mirror of
https://github.com/The-OpenROAD-Project/OpenLane.git
synced 2026-05-29 00:23:55 +08:00
bb89ac959a
Please excuse the last commit lacking a changelog. + PDK installation uses Volare, transparently to the user: all they have to do is type "make", where it will get OpenLane and the PDK + CI now uses Volare to either **get** or **build** the PDK (if not found), which speeds up the fastest test set by around 60%. + Added rudimentary dependency installation instructions. + pyyaml folded into the repo, so users without pip can still run issue surveys ~ Open PDKs updated: Parasitics are now extracted using a rules file based on [spef-extractor](https://github.com/Cloud-V/spef-extractor) as a ***temporary*** measure ~ Issue survey no longer checks for click and pyyaml: a venv is used in those scenarios. ~ OpenLane build no longer uses the host filesystem as an intermediary, instead using a templated dockerfile with an N-stage build for N tools, saving IO operations (40% improvement measured) ~ Old PDK targets renamed to build-pdk-conda, includes SRAM by default ~ Replaced python3 ./env.py issue-survey with `make survey` - Removed Fault from documentation (until I get the chance to work on it)
1556 lines
52 KiB
Python
1556 lines
52 KiB
Python
# Scanner produces tokens of the following types:
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# STREAM-START
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# STREAM-END
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# DIRECTIVE(name, value)
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# DOCUMENT-START
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# DOCUMENT-END
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# BLOCK-SEQUENCE-START
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# BLOCK-MAPPING-START
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# BLOCK-END
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# FLOW-SEQUENCE-START
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# FLOW-MAPPING-START
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# FLOW-SEQUENCE-END
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# FLOW-MAPPING-END
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# BLOCK-ENTRY
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# FLOW-ENTRY
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# KEY
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# VALUE
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# ALIAS(value)
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# ANCHOR(value)
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# TAG(value)
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# SCALAR(value, plain, style)
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#
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# Read comments in the Scanner code for more details.
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#
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__all__ = ["Scanner", "ScannerError"]
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from .error import MarkedYAMLError
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from .tokens import *
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class ScannerError(MarkedYAMLError):
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pass
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class SimpleKey:
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# See below simple keys treatment.
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def __init__(self, token_number, required, index, line, column, mark):
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self.token_number = token_number
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self.required = required
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self.index = index
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self.line = line
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self.column = column
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self.mark = mark
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class Scanner:
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def __init__(self):
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"""Initialize the scanner."""
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# It is assumed that Scanner and Reader will have a common descendant.
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# Reader do the dirty work of checking for BOM and converting the
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# input data to Unicode. It also adds NUL to the end.
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#
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# Reader supports the following methods
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# self.peek(i=0) # peek the next i-th character
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# self.prefix(l=1) # peek the next l characters
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# self.forward(l=1) # read the next l characters and move the pointer.
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# Had we reached the end of the stream?
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self.done = False
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# The number of unclosed '{' and '['. `flow_level == 0` means block
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# context.
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self.flow_level = 0
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# List of processed tokens that are not yet emitted.
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self.tokens = []
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# Add the STREAM-START token.
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self.fetch_stream_start()
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# Number of tokens that were emitted through the `get_token` method.
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self.tokens_taken = 0
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# The current indentation level.
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self.indent = -1
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# Past indentation levels.
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self.indents = []
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# Variables related to simple keys treatment.
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# A simple key is a key that is not denoted by the '?' indicator.
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# Example of simple keys:
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# ---
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# block simple key: value
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# ? not a simple key:
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# : { flow simple key: value }
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# We emit the KEY token before all keys, so when we find a potential
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# simple key, we try to locate the corresponding ':' indicator.
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# Simple keys should be limited to a single line and 1024 characters.
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# Can a simple key start at the current position? A simple key may
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# start:
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# - at the beginning of the line, not counting indentation spaces
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# (in block context),
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# - after '{', '[', ',' (in the flow context),
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# - after '?', ':', '-' (in the block context).
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# In the block context, this flag also signifies if a block collection
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# may start at the current position.
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self.allow_simple_key = True
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# Keep track of possible simple keys. This is a dictionary. The key
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# is `flow_level`; there can be no more that one possible simple key
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# for each level. The value is a SimpleKey record:
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# (token_number, required, index, line, column, mark)
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# A simple key may start with ALIAS, ANCHOR, TAG, SCALAR(flow),
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# '[', or '{' tokens.
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self.possible_simple_keys = {}
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# Public methods.
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def check_token(self, *choices):
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# Check if the next token is one of the given types.
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while self.need_more_tokens():
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self.fetch_more_tokens()
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if self.tokens:
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if not choices:
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return True
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for choice in choices:
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if isinstance(self.tokens[0], choice):
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return True
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return False
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def peek_token(self):
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# Return the next token, but do not delete if from the queue.
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# Return None if no more tokens.
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while self.need_more_tokens():
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self.fetch_more_tokens()
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if self.tokens:
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return self.tokens[0]
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else:
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return None
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def get_token(self):
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# Return the next token.
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while self.need_more_tokens():
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self.fetch_more_tokens()
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if self.tokens:
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self.tokens_taken += 1
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return self.tokens.pop(0)
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# Private methods.
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def need_more_tokens(self):
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if self.done:
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return False
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if not self.tokens:
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return True
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# The current token may be a potential simple key, so we
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# need to look further.
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self.stale_possible_simple_keys()
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if self.next_possible_simple_key() == self.tokens_taken:
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return True
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def fetch_more_tokens(self):
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# Eat whitespaces and comments until we reach the next token.
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self.scan_to_next_token()
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# Remove obsolete possible simple keys.
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self.stale_possible_simple_keys()
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# Compare the current indentation and column. It may add some tokens
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# and decrease the current indentation level.
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self.unwind_indent(self.column)
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# Peek the next character.
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ch = self.peek()
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# Is it the end of stream?
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if ch == "\0":
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return self.fetch_stream_end()
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# Is it a directive?
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if ch == "%" and self.check_directive():
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return self.fetch_directive()
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# Is it the document start?
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if ch == "-" and self.check_document_start():
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return self.fetch_document_start()
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# Is it the document end?
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if ch == "." and self.check_document_end():
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return self.fetch_document_end()
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# TODO: support for BOM within a stream.
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# if ch == '\uFEFF':
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# return self.fetch_bom() <-- issue BOMToken
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# Note: the order of the following checks is NOT significant.
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# Is it the flow sequence start indicator?
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if ch == "[":
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return self.fetch_flow_sequence_start()
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# Is it the flow mapping start indicator?
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if ch == "{":
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return self.fetch_flow_mapping_start()
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# Is it the flow sequence end indicator?
