177 lines
8.2 KiB
Python
177 lines
8.2 KiB
Python
|
"""CodeContext - Extension to display the block context above the edit window
|
||
|
|
|
||
|
|
Once code has scrolled off the top of a window, it can be difficult to
|
||
|
|
determine which block you are in. This extension implements a pane at the top
|
||
|
|
of each IDLE edit window which provides block structure hints. These hints are
|
||
|
|
the lines which contain the block opening keywords, e.g. 'if', for the
|
||
|
|
enclosing block. The number of hint lines is determined by the numlines
|
||
|
|
variable in the CodeContext section of config-extensions.def. Lines which do
|
||
|
|
not open blocks are not shown in the context hints pane.
|
||
|
|
|
||
|
|
"""
|
||
|
|
import tkinter
|
||
|
|
from tkinter.constants import TOP, LEFT, X, W, SUNKEN
|
||
|
|
import re
|
||
|
|
from sys import maxsize as INFINITY
|
||
|
|
from idlelib.configHandler import idleConf
|
||
|
|
|
||
|
|
BLOCKOPENERS = {"class", "def", "elif", "else", "except", "finally", "for",
|
||
|
|
"if", "try", "while", "with"}
|
||
|
|
UPDATEINTERVAL = 100 # millisec
|
||
|
|
FONTUPDATEINTERVAL = 1000 # millisec
|
||
|
|
|
||
|
|
getspacesfirstword =\
|
||
|
|
lambda s, c=re.compile(r"^(\s*)(\w*)"): c.match(s).groups()
|
||
|
|
|
||
|
|
class CodeContext:
|
||
|
|
menudefs = [('options', [('!Code Conte_xt', '<<toggle-code-context>>')])]
|
||
|
|
context_depth = idleConf.GetOption("extensions", "CodeContext",
|
||
|
|
"numlines", type="int", default=3)
|
||
|
|
bgcolor = idleConf.GetOption("extensions", "CodeContext",
|
||
|
|
"bgcolor", type="str", default="LightGray")
|
||
|
|
fgcolor = idleConf.GetOption("extensions", "CodeContext",
|
||
|
|
"fgcolor", type="str", default="Black")
|
||
|
|
def __init__(self, editwin):
|
||
|
|
self.editwin = editwin
|
||
|
|
self.text = editwin.text
|
||
|
|
self.textfont = self.text["font"]
|
||
|
|
self.label = None
|
||
|
|
# self.info is a list of (line number, indent level, line text, block
|
||
|
|
# keyword) tuples providing the block structure associated with
|
||
|
|
# self.topvisible (the linenumber of the line displayed at the top of
|
||
|
|
# the edit window). self.info[0] is initialized as a 'dummy' line which
|
||
|
|
# starts the toplevel 'block' of the module.
|
||
|
|
self.info = [(0, -1, "", False)]
|
||
|
|
self.topvisible = 1
|
||
|
|
visible = idleConf.GetOption("extensions", "CodeContext",
|
||
|
|
"visible", type="bool", default=False)
|
||
|
|
if visible:
|
||
|
|
self.toggle_code_context_event()
|
||
|
|
self.editwin.setvar('<<toggle-code-context>>', True)
|
||
|
|
# Start two update cycles, one for context lines, one for font changes.
|
||
|
|
self.text.after(UPDATEINTERVAL, self.timer_event)
|
||
|
|
self.text.after(FONTUPDATEINTERVAL, self.font_timer_event)
|
||
|
|
|
||
|
|
def toggle_code_context_event(self, event=None):
|
||
|
|
if not self.label:
|
||
|
|
# Calculate the border width and horizontal padding required to
|
||
|
|
# align the context with the text in the main Text widget.
|
||
|
|
#
|
||
|
|
# All values are passed through getint(), since some
|
||
|
|
# values may be pixel objects, which can't simply be added to ints.
|
||
|
|
widgets = self.editwin.text, self.editwin.text_frame
|
||
|
|
# Calculate the required vertical padding
|
||
|
|
padx = 0
|
||
|
|
for widget in widgets:
|
||
|
|
padx += widget.tk.getint(widget.pack_info()['padx'])
|
||
|
|
padx += widget.tk.getint(widget.cget('padx'))
|
||
|
|
# Calculate the required border width
|
||
|
|
border = 0
|
||
|
|
for widget in widgets:
|
||
|
|
border += widget.tk.getint(widget.cget('border'))
|
||
|
|
self.label = tkinter.Label(self.editwin.top,
|
||
|
|
text="\n" * (self.context_depth - 1),
|
||
|
|
anchor=W, justify=LEFT,
|
||
|
|
font=self.textfont,
|
||
|
|
bg=self.bgcolor, fg=self.fgcolor,
|
||
|
|
width=1, #don't request more than we get
|
||
|
|
padx=padx, border=border,
|
||
|
|
relief=SUNKEN)
|
||
|
|
# Pack the label widget before and above the text_frame widget,
|
||
|
|
# thus ensuring that it will appear directly above text_frame
|
||
|
|
self.label.pack(side=TOP, fill=X, expand=False,
|
||
|
|
before=self.editwin.text_frame)
|
||
|
|
else:
|
||
|
|
self.label.destroy()
|
||
|
|
self.label = None
|
||
|
|
idleConf.SetOption("extensions", "CodeContext", "visible",
|
||
|
|
str(self.label is not None))
|
||
|
|
idleConf.SaveUserCfgFiles()
|
||
|
|
|
||
|
|
def get_line_info(self, linenum):
|
||
|
|
"""Get the line indent value, text, and any block start keyword
|
||
|
|
|
||
|
|
If the line does not start a block, the keyword value is False.
