# Copyright 2015 The Rust Project Developers. See the COPYRIGHT # file at the top-level directory of this distribution and at # http://rust-lang.org/COPYRIGHT. # # Licensed under the Apache License, Version 2.0 or the MIT license # , at your # option. This file may not be copied, modified, or distributed # except according to those terms. r""" htmldocck.py is a custom checker script for Rustdoc HTML outputs. # How and why? The principle is simple: This script receives a path to generated HTML documentation and a "template" script, which has a series of check commands like `@has` or `@matches`. Each command can be used to check if some pattern is present or not present in the particular file or in the particular node of HTML tree. In many cases, the template script happens to be a source code given to rustdoc. While it indeed is possible to test in smaller portions, it has been hard to construct tests in this fashion and major rendering errors were discovered much later. This script is designed for making the black-box and regression testing of Rustdoc easy. This does not preclude the needs for unit testing, but can be used to complement related tests by quickly showing the expected renderings. In order to avoid one-off dependencies for this task, this script uses a reasonably working HTML parser and the existing XPath implementation from Python 2's standard library. Hopefully we won't render non-well-formed HTML. # Commands Commands start with an `@` followed by a command name (letters and hyphens), and zero or more arguments separated by one or more whitespace and optionally delimited with single or double quotes. The `@` mark cannot be preceded by a non-whitespace character. Other lines (including every text up to the first `@`) are ignored, but it is recommended to avoid the use of `@` in the template file. There are a number of supported commands: * `@has PATH` checks for the existence of given file. `PATH` is relative to the output directory. It can be given as `-` which repeats the most recently used `PATH`. * `@has PATH PATTERN` and `@matches PATH PATTERN` checks for the occurrence of given `PATTERN` in the given file. Only one occurrence of given pattern is enough. For `@has`, `PATTERN` is a whitespace-normalized (every consecutive whitespace being replaced by one single space character) string. The entire file is also whitespace-normalized including newlines. For `@matches`, `PATTERN` is a Python-supported regular expression. The file remains intact but the regexp is matched with no `MULTILINE` and `IGNORECASE` option. You can still use a prefix `(?m)` or `(?i)` to override them, and `\A` and `\Z` for definitely matching the beginning and end of the file. (The same distinction goes to other variants of these commands.) * `@has PATH XPATH PATTERN` and `@matches PATH XPATH PATTERN` checks for the presence of given `XPATH` in the given HTML file, and also the occurrence of given `PATTERN` in the matching node or attribute. Only one occurrence of given pattern in the match is enough. `PATH` should be a valid and well-formed HTML file. It does *not* accept arbitrary HTML5; it should have matching open and close tags and correct entity references at least. `XPATH` is an XPath expression to match. This is fairly limited: `tag`, `*`, `.`, `//`, `..`, `[@attr]`, `[@attr='value']`, `[tag]`, `[POS]` (element located in given `POS`), `[last()-POS]`, `text()` and `@attr` (both as the last segment) are supported. Some examples: - `//pre` or `.//pre` matches any element with a name `pre`. - `//a[@href]` matches any element with an `href` attribute. - `//*[@class="impl"]//code` matches any element with a name `code`, which is an ancestor of some element which `class` attr is `impl`. - `//h1[@class="fqn"]/span[1]/a[last()]/@class` matches a value of `class` attribute in the last `a` element (can be followed by more elements that are not `a`) inside the first `span` in the `h1` with a class of `fqn`. Note that there cannot be no additional elements between them due to the use of `/` instead of `//`. Do not try to use non-absolute paths, it won't work due to the flawed ElementTree implementation. The script rejects them. For the text matches (i.e. paths not ending with `@attr`), any subelements are flattened into one string; this is handy for ignoring highlights for example. If you want to simply check the presence of given node or attribute, use an empty string (`""`) as a `PATTERN`. * `@count PATH XPATH COUNT' checks for the occurrence of given XPath in the given file. The number of occurrences must match the given count. All conditions can be negated with `!