# (C) Copyright 2005-2023 Enthought, Inc., Austin, TX # All rights reserved. # # This software is provided without warranty under the terms of the BSD # license included in LICENSE.txt and may be redistributed only under # the conditions described in the aforementioned license. The license # is also available online at http://www.enthought.com/licenses/BSD.txt # # Thanks for using Enthought open source! from pyface.qt import QtGui from pygments.lexer import RegexLexer, _TokenType, Text, Error from pygments.lexers import CLexer, CppLexer, PythonLexer, get_lexer_by_name from pygments.styles.default import DefaultStyle from pygments.token import Comment def get_tokens_unprocessed(self, text, stack=("root",)): """ Split ``text`` into (tokentype, text) pairs. Monkeypatched to store the final stack on the object itself. The `text` parameter that gets passed is only the current line, so to highlight things like multiline strings correctly, we need to retrieve the state from the previous line (this is done in PygmentsHighlighter, below), and use it to continue processing the current line. """ pos = 0 tokendefs = self._tokens if hasattr(self, "_saved_state_stack"): statestack = list(self._saved_state_stack) else: statestack = list(stack) statetokens = tokendefs[statestack[-1]] while 1: for rexmatch, action, new_state in statetokens: m = rexmatch(text, pos) if m: if action is not None: if type(action) is _TokenType: yield pos, action, m.group() else: for item in action(self, m): yield item pos = m.end() if new_state is not None: # state transition if isinstance(new_state, tuple): for state in new_state: if state == "#pop": statestack.pop() elif state == "#push": statestack.append(statestack[-1]) else: statestack.append(state) elif isinstance(new_state, int): # pop del statestack[new_state:] elif new_state == "#push": statestack.append(statestack[-1]) else: assert False, "wrong state def: %r" % new_state statetokens = tokendefs[statestack[-1]] break else: try: if text[pos] == "\n": # at EOL, reset state to "root" pos += 1 statestack = ["root"] statetokens = tokendefs["root"] yield pos, Text, "\n" continue yield pos, Error, text[pos] pos += 1 except IndexError: break self._saved_state_stack = list(statestack) # Monkeypatch! RegexLexer.get_tokens_unprocessed = get_tokens_unprocessed # Even with the above monkey patch to store state, multiline comments do not # work since they are stateless (Pygments uses a single multiline regex for # these comments, but Qt lexes by line). So we need to add a state for comments # to the C and C++ lexers. This means that nested multiline comments will appear # to be valid C/C++, but this is better than the alternative for now. def replace_pattern(tokens, new_pattern): """ Given a RegexLexer token dictionary 'tokens', replace all patterns that match the token specified in 'new_pattern' with 'new_pattern'. """ for state in tokens.values(): for index, pattern in enumerate(state): if isinstance(pattern, tuple) and pattern[1] == new_pattern[1]: state[index] = new_pattern # More monkeypatching! comment_start = (r"/\*", Comment.Multiline, "comment") comment_state = [ (r"[^*/]", Comment.Multiline), (r"/\*", Comment.Multiline, "#push"), (r"\*/", Comment.Multiline, "#pop"), (r"[*/]", Comment.Multiline), ] replace_pattern(CLexer.tokens, comment_start) replace_pattern(CppLexer.tokens, comment_start) CLexer.tokens["comment"] = comment_state CppLexer.tokens["comment"] = comment_state class BlockUserData(QtGui.QTextBlockUserData): """ Storage for the user data associated with each line. """ syntax_stack = ("root",) def __init__(self, **kwds): QtGui.QTextBlockUserData.__init__(self) for key, value in kwds.items(): setattr(self, key, value) def __repr__(self): attrs = ["syntax_stack"] kwds = ", ".join( ["%s=%r" % (attr, getattr(self, attr)) for attr in attrs] ) return "BlockUserData(%s)" % kwds class PygmentsHighlighter(QtGui.QSyntaxHighlighter): """ Syntax highlighter that uses Pygments for parsing. """ def __init__(self, parent, lexer=None): super().__init__(parent) try: self._lexer = get_lexer_by_name(lexer) except: self._lexer = PythonLexer() self._style = DefaultStyle # Caches for formats and brushes. self._brushes = {} self._formats = {} def highlightBlock(self, qstring): """ Highlight a block of text. """ qstring = str(qstring) prev_data = self.previous_block_data() if prev_data is not None: self._lexer._saved_state_stack = prev_data.syntax_stack elif hasattr(self._lexer, "_saved_state_stack"): del self._lexer._saved_state_stack index = 0 # Lex the text using Pygments for token, text in self._lexer.get_tokens(qstring): l = len(text) format = self._get_format(token) if format is not None: self.setFormat(index, l, format) index += l if hasattr(self._lexer, "_saved_state_stack"): data = BlockUserData(syntax_stack=self._lexer._saved_state_stack) self.currentBlock().setUserData(data) # there is a bug in pyside and it will crash unless we # hold on to the reference a little longer data = self.currentBlock().userData() # Clean up for the next go-round. del self._lexer._saved_state_stack def previous_block_data(self): """ Convenience method for returning the previous block's user data. """ return self.currentBlock().previous().userData() def _get_format(self, token): """ Returns a QTextCharFormat for token or None. """ if token in self._formats: return self._formats[token] result = None while not self._style.styles_token(token): token = token.parent for key, value in self._style.style_for_token(token).items(): if value: if result is None: result = QtGui.QTextCharFormat() if key == "color": result.setForeground(self._get_brush(value)) elif key == "bgcolor": result.setBackground(self._get_brush(value)) elif key == "bold": result.setFontWeight(QtGui.QFont.Weight.Bold) elif key == "italic": result.setFontItalic(True) elif key == "underline": result.setUnderlineStyle( QtGui.QTextCharFormat.UnderlineStyle.SingleUnderline ) elif key == "sans": result.setFontStyleHint(QtGui.QFont.SansSerif) elif key == "roman": result.setFontStyleHint(QtGui.QFont.StyleHint.Times) elif key == "mono": result.setFontStyleHint(QtGui.QFont.TypeWriter) elif key == "border": # Borders are normally used for errors. We can't do a border # so instead we do a wavy underline result.setUnderlineStyle( QtGui.QTextCharFormat.UnderlineStyle.WaveUnderline ) result.setUnderlineColor(self._get_color(value)) self._formats[token] = result return result def _get_brush(self, color): """ Returns a brush for the color. """ result = self._brushes.get(color) if result is None: qcolor = self._get_color(color) result = QtGui.QBrush(qcolor) self._brushes[color] = result return result def _get_color(self, color): qcolor = QtGui.QColor() qcolor.setRgb( int(color[:2], base=16), int(color[2:4], base=16), int(color[4:6], base=16), ) return qcolor