python code Editor in pyqt5 , view source line, syntax highlighting

개인적인 툴을 제작 하던 중에, 파이썬 소스코드를 읽어와서 QPlainTextEdit 로 보여주어야 할 일이 생겨서 코드를 만들었습니다. (만들었다기 보단 인터넷에 있는걸 합쳐놨어요. 두개가 분리되있어서 조금 귀찮긴 하더라고요)

출처(view line, selection color) : 

 https://stackoverflow.com/questions/40386194/create-text-area-textedit-with-line-number-in-pyqt

출처(syntax highlighting) : 

   https://wiki.python.org/moin/PyQt/Python%20syntax%20highlighting

codeeditor.py 를 qtdesigner 에서 promote 시켜서 사용 하시면 됩니다.<그림2 참조, 모르시면 댓글남기시면... 언젠간 답변 드릴 수도?>   http://4uwingnet.tistory.com/8 에 포스팅이 완료되었습니다. 참조하세요.

<codeeditor.py 실행 화면>

< qtdesigner 에서 QPlainTextEdit을 CodeEditor로 promote 시킨 화면>

< codeeditor.py >

"""
original author : 
__author__ = https://stackoverflow.com/users/839338/dan-dev
"""
 
__author__ = "Seounghun, Chung <4uwingnet@naver.com>"
__license__ = "License:BSD 3Clause"
 
from PyQt5.QtGui import *
from PyQt5.QtCore import *
from PyQt5.QtWidgets import *
import syntax
 
class LineNumberArea(QWidget):
 
 
    def __init__(self, editor):
        super().__init__(editor)
        self.myeditor = editor
 
 
    def sizeHint(self):
        return Qsize(self.editor.lineNumberAreaWidth(), 0)
 
 
    def paintEvent(self, event):
        self.myeditor.lineNumberAreaPaintEvent(event)
 
 
class CodeEditor(QPlainTextEdit):
    def __init__(self, parent = None):
        super(CodeEditor,self).__init__(parent)
        self.highlight = syntax.PythonHighlighter(self.document())
        
        self.lineNumberArea = LineNumberArea(self)
 
        self.blockCountChanged.connect(self.updateLineNumberAreaWidth)
        self.updateRequest.connect(self.updateLineNumberArea)
        self.cursorPositionChanged.connect(self.highlightCurrentLine)
        
        self.updateLineNumberAreaWidth(0)
 
 
    def lineNumberAreaWidth(self):
        digits = 1
        count = max(1, self.blockCount())
        while count >= 10:
            count /= 10
            digits += 1
        space = 3 + self.fontMetrics().width('9') * digits
        return space
 
 
    def updateLineNumberAreaWidth(self, _):
        self.setViewportMargins(self.lineNumberAreaWidth(), 0, 0, 0)
 
 
    def updateLineNumberArea(self, rect, dy):
 
        if dy:
            self.lineNumberArea.scroll(0, dy)
        else:
            self.lineNumberArea.update(0, rect.y(), self.lineNumberArea.width(),
                       rect.height())
 
        if rect.contains(self.viewport().rect()):
            self.updateLineNumberAreaWidth(0)
 
 
    def resizeEvent(self, event):
        super().resizeEvent(event)
 
        cr = self.contentsRect();
        self.lineNumberArea.setGeometry(QRect(cr.left(), cr.top(),
                    self.lineNumberAreaWidth(), cr.height()))
 
 
    def lineNumberAreaPaintEvent(self, event):
        mypainter = QPainter(self.lineNumberArea)
 
        mypainter.fillRect(event.rect(), Qt.lightGray)
 
        block = self.firstVisibleBlock()
        blockNumber = 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 <= event.rect().bottom()):
            if block.isVisible() and (bottom >= event.rect().top()):
                number = str(blockNumber + 1)
                mypainter.setPen(Qt.black)
                mypainter.drawText(0, top, self.lineNumberArea.width(), height,
                 Qt.AlignRight, number)
 
            block = block.next()
            top = bottom
            bottom = top + self.blockBoundingRect(block).height()
            blockNumber += 1
 
 
    def highlightCurrentLine(self):
        extraSelections = []
 
        if not self.isReadOnly():
            selection = QTextEdit.ExtraSelection()
 
