriate [ArgumentError] on failure.
554 _validateArgList(String method, List<String> args) {
555 for (var i = 1; i < args.length; i++) {
556 // Ignore nulls hanging off the end.
557 if (args[i] == null || args[i - 1] != null) continue;
558
559 var numArgs;
560 for (numArgs = args.length; numArgs >= 1; numArgs--) {
561 if (args[numArgs - 1] != null) break;
562 }
563
564 // Show the arguments.
565 var message = new StringBuffer();
566 message.write("$method(");
567 message.write(args
568 .take(numArgs)
569 .map((arg) => arg == null ? "null" : '"$arg"')
570 .join(", "));
571 message.write("): part ${i - 1} was null, but part $i was not.");
572 throw new ArgumentError(message.toString());
573 }
574 }
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