# CodeEditor based on QT example, Python syntax highlighter found on Python site from ..Qt import QtGui, QtCore, QtWidgets def _make_textformats(color, style=''): """Return a QTextCharFormat with the given attributes. """ _color = QtGui.QColor() _color.setNamedColor(color) _format = QtGui.QTextCharFormat() _format.setForeground(_color) if 'bold' in style: _format.setFontWeight(QtGui.QFont.Bold) if 'italic' in style: _format.setFontItalic(True) return _format # Syntax styles that can be shared by all languages STYLES = { 'keyword': _make_textformats('blue'), 'operator': _make_textformats('black'), 'brace': _make_textformats('black'), 'defclass': _make_textformats('black', 'bold'), 'string': _make_textformats('darkGreen'), 'comment': _make_textformats('gray', 'italic'), 'self': _make_textformats('brown', 'italic'), 'property': _make_textformats('brown'), 'numbers': _make_textformats('darkRed'), } class PythonHighlighter(QtGui.QSyntaxHighlighter): """ Syntax highlighter for the Python language. """ # Python keywords keywords = [ 'and', 'assert', 'break', 'class', 'continue', 'def', 'del', 'elif', 'else', 'except', 'exec', 'finally', 'for', 'from', 'global', 'if', 'import', 'in', 'is', 'lambda', 'not', 'or', 'pass', 'print', 'raise', 'return', 'try', 'while', 'yield', 'None', 'True', 'False', 'object' ] def __init__(self, document): super().__init__(document) # Multi-line strings (expression, flag, style) # FIXME: The triple-quotes in these two lines will mess up the # syntax highlighting from this point onward self.tri_single = (QtCore.QRegExp("r'{3}"), 1, STYLES['string']) self.tri_double = (QtCore.QRegExp('r?"{3}'), 2, STYLES['string']) rules = [] # Keyword, operator, and brace rules rules += [(rf'\b{w}\b', 0, STYLES['keyword']) for w in PythonHighlighter.keywords] # Other rules rules += [ # 'self' (r'\bself\b', 0, STYLES['self']), # 'def' followed by an identifier (r'\bdef\b\s*(\w+)', 1, STYLES['defclass']), # 'class' followed by an identifier (r'\bclass\b\s*(\w+)', 1, STYLES['defclass']), # @ followed by a word (r'\s*@(\w+)\s*', 0, STYLES['property']), # Numeric literals (r'\b[+-]?\d+[lL]?\b', 0, STYLES['numbers']), (r'\b[+-]?0[xX][\dA-Fa-f]+[lL]?\b', 0, STYLES['numbers']), (r'\b[+-]?\d+(?:\.\d+)?(?:[eE][+-]?\d+)?\b', 0, STYLES['numbers']), # Double-quoted string, possibly containing escape sequences (r'[rf]?"[^"\\]*(\\.[^"\\]*)*"', 0, STYLES['string']), # Single-quoted string, possibly containing escape sequences (r"[rf]?'[^'\\]*(\\.[^'\\]*)*'", 0, STYLES['string']), # From '#' until a newline (r'#[^\n]*', 0, STYLES['comment']), ] # Build a QRegExp for each pattern self.rules = [(QtCore.QRegExp(pat), index, fmt) for (pat, index, fmt) in rules] def highlightBlock(self, text): """ Apply syntax highlighting to the given block of text. """ # Do other syntax formatting for expression, nth, rule in self.rules: index = expression.indexIn(text, 0) while index >= 0: # We actually want the index of the nth match index = expression.pos(nth) length = len(expression.cap(nth)) self.setFormat(index, length, rule) index = expression.indexIn(text, index + length) self.setCurrentBlockState(0) # Do multi-line strings in_multiline = self.match_multiline(text, *self.tri_single) if not in_multiline: in_multiline = self.match_multiline(text, *self.tri_double) def match_multiline(self, text, delimiter, in_state, style): """ Highlighting of multi-line strings. ``delimiter`` should be a ``QRegExp`` for triple-single-quotes or triple-double-quotes, and ``in_state`` should be a unique integer to represent the corresponding state changes when inside those strings. Returns True if we're still inside a multi-line string when this function is finished. """ # If inside triple-single quotes, start at 0 if self.previousBlockState() == in_state: start = 0 