cola/widgets/highlighter.py

   1 from __future__ import division, absolute_import, unicode_literals
   2
   3 from qtpy import QtCore
   4 from qtpy import QtGui
   5 from qtpy import QtWidgets
   6
   7 have_pygments = True
   8 try:
   9     from pygments.styles import get_style_by_name
  10     from pygments import lex
  11     from pygments.util import ClassNotFound
  12     from pygments.lexers import get_lexer_for_filename
  13 except ImportError:
  14     have_pygments = False
  15
  16
  17 def highlight_document(edit, filename):
  18     if not have_pygments:
  19         return
  20     doc = edit.document()
  21     try:
  22         lexer = get_lexer_for_filename(filename, stripnl=False)
  23     except ClassNotFound:
  24         return
  25
  26     style = get_style_by_name('default')
  27
  28     font = doc.defaultFont()
  29     base_format = QtGui.QTextCharFormat()
  30     base_format.setFont(font)
  31     token_formats = {}
  32
  33     window = edit.window()
  34     if hasattr(window, 'processEvents'):
  35         processEvents = window.processEvents
  36     else:
  37         processEvents = QtCore.QCoreApplication.processEvents
  38
  39     def get_token_format(token):
  40         if token in token_formats:
  41             return token_formats[token]
  42
  43         if token.parent:
  44             parent_format = get_token_format(token.parent)
  45         else:
  46             parent_format = base_format
  47
  48         fmt = QtGui.QTextCharFormat(parent_format)
  49         font = fmt.font()
  50         if style.styles_token(token):
  51             tstyle = style.style_for_token(token)
  52             if tstyle['color']:
  53                 fmt.setForeground(QtGui.QColor('#' + tstyle['color']))
  54             if tstyle['bold']:
  55                 font.setWeight(QtGui.QFont.Bold)
  56             if tstyle['italic']:
  57                 font.setItalic(True)
  58             if tstyle['underline']:
  59                 fmt.setFontUnderline(True)
  60             if tstyle['bgcolor']:
  61                 fmt.setBackground(QtGui.QColor('#' + tstyle['bgcolor']))
  62         token_formats[token] = fmt
  63         return fmt
  64
  65     text = doc.toPlainText()
  66
  67     block_count = 0
  68     block = doc.firstBlock()
  69     assert isinstance(block, QtGui.QTextBlock)
  70     block_pos = 0
  71     block_len = block.length()
  72     block_formats = []
  73
  74     for token, ttext in lex(text, lexer):
  75         format_len = len(ttext)
  76         fmt = get_token_format(token)
  77         while format_len > 0:
  78             format_range = QtGui.QTextLayout.FormatRange()
  79             format_range.start = block_pos
  80             format_range.length = min(format_len, block_len)
  81             format_range.format = fmt
  82             block_formats.append(format_range)
  83             block_len -= format_range.length
  84             format_len -= format_range.length
  85             block_pos += format_range.length
  86             if block_len == 0:
  87                 block.layout().setAdditionalFormats(block_formats)
  88                 doc.markContentsDirty(block.position(), block.length())
  89                 block = block.next()  # pylint: disable=next-method-called
  90                 block_pos = 0
  91                 block_len = block.length()
  92                 block_formats = []
  93
  94                 block_count += 1
  95                 if block_count % 100 == 0:
  96                     processEvents()
  97
  98
  99 if __name__ == '__main__':
 100     app = QtWidgets.QApplication([])
 101
 102     python = QtWidgets.QPlainTextEdit()
 103     f = open(__file__, 'r')
 104     python.setPlainText(f.read())
 105     f.close()
 106
 107     python.setWindowTitle('python')
 108     python.show()
 109     highlight_document(python, __file__)
 110
 111     app.exec_()