|
||
|
|
The indentation of empty lines (or comment lines) is INFINITY.
|
||
|
|
|
||
|
|
"""
|
||
|
|
text = self.text.get("%d.0" % linenum, "%d.end" % linenum)
|
||
|
|
spaces, firstword = getspacesfirstword(text)
|
||
|
|
opener = firstword in BLOCKOPENERS and firstword
|
||
|
|
if len(text) == len(spaces) or text[len(spaces)] == '#':
|
||
|
|
indent = INFINITY
|
||
|
|
else:
|
||
|
|
indent = len(spaces)
|
||
|
|
return indent, text, opener
|
||
|
|
|
||
|
|
def get_context(self, new_topvisible, stopline=1, stopindent=0):
|
||
|
|
"""Get context lines, starting at new_topvisible and working backwards.
|
||
|
|
|
||
|
|
Stop when stopline or stopindent is reached. Return a tuple of context
|
||
|
|
data and the indent level at the top of the region inspected.
|
||
|
|
|
||
|
|
"""
|
||
|
|
assert stopline > 0
|
||
|
|
lines = []
|
||
|
|
# The indentation level we are currently in:
|
||
|
|
lastindent = INFINITY
|
||
|
|
# For a line to be interesting, it must begin with a block opening
|
||
|
|
# keyword, and have less indentation than lastindent.
|
||
|
|
for linenum in range(new_topvisible, stopline-1, -1):
|
||
|
|
indent, text, opener = self.get_line_info(linenum)
|
||
|
|
if indent < lastindent:
|
||
|
|
lastindent = indent
|
||
|
|
if opener in ("else", "elif"):
|
||
|
|
# We also show the if statement
|
||
|
|
lastindent += 1
|
||
|
|
if opener and linenum < new_topvisible and indent >= stopindent:
|
||
|
|
lines.append((linenum, indent, text, opener))
|
||
|
|
if lastindent <= stopindent:
|
||
|
|
break
|
||
|
|
lines.reverse()
|
||
|
|
return lines, lastindent
|
||
|
|
|
||
|
|
def update_code_context(self):
|
||
|
|
"""Update context information and lines visible in the context pane.
|
||
|
|
|
||
|
|
"""
|
||
|
|
new_topvisible = int(self.text.index("@0,0").split('.')[0])
|
||
|
|
if self.topvisible == new_topvisible: # haven't scrolled
|
||
|
|
return
|
||
|
|
if self.topvisible < new_topvisible: # scroll down
|
||
|
|
lines, lastindent = self.get_context(new_topvisible,
|
||
|
|
self.topvisible)
|
||
|
|
# retain only context info applicable to the region
|
||
|
|
# between topvisible and new_topvisible:
|
||
|
|
while self.info[-1][1] >= lastindent:
|
||
|
|
del self.info[-1]
|
||
|
|
elif self.topvisible > new_topvisible: # scroll up
|
||
|
|
stopindent = self.info[-1][1] + 1
|
||
|
|
# retain only context info associated
|
||
|
|
# with lines above new_topvisible:
|
||
|
|
while self.info[-1][0] >= new_topvisible:
|
||
|
|
stopindent = self.info[-1][1]
|
||
|
|
del self.info[-1]
|
||
|
|
lines, lastindent = self.get_context(new_topvisible,
|
||
|
|
self.info[-1][0]+1,
|
||
|
|
stopindent)
|
||
|
|
self.info.extend(lines)
|
||
|
|
self.topvisible = new_topvisible
|
||
|
|
# empty lines in context pane:
|
||
|
|
context_strings = [""] * max(0, self.context_depth - len(self.info))
|
||
|
|
# followed by the context hint lines:
|
||
|
|
context_strings += [x[2] for x in self.info[-self.context_depth:]]
|
||
|
|
self.label["text"] = '\n'.join(context_strings)
|
||
|
|
|
||
|
|
def timer_event(self):
|
||
|
|
if self.label:
|
||
|
|
self.update_code_context()
|
||
|
|
self.text.after(UPDATEINTERVAL, self.timer_event)
|
||
|
|
|
||
|
|
def font_timer_event(self):
|
||
|
|
newtextfont = self.text["font"]
|
||
|
|
if self.label and newtextfont != self.textfont:
|
||
|
|
self.textfont = newtextfont
|
||
|
|
self.label["font"] = self.textfont
|
||
|
|
self.text.after(FONTUPDATEINTERVAL, self.font_timer_event)
|