add = 0 # Otherwise, look for the delimiter on this line else: start = delimiter.indexIn(text) # Move past this match add = delimiter.matchedLength() # As long as there's a delimiter match on this line... while start >= 0: # Look for the ending delimiter end = delimiter.indexIn(text, start + add) # Ending delimiter on this line? if end >= add: length = end - start + add + delimiter.matchedLength() self.setCurrentBlockState(0) # No; multi-line string else: self.setCurrentBlockState(in_state) try: length = text.length() - start + add except AttributeError: length = len(text) - start + add # Apply formatting self.setFormat(start, length, style) # Look for the next match start = delimiter.indexIn(text, start + length) # Return True if still inside a multi-line string, False otherwise if self.currentBlockState() == in_state: return True else: return False class LineNumbers(QtWidgets.QWidget): def __init__(self, editor): super().__init__(editor) self.editor = editor def sizeHint(self): return QtCore.QSize(self.editor.width_linenumber, 0) def paintEvent(self, event): self.editor.paintevent_linenumber(event) class CodeEditor(QtWidgets.QPlainTextEdit): # more or less a direct translation of the Qt example def __init__(self, parent): super().__init__(parent) self.current_linenumber = LineNumbers(self) self.blockCountChanged.connect(self.update_width_linenumber) self.updateRequest.connect(self.update_current_area) self.cursorPositionChanged.connect(self.highlight_current_line) self.update_width_linenumber(0) self.highlight = PythonHighlighter(self.document()) def keyPressEvent(self, evt): if evt.key() == QtCore.Qt.Key_Tab: # use spaces instead of tab self.insertPlainText(' '*4) elif evt.key() == QtCore.Qt.Key_Insert: self.setOverwriteMode(not self.overwriteMode()) else: super().keyPressEvent(evt) @property def width_linenumber(self): digits = 1 count = max(1, self.blockCount()) while count >= 10: count /= 10 digits += 1 space = 6 + self.fontMetrics().width('9') * digits return space def update_width_linenumber(self, _): self.setViewportMargins(self.width_linenumber, 0, 0, 0) def update_current_area(self, rect, dy): if dy: self.current_linenumber.scroll(0, dy) else: self.current_linenumber.update(0, rect.y(), self.current_linenumber.width(), rect.height()) if rect.contains(self.viewport().rect()): self.update_width_linenumber(0) def resizeEvent(self, evt): super().resizeEvent(evt) cr = self.contentsRect() self.current_linenumber.setGeometry(QtCore.QRect(cr.left(), cr.top(), self.width_linenumber, cr.height())) def paintevent_linenumber(self, evt): painter = QtGui.QPainter(self.current_linenumber) painter.fillRect(evt.rect(), QtCore.Qt.lightGray) block = self.firstVisibleBlock() block_number = block.blockNumber() top = self.blockBoundingGeometry(block).translated(self.contentOffset()).top() bottom = top + self.blockBoundingRect(block).height() # Just to make sure I use the right font height = self.fontMetrics().height() while block.isValid() and (top <= evt.rect().bottom()): if block.isVisible() and (bottom >= evt.rect().top()): number = str(block_number + 1) painter.setPen(QtCore.Qt.black) painter.drawText(0, top, self.current_linenumber.width() - 3, height, QtCore.Qt.AlignRight, number) block = block.next() top = bottom bottom = top + self.blockBoundingRect(block).height() block_number += 1 def highlight_current_line(self): extra_selections = [] if not self.isReadOnly(): selection = QtWidgets.QTextEdit.ExtraSelection() line_color = QtGui.QColor(QtCore.Qt.yellow).lighter(180) selection.format.setBackground(line_color) selection.format.setProperty(QtGui.QTextFormat.FullWidthSelection, True) selection.cursor = self.textCursor() selection.cursor.clearSelection() extra_selections.append(selection) self.setExtraSelections(extra_selections)