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if ch == "]":
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return self.fetch_flow_sequence_end()
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# Is it the flow mapping end indicator?
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if ch == "}":
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return self.fetch_flow_mapping_end()
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# Is it the flow entry indicator?
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if ch == ",":
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return self.fetch_flow_entry()
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# Is it the block entry indicator?
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if ch == "-" and self.check_block_entry():
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return self.fetch_block_entry()
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# Is it the key indicator?
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if ch == "?" and self.check_key():
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return self.fetch_key()
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# Is it the value indicator?
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if ch == ":" and self.check_value():
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return self.fetch_value()
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# Is it an alias?
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if ch == "*":
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return self.fetch_alias()
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# Is it an anchor?
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if ch == "&":
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return self.fetch_anchor()
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# Is it a tag?
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if ch == "!":
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return self.fetch_tag()
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# Is it a literal scalar?
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if ch == "|" and not self.flow_level:
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return self.fetch_literal()
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# Is it a folded scalar?
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if ch == ">" and not self.flow_level:
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return self.fetch_folded()
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# Is it a single quoted scalar?
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if ch == "'":
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return self.fetch_single()
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# Is it a double quoted scalar?
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if ch == '"':
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return self.fetch_double()
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# It must be a plain scalar then.
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if self.check_plain():
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return self.fetch_plain()
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# No? It's an error. Let's produce a nice error message.
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raise ScannerError(
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"while scanning for the next token",
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None,
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"found character %r that cannot start any token" % ch,
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self.get_mark(),
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)
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# Simple keys treatment.
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def next_possible_simple_key(self):
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# Return the number of the nearest possible simple key. Actually we
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# don't need to loop through the whole dictionary. We may replace it
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# with the following code:
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# if not self.possible_simple_keys:
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# return None
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# return self.possible_simple_keys[
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# min(self.possible_simple_keys.keys())].token_number
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min_token_number = None
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for level in self.possible_simple_keys:
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key = self.possible_simple_keys[level]
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if min_token_number is None or key.token_number < min_token_number:
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min_token_number = key.token_number
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return min_token_number
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def stale_possible_simple_keys(self):
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# Remove entries that are no longer possible simple keys. According to
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# the YAML specification, simple keys
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# - should be limited to a single line,
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# - should be no longer than 1024 characters.
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# Disabling this procedure will allow simple keys of any length and
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# height (may cause problems if indentation is broken though).
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for level in list(self.possible_simple_keys):
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key = self.possible_simple_keys[level]
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if key.line != self.line or self.index - key.index > 1024:
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if key.required:
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raise ScannerError(
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"while scanning a simple key",
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key.mark,
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"could not find expected ':'",
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self.get_mark(),
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)
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del self.possible_simple_keys[level]
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def save_possible_simple_key(self):
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# The next token may start a simple key. We check if it's possible
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# and save its position. This function is called for
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# ALIAS, ANCHOR, TAG, SCALAR(flow), '[', and '{'.
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# Check if a simple key is required at the current position.
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required = not self.flow_level and self.indent == self.column
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# The next token might be a simple key. Let's save it's number and
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# position.
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if self.allow_simple_key:
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self.remove_possible_simple_key()
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token_number = self.tokens_taken + len(self.tokens)
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key = SimpleKey(
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token_number,
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required,
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self.index,
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self.line,
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self.column,
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self.get_mark(),
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)
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self.possible_simple_keys[self.flow_level] = key
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def remove_possible_simple_key(self):
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# Remove the saved possible key position at the current flow level.
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if self.flow_level in self.possible_simple_keys:
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key = self.possible_simple_keys[self.flow_level]
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if key.required:
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raise ScannerError(
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"while scanning a simple key",
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key.mark,
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"could not find expected ':'",
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self.get_mark(),
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)
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del self.possible_simple_keys[self.flow_level]
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# Indentation functions.
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def unwind_indent(self, column):
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## In flow context, tokens should respect indentation.
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## Actually the condition should be `self.indent >= column` according to
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## the spec. But this condition will prohibit intuitively correct
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## constructions such as
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## key : {
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## }
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# if self.flow_level and self.indent > column:
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# raise ScannerError(None, None,
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# "invalid indentation or unclosed '[' or '{'",
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# self.get_mark())
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# In the flow context, indentation is ignored. We make the scanner less
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# restrictive then specification requires.
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if self.flow_level:
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return
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# In block context, we may need to issue the BLOCK-END tokens.
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while self.indent > column:
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mark = self.get_mark()
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self.indent = self.indents.pop()
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self.tokens.append(BlockEndToken(mark, mark))
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def add_indent(self, column):
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# Check if we need to increase indentation.
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if self.indent < column:
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self.indents.append(self.indent)
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self.indent = column
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return True
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return False
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# Fetchers.
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def fetch_stream_start(self):
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# We always add STREAM-START as the first token and STREAM-END as the
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# last token.
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# Read the token.
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mark = self.get_mark()
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# Add STREAM-START.
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self.tokens.append(StreamStartToken(mark, mark, encoding=self.encoding))
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def fetch_stream_end(self):
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# Set the current indentation to -1.
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self.unwind_indent(-1)
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# Reset simple keys.
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self.remove_possible_simple_key()
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self.allow_simple_key = False
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self.possible_simple_keys = {}
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# Read the token.
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mark = self.get_mark()
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# Add STREAM-END.
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self.tokens.append(StreamEndToken(mark, mark))
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# The steam is finished.
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self.done = True
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def fetch_directive(self):
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# Set the current indentation to -1.
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self.unwind_indent(-1)
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# Reset simple keys.
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self.remove_possible_simple_key()
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self.allow_simple_key = False
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# Scan and add DIRECTIVE.
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self.tokens.append(self.scan_directive())
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def fetch_document_start(self):
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self.fetch_document_indicator(DocumentStartToken)
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def fetch_document_end(self):
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self.fetch_document_indicator(DocumentEndToken)
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def fetch_document_indicator(self, TokenClass):
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# Set the current indentation to -1.
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self.unwind_indent(-1)
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# Reset simple keys. Note that there could not be a block collection
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# after '---'.
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self.remove_possible_simple_key()
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self.allow_simple_key = False
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# Add DOCUMENT-START or DOCUMENT-END.
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start_mark = self.get_mark()
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self.forward(3)
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end_mark = self.get_mark()
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self.tokens.append(TokenClass(start_mark, end_mark))
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def fetch_flow_sequence_start(self):
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self.fetch_flow_collection_start(FlowSequenceStartToken)
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def fetch_flow_mapping_start(self):
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self.fetch_flow_collection_start(FlowMappingStartToken)
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def fetch_flow_collection_start(self, TokenClass):
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# '[' and '{' may start a simple key.
