How do you add folding to QsciLexerCustom subclass?
Consider this snippet:
import sys
import textwrap
import re
from PyQt5.Qt import * # noqa
from PyQt5.Qsci import QsciScintilla
from PyQt5.Qsci import QsciLexerCustom
from lark import Lark, inline_args, Transformer
class LexerJson(QsciLexerCustom):
def __init__(self, parent=None):
super().__init__(parent)
self.create_grammar()
self.create_styles()
def create_styles(self):
deeppink = QColor(249, 38, 114)
khaki = QColor(230, 219, 116)
mediumpurple = QColor(174, 129, 255)
mediumturquoise = QColor(81, 217, 205)
yellowgreen = QColor(166, 226, 46)
lightcyan = QColor(213, 248, 232)
darkslategrey = QColor(39, 40, 34)
styles = {
0: mediumturquoise,
1: mediumpurple,
2: yellowgreen,
3: deeppink,
4: khaki,
5: lightcyan
}
for style, color in styles.items():
self.setColor(color, style)
self.setPaper(darkslategrey, style)
self.setFont(self.parent().font(), style)
self.token_styles = {
"__COLON": 5,
"__COMMA": 5,
"__FALSE1": 0,
"__LBRACE": 5,
"__LSQB": 5,
"__NULL2": 0,
"__RBRACE": 5,
"__RSQB": 5,
"__TRUE0": 0,
"ESCAPED_STRING": 4,
"SIGNED_NUMBER": 1,
}
def create_grammar(self):
grammar = '''
?start: value
?value: object
| array
| string
| SIGNED_NUMBER -> number
| "true" -> true
| "false" -> false
| "null" -> null
array : "[" [value ("," value)*] "]"
object : "{" [pair ("," pair)*] "}"
pair : string ":" value
string : ESCAPED_STRING
%import common.ESCAPED_STRING
%import common.SIGNED_NUMBER
%import common.WS
%ignore WS
'''
class TreeToJson(Transformer):
@inline_args
def string(self, s):
return s[1:-1].replace('\\"', '"')
array = list
pair = tuple
object = dict
number = inline_args(float)
def null(self, _): return None
def true(self, _): return True
def false(self, _): return False
self.lark = Lark(grammar, parser='lalr', transformer=TreeToJson())
# All tokens: print([t.name for t in self.lark.parser.lexer.tokens])
def defaultPaper(self, style):
return QColor(39, 40, 34)
def language(self):
return "Json"
def description(self, style):
return {v: k for k, v in self.token_styles.items()}.get(style, "")
def styleText(self, start, end):
self.startStyling(start)
text = self.parent().text()[start:end]
last_pos = 0
try:
for token in self.lark.lex(text):
ws_len = token.pos_in_stream - last_pos
if ws_len:
self.setStyling(ws_len, 0) # whitespace
token_len = len(bytearray(token, "utf-8"))
self.setStyling(
token_len, self.token_styles.get(token.type, 0))
last_pos = token.pos_in_stream + token_len
except Exception as e:
print(e)
class EditorAll(QsciScintilla):
def __init__(self, parent=None):
super().__init__(parent)
# Set font defaults
font = QFont()
font.setFamily('Consolas')
font.setFixedPitch(True)
font.setPointSize(8)
font.setBold(True)
self.setFont(font)
# Set margin defaults
fontmetrics = QFontMetrics(font)
self.setMarginsFont(font)
self.setMarginWidth(0, fontmetrics.width("000") + 6)
self.setMarginLineNumbers(0, True)
self.setMarginsForegroundColor(QColor(128, 128, 128))
self.setMarginsBackgroundColor(QColor(39, 40, 34))
self.setMarginType(1, self.SymbolMargin)
self.setMarginWidth(1, 12)
# Set indentation defaults
self.setIndentationsUseTabs(False)
self.setIndentationWidth(4)
self.setBackspaceUnindents(True)
self.setIndentationGuides(True)
# Set folding defaults (http://www.scintilla.org/ScintillaDoc.html#Folding)
self.setFolding(QsciScintilla.CircledFoldStyle)
# Set caret defaults
self.setCaretForegroundColor(QColor(247, 247, 241))
self.setCaretWidth(2)
# Set selection color defaults
self.setSelectionBackgroundColor(QColor(61, 61, 52))
self.resetSelectionForegroundColor()
# Set multiselection defaults
self.SendScintilla(QsciScintilla.SCI_SETMULTIPLESELECTION, True)
self.SendScintilla(QsciScintilla.SCI_SETMULTIPASTE, 1)
self.SendScintilla(
QsciScintilla.SCI_SETADDITIONALSELECTIONTYPING, True)
