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author | alexv-smirnov <alex@ydb.tech> | 2023-06-13 11:05:01 +0300 |
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committer | alexv-smirnov <alex@ydb.tech> | 2023-06-13 11:05:01 +0300 |
commit | bf0f13dd39ee3e65092ba3572bb5b1fcd125dcd0 (patch) | |
tree | 1d1df72c0541a59a81439842f46d95396d3e7189 /contrib/tools/cython/Cython/Compiler/TreePath.py | |
parent | 8bfdfa9a9bd19bddbc58d888e180fbd1218681be (diff) | |
download | ydb-bf0f13dd39ee3e65092ba3572bb5b1fcd125dcd0.tar.gz |
add ymake export to ydb
Diffstat (limited to 'contrib/tools/cython/Cython/Compiler/TreePath.py')
-rw-r--r-- | contrib/tools/cython/Cython/Compiler/TreePath.py | 296 |
1 files changed, 296 insertions, 0 deletions
diff --git a/contrib/tools/cython/Cython/Compiler/TreePath.py b/contrib/tools/cython/Cython/Compiler/TreePath.py new file mode 100644 index 0000000000..8585905557 --- /dev/null +++ b/contrib/tools/cython/Cython/Compiler/TreePath.py @@ -0,0 +1,296 @@ +""" +A simple XPath-like language for tree traversal. + +This works by creating a filter chain of generator functions. Each +function selects a part of the expression, e.g. a child node, a +specific descendant or a node that holds an attribute. +""" + +from __future__ import absolute_import + +import re +import operator +import sys + +if sys.version_info[0] >= 3: + _unicode = str +else: + _unicode = unicode + +path_tokenizer = re.compile( + r"(" + r"'[^']*'|\"[^\"]*\"|" + r"//?|" + r"\(\)|" + r"==?|" + r"[/.*\[\]()@])|" + r"([^/\[\]()@=\s]+)|" + r"\s+" + ).findall + +def iterchildren(node, attr_name): + # returns an iterable of all child nodes of that name + child = getattr(node, attr_name) + if child is not None: + if type(child) is list: + return child + else: + return [child] + else: + return () + +def _get_first_or_none(it): + try: + try: + _next = it.next + except AttributeError: + return next(it) + else: + return _next() + except StopIteration: + return None + +def type_name(node): + return node.__class__.__name__.split('.')[-1] + +def parse_func(next, token): + name = token[1] + token = next() + if token[0] != '(': + raise ValueError("Expected '(' after function name '%s'" % name) + predicate = handle_predicate(next, token) + return name, predicate + +def handle_func_not(next, token): + """ + not(...) + """ + name, predicate = parse_func(next, token) + + def select(result): + for node in result: + if _get_first_or_none(predicate([node])) is None: + yield node + return select + +def handle_name(next, token): + """ + /NodeName/ + or + func(...) + """ + name = token[1] + if name in functions: + return functions[name](next, token) + def select(result): + for node in result: + for attr_name in node.child_attrs: + for child in iterchildren(node, attr_name): + if type_name(child) == name: + yield child + return select + +def handle_star(next, token): + """ + /*/ + """ + def select(result): + for node in result: + for name in node.child_attrs: + for child in iterchildren(node, name): + yield child + return select + +def handle_dot(next, token): + """ + /./ + """ + def select(result): + return result + return select + +def handle_descendants(next, token): + """ + //... + """ + token = next() + if token[0] == "*": + def iter_recursive(node): + for name in node.child_attrs: + for child in iterchildren(node, name): + yield child + for c in iter_recursive(child): + yield c + elif not token[0]: + node_name = token[1] + def iter_recursive(node): + for name in node.child_attrs: + for child in iterchildren(node, name): + if type_name(child) == node_name: + yield child + for c in iter_recursive(child): + yield c + else: + raise ValueError("Expected node name after '//'") + + def select(result): + for node in result: + for child in iter_recursive(node): + yield child + + return select + + +def handle_attribute(next, token): + token = next() + if token[0]: + raise ValueError("Expected attribute name") + name = token[1] + value = None + try: + token = next() + except StopIteration: + pass + else: + if token[0] == '=': + value = parse_path_value(next) + readattr = operator.attrgetter(name) + if value is None: + def select(result): + for node in result: + try: + attr_value = readattr(node) + except AttributeError: + continue + if attr_value is not None: + yield attr_value + else: + def select(result): + for node in result: + try: + attr_value = readattr(node) + except AttributeError: + continue + if attr_value == value: + yield attr_value + elif (isinstance(attr_value, bytes) and isinstance(value, _unicode) and + attr_value == value.encode()): + # allow a bytes-to-string comparison too + yield attr_value + + return select + + +def parse_path_value(next): + token = next() + value = token[0] + if value: + if value[:1] == "'" or value[:1] == '"': + return value[1:-1] + try: + return int(value) + except ValueError: + pass + elif token[1].isdigit(): + return int(token[1]) + else: + name = token[1].lower() + if name == 'true': + return True + elif name == 'false': + return False + raise ValueError("Invalid attribute predicate: '%s'" % value) + +def handle_predicate(next, token): + token = next() + selector = [] + while token[0] != ']': + selector.append( operations[token[0]](next, token) ) + try: + token = next() + except StopIteration: + break + else: + if token[0] == "/": + token = next() + + if not token[0] and token[1] == 'and': + return logical_and(selector, handle_predicate(next, token)) + + def select(result): + for node in result: + subresult = iter((node,)) + for select in selector: + subresult = select(subresult) + predicate_result = _get_first_or_none(subresult) + if predicate_result is not None: + yield node + return select + +def logical_and(lhs_selects, rhs_select): + def select(result): + for node in result: + subresult = iter((node,)) + for select in lhs_selects: + subresult = select(subresult) + predicate_result = _get_first_or_none(subresult) + subresult = iter((node,)) + if predicate_result is not None: + for result_node in rhs_select(subresult): + yield node + return select + + +operations = { + "@": handle_attribute, + "": handle_name, + "*": handle_star, + ".": handle_dot, + "//": handle_descendants, + "[": handle_predicate, + } + +functions = { + 'not' : handle_func_not + } + +def _build_path_iterator(path): + # parse pattern + stream = iter([ (special,text) + for (special,text) in path_tokenizer(path) + if special or text ]) + try: + _next = stream.next + except AttributeError: + # Python 3 + def _next(): + return next(stream) + token = _next() + selector = [] + while 1: + try: + selector.append(operations[token[0]](_next, token)) + except StopIteration: + raise ValueError("invalid path") + try: + token = _next() + if token[0] == "/": + token = _next() + except StopIteration: + break + return selector + +# main module API + +def iterfind(node, path): + selector_chain = _build_path_iterator(path) + result = iter((node,)) + for select in selector_chain: + result = select(result) + return result + +def find_first(node, path): + return _get_first_or_none(iterfind(node, path)) + +def find_all(node, path): + return list(iterfind(node, path)) |