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self.save_possible_simple_key()
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# Increase the flow level.
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self.flow_level += 1
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# Simple keys are allowed after '[' and '{'.
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self.allow_simple_key = True
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# Add FLOW-SEQUENCE-START or FLOW-MAPPING-START.
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start_mark = self.get_mark()
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self.forward()
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end_mark = self.get_mark()
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self.tokens.append(TokenClass(start_mark, end_mark))
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def fetch_flow_sequence_end(self):
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self.fetch_flow_collection_end(FlowSequenceEndToken)
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def fetch_flow_mapping_end(self):
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self.fetch_flow_collection_end(FlowMappingEndToken)
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def fetch_flow_collection_end(self, TokenClass):
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# Reset possible simple key on the current level.
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self.remove_possible_simple_key()
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# Decrease the flow level.
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self.flow_level -= 1
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# No simple keys after ']' or '}'.
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self.allow_simple_key = False
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# Add FLOW-SEQUENCE-END or FLOW-MAPPING-END.
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start_mark = self.get_mark()
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self.forward()
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end_mark = self.get_mark()
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self.tokens.append(TokenClass(start_mark, end_mark))
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def fetch_flow_entry(self):
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# Simple keys are allowed after ','.
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self.allow_simple_key = True
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# Reset possible simple key on the current level.
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self.remove_possible_simple_key()
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# Add FLOW-ENTRY.
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start_mark = self.get_mark()
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self.forward()
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end_mark = self.get_mark()
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self.tokens.append(FlowEntryToken(start_mark, end_mark))
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def fetch_block_entry(self):
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# Block context needs additional checks.
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if not self.flow_level:
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# Are we allowed to start a new entry?
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if not self.allow_simple_key:
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raise ScannerError(
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None, None, "sequence entries are not allowed here", self.get_mark()
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)
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# We may need to add BLOCK-SEQUENCE-START.
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if self.add_indent(self.column):
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mark = self.get_mark()
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self.tokens.append(BlockSequenceStartToken(mark, mark))
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# It's an error for the block entry to occur in the flow context,
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# but we let the parser detect this.
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else:
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pass
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# Simple keys are allowed after '-'.
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self.allow_simple_key = True
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|
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# Reset possible simple key on the current level.
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self.remove_possible_simple_key()
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# Add BLOCK-ENTRY.
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start_mark = self.get_mark()
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self.forward()
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end_mark = self.get_mark()
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self.tokens.append(BlockEntryToken(start_mark, end_mark))
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def fetch_key(self):
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# Block context needs additional checks.
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if not self.flow_level:
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# Are we allowed to start a key (not necessary a simple)?
|
|
if not self.allow_simple_key:
|
|
raise ScannerError(
|
|
None, None, "mapping keys are not allowed here", self.get_mark()
|
|
)
|
|
|
|
# We may need to add BLOCK-MAPPING-START.
|
|
if self.add_indent(self.column):
|
|
mark = self.get_mark()
|
|
self.tokens.append(BlockMappingStartToken(mark, mark))
|
|
|
|
# Simple keys are allowed after '?' in the block context.
|
|
self.allow_simple_key = not self.flow_level
|
|
|
|
# Reset possible simple key on the current level.
|
|
self.remove_possible_simple_key()
|
|
|
|
# Add KEY.
|
|
start_mark = self.get_mark()
|
|
self.forward()
|
|
end_mark = self.get_mark()
|
|
self.tokens.append(KeyToken(start_mark, end_mark))
|
|
|
|
def fetch_value(self):
|
|
|
|
# Do we determine a simple key?
|
|
if self.flow_level in self.possible_simple_keys:
|
|
|
|
# Add KEY.
|
|
key = self.possible_simple_keys[self.flow_level]
|
|
del self.possible_simple_keys[self.flow_level]
|
|
self.tokens.insert(
|
|
key.token_number - self.tokens_taken, KeyToken(key.mark, key.mark)
|
|
)
|
|
|
|
# If this key starts a new block mapping, we need to add
|
|
# BLOCK-MAPPING-START.
|
|
if not self.flow_level:
|
|
if self.add_indent(key.column):
|
|
self.tokens.insert(
|
|
key.token_number - self.tokens_taken,
|
|
BlockMappingStartToken(key.mark, key.mark),
|
|
)
|
|
|
|
# There cannot be two simple keys one after another.
|
|
self.allow_simple_key = False
|
|
|
|
# It must be a part of a complex key.
|
|
else:
|
|
|
|
# Block context needs additional checks.
|
|
# (Do we really need them? They will be caught by the parser
|
|
# anyway.)
|
|
if not self.flow_level:
|
|
|
|
# We are allowed to start a complex value if and only if
|
|
# we can start a simple key.
|
|
if not self.allow_simple_key:
|
|
raise ScannerError(
|
|
None,
|
|
None,
|
|
"mapping values are not allowed here",
|
|
self.get_mark(),
|
|
)
|
|
|
|
# If this value starts a new block mapping, we need to add
|
|
# BLOCK-MAPPING-START. It will be detected as an error later by
|
|
# the parser.
|
|
if not self.flow_level:
|
|
if self.add_indent(self.column):
|
|
mark = self.get_mark()
|
|
self.tokens.append(BlockMappingStartToken(mark, mark))
|
|
|
|
# Simple keys are allowed after ':' in the block context.
|
|
self.allow_simple_key = not self.flow_level
|
|
|
|
# Reset possible simple key on the current level.
|
|
self.remove_possible_simple_key()
|
|
|
|
# Add VALUE.
|
|
start_mark = self.get_mark()
|
|
self.forward()
|
|
end_mark = self.get_mark()
|
|
self.tokens.append(ValueToken(start_mark, end_mark))
|
|
|
|
def fetch_alias(self):
|
|
|
|
# ALIAS could be a simple key.
|
|
self.save_possible_simple_key()
|
|
|
|
# No simple keys after ALIAS.
|
|
self.allow_simple_key = False
|
|
|
|
# Scan and add ALIAS.
|
|
self.tokens.append(self.scan_anchor(AliasToken))
|
|
|
|
def fetch_anchor(self):
|
|
|
|
# ANCHOR could start a simple key.
|
|
self.save_possible_simple_key()
|
|
|
|
# No simple keys after ANCHOR.
|
|
self.allow_simple_key = False
|
|
|
|
# Scan and add ANCHOR.
|
|
self.tokens.append(self.scan_anchor(AnchorToken))
|
|
|
|
def fetch_tag(self):
|
|
|
|
# TAG could start a simple key.
|
|
self.save_possible_simple_key()
