#!/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="""
<tr><td>%(result)s</td><td class="name" onclick="toggle('%(id)s')"><a name="%(id)sAnchor">%(name)s</a></td><td>%(args)s</td></tr>
<tr><td colspan="4" class="doc" id="%(id)s"><pre>%(comment)s</pre></td></tr>
"""
# 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<<a href="%s">%s</a>>' % (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<T1>[, Matcher<t2>[, ...]])
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<ResultType, ArgumentType> 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<Type>', comment)
if loc:
add_matcher('%sLoc' % result_type, '%sLoc' % name, 'Matcher<TypeLoc>',
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<ResultType> Name(Matcher<ArgumentType> 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 ('<!-- START_%(type)s_MATCHERS -->\n' +
'%(table)s' +
'<!--END_%(type)s_MATCHERS -->') % {
'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'<!-- START_DECL_MATCHERS.*END_DECL_MATCHERS -->',
'%s', reference, flags=re.S) % node_matcher_table
reference = re.sub(r'<!-- START_NARROWING_MATCHERS.*END_NARROWING_MATCHERS -->',
'%s', reference, flags=re.S) % narrowing_matcher_table
reference = re.sub(r'<!-- START_TRAVERSAL_MATCHERS.*END_TRAVERSAL_MATCHERS -->',
'%s', reference, flags=re.S) % traversal_matcher_table
with open('../LibASTMatchersReference.html', 'w') as output:
output.write(reference)