1 # Copyright 2015 The Rust Project Developers. See the COPYRIGHT
2 # file at the top-level directory of this distribution and at
3 # http://rust-lang.org/COPYRIGHT.
5 # Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 # http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 # <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 # option. This file may not be copied, modified, or distributed
9 # except according to those terms.
12 htmldocck.py is a custom checker script for Rustdoc HTML outputs.
16 The principle is simple: This script receives a path to generated HTML
17 documentation and a "template" script, which has a series of check
18 commands like `@has` or `@matches`. Each command can be used to check if
19 some pattern is present or not present in the particular file or in
20 the particular node of HTML tree. In many cases, the template script
21 happens to be a source code given to rustdoc.
23 While it indeed is possible to test in smaller portions, it has been
24 hard to construct tests in this fashion and major rendering errors were
25 discovered much later. This script is designed for making the black-box
26 and regression testing of Rustdoc easy. This does not preclude the needs
27 for unit testing, but can be used to complement related tests by quickly
28 showing the expected renderings.
30 In order to avoid one-off dependencies for this task, this script uses
31 a reasonably working HTML parser and the existing XPath implementation
32 from Python 2's standard library. Hopefully we won't render
37 Commands start with an `@` followed by a command name (letters and
38 hyphens), and zero or more arguments separated by one or more whitespace
39 and optionally delimited with single or double quotes. The `@` mark
40 cannot be preceded by a non-whitespace character. Other lines (including
41 every text up to the first `@`) are ignored, but it is recommended to
42 avoid the use of `@` in the template file.
44 There are a number of supported commands:
46 * `@has PATH` checks for the existence of given file.
48 `PATH` is relative to the output directory. It can be given as `-`
49 which repeats the most recently used `PATH`.
51 * `@has PATH PATTERN` and `@matches PATH PATTERN` checks for
52 the occurrence of given `PATTERN` in the given file. Only one
53 occurrence of given pattern is enough.
55 For `@has`, `PATTERN` is a whitespace-normalized (every consecutive
56 whitespace being replaced by one single space character) string.
57 The entire file is also whitespace-normalized including newlines.
59 For `@matches`, `PATTERN` is a Python-supported regular expression.
60 The file remains intact but the regexp is matched with no `MULTILINE`
61 and `IGNORECASE` option. You can still use a prefix `(?m)` or `(?i)`
62 to override them, and `\A` and `\Z` for definitely matching
63 the beginning and end of the file.
65 (The same distinction goes to other variants of these commands.)
67 * `@has PATH XPATH PATTERN` and `@matches PATH XPATH PATTERN` checks for
68 the presence of given `XPATH` in the given HTML file, and also
69 the occurrence of given `PATTERN` in the matching node or attribute.
70 Only one occurrence of given pattern in the match is enough.
72 `PATH` should be a valid and well-formed HTML file. It does *not*
73 accept arbitrary HTML5; it should have matching open and close tags
74 and correct entity references at least.
76 `XPATH` is an XPath expression to match. This is fairly limited:
77 `tag`, `*`, `.`, `//`, `..`, `[@attr]`, `[@attr='value']`, `[tag]`,
78 `[POS]` (element located in given `POS`), `[last()-POS]`, `text()`
79 and `@attr` (both as the last segment) are supported. Some examples:
81 - `//pre` or `.//pre` matches any element with a name `pre`.
82 - `//a[@href]` matches any element with an `href` attribute.
83 - `//*[@class="impl"]//code` matches any element with a name `code`,
84 which is an ancestor of some element which `class` attr is `impl`.
85 - `//h1[@class="fqn"]/span[1]/a[last()]/@class` matches a value of
86 `class` attribute in the last `a` element (can be followed by more
87 elements that are not `a`) inside the first `span` in the `h1` with
88 a class of `fqn`. Note that there cannot be no additional elements
89 between them due to the use of `/` instead of `//`.