|
|
|
|
# No simple keys after TAG.
|
|
self.allow_simple_key = False
|
|
|
|
# Scan and add TAG.
|
|
self.tokens.append(self.scan_tag())
|
|
|
|
def fetch_literal(self):
|
|
self.fetch_block_scalar(style="|")
|
|
|
|
def fetch_folded(self):
|
|
self.fetch_block_scalar(style=">")
|
|
|
|
def fetch_block_scalar(self, style):
|
|
|
|
# A simple key may follow a block scalar.
|
|
self.allow_simple_key = True
|
|
|
|
# Reset possible simple key on the current level.
|
|
self.remove_possible_simple_key()
|
|
|
|
# Scan and add SCALAR.
|
|
self.tokens.append(self.scan_block_scalar(style))
|
|
|
|
def fetch_single(self):
|
|
self.fetch_flow_scalar(style="'")
|
|
|
|
def fetch_double(self):
|
|
self.fetch_flow_scalar(style='"')
|
|
|
|
def fetch_flow_scalar(self, style):
|
|
|
|
# A flow scalar could be a simple key.
|
|
self.save_possible_simple_key()
|
|
|
|
# No simple keys after flow scalars.
|
|
self.allow_simple_key = False
|
|
|
|
# Scan and add SCALAR.
|
|
self.tokens.append(self.scan_flow_scalar(style))
|
|
|
|
def fetch_plain(self):
|
|
|
|
# A plain scalar could be a simple key.
|
|
self.save_possible_simple_key()
|
|
|
|
# No simple keys after plain scalars. But note that `scan_plain` will
|
|
# change this flag if the scan is finished at the beginning of the
|
|
# line.
|
|
self.allow_simple_key = False
|
|
|
|
# Scan and add SCALAR. May change `allow_simple_key`.
|
|
self.tokens.append(self.scan_plain())
|
|
|
|
# Checkers.
|
|
|
|
def check_directive(self):
|
|
|
|
# DIRECTIVE: ^ '%' ...
|
|
# The '%' indicator is already checked.
|
|
if self.column == 0:
|
|
return True
|
|
|
|
def check_document_start(self):
|
|
|
|
# DOCUMENT-START: ^ '---' (' '|'\n')
|
|
if self.column == 0:
|
|
if self.prefix(3) == "---" and self.peek(3) in "\0 \t\r\n\x85\u2028\u2029":
|
|
return True
|
|
|
|
def check_document_end(self):
|
|
|
|
# DOCUMENT-END: ^ '...' (' '|'\n')
|
|
if self.column == 0:
|
|
if self.prefix(3) == "..." and self.peek(3) in "\0 \t\r\n\x85\u2028\u2029":
|
|
return True
|
|
|
|
def check_block_entry(self):
|
|
|
|
# BLOCK-ENTRY: '-' (' '|'\n')
|
|
return self.peek(1) in "\0 \t\r\n\x85\u2028\u2029"
|
|
|
|
def check_key(self):
|
|
|
|
# KEY(flow context): '?'
|
|
if self.flow_level:
|
|
return True
|
|
|
|
# KEY(block context): '?' (' '|'\n')
|
|
else:
|
|
return self.peek(1) in "\0 \t\r\n\x85\u2028\u2029"
|
|
|
|
def check_value(self):
|
|
|
|
# VALUE(flow context): ':'
|
|
if self.flow_level:
|
|
return True
|
|
|
|
# VALUE(block context): ':' (' '|'\n')
|
|
else:
|
|
return self.peek(1) in "\0 \t\r\n\x85\u2028\u2029"
|
|
|
|
def check_plain(self):
|
|
|
|
# A plain scalar may start with any non-space character except:
|
|
# '-', '?', ':', ',', '[', ']', '{', '}',
|
|
# '#', '&', '*', '!', '|', '>', '\'', '\"',
|
|
# '%', '@', '`'.
|
|
#
|
|
# It may also start with
|
|
# '-', '?', ':'
|
|
# if it is followed by a non-space character.
|
|
#
|
|
# Note that we limit the last rule to the block context (except the
|
|
# '-' character) because we want the flow context to be space
|
|
# independent.
|
|
ch = self.peek()
|
|
return ch not in "\0 \t\r\n\x85\u2028\u2029-?:,[]{}#&*!|>'\"%@`" or (
|
|
self.peek(1) not in "\0 \t\r\n\x85\u2028\u2029"
|
|
and (ch == "-" or (not self.flow_level and ch in "?:"))
|
|
)
|
|
|
|
# Scanners.
|
|
|
|
def scan_to_next_token(self):
|
|
# We ignore spaces, line breaks and comments.
|
|
# If we find a line break in the block context, we set the flag
|
|
# `allow_simple_key` on.
|
|
# The byte order mark is stripped if it's the first character in the
|
|
# stream. We do not yet support BOM inside the stream as the
|
|
# specification requires. Any such mark will be considered as a part
|
|
# of the document.
|
|
#
|
|
# TODO: We need to make tab handling rules more sane. A good rule is
|
|
# Tabs cannot precede tokens
|
|
# BLOCK-SEQUENCE-START, BLOCK-MAPPING-START, BLOCK-END,
|
|
# KEY(block), VALUE(block), BLOCK-ENTRY
|
|
# So the checking code is
|
|
# if <TAB>:
|
|
# self.allow_simple_keys = False
|
|
# We also need to add the check for `allow_simple_keys == True` to
|
|
# `unwind_indent` before issuing BLOCK-END.
|
|
# Scanners for block, flow, and plain scalars need to be modified.
|
|
|
|
if self.index == 0 and self.peek() == "\uFEFF":
|
|
self.forward()
|
|
found = False
|
|
while not found:
|
|
while self.peek() == " ":
|
|
self.forward()
|
|
if self.peek() == "#":
|
|
while self.peek() not in "\0\r\n\x85\u2028\u2029":
|
|
self.forward()
|
|
if self.scan_line_break():
|
|
if not self.flow_level:
|
|
self.allow_simple_key = True
|
|
else:
|
|
found = True
|
|
|
|
def scan_directive(self):
|
|
# See the specification for details.
|
|
start_mark = self.get_mark()
|
|
self.forward()
|
|
name = self.scan_directive_name(start_mark)
|
|
value = None
|
|
if name == "YAML":
|
|
value = self.scan_yaml_directive_value(start_mark)
|
|
end_mark = self.get_mark()
|
|
elif name == "TAG":
|
|
value = self.scan_tag_directive_value(start_mark)
|
|
end_mark = self.get_mark()
|
|
else:
|
|
end_mark = self.get_mark()
|
|
while self.peek() not in "\0\r\n\x85\u2028\u2029":
|
|
self.forward()
|
|
self.scan_directive_ignored_line(start_mark)
|
|
return DirectiveToken(name, value, start_mark, end_mark)
|
|
|
|
def scan_directive_name(self, start_mark):
