summaryrefslogtreecommitdiffstats
path: root/Lib/idlelib/SearchEngine.py
diff options
context:
space:
mode:
Diffstat (limited to 'Lib/idlelib/SearchEngine.py')
-rw-r--r--Lib/idlelib/SearchEngine.py110
1 files changed, 62 insertions, 48 deletions
diff --git a/Lib/idlelib/SearchEngine.py b/Lib/idlelib/SearchEngine.py
index 13a6a6b..9d3c4cb 100644
--- a/Lib/idlelib/SearchEngine.py
+++ b/Lib/idlelib/SearchEngine.py
@@ -1,26 +1,34 @@
+'''Define SearchEngine for search dialogs.'''
import re
-from tkinter import *
+from tkinter import StringVar, BooleanVar, TclError
import tkinter.messagebox as tkMessageBox
def get(root):
+ '''Return the singleton SearchEngine instance for the process.
+
+ The single SearchEngine saves settings between dialog instances.
+ If there is not a SearchEngine already, make one.
+ '''
if not hasattr(root, "_searchengine"):
root._searchengine = SearchEngine(root)
- # XXX This will never garbage-collect -- who cares
+ # This creates a cycle that persists until root is deleted.
return root._searchengine
class SearchEngine:
+ """Handles searching a text widget for Find, Replace, and Grep."""
def __init__(self, root):
- self.root = root
- # State shared by search, replace, and grep;
- # the search dialogs bind these to UI elements.
- self.patvar = StringVar(root) # search pattern
- self.revar = BooleanVar(root) # regular expression?
- self.casevar = BooleanVar(root) # match case?
- self.wordvar = BooleanVar(root) # match whole word?
- self.wrapvar = BooleanVar(root) # wrap around buffer?
- self.wrapvar.set(1) # (on by default)
- self.backvar = BooleanVar(root) # search backwards?
+ '''Initialize Variables that save search state.
+
+ The dialogs bind these to the UI elements present in the dialogs.
+ '''
+ self.root = root # need for report_error()
+ self.patvar = StringVar(root, '') # search pattern
+ self.revar = BooleanVar(root, False) # regular expression?
+ self.casevar = BooleanVar(root, False) # match case?
+ self.wordvar = BooleanVar(root, False) # match whole word?
+ self.wrapvar = BooleanVar(root, True) # wrap around buffer?
+ self.backvar = BooleanVar(root, False) # search backwards?
# Access methods
@@ -47,15 +55,23 @@ class SearchEngine:
# Higher level access methods
+ def setcookedpat(self, pat):
+ "Set pattern after escaping if re."
+ # called only in SearchDialog.py: 66
+ if self.isre():
+ pat = re.escape(pat)
+ self.setpat(pat)
+
def getcookedpat(self):
pat = self.getpat()
- if not self.isre():
+ if not self.isre(): # if True, see setcookedpat
pat = re.escape(pat)
if self.isword():
pat = r"\b%s\b" % pat
return pat
def getprog(self):
+ "Return compiled cooked search pattern."
pat = self.getpat()
if not pat:
self.report_error(pat, "Empty regular expression")
@@ -67,50 +83,41 @@ class SearchEngine:
try:
prog = re.compile(pat, flags)
except re.error as what:
- try:
- msg, col = what
- except:
- msg = str(what)
- col = -1
+ args = what.args
+ msg = args[0]
+ col = arg[1] if len(args) >= 2 else -1
self.report_error(pat, msg, col)
return None
return prog
def report_error(self, pat, msg, col=-1):
- # Derived class could overrid this with something fancier
+ # Derived class could override this with something fancier
msg = "Error: " + str(msg)
if pat:
- msg = msg + "\np\Pattern: " + str(pat)
+ msg = msg + "\nPattern: " + str(pat)
if col >= 0:
msg = msg + "\nOffset: " + str(col)
tkMessageBox.showerror("Regular expression error",
msg, master=self.root)
- def setcookedpat(self, pat):
- if self.isre():
- pat = re.escape(pat)
- self.setpat(pat)
-
def search_text(self, text, prog=None, ok=0):
- """Search a text widget for the pattern.
+ '''Return (lineno, matchobj) or None for forward/backward search.
- If prog is given, it should be the precompiled pattern.