91 Do not try to use non-absolute paths, it won't work due to the flawed
92 ElementTree implementation. The script rejects them.
94 For the text matches (i.e. paths not ending with `@attr`), any
95 subelements are flattened into one string; this is handy for ignoring
96 highlights for example. If you want to simply check the presence of
97 given node or attribute, use an empty string (`""`) as a `PATTERN`.
99 All conditions can be negated with `!`. `@!has foo/type.NoSuch.html`
100 checks if the given file does not exist, for example.
108 from collections import namedtuple
109 from HTMLParser import HTMLParser
110 from xml.etree import cElementTree as ET
112 # ⇤/⇥ are not in HTML 4 but are in HTML 5
113 from htmlentitydefs import entitydefs
114 entitydefs['larrb'] = u'\u21e4'
115 entitydefs['rarrb'] = u'\u21e5'
117 # "void elements" (no closing tag) from the HTML Standard section 12.1.2
118 VOID_ELEMENTS = set(['area', 'base', 'br', 'col', 'embed', 'hr', 'img', 'input', 'keygen',
119 'link', 'menuitem', 'meta', 'param', 'source', 'track', 'wbr'])
121 # simplified HTML parser.
122 # this is possible because we are dealing with very regular HTML from rustdoc;
123 # we only have to deal with i) void elements and ii) empty attributes.
124 class CustomHTMLParser(HTMLParser):
125 def __init__(self, target=None):
126 HTMLParser.__init__(self)
127 self.__builder = target or ET.TreeBuilder()
128 def handle_starttag(self, tag, attrs):
129 attrs = dict((k, v or '') for k, v in attrs)
130 self.__builder.start(tag, attrs)
131 if tag in VOID_ELEMENTS: self.__builder.end(tag)
132 def handle_endtag(self, tag):
133 self.__builder.end(tag)
134 def handle_startendtag(self, tag, attrs):
135 attrs = dict((k, v or '') for k, v in attrs)
136 self.__builder.start(tag, attrs)
137 self.__builder.end(tag)
138 def handle_data(self, data):
139 self.__builder.data(data)
140 def handle_entityref(self, name):
141 self.__builder.data(entitydefs[name])
142 def handle_charref(self, name):
143 code = int(name[1:], 16) if name.startswith(('x', 'X')) else int(name, 10)
144 self.__builder.data(unichr(code).encode('utf-8'))
146 HTMLParser.close(self)
147 return self.__builder.close()
149 Command = namedtuple('Command', 'negated cmd args lineno')
151 # returns a generator out of the file object, which
152 # - removes `\\` then `\n` then a shared prefix with the previous line then optional whitespace;
153 # - keeps a line number (starting from 0) of the first line being concatenated.
154 def concat_multi_lines(f):
155 lastline = None # set to the last line when the last line has a backslash
158 for lineno, line in enumerate(f):
159 line = line.rstrip('\r\n')
161 # strip the common prefix from the current line if needed
162 if lastline is not None:
164 for i in xrange(min(len(line), len(lastline))):
165 if line[i] != lastline[i]: break
167 line = line[maxprefix:].lstrip()
169 firstlineno = firstlineno or lineno
170 if line.endswith('\\'):
172 catenated += line[:-1]
174 yield firstlineno, catenated + line
179 LINE_PATTERN = re.compile(r'''
180 (?<=(?<!\S)@)(?P<negated>!?)
181 (?P<cmd>[A-Za-z]+(?:-[A-Za-z]+)*)
184 def get_commands(template):
185 with open(template, 'rUb') as f:
186 for lineno, line in concat_multi_lines(f):
187 m = LINE_PATTERN.search(line)
190 negated = (m.group('negated') == '!')