|
|
# See the specification for details.
|
|
length = 0
|
|
ch = self.peek(length)
|
|
while "0" <= ch <= "9" or "A" <= ch <= "Z" or "a" <= ch <= "z" or ch in "-_":
|
|
length += 1
|
|
ch = self.peek(length)
|
|
if not length:
|
|
raise ScannerError(
|
|
"while scanning a directive",
|
|
start_mark,
|
|
"expected alphabetic or numeric character, but found %r" % ch,
|
|
self.get_mark(),
|
|
)
|
|
value = self.prefix(length)
|
|
self.forward(length)
|
|
ch = self.peek()
|
|
if ch not in "\0 \r\n\x85\u2028\u2029":
|
|
raise ScannerError(
|
|
"while scanning a directive",
|
|
start_mark,
|
|
"expected alphabetic or numeric character, but found %r" % ch,
|
|
self.get_mark(),
|
|
)
|
|
return value
|
|
|
|
def scan_yaml_directive_value(self, start_mark):
|
|
# See the specification for details.
|
|
while self.peek() == " ":
|
|
self.forward()
|
|
major = self.scan_yaml_directive_number(start_mark)
|
|
if self.peek() != ".":
|
|
raise ScannerError(
|
|
"while scanning a directive",
|
|
start_mark,
|
|
"expected a digit or '.', but found %r" % self.peek(),
|
|
self.get_mark(),
|
|
)
|
|
self.forward()
|
|
minor = self.scan_yaml_directive_number(start_mark)
|
|
if self.peek() not in "\0 \r\n\x85\u2028\u2029":
|
|
raise ScannerError(
|
|
"while scanning a directive",
|
|
start_mark,
|
|
"expected a digit or ' ', but found %r" % self.peek(),
|
|
self.get_mark(),
|
|
)
|
|
return (major, minor)
|
|
|
|
def scan_yaml_directive_number(self, start_mark):
|
|
# See the specification for details.
|
|
ch = self.peek()
|
|
if not ("0" <= ch <= "9"):
|
|
raise ScannerError(
|
|
"while scanning a directive",
|
|
start_mark,
|
|
"expected a digit, but found %r" % ch,
|
|
self.get_mark(),
|
|
)
|
|
length = 0
|
|
while "0" <= self.peek(length) <= "9":
|
|
length += 1
|
|
value = int(self.prefix(length))
|
|
self.forward(length)
|
|
return value
|
|
|
|
def scan_tag_directive_value(self, start_mark):
|
|
# See the specification for details.
|
|
while self.peek() == " ":
|
|
self.forward()
|
|
handle = self.scan_tag_directive_handle(start_mark)
|
|
while self.peek() == " ":
|
|
self.forward()
|
|
prefix = self.scan_tag_directive_prefix(start_mark)
|
|
return (handle, prefix)
|
|
|
|
def scan_tag_directive_handle(self, start_mark):
|
|
# See the specification for details.
|
|
value = self.scan_tag_handle("directive", start_mark)
|
|
ch = self.peek()
|
|
if ch != " ":
|
|
raise ScannerError(
|
|
"while scanning a directive",
|
|
start_mark,
|
|
"expected ' ', but found %r" % ch,
|
|
self.get_mark(),
|
|
)
|
|
return value
|
|
|
|
def scan_tag_directive_prefix(self, start_mark):
|
|
# See the specification for details.
|
|
value = self.scan_tag_uri("directive", start_mark)
|
|
ch = self.peek()
|
|
if ch not in "\0 \r\n\x85\u2028\u2029":
|
|
raise ScannerError(
|
|
"while scanning a directive",
|
|
start_mark,
|
|
"expected ' ', but found %r" % ch,
|
|
self.get_mark(),
|
|
)
|
|
return value
|
|
|
|
def scan_directive_ignored_line(self, start_mark):
|
|
# See the specification for details.
|
|
while self.peek() == " ":
|
|
self.forward()
|
|
if self.peek() == "#":
|
|
while self.peek() not in "\0\r\n\x85\u2028\u2029":
|
|
self.forward()
|
|
ch = self.peek()
|
|
if ch not in "\0\r\n\x85\u2028\u2029":
|
|
raise ScannerError(
|
|
"while scanning a directive",
|
|
start_mark,
|
|
"expected a comment or a line break, but found %r" % ch,
|
|
self.get_mark(),
|
|
)
|
|
self.scan_line_break()
|
|
|
|
def scan_anchor(self, TokenClass):
|
|
# The specification does not restrict characters for anchors and
|
|
# aliases. This may lead to problems, for instance, the document:
|
|
# [ *alias, value ]
|
|
# can be interpreted in two ways, as
|
|
# [ "value" ]
|
|
# and
|
|
# [ *alias , "value" ]
|
|
# Therefore we restrict aliases to numbers and ASCII letters.
|
|
start_mark = self.get_mark()
|
|
indicator = self.peek()
|
|
if indicator == "*":
|
|
name = "alias"
|
|
else:
|
|
name = "anchor"
|
|
self.forward()
|
|
length = 0
|
|
ch = self.peek(length)
|
|
while "0" <= ch <= "9" or "A" <= ch <= "Z" or "a" <= ch <= "z" or ch in "-_":
|
|
length += 1
|
|
ch = self.peek(length)
|
|
if not length:
|
|
raise ScannerError(
|
|
"while scanning an %s" % name,
|
|
start_mark,
|
|
"expected alphabetic or numeric character, but found %r" % ch,
|
|
self.get_mark(),
|
|
)
|
|
value = self.prefix(length)
|
|
self.forward(length)
|
|
ch = self.peek()
|
|
if ch not in "\0 \t\r\n\x85\u2028\u2029?:,]}%@`":
|
|
raise ScannerError(
|
|
"while scanning an %s" % name,
|
|
start_mark,
|
|
"expected alphabetic or numeric character, but found %r" % ch,
|
|
self.get_mark(),
|
|
)
|
|
end_mark = self.get_mark()
|
|
return TokenClass(value, start_mark, end_mark)
|
|
|
|
def scan_tag(self):
|
|
# See the specification for details.
|
|
start_mark = self.get_mark()
|
|
ch = self.peek(1)
|
|
if ch == "<":
|
|
handle = None
|
|
self.forward(2)
|
|
suffix = self.scan_tag_uri("tag", start_mark)
|
|
if self.peek() != ">":
|
|
raise ScannerError(
|
|
"while parsing a tag",
|
|
start_mark,
|
|
"expected '>', but found %r" % self.peek(),
|
|
self.get_mark(),
|
|
)
|
|
self.forward()
|
|
elif ch in "\0 \t\r\n\x85\u2028\u2029":
|
|
handle = None
|
|
suffix = "!"
