#!/usr/bin/env python # A tool to parse ASTMatchers.h and update the documentation in # ../LibASTMatchersReference.html automatically. Run from the # directory in which this file is located to update the docs. import collections import re import urllib2 MATCHERS_FILE = '../../include/clang/ASTMatchers/ASTMatchers.h' # Each matcher is documented in one row of the form: # result | name | argA # The subsequent row contains the documentation and is hidden by default, # becoming visible via javascript when the user clicks the matcher name. TD_TEMPLATE=""" %(result)s%(name)s%(args)s
%(comment)s
""" # We categorize the matchers into these three categories in the reference: node_matchers = {} narrowing_matchers = {} traversal_matchers = {} # We output multiple rows per matcher if the matcher can be used on multiple # node types. Thus, we need a new id per row to control the documentation # pop-up. ids[name] keeps track of those ids. ids = collections.defaultdict(int) # Cache for doxygen urls we have already verified. doxygen_probes = {} def esc(text): """Escape any html in the given text.""" text = re.sub(r'&', '&', text) text = re.sub(r'<', '<', text) text = re.sub(r'>', '>', text) def link_if_exists(m): name = m.group(1) url = 'http://clang.llvm.org/doxygen/classclang_1_1%s.html' % name if url not in doxygen_probes: try: print 'Probing %s...' % url urllib2.urlopen(url) doxygen_probes[url] = True except: doxygen_probes[url] = False if doxygen_probes[url]: return r'Matcher<%s>' % (url, name) else: return m.group(0) text = re.sub( r'Matcher<([^\*&]+)>', link_if_exists, text) return text def extract_result_types(comment): """Extracts a list of result types from the given comment. We allow annotations in the comment of the matcher to specify what nodes a matcher can match on. Those comments have the form: Usable as: Any Matcher | (Matcher[, Matcher[, ...]]) Returns ['*'] in case of 'Any Matcher', or ['T1', 'T2', ...]. Returns the empty list if no 'Usable as' specification could be parsed. """ result_types = [] m = re.search(r'Usable as: Any Matcher[\s\n]*$', comment, re.S) if m: return ['*'] while True: m = re.match(r'^(.*)Matcher<([^>]+)>\s*,?[\s\n]*$', comment, re.S) if not m: if re.search(r'Usable as:\s*$', comment): return result_types else: return None result_types += [m.group(2)] comment = m.group(1) def strip_doxygen(comment): """Returns the given comment without \-escaped words.""" # If there is only a doxygen keyword in the line, delete the whole line. comment = re.sub(r'^\\[^\s]+\n', r'', comment, flags=re.M) # Delete the doxygen command and the following whitespace. comment = re.sub(r'\\[^\s]+\s+', r'', comment) return comment def unify_arguments(args): """Gets rid of anything the user doesn't care about in the argument list.""" args = re.sub(r'internal::', r'', args) args = re.sub(r'const\s+', r'', args) args = re.sub(r'&', r' ', args) args = re.sub(r'(^|\s)M\d?(\s)', r'\1Matcher<*>\2', args) return args def add_matcher(result_type, name, args, comment, is_dyncast=False): """Adds a matcher to one of our categories.""" if name == 'id': # FIXME: Figure out whether we want to support the 'id' matcher. return matcher_id = '%s%d' % (name, ids[name]) ids[name] += 1 args = unify_arguments(args) matcher_html = TD_TEMPLATE % { 'result': esc('Matcher<%s>' % result_type), 'name': name, 'args': esc(args), 'comment': esc(strip_doxygen(comment)), 'id': matcher_id, } if is_dyncast: node_matchers[result_type + name] = matcher_html # Use a heuristic to figure out whether a matcher is a narrowing or # traversal matcher. By default, matchers that take other matchers as # arguments (and are not node matchers) do traversal. We specifically # exclude known narrowing matchers that also take other matchers as # arguments. elif ('Matcher<' not in args or name in ['allOf', 'anyOf', 'anything', 'unless']): narrowing_matchers[result_type + name] = matcher_html else: traversal_matchers[result_type + name] = matcher_html def act_on_decl(declaration, comment, allowed_types): """Parse the matcher out of the given declaration and comment. If 'allowed_types' is set, it contains a list of node types the matcher can match on, as extracted from the static type asserts in the matcher definition. """ if declaration.strip(): # Node matchers are defined by writing: # VariadicDynCastAllOfMatcher name; m = re.match(r""".*Variadic(?:DynCast)?AllOfMatcher\s*< \s*([^\s,]+)\s*(?:, \s*([^\s>]+)\s*)?