192 args = m.group('args')
193 if args and not args[:1].isspace():
194 raise RuntimeError('Invalid template syntax at line {}'.format(lineno+1))
195 args = shlex.split(args)
196 yield Command(negated=negated, cmd=cmd, args=args, lineno=lineno+1)
198 def _flatten(node, acc):
199 if node.text: acc.append(node.text)
202 if e.tail: acc.append(e.tail)
209 def normalize_xpath(path):
210 if path.startswith('//'):
211 return '.' + path # avoid warnings
212 elif path.startswith('.//'):
215 raise RuntimeError('Non-absolute XPath is not supported due to \
216 the implementation issue.')
218 class CachedFiles(object):
219 def __init__(self, root):
223 self.last_path = None
225 def resolve_path(self, path):
227 path = os.path.normpath(path)
228 self.last_path = path
230 elif self.last_path is None:
231 raise RuntimeError('Tried to use the previous path in the first command')
233 return self.last_path
235 def get_file(self, path):
236 path = self.resolve_path(path)
238 return self.files[path]
241 with open(os.path.join(self.root, path)) as f:
243 except Exception as e:
244 raise RuntimeError('Cannot open file {!r}: {}'.format(path, e))
246 self.files[path] = data
249 def get_tree(self, path):
250 path = self.resolve_path(path)
252 return self.trees[path]
255 f = open(os.path.join(self.root, path))
256 except Exception as e:
257 raise RuntimeError('Cannot open file {!r}: {}'.format(path, e))
260 tree = ET.parse(f, CustomHTMLParser())
261 except Exception as e:
262 raise RuntimeError('Cannot parse an HTML file {!r}: {}'.format(path, e))
264 self.trees[path] = tree
265 return self.trees[path]
267 def check_string(data, pat, regexp):
269 return True # special case a presence testing
271 return re.search(pat, data) is not None
273 data = ' '.join(data.split())
274 pat = ' '.join(pat.split())
277 def check_tree_attr(tree, path, attr, pat, regexp):
278 path = normalize_xpath(path)
280 for e in tree.findall(path):
282 value = e.attrib[attr]
286 ret = check_string(value, pat, regexp)
290 def check_tree_text(tree, path, pat, regexp):
291 path = normalize_xpath(path)
293 for e in tree.findall(path):
299 ret = check_string(value, pat, regexp)
303 def check(target, commands):
304 cache = CachedFiles(target)
306 if c.cmd == 'has' or c.cmd == 'matches': # string test
307 regexp = (c.cmd == 'matches')
308 if len(c.args) == 1 and not regexp: # @has <path> = file existence
310 cache.get_file(c.args[0])
314 elif len(c.args) == 2: # @has/matches <path> <pat> = string test
315 ret = check_string(cache.get_file(c.args[0]), c.args[1], regexp)
316 elif len(c.args) == 3: # @has/matches <path> <pat> <match> = XML tree test
317 tree = cache.get_tree(c.args[0])
318 pat, sep, attr = c.args[1].partition('/@')
320 ret = check_tree_attr(cache.get_tree(c.args[0]), pat, attr, c.args[2], regexp)
321 else: # normalized text
323 if pat.endswith('/text()'): pat = pat[:-7]
324 ret = check_tree_text(cache.get_tree(c.args[0]), pat, c.args[2], regexp)
326 raise RuntimeError('Invalid number of @{} arguments \
327 at line {}'.format(c.cmd, c.lineno))
329 elif c.cmd == 'valid-html':
330 raise RuntimeError('Unimplemented @valid-html at line {}'.format(c.lineno))
332 elif c.cmd == 'valid-links':
333 raise RuntimeError('Unimplemented @valid-links at line {}'.format(c.lineno))
336 raise RuntimeError('Unrecognized @{} at line {}'.format(c.cmd, c.lineno))
339 raise RuntimeError('@{}{} check failed at line {}'.format('!' if c.negated else '',
342 if __name__ == '__main__':
343 if len(sys.argv) < 3:
344 print >>sys.stderr, 'Usage: {} <doc dir> <template>'.format(sys.argv[0])
347 check(sys.argv[1], get_commands(sys.argv[2]))