            lineColor = QColor(Qt.yellow).lighter(185)
 
            selection.format.setBackground(lineColor)
            selection.format.setProperty(QTextFormat.FullWidthSelection, True)
            selection.cursor = self.textCursor()
            selection.cursor.clearSelection()
            extraSelections.append(selection)
        self.setExtraSelections(extraSelections)
 
if __name__ == '__main__':
    import sys
    from PyQt5.QtWidgets import QApplication
 
    app = QApplication(sys.argv)
    codeEditor = CodeEditor()
    with open("syntax.py","r") as f:
        codeEditor.setPlainText(f.read())
    codeEditor.show()    
    sys.exit(app.exec_())        

< syntax.py >

"""
original author : 
__author__ = https://wiki.python.org/moin/PyQt/Python%20syntax%20highlighting
"""
__author__ = "Seounghun, Chung <4uwingnet@naver.com>"
__license__ = "License:BSD 3Clause"
 
 
import sys
 
from PyQt5.QtCore import QRegExp
from PyQt5.QtGui import QColor, QTextCharFormat, QFont, QSyntaxHighlighter
from PyQt5.QtWidgets import *
 
def format(color, style=''):
    """Return a QTextCharFormat with the given attributes.
    """
    _color = QColor()
    _color.setNamedColor(color)
 
    _format = QTextCharFormat()
    _format.setForeground(_color)
    if 'bold' in style:
        _format.setFontWeight(QFont.Bold)
    if 'italic' in style:
        _format.setFontItalic(True)
 
    return _format
 
 
# Syntax styles that can be shared by all languages
STYLES = {
    'keyword': format('blue'),
    'operator': format('red'),
    'brace': format('Gray'),
    'defclass': format('black', 'bold'),
    'string': format('magenta'),
    'string2': format('darkMagenta'),
    'comment': format('darkGreen', 'italic'),
    'self': format('black', 'italic'),
    'numbers': format('brown'),
}
 
 
class PythonHighlighter (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',
    ]
 
    # Python operators
    operators = [
        '=',
        # Comparison
        '==', '!=', '<', '<=', '>', '>=',
        # Arithmetic
        '\+', '-', '\*', '/', '//', '\%', '\*\*',
        # In-place
        '\+=', '-=', '\*=', '/=', '\%=',
        # Bitwise
        '\^', '\|', '\&', '\~', '>>', '<<',
    ]
 
    # Python braces
    braces = [
        '\{', '\}', '\(', '\)', '\[', '\]',
    ]
    def __init__(self, document):
        QSyntaxHighlighter.__init__(self, 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 = (QRegExp("'''"), 1, STYLES['string2'])
        self.tri_double = (QRegExp('"""'), 2, STYLES['string2'])
 
        rules = []
 
        # Keyword, operator, and brace rules
        rules += [(r'\b%s\b' % w, 0, STYLES['keyword'])
            for w in PythonHighlighter.keywords]
        rules += [(r'%s' % o, 0, STYLES['operator'])
            for o in PythonHighlighter.operators]
        rules += [(r'%s' % b, 0, STYLES['brace'])
            for b in PythonHighlighter.braces]
 
        # All other rules
        rules += [
            # 'self'
            (r'\bself\b', 0, STYLES['self']),
 
            # Double-quoted string, possibly containing escape sequences
            (r'"[^"\\]*(\\.[^"\\]*)*"', 0, STYLES['string']),
            # Single-quoted string, possibly containing escape sequences
            (r"'[^'\\]*(\\.[^'\\]*)*'", 0, STYLES['string']),
 
            # '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']),
 
            # From '#' until a newline
            (r'#[^\n]*', 0, STYLES['comment']),
 
            # Numeric literals
            (r'\b[+-]?[0-9]+[lL]?\b', 0, STYLES['numbers']),
            (r'\b[+-]?0[xX][0-9A-Fa-f]+[lL]?\b', 0, STYLES['numbers']),
            (r'\b[+-]?[0-9]+(?:\.[0-9]+)?(?:[eE][+-]?[0-9]+)?\b', 0, STYLES['numbers']),
        ]
 
        # Build a QRegExp for each pattern
        self.rules = [(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, format 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, format)
                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):
        """Do 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)
                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