> \s*([^\s;]+)\s*;\s*$""", declaration, flags=re.X) if m: result, inner, name = m.groups() if not inner: inner = result add_matcher(result, name, 'Matcher<%s>...' % inner, comment, is_dyncast=True) return # Parse the various matcher definition macros. m = re.match(""".*AST_TYPE_MATCHER\( \s*([^\s,]+\s*), \s*([^\s,]+\s*) \)\s*;\s*$""", declaration, flags=re.X) if m: inner, name = m.groups() add_matcher('Type', name, 'Matcher<%s>...' % inner, comment, is_dyncast=True) add_matcher('TypeLoc', '%sLoc' % name, 'Matcher<%sLoc>...' % inner, comment, is_dyncast=True) return m = re.match(""".*AST_TYPE(LOC)?_TRAVERSE_MATCHER\( \s*([^\s,]+\s*), \s*(?:[^\s,]+\s*) \)\s*;\s*$""", declaration, flags=re.X) if m: loc = m.group(1) name = m.group(2) result_types = extract_result_types(comment) if not result_types: raise Exception('Did not find allowed result types for: %s' % name) for result_type in result_types: add_matcher(result_type, name, 'Matcher', comment) if loc: add_matcher('%sLoc' % result_type, '%sLoc' % name, 'Matcher', comment) return m = re.match(r"""^\s*AST_(POLYMORPHIC_)?MATCHER(_P)?(.?)(?:_OVERLOAD)?\( (?:\s*([^\s,]+)\s*,)? \s*([^\s,]+)\s* (?:,\s*([^\s,]+)\s* ,\s*([^\s,]+)\s*)? (?:,\s*([^\s,]+)\s* ,\s*([^\s,]+)\s*)? (?:,\s*\d+\s*)? \)\s*{\s*$""", declaration, flags=re.X) if m: p, n, result, name = m.groups()[1:5] args = m.groups()[5:] if not result: if not allowed_types: raise Exception('Did not find allowed result types for: %s' % name) result_types = allowed_types else: result_types = [result] if n not in ['', '2']: raise Exception('Cannot parse "%s"' % declaration) args = ', '.join('%s %s' % (args[i], args[i+1]) for i in range(0, len(args), 2) if args[i]) for result_type in result_types: add_matcher(result_type, name, args, comment) return # Parse free standing matcher functions, like: # Matcher Name(Matcher InnerMatcher) { m = re.match(r"""^\s*(.*)\s+ ([^\s\(]+)\s*\( (.*) \)\s*{""", declaration, re.X) if m: result, name, args = m.groups() args = ', '.join(p.strip() for p in args.split(',')) m = re.match(r'.*\s+internal::(Bindable)?Matcher<([^>]+)>$', result) if m: result_types = [m.group(2)] else: result_types = extract_result_types(comment) if not result_types: if not comment: # Only overloads don't have their own doxygen comments; ignore those. print 'Ignoring "%s"' % name else: print 'Cannot determine result type for "%s"' % name else: for result_type in result_types: add_matcher(result_type, name, args, comment) else: print '*** Unparsable: "' + declaration + '" ***' def sort_table(matcher_type, matcher_map): """Returns the sorted html table for the given row map.""" table = '' for key in sorted(matcher_map.keys()): table += matcher_map[key] + '\n' return ('\n' + '%(table)s' + '') % { 'type': matcher_type, 'table': table, } # Parse the ast matchers. # We alternate between two modes: # body = True: We parse the definition of a matcher. We need # to parse the full definition before adding a matcher, as the # definition might contain static asserts that specify the result # type. # body = False: We parse the comments and declaration of the matcher. comment = '' declaration = '' allowed_types = [] body = False for line in open(MATCHERS_FILE).read().splitlines(): if body: if line.strip() and line[0] == '}': if declaration: act_on_decl(declaration, comment, allowed_types) comment = '' declaration = '' allowed_types = [] body = False else: m = re.search(r'is_base_of<([^,]+), NodeType>', line) if m and m.group(1): allowed_types += [m.group(1)] continue if line.strip() and line.lstrip()[0] == '/': comment += re.sub(r'/+\s?', '', line) + '\n' else: declaration += ' ' + line if ((not line.strip()) or line.rstrip()[-1] == ';' or line.rstrip()[-1] == '{'): if line.strip() and line.rstrip()[-1] == '{': body = True else: act_on_decl(declaration, comment, allowed_types) comment = '' declaration = '' allowed_types = [] node_matcher_table = sort_table('DECL', node_matchers) narrowing_matcher_table = sort_table('NARROWING', narrowing_matchers) traversal_matcher_table = sort_table('TRAVERSAL', traversal_matchers) reference = open('../LibASTMatchersReference.html').read() reference = re.sub(r'', '%s', reference, flags=re.S) % node_matcher_table reference = re.sub(r'', '%s', reference, flags=re.S) % narrowing_matcher_table reference = re.sub(r'', '%s', reference, flags=re.S) % traversal_matcher_table with open('../LibASTMatchersReference.html', 'w') as output: output.write(reference)