lexer = LexerJson(self)
self.setLexer(lexer)
def main():
app = QApplication(sys.argv)
ex = EditorAll()
ex.setWindowTitle(__file__)
ex.setText(textwrap.dedent("""\
{
"_id": "5b05ffcbcf8e597939b3f5ca",
"about": "Excepteur consequat commodo esse voluptate aute aliquip ad sint deserunt commodo eiusmod irure. Sint aliquip sit magna duis eu est culpa aliqua excepteur ut tempor nulla. Aliqua ex pariatur id labore sit. Quis sit ex aliqua veniam exercitation laboris anim adipisicing. Lorem nisi reprehenderit ullamco labore qui sit ut aliqua tempor consequat pariatur proident.",
"address": "665 Malbone Street, Thornport, Louisiana, 243",
"age": 23,
"balance": "$3,216.91",
"company": "BULLJUICE",
"email": "elisekelley@bulljuice.com",
"eyeColor": "brown",
"gender": "female",
"guid": "d3a6d865-0f64-4042-8a78-4f53de9b0707",
"index": 0,
"isActive": false,
"isActive2": true,
"latitude": -18.660714,
"longitude": -85.378048,
"name": "Elise Kelley",
"phone": "+1 (808) 543-3966",
"picture": "http://placehold.it/32x32",
"registered": "2017-09-30T03:47:40 -02:00",
"tags": [
"et",
"nostrud",
"in",
"fugiat",
"incididunt",
"labore",
"nostrud"
]
}\
"""))
ex.resize(800, 600)
ex.show()
sys.exit(app.exec_())
if __name__ == "__main__":
main()
To run the above mcve you'll just need to run pip install lark-parser PyQt5 QScintilla
I'm trying to figure out how to modify LexerJson so the symbols [ ] { } will support folding. When using an existing class such as qscilexercpp.cpp the folding behaviour is given to you just for free, for instance, you'd just do something like:
# http://www.scintilla.org/ScintillaDoc.html#Folding
self.setFolding(QsciScintilla.BoxedTreeFoldStyle)
lexer = QsciLexerCPP()
lexer.setFoldAtElse(True)
lexer.setFoldComments(True)
lexer.setFoldCompact(False)
lexer.setFoldPreprocessor(True)
self.setLexer(lexer)
And folding would work just for free... but when using a custom lexer like I'm doing in the posted mcve I guess you got to implement that behaviour yourself, unfortunately I don't know how to do it.
So, that's basically the question, how do you implement folding on a QsciLexerCustom subclass?
Solution
I can't fix your lexer code, but I can give you a working example for the same
import sys
from PyQt5.Qt import *
from PyQt5.Qsci import QsciScintilla, QsciLexerCPP
from PyQt5.Qsci import QsciLexerCustom
if sys.hexversion < 0x020600F0:
print('python 2.6 or greater is required by this program')
sys.exit(1)
_sample = """
# Sample config file
this is a junk line
[FirstItem]
Width=100
Height=200
Colour=orange
Info=this is some
multiline
text
[SecondItem]
Width=200
Height=300
Colour=green
Info=
this is some
multiline
text
"""
class MainWindow(QMainWindow):
def __init__(self):
QMainWindow.__init__(self)
self.setWindowTitle('Custom Lexer For Config Files')
self.setGeometry(50, 200, 400, 400)
self.editor = QsciScintilla(self)
self.editor.setUtf8(True)
self.editor.setMarginWidth(2, 15)
self.editor.setFolding(True)
self.setCentralWidget(self.editor)
self.lexer = ConfigLexer(self.editor)
self.editor.setLexer(self.lexer)
self.editor.setText(_sample)
class ConfigLexer(QsciLexerCustom):
def __init__(self, parent):
QsciLexerCustom.__init__(self, parent)
self._styles = {
0: 'Default',
1: 'Comment',
2: 'Section',
3: 'Key',
4: 'Assignment',
5: 'Value',
}
for key,value in self._styles.items():
setattr(self, value, key)
self._foldcompact = True
def foldCompact(self):
return self._foldcompact
def setFoldCompact(self, enable):
self._foldcompact = bool(enable)
def language(self):
return 'Config Files'
def description(self, style):
return self._styles.get(style, '')
def defaultColor(self, style):
if style == self.Default:
return QColor('#000000')
elif style == self.Comment:
return QColor('#A0A0A0')
elif style == self.Section:
