diff options
Diffstat (limited to 'powerline/lint/markedjson/parser.py')
| -rw-r--r-- | powerline/lint/markedjson/parser.py | 255 |
1 files changed, 255 insertions, 0 deletions
diff --git a/powerline/lint/markedjson/parser.py b/powerline/lint/markedjson/parser.py new file mode 100644 index 0000000..336a2a2 --- /dev/null +++ b/powerline/lint/markedjson/parser.py @@ -0,0 +1,255 @@ +# vim:fileencoding=utf-8:noet +from __future__ import (unicode_literals, division, absolute_import, print_function) + +from powerline.lint.markedjson.error import MarkedError +from powerline.lint.markedjson import tokens +from powerline.lint.markedjson import events + + +class ParserError(MarkedError): + pass + + +class Parser: + def __init__(self): + self.current_event = None + self.yaml_version = None + self.states = [] + self.marks = [] + self.state = self.parse_stream_start + + def dispose(self): + # Reset the state attributes (to clear self-references) + self.states = [] + self.state = None + + def check_event(self, *choices): + # Check the type of the next event. + if self.current_event is None: + if self.state: + self.current_event = self.state() + if self.current_event is not None: + if not choices: + return True + for choice in choices: + if isinstance(self.current_event, choice): + return True + return False + + def peek_event(self): + # Get the next event. + if self.current_event is None: + if self.state: + self.current_event = self.state() + return self.current_event + + def get_event(self): + # Get the next event and proceed further. + if self.current_event is None: + if self.state: + self.current_event = self.state() + value = self.current_event + self.current_event = None + return value + + # stream ::= STREAM-START implicit_document? explicit_document* STREAM-END + # implicit_document ::= block_node DOCUMENT-END* + # explicit_document ::= DIRECTIVE* DOCUMENT-START block_node? DOCUMENT-END* + + def parse_stream_start(self): + # Parse the stream start. + token = self.get_token() + event = events.StreamStartEvent(token.start_mark, token.end_mark, encoding=token.encoding) + + # Prepare the next state. + self.state = self.parse_implicit_document_start + + return event + + def parse_implicit_document_start(self): + # Parse an implicit document. + if not self.check_token(tokens.StreamEndToken): + token = self.peek_token() + start_mark = end_mark = token.start_mark + event = events.DocumentStartEvent(start_mark, end_mark, explicit=False) + + # Prepare the next state. + self.states.append(self.parse_document_end) + self.state = self.parse_node + + return event + + else: + return self.parse_document_start() + + def parse_document_start(self): + # Parse an explicit document. + if not self.check_token(tokens.StreamEndToken): + token = self.peek_token() + self.echoerr( + None, None, + ('expected \'<stream end>\', but found %r' % token.id), token.start_mark + ) + return events.StreamEndEvent(token.start_mark, token.end_mark) + else: + # Parse the end of the stream. + token = self.get_token() + event = events.StreamEndEvent(token.start_mark, token.end_mark) + assert not self.states + assert not self.marks + self.state = None + return event + + def parse_document_end(self): + # Parse the document end. + token = self.peek_token() + start_mark = end_mark = token.start_mark + explicit = False + event = events.DocumentEndEvent(start_mark, end_mark, explicit=explicit) + + # Prepare the next state. + self.state = self.parse_document_start + + return event + + def parse_document_content(self): + return self.parse_node() + + def parse_node(self, indentless_sequence=False): + start_mark = end_mark = None + if start_mark is None: + start_mark = end_mark = self.peek_token().start_mark + event = None + implicit = True + if self.check_token(tokens.ScalarToken): + token = self.get_token() + end_mark = token.end_mark + if token.plain: + implicit = (True, False) + else: + implicit = (False, True) + event = events.ScalarEvent(implicit, token.value, start_mark, end_mark, style=token.style) + self.state = self.states.pop() + elif self.check_token(tokens.FlowSequenceStartToken): + end_mark = self.peek_token().end_mark + event = events.SequenceStartEvent(implicit, start_mark, end_mark, flow_style=True) + self.state = self.parse_flow_sequence_first_entry + elif self.check_token(tokens.FlowMappingStartToken): + end_mark = self.peek_token().end_mark + event = events.MappingStartEvent(implicit, start_mark, end_mark, flow_style=True) + self.state = self.parse_flow_mapping_first_key + else: + token = self.peek_token() + raise ParserError( + 'while parsing a flow node', start_mark, + 'expected the node content, but found %r' % token.id, + token.start_mark + ) + return event + + def parse_flow_sequence_first_entry(self): + token = self.get_token() + self.marks.append(token.start_mark) + return self.parse_flow_sequence_entry(first=True) + + def parse_flow_sequence_entry(self, first=False): + if not self.check_token(tokens.FlowSequenceEndToken): + if not first: + if self.check_token(tokens.FlowEntryToken): + self.get_token() + if self.check_token(tokens.FlowSequenceEndToken): + token = self.peek_token() + self.echoerr( + 'While parsing a flow sequence', self.marks[-1], + ('expected sequence value, but got %r' % token.id), token.start_mark + ) + else: + token = self.peek_token() + raise ParserError( + 'while parsing a flow sequence', self.marks[-1], + ('expected \',\' or \']\', but got %r' % token.id), token.start_mark + ) + + if not self.check_token(tokens.FlowSequenceEndToken): + self.states.append(self.parse_flow_sequence_entry) + return self.parse_node() + token = self.get_token() + event = events.SequenceEndEvent(token.start_mark, token.end_mark) + self.state = self.states.pop() + self.marks.pop() + return event + + def parse_flow_sequence_entry_mapping_end(self): + self.state = self.parse_flow_sequence_entry + token = self.peek_token() + return events.MappingEndEvent(token.start_mark, token.start_mark) + + def parse_flow_mapping_first_key(self): + token = self.get_token() + self.marks.append(token.start_mark) + return self.parse_flow_mapping_key(first=True) + + def parse_flow_mapping_key(self, first=False): + if not self.check_token(tokens.FlowMappingEndToken): + if not first: + if self.check_token(tokens.FlowEntryToken): + self.get_token() + if self.check_token(tokens.FlowMappingEndToken): + token = self.peek_token() + self.echoerr( + 'While parsing a flow mapping', self.marks[-1], + ('expected mapping key, but got %r' % token.id), token.start_mark + ) + else: + token = self.peek_token() + raise ParserError( + 'while parsing a flow mapping', self.marks[-1], + ('expected \',\' or \'}\', but got %r' % token.id), token.start_mark + ) + if self.check_token(tokens.KeyToken): + token = self.get_token() + if not self.check_token(tokens.ValueToken, tokens.FlowEntryToken, tokens.FlowMappingEndToken): + self.states.append(self.parse_flow_mapping_value) + return self.parse_node() + else: + token = self.peek_token() + raise ParserError( + 'while parsing a flow mapping', self.marks[-1], + ('expected value, but got %r' % token.id), token.start_mark + ) + elif not self.check_token(tokens.FlowMappingEndToken): + token = self.peek_token() + expect_key = self.check_token(tokens.ValueToken, tokens.FlowEntryToken) + if not expect_key: + self.get_token() + expect_key = self.check_token(tokens.ValueToken) + + if expect_key: + raise ParserError( + 'while parsing a flow mapping', self.marks[-1], + ('expected string key, but got %r' % token.id), token.start_mark + ) + else: + token = self.peek_token() + raise ParserError( + 'while parsing a flow mapping', self.marks[-1], + ('expected \':\', but got %r' % token.id), token.start_mark + ) + token = self.get_token() + event = events.MappingEndEvent(token.start_mark, token.end_mark) + self.state = self.states.pop() + self.marks.pop() + return event + + def parse_flow_mapping_value(self): + if self.check_token(tokens.ValueToken): + token = self.get_token() + if not self.check_token(tokens.FlowEntryToken, tokens.FlowMappingEndToken): + self.states.append(self.parse_flow_mapping_key) + return self.parse_node() + + token = self.peek_token() + raise ParserError( + 'while parsing a flow mapping', self.marks[-1], + ('expected mapping value, but got %r' % token.id), token.start_mark + ) |