`. `@!has foo/type.NoSuch.html` checks if the given file does not exist, for example. """ from __future__ import print_function import sys import os.path import re import shlex from collections import namedtuple from HTMLParser import HTMLParser from xml.etree import cElementTree as ET # ⇤/⇥ are not in HTML 4 but are in HTML 5 from htmlentitydefs import entitydefs entitydefs['larrb'] = u'\u21e4' entitydefs['rarrb'] = u'\u21e5' entitydefs['nbsp'] = ' ' # "void elements" (no closing tag) from the HTML Standard section 12.1.2 VOID_ELEMENTS = set(['area', 'base', 'br', 'col', 'embed', 'hr', 'img', 'input', 'keygen', 'link', 'menuitem', 'meta', 'param', 'source', 'track', 'wbr']) class CustomHTMLParser(HTMLParser): """simplified HTML parser. this is possible because we are dealing with very regular HTML from rustdoc; we only have to deal with i) void elements and ii) empty attributes.""" def __init__(self, target=None): HTMLParser.__init__(self) self.__builder = target or ET.TreeBuilder() def handle_starttag(self, tag, attrs): attrs = dict((k, v or '') for k, v in attrs) self.__builder.start(tag, attrs) if tag in VOID_ELEMENTS: self.__builder.end(tag) def handle_endtag(self, tag): self.__builder.end(tag) def handle_startendtag(self, tag, attrs): attrs = dict((k, v or '') for k, v in attrs) self.__builder.start(tag, attrs) self.__builder.end(tag) def handle_data(self, data): self.__builder.data(data) def handle_entityref(self, name): self.__builder.data(entitydefs[name]) def handle_charref(self, name): code = int(name[1:], 16) if name.startswith(('x', 'X')) else int(name, 10) self.__builder.data(unichr(code).encode('utf-8')) def close(self): HTMLParser.close(self) return self.__builder.close() Command = namedtuple('Command', 'negated cmd args lineno context') class FailedCheck(Exception): pass class InvalidCheck(Exception): pass def concat_multi_lines(f): """returns a generator out of the file object, which - removes `\\` then `\n` then a shared prefix with the previous line then optional whitespace; - keeps a line number (starting from 0) of the first line being concatenated.""" lastline = None # set to the last line when the last line has a backslash firstlineno = None catenated = '' for lineno, line in enumerate(f): line = line.rstrip('\r\n') # strip the common prefix from the current line if needed if lastline is not None: maxprefix = 0 for i in xrange(min(len(line), len(lastline))): if line[i] != lastline[i]: break maxprefix += 1 line = line[maxprefix:].lstrip() firstlineno = firstlineno or lineno if line.endswith('\\'): if lastline is None: lastline = line[:-1] catenated += line[:-1] else: yield firstlineno, catenated + line lastline = None firstlineno = None catenated = '' if lastline is not None: print_err(lineno, line, 'Trailing backslash at the end of the file') LINE_PATTERN = re.compile(r''' (?<=(?!?) (?P[A-Za-z]+(?:-[A-Za-z]+)*) (?P.*)$ ''', re.X) def get_commands(template): with open(template, 'rUb') as f: for lineno, line in concat_multi_lines(f): m = LINE_PATTERN.search(line) if not m: continue negated = (m.group('negated') == '!') cmd = m.group('cmd') args = m.group('args') if args and not args[:1].isspace(): print_err(lineno, line, 'Invalid template syntax') continue args = shlex.split(args) yield Command(negated=negated, cmd=cmd, args=args, lineno=lineno+1, context=line) def _flatten(node, acc): if node.text: acc.append(node.text) for e in node: _flatten(e, acc) if e.tail: acc.append(e.tail) def flatten(node): acc = [] _flatten(node, acc) return ''.join(acc) def normalize_xpath(path): if path.startswith('//'): return '.' + path # avoid warnings elif path.startswith('.