return QColor('#CC6600')
elif style == self.Key:
return QColor('#0000CC')
elif style == self.Assignment:
return QColor('#CC0000')
elif style == self.Value:
return QColor('#00CC00')
return QsciLexerCustom.defaultColor(self, style)
def defaultPaper(self, style):
if style == self.Section:
return QColor('#FFEECC')
return QsciLexerCustom.defaultPaper(self, style)
def defaultEolFill(self, style):
if style == self.Section:
return True
return QsciLexerCustom.defaultEolFill(self, style)
def defaultFont(self, style):
if style == self.Comment:
if sys.platform in ('win32', 'cygwin'):
return QFont('Comic Sans MS', 9)
return QFont('Bitstream Vera Serif', 9)
return QsciLexerCustom.defaultFont(self, style)
def styleText(self, start, end):
editor = self.editor()
if editor is None:
return
SCI = editor.SendScintilla
GETFOLDLEVEL = QsciScintilla.SCI_GETFOLDLEVEL
SETFOLDLEVEL = QsciScintilla.SCI_SETFOLDLEVEL
HEADERFLAG = QsciScintilla.SC_FOLDLEVELHEADERFLAG
LEVELBASE = QsciScintilla.SC_FOLDLEVELBASE
NUMBERMASK = QsciScintilla.SC_FOLDLEVELNUMBERMASK
WHITEFLAG = QsciScintilla.SC_FOLDLEVELWHITEFLAG
set_style = self.setStyling
source = ''
if end > editor.length():
end = editor.length()
if end > start:
source = bytearray(end - start)
SCI(QsciScintilla.SCI_GETTEXTRANGE, start, end, source)
if not source:
return
compact = self.foldCompact()
index = SCI(QsciScintilla.SCI_LINEFROMPOSITION, start)
if index > 0:
pos = SCI(QsciScintilla.SCI_GETLINEENDPOSITION, index - 1)
state = SCI(QsciScintilla.SCI_GETSTYLEAT, pos)
else:
state = self.Default
self.startStyling(start, 0x1f)
for line in source.splitlines(True):
length = len(line)
if length == 1:
whitespace = compact
state = self.Default
else:
whitespace = False
firstchar = chr(line[0])
if firstchar in '#;':
state = self.Comment
elif firstchar == '[':
state = self.Section
elif firstchar in ' \t':
if state == self.Value or state == self.Assignment:
state = self.Value
else:
whitespace = compact and line.isspace()
state = self.Default
else:
pos = line.find(b'=')
if pos < 0:
pos = line.find(b':')
else:
tmp = line.find(b':', 0, pos)
if tmp >= 0:
pos = tmp
if pos > 0:
set_style(pos, self.Key)
set_style(1, self.Assignment)
length = length - pos - 1
state = self.Value
else:
state = self.Default
set_style(length, state)
if state == self.Section:
level = LEVELBASE | HEADERFLAG
elif index > 0:
lastlevel = SCI(GETFOLDLEVEL, index - 1)
if lastlevel & HEADERFLAG:
level = LEVELBASE + 1
else:
level = lastlevel & NUMBERMASK
else:
level = LEVELBASE
if whitespace:
level |= WHITEFLAG
if level != SCI(GETFOLDLEVEL, index):
SCI(SETFOLDLEVEL, index, level)
index += 1
if index > 0:
lastlevel = SCI(GETFOLDLEVEL, index - 1)
if lastlevel & HEADERFLAG:
level = LEVELBASE + 1
else:
level = lastlevel & NUMBERMASK
else:
level = LEVELBASE
lastlevel = SCI(GETFOLDLEVEL, index)
SCI(SETFOLDLEVEL, index, level | lastlevel & ~NUMBERMASK)
if __name__ == "__main__":
app = QApplication(sys.argv)
win = MainWindow()
win.show()
sys.exit(app.exec_())
The key stuff happens here
if state == self.Section:
level = LEVELBASE | HEADERFLAG
elif index > 0:
lastlevel = SCI(GETFOLDLEVEL, index - 1)
if lastlevel & HEADERFLAG:
level = LEVELBASE + 1
else:
level = lastlevel & NUMBERMASK
else:
level = LEVELBASE
if whitespace:
level |= WHITEFLAG
if level != SCI(GETFOLDLEVEL, index):
SCI(SETFOLDLEVEL, index, level)
index += 1
if index > 0:
lastlevel = SCI(GETFOLDLEVEL, index - 1)
if lastlevel & HEADERFLAG:
level = LEVELBASE + 1
else:
level = lastlevel & NUMBERMASK
else:
level = LEVELBASE
lastlevel = SCI(GETFOLDLEVEL, index)
SCI(SETFOLDLEVEL, index, level | lastlevel & ~NUMBERMASK)
PS: Credits to https://github.com/pingf/toys/blob/f808e7c4ed1a76db4800c8e1ee6d163242df52cc/src/201403/customLexer2.py
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