|
|
self.forward()
|
|
else:
|
|
length = 1
|
|
use_handle = False
|
|
while ch not in "\0 \r\n\x85\u2028\u2029":
|
|
if ch == "!":
|
|
use_handle = True
|
|
break
|
|
length += 1
|
|
ch = self.peek(length)
|
|
handle = "!"
|
|
if use_handle:
|
|
handle = self.scan_tag_handle("tag", start_mark)
|
|
else:
|
|
handle = "!"
|
|
self.forward()
|
|
suffix = self.scan_tag_uri("tag", start_mark)
|
|
ch = self.peek()
|
|
if ch not in "\0 \r\n\x85\u2028\u2029":
|
|
raise ScannerError(
|
|
"while scanning a tag",
|
|
start_mark,
|
|
"expected ' ', but found %r" % ch,
|
|
self.get_mark(),
|
|
)
|
|
value = (handle, suffix)
|
|
end_mark = self.get_mark()
|
|
return TagToken(value, start_mark, end_mark)
|
|
|
|
def scan_block_scalar(self, style):
|
|
# See the specification for details.
|
|
|
|
if style == ">":
|
|
folded = True
|
|
else:
|
|
folded = False
|
|
|
|
chunks = []
|
|
start_mark = self.get_mark()
|
|
|
|
# Scan the header.
|
|
self.forward()
|
|
chomping, increment = self.scan_block_scalar_indicators(start_mark)
|
|
self.scan_block_scalar_ignored_line(start_mark)
|
|
|
|
# Determine the indentation level and go to the first non-empty line.
|
|
min_indent = self.indent + 1
|
|
if min_indent < 1:
|
|
min_indent = 1
|
|
if increment is None:
|
|
breaks, max_indent, end_mark = self.scan_block_scalar_indentation()
|
|
indent = max(min_indent, max_indent)
|
|
else:
|
|
indent = min_indent + increment - 1
|
|
breaks, end_mark = self.scan_block_scalar_breaks(indent)
|
|
line_break = ""
|
|
|
|
# Scan the inner part of the block scalar.
|
|
while self.column == indent and self.peek() != "\0":
|
|
chunks.extend(breaks)
|
|
leading_non_space = self.peek() not in " \t"
|
|
length = 0
|
|
while self.peek(length) not in "\0\r\n\x85\u2028\u2029":
|
|
length += 1
|
|
chunks.append(self.prefix(length))
|
|
self.forward(length)
|
|
line_break = self.scan_line_break()
|
|
breaks, end_mark = self.scan_block_scalar_breaks(indent)
|
|
if self.column == indent and self.peek() != "\0":
|
|
|
|
# Unfortunately, folding rules are ambiguous.
|
|
#
|
|
# This is the folding according to the specification:
|
|
|
|
if (
|
|
folded
|
|
and line_break == "\n"
|
|
and leading_non_space
|
|
and self.peek() not in " \t"
|
|
):
|
|
if not breaks:
|
|
chunks.append(" ")
|
|
else:
|
|
chunks.append(line_break)
|
|
|
|
# This is Clark Evans's interpretation (also in the spec
|
|
# examples):
|
|
#
|
|
# if folded and line_break == '\n':
|
|
# if not breaks:
|
|
# if self.peek() not in ' \t':
|
|
# chunks.append(' ')
|
|
# else:
|
|
# chunks.append(line_break)
|
|
# else:
|
|
# chunks.append(line_break)
|
|
else:
|
|
break
|
|
|
|
# Chomp the tail.
|
|
if chomping is not False:
|
|
chunks.append(line_break)
|
|
if chomping is True:
|
|
chunks.extend(breaks)
|
|
|
|
# We are done.
|
|
return ScalarToken("".join(chunks), False, start_mark, end_mark, style)
|
|
|
|
def scan_block_scalar_indicators(self, start_mark):
|
|
# See the specification for details.
|
|
chomping = None
|
|
increment = None
|
|
ch = self.peek()
|
|
if ch in "+-":
|
|
if ch == "+":
|
|
chomping = True
|
|
else:
|
|
chomping = False
|
|
self.forward()
|
|
ch = self.peek()
|
|
if ch in "0123456789":
|
|
increment = int(ch)
|
|
if increment == 0:
|
|
raise ScannerError(
|
|
"while scanning a block scalar",
|
|
start_mark,
|
|
"expected indentation indicator in the range 1-9, but found 0",
|
|
self.get_mark(),
|
|
)
|
|
self.forward()
|
|
elif ch in "0123456789":
|
|
increment = int(ch)
|
|
if increment == 0:
|
|
raise ScannerError(
|
|
"while scanning a block scalar",
|
|
start_mark,
|
|
"expected indentation indicator in the range 1-9, but found 0",
|
|
self.get_mark(),
|
|
)
|
|
self.forward()
|
|
ch = self.peek()
|
|
if ch in "+-":
|
|
if ch == "+":
|
|
chomping = True
|
|
else:
|
|
chomping = False
|
|
self.forward()
|
|
ch = self.peek()
|
|
if ch not in "\0 \r\n\x85\u2028\u2029":
|
|
raise ScannerError(
|
|
"while scanning a block scalar",
|
|
start_mark,
|
|
"expected chomping or indentation indicators, but found %r" % ch,
|
|
self.get_mark(),
|
|
)
|
|
return chomping, increment
|
|
|
|
def scan_block_scalar_ignored_line(self, start_mark):
|
|
# See the specification for details.
|
|
while self.peek() == " ":
|
|
self.forward()
|
|
if self.peek() == "#":
|
|
while self.peek() not in "\0\r\n\x85\u2028\u2029":
|
|
self.forward()
|
|
ch = self.peek()
|
|
if ch not in "\0\r\n\x85\u2028\u2029":
|
|
raise ScannerError(
|
|
"while scanning a block scalar",
|
|
start_mark,
|
|
"expected a comment or a line break, but found %r" % ch,
|
|
self.get_mark(),
|
|
)
|
|
self.scan_line_break()
|
|
|
|
def scan_block_scalar_indentation(self):
|
|
# See the specification for details.
|
|
chunks = []
|
|
max_indent = 0
|
|
end_mark = self.get_mark()
|
|
while self.peek() in " \r\n\x85\u2028\u2029":
|
|
if self.peek() != " ":
|
|
chunks.append(self.scan_line_break())
|
|
end_mark = self.get_mark()
|
|
else:
|
|
self.forward()
|
|
if self.column > max_indent:
|
|
max_indent = self.column
|
|
return chunks, max_indent, end_mark
|
|
|
|
def scan_block_scalar_breaks(self, indent):