//'): return path else: raise InvalidCheck('Non-absolute XPath is not supported due to implementation issues') class CachedFiles(object): def __init__(self, root): self.root = root self.files = {} self.trees = {} self.last_path = None def resolve_path(self, path): if path != '-': path = os.path.normpath(path) self.last_path = path return path elif self.last_path is None: raise InvalidCheck('Tried to use the previous path in the first command') else: return self.last_path def get_file(self, path): path = self.resolve_path(path) if path in self.files: return self.files[path] abspath = os.path.join(self.root, path) if not(os.path.exists(abspath) and os.path.isfile(abspath)): raise FailedCheck('File does not exist {!r}'.format(path)) with open(abspath) as f: data = f.read() self.files[path] = data return data def get_tree(self, path): path = self.resolve_path(path) if path in self.trees: return self.trees[path] abspath = os.path.join(self.root, path) if not(os.path.exists(abspath) and os.path.isfile(abspath)): raise FailedCheck('File does not exist {!r}'.format(path)) with open(abspath) as f: try: tree = ET.parse(f, CustomHTMLParser()) except Exception as e: raise RuntimeError('Cannot parse an HTML file {!r}: {}'.format(path, e)) self.trees[path] = tree return self.trees[path] def check_string(data, pat, regexp): if not pat: return True # special case a presence testing elif regexp: return re.search(pat, data) is not None else: data = ' '.join(data.split()) pat = ' '.join(pat.split()) return pat in data def check_tree_attr(tree, path, attr, pat, regexp): path = normalize_xpath(path) ret = False for e in tree.findall(path): if attr in e.attrib: value = e.attrib[attr] else: continue ret = check_string(value, pat, regexp) if ret: break return ret def check_tree_text(tree, path, pat, regexp): path = normalize_xpath(path) ret = False for e in tree.findall(path): try: value = flatten(e) except KeyError: continue else: ret = check_string(value, pat, regexp) if ret: break return ret def get_tree_count(tree, path): path = normalize_xpath(path) return len(tree.findall(path)) def stderr(*args): print(*args, file=sys.stderr) def print_err(lineno, context, err, message=None): global ERR_COUNT ERR_COUNT += 1 stderr("{}: {}".format(lineno, message or err)) if message and err: stderr("\t{}".format(err)) if context: stderr("\t{}".format(context)) ERR_COUNT = 0 def check_command(c, cache): try: cerr = "" if c.cmd == 'has' or c.cmd == 'matches': # string test regexp = (c.cmd == 'matches') if len(c.args) == 1 and not regexp: # @has = file existence try: cache.get_file(c.args[0]) ret = True except FailedCheck as err: cerr = err.message ret = False elif len(c.args) == 2: # @has/matches = string test cerr = "`PATTERN` did not match" ret = check_string(cache.get_file(c.args[0]), c.args[1], regexp) elif len(c.args) == 3: # @has/matches = XML tree test cerr = "`XPATH PATTERN` did not match" tree = cache.get_tree(c.args[0]) pat, sep, attr = c.args[1].partition('/@') if sep: # attribute tree = cache.get_tree(c.args[0]) ret = check_tree_attr(tree, pat, attr, c.args[2], regexp) else: # normalized text pat = c.args[1] if pat.endswith('/text()'): pat = pat[:-7] ret = check_tree_text(cache.get_tree(c.args[0]), pat, c.args[2], regexp) else: raise InvalidCheck('Invalid number of @{} arguments'.format(c.cmd)) elif c.cmd == 'count': # count test if len(c.args) == 3: # @count = count test expected = int(c.args[2]) found = get_tree_count(cache.get_tree(c.args[0]), c.args[1]) cerr = "Expected {} occurrences but found {}".format(expected, found) ret = expected == found else: raise InvalidCheck('Invalid number of @{} arguments'.format(c.cmd)) elif c.cmd == 'valid-html': raise InvalidCheck('Unimplemented @valid-html') elif c.cmd == 'valid-links': raise InvalidCheck('Unimplemented @valid-links') else: raise InvalidCheck('Unrecognized @{}'.format(c.cmd)) if ret == c.negated: raise FailedCheck(cerr) except FailedCheck as err: message = '@{}{} check failed'.format('!' if c.negated else '', c.cmd) print_err(c.lineno, c.context, err.message, message) except InvalidCheck as err: print_err(c.lineno, c.context, err.message) def check(target, commands): cache = CachedFiles(target) for c in commands: check_command(c, cache) if __name__ == '__main__': if len(sys.argv) != 3: stderr('Usage: {}