93 lines
3.3 KiB
Python
93 lines
3.3 KiB
Python
|
"""
|
||
|
|
`GrammarLexer` is compatible with other lexers and can be used to highlight
|
||
|
|
the input using a regular grammar with annotations.
|
||
|
|
"""
|
||
|
|
from typing import Callable, Dict, Optional
|
||
|
|
|
||
|
|
from prompt_toolkit.document import Document
|
||
|
|
from prompt_toolkit.formatted_text.base import StyleAndTextTuples
|
||
|
|
from prompt_toolkit.formatted_text.utils import split_lines
|
||
|
|
from prompt_toolkit.lexers import Lexer
|
||
|
|
|
||
|
|
from .compiler import _CompiledGrammar
|
||
|
|
|
||
|
|
__all__ = [
|
||
|
|
"GrammarLexer",
|
||
|
|
]
|
||
|
|
|
||
|
|
|
||
|
|
class GrammarLexer(Lexer):
|
||
|
|
"""
|
||
|
|
Lexer which can be used for highlighting of fragments according to variables in the grammar.
|
||
|
|
|
||
|
|
(It does not actual lexing of the string, but it exposes an API, compatible
|
||
|
|
with the Pygments lexer class.)
|
||
|
|
|
||
|
|
:param compiled_grammar: Grammar as returned by the `compile()` function.
|
||
|
|
:param lexers: Dictionary mapping variable names of the regular grammar to
|
||
|
|
the lexers that should be used for this part. (This can
|
||
|
|
call other lexers recursively.) If you wish a part of the
|
||
|
|
grammar to just get one fragment, use a
|
||
|
|
`prompt_toolkit.lexers.SimpleLexer`.
|
||
|
|
"""
|
||
|
|
|
||
|
|
def __init__(
|
||
|
|
self,
|
||
|
|
compiled_grammar: _CompiledGrammar,
|
||
|
|
default_style: str = "",
|
||
|
|
lexers: Optional[Dict[str, Lexer]] = None,
|
||
|
|
) -> None:
|
||
|
|
|
||
|
|
self.compiled_grammar = compiled_grammar
|
||
|
|
self.default_style = default_style
|
||
|
|
self.lexers = lexers or {}
|
||
|
|
|
||
|
|
def _get_text_fragments(self, text: str) -> StyleAndTextTuples:
|
||
|
|
m = self.compiled_grammar.match_prefix(text)
|
||
|
|
|
||
|
|
if m:
|
||
|
|
characters: StyleAndTextTuples = [(self.default_style, c) for c in text]
|
||
|
|
|
||
|
|
for v in m.variables():
|
||
|
|
# If we have a `Lexer` instance for this part of the input.
|
||
|
|
# Tokenize recursively and apply tokens.
|
||
|
|
lexer = self.lexers.get(v.varname)
|
||
|
|
|
||
|
|
if lexer:
|
||
|
|
document = Document(text[v.start : v.stop])
|
||
|
|
lexer_tokens_for_line = lexer.lex_document(document)
|
||
|
|
text_fragments: StyleAndTextTuples = []
|
||
|
|
for i in range(len(document.lines)):
|
||
|
|
text_fragments.extend(lexer_tokens_for_line(i))
|
||
|
|
text_fragments.append(("", "\n"))
|
||
|
|
if text_fragments:
|
||
|
|
text_fragments.pop()
|
||
|
|
|
||
|
|
i = v.start
|
||
|
|
for t, s, *_ in text_fragments:
|
||
|
|
for c in s:
|
||
|
|
if characters[i][0] == self.default_style:
|
||
|
|
characters[i] = (t, characters[i][1])
|
||
|
|
i += 1
|
||
|
|
|
||
|
|
# Highlight trailing input.
|
||
|
|
trailing_input = m.trailing_input()
|
||
|
|
if trailing_input:
|
||
|
|
for i in range(trailing_input.start, trailing_input.stop):
|
||
|
|
characters[i] = ("class:trailing-input", characters[i][1])
|
||
|
|
|
||
|
|
return characters
|
||
|
|
else:
|
||
|
|
return [("", text)]
|
||
|
|
|
||
|
|
def lex_document(self, document: Document) -> Callable[[int], StyleAndTextTuples]:
|
||
|
|
lines = list(split_lines(self._get_text_fragments(document.text)))
|
||
|
|
|
||
|
|
def get_line(lineno: int) -> StyleAndTextTuples:
|
||
|
|
try:
|
||
|
|
return lines[lineno]
|
||
|
|
except IndexError:
|
||
|
|
return []
|
||
|
|
|
||
|
|
return get_line
|