|
|
# See the specification for details.
|
|
chunks = []
|
|
end_mark = self.get_mark()
|
|
while self.column < indent and self.peek() == " ":
|
|
self.forward()
|
|
while self.peek() in "\r\n\x85\u2028\u2029":
|
|
chunks.append(self.scan_line_break())
|
|
end_mark = self.get_mark()
|
|
while self.column < indent and self.peek() == " ":
|
|
self.forward()
|
|
return chunks, end_mark
|
|
|
|
def scan_flow_scalar(self, style):
|
|
# See the specification for details.
|
|
# Note that we loose indentation rules for quoted scalars. Quoted
|
|
# scalars don't need to adhere indentation because " and ' clearly
|
|
# mark the beginning and the end of them. Therefore we are less
|
|
# restrictive then the specification requires. We only need to check
|
|
# that document separators are not included in scalars.
|
|
if style == '"':
|
|
double = True
|
|
else:
|
|
double = False
|
|
chunks = []
|
|
start_mark = self.get_mark()
|
|
quote = self.peek()
|
|
self.forward()
|
|
chunks.extend(self.scan_flow_scalar_non_spaces(double, start_mark))
|
|
while self.peek() != quote:
|
|
chunks.extend(self.scan_flow_scalar_spaces(double, start_mark))
|
|
chunks.extend(self.scan_flow_scalar_non_spaces(double, start_mark))
|
|
self.forward()
|
|
end_mark = self.get_mark()
|
|
return ScalarToken("".join(chunks), False, start_mark, end_mark, style)
|
|
|
|
ESCAPE_REPLACEMENTS = {
|
|
"0": "\0",
|
|
"a": "\x07",
|
|
"b": "\x08",
|
|
"t": "\x09",
|
|
"\t": "\x09",
|
|
"n": "\x0A",
|
|
"v": "\x0B",
|
|
"f": "\x0C",
|
|
"r": "\x0D",
|
|
"e": "\x1B",
|
|
" ": "\x20",
|
|
'"': '"',
|
|
"\\": "\\",
|
|
"/": "/",
|
|
"N": "\x85",
|
|
"_": "\xA0",
|
|
"L": "\u2028",
|
|
"P": "\u2029",
|
|
}
|
|
|
|
ESCAPE_CODES = {
|
|
"x": 2,
|
|
"u": 4,
|
|
"U": 8,
|
|
}
|
|
|
|
def scan_flow_scalar_non_spaces(self, double, start_mark):
|
|
# See the specification for details.
|
|
chunks = []
|
|
while True:
|
|
length = 0
|
|
while self.peek(length) not in "'\"\\\0 \t\r\n\x85\u2028\u2029":
|
|
length += 1
|
|
if length:
|
|
chunks.append(self.prefix(length))
|
|
self.forward(length)
|
|
ch = self.peek()
|
|
if not double and ch == "'" and self.peek(1) == "'":
|
|
chunks.append("'")
|
|
self.forward(2)
|
|
elif (double and ch == "'") or (not double and ch in '"\\'):
|
|
chunks.append(ch)
|
|
self.forward()
|
|
elif double and ch == "\\":
|
|
self.forward()
|
|
ch = self.peek()
|
|
if ch in self.ESCAPE_REPLACEMENTS:
|
|
chunks.append(self.ESCAPE_REPLACEMENTS[ch])
|
|
self.forward()
|
|
elif ch in self.ESCAPE_CODES:
|
|
length = self.ESCAPE_CODES[ch]
|
|
self.forward()
|
|
for k in range(length):
|
|
if self.peek(k) not in "0123456789ABCDEFabcdef":
|
|
raise ScannerError(
|
|
"while scanning a double-quoted scalar",
|
|
start_mark,
|
|
"expected escape sequence of %d hexadecimal numbers, but found %r"
|
|
% (length, self.peek(k)),
|
|
self.get_mark(),
|
|
)
|
|
code = int(self.prefix(length), 16)
|
|
chunks.append(chr(code))
|
|
self.forward(length)
|
|
elif ch in "\r\n\x85\u2028\u2029":
|
|
self.scan_line_break()
|
|
chunks.extend(self.scan_flow_scalar_breaks(double, start_mark))
|
|
else:
|
|
raise ScannerError(
|
|
"while scanning a double-quoted scalar",
|
|
start_mark,
|
|
"found unknown escape character %r" % ch,
|
|
self.get_mark(),
|
|
)
|
|
else:
|
|
return chunks
|
|
|
|
def scan_flow_scalar_spaces(self, double, start_mark):
|
|
# See the specification for details.
|
|
chunks = []
|
|
length = 0
|
|
while self.peek(length) in " \t":
|
|
length += 1
|
|
whitespaces = self.prefix(length)
|
|
self.forward(length)
|
|
ch = self.peek()
|
|
if ch == "\0":
|
|
raise ScannerError(
|
|
"while scanning a quoted scalar",
|
|
start_mark,
|
|
"found unexpected end of stream",
|
|
self.get_mark(),
|
|
)
|
|
elif ch in "\r\n\x85\u2028\u2029":
|
|
line_break = self.scan_line_break()
|
|
breaks = self.scan_flow_scalar_breaks(double, start_mark)
|
|
if line_break != "\n":
|
|
chunks.append(line_break)
|
|
elif not breaks:
|
|
chunks.append(" ")
|
|
chunks.extend(breaks)
|
|
else:
|
|
chunks.append(whitespaces)
|
|
return chunks
|
|
|
|
def scan_flow_scalar_breaks(self, double, start_mark):
|
|
# See the specification for details.
|
|
chunks = []
|
|
while True:
|
|
# Instead of checking indentation, we check for document
|
|
# separators.
|
|
prefix = self.prefix(3)
|
|
if (prefix == "---" or prefix == "...") and self.peek(
|
|
3
|
|
) in "\0 \t\r\n\x85\u2028\u2029":
|
|
raise ScannerError(
|
|
"while scanning a quoted scalar",
|
|
start_mark,
|
|
"found unexpected document separator",
|
|
self.get_mark(),
|
|
)
|
|
while self.peek() in " \t":
|
|
self.forward()
|
|
if self.peek() in "\r\n\x85\u2028\u2029":
|
|
chunks.append(self.scan_line_break())
|
|
else:
|
|
return chunks
|
|
|
|
def scan_plain(self):
|
|
# See the specification for details.
|
|
# We add an additional restriction for the flow context:
|
|
# plain scalars in the flow context cannot contain ',' or '?'.
|
|
# We also keep track of the `allow_simple_key` flag here.
|
|
# Indentation rules are loosed for the flow context.
|
|
chunks = []
|
|
start_mark = self.get_mark()
|
|
end_mark = start_mark
|
|
indent = self.indent + 1
|
|
# We allow zero indentation for scalars, but then we need to check for
|
|
# document separators at the beginning of the line.
|
|
# if indent == 0:
|
|
# indent = 1
|
|
spaces = []
|
|
while True:
|
|
length = 0
|
|
if self.peek() == "#":
|
|
break
|
|
while True:
|
|
ch = self.peek(length)
|
|
if (
|
|
ch in "\0 \t\r\n\x85\u2028\u2029"
|
|
or (
|
|
ch == ":"
|
|
and self.peek(length + 1)
|
|
in "\0 \t\r\n\x85\u2028\u2029"
|
|
+ (",[]{}" if self.flow_level else "")
|
|
)
|
|
or (self.flow_level and ch in ",?[]{}")
|
|
):
|
|
break
|
|
length += 1
|
|
if length == 0:
|
|
break
|
|
self.allow_simple_key = False
|
|
chunks.extend(spaces)
|
|
chunks.append(self.prefix(length))
|
|
self.forward(length)
|
|
end_mark = self.get_mark()
|
|
spaces = self.scan_plain_spaces(indent, start_mark)
|
|
if (
|
|
not spaces
|
|
or self.peek() == "#"
|
|
or (not self.flow_level and self.column < indent)
|
|
):
|
|
break
|
|
return ScalarToken("".join(chunks), True, start_mark, end_mark)
|
|
|
|
def scan_plain_spaces(self, indent, start_mark):
|
|
# See the specification for details.
|
|
# The specification is really confusing about tabs in plain scalars.
|
|
# We just forbid them completely. Do not use tabs in YAML!
|
|
chunks = []
|
|
length = 0
|
|
while self.peek(length) in " ":
|
|
length += 1
|
|
whitespaces = self.prefix(length)
|
|
self.forward(length)
|
|
ch = self.peek()
|
|
if ch in "\r\n\x85\u2028\u2029":
|
|
line_break = self.scan_line_break()
|
|
self.allow_simple_key = True
|
|
prefix = self.prefix(3)
|
|
if (prefix == "---" or prefix == "...") and self.peek(
|
|
3
|
|
) in "\0 \t\r\n\x85\u2028\u2029":
|
|
return
|
|
breaks = []
|
|
while self.peek() in " \r\n\x85\u2028\u2029":
|
|
if self.peek() == " ":
|
|
self.forward()
|
|
else:
|
|
breaks.append(self.scan_line_break())
|
|
prefix = self.prefix(3)
|
|
if (prefix == "---" or prefix == "...") and self.peek(
|
|
3
|
|
) in "\0 \t\r\n\x85\u2028\u2029":
|
|
return
|
|
if line_break != "\n":
|
|
chunks.append(line_break)
|
|
elif not breaks:
|
|
chunks.append(" ")
|
|
chunks.extend(breaks)
|
|
elif whitespaces:
|
|
chunks.append(whitespaces)
|
|
return chunks
|
|
|
|
def scan_tag_handle(self, name, start_mark):
|
|
# See the specification for details.
|
|
# For some strange reasons, the specification does not allow '_' in
|
|
# tag handles. I have allowed it anyway.
|
|
ch = self.peek()
|
|
if ch != "!":
|
|
raise ScannerError(
|
|
"while scanning a %s" % name,
|
|
start_mark,
|
|
"expected '!', but found %r" % ch,
|
|
self.get_mark(),
|
|
)
|
|
length = 1
|
|
ch = self.peek(length)
|
|
if ch != " ":
|
|
while (
|
|
"0" <= ch <= "9" or "A" <= ch <= "Z" or "a" <= ch <= "z" or ch in "-_"
|
|
):
|
|
length += 1
|
|
ch = self.peek(length)
|
|
if ch != "!":
|
|
self.forward(length)
|
|
raise ScannerError(
|
|
"while scanning a %s" % name,
|
|
start_mark,
|
|
"expected '!', but found %r" % ch,
|
|
self.get_mark(),
|
|
)
|
|
length += 1
|
|
value = self.prefix(length)
|
|
self.forward(length)
|
|
return value
|
|
|
|
def scan_tag_uri(self, name, start_mark):
|
|
# See the specification for details.
|
|
# Note: we do not check if URI is well-formed.
|
|
chunks = []
|
|
length = 0
|
|
ch = self.peek(length)
|
|
while (
|
|
"0" <= ch <= "9"
|
|
or "A" <= ch <= "Z"
|
|
or "a" <= ch <= "z"
|
|
or ch in "-;/?:@&=+$,_.!~*'()[]%"
|
|
):
|
|
if ch == "%":
|
|
chunks.append(self.prefix(length))
|
|
self.forward(length)
|
|
length = 0
|
|
chunks.append(self.scan_uri_escapes(name, start_mark))
|
|
else:
|
|
length += 1
|
|
ch = self.peek(length)
|
|
if length:
|
|
chunks.append(self.prefix(length))
|
|
self.forward(length)
|
|
length = 0
|
|
if not chunks:
|
|
raise ScannerError(
|
|
"while parsing a %s" % name,
|
|
start_mark,
|
|
"expected URI, but found %r" % ch,
|
|
self.get_mark(),
|
|
)
|
|
return "".join(chunks)
|
|
|
|
def scan_uri_escapes(self, name, start_mark):
|
|
# See the specification for details.
|
|
codes = []
|
|
mark = self.get_mark()
|
|
while self.peek() == "%":
|
|
self.forward()
|
|
for k in range(2):
|
|
if self.peek(k) not in "0123456789ABCDEFabcdef":
|
|
raise ScannerError(
|
|
"while scanning a %s" % name,
|
|
start_mark,
|
|
"expected URI escape sequence of 2 hexadecimal numbers, but found %r"
|
|
% self.peek(k),
|
|
self.get_mark(),
|
|
)
|
|
codes.append(int(self.prefix(2), 16))
|
|
self.forward(2)
|
|
try:
|
|
value = bytes(codes).decode("utf-8")
|
|
except UnicodeDecodeError as exc:
|
|
raise ScannerError("while scanning a %s" % name, start_mark, str(exc), mark)
|
|
return value
|
|
|
|
def scan_line_break(self):
|
|
# Transforms:
|
|
# '\r\n' : '\n'
|
|
# '\r' : '\n'
|
|
# '\n' : '\n'
|
|
# '\x85' : '\n'
|
|
# '\u2028' : '\u2028'
|
|
# '\u2029 : '\u2029'
|
|
# default : ''
|
|
ch = self.peek()
|
|
if ch in "\r\n\x85":
|
|
if self.prefix(2) == "\r\n":
|
|
self.forward(2)
|
|
else:
|
|
self.forward()
|
|
return "\n"
|
|
elif ch in "\u2028\u2029":
|
|
self.forward()
|
|
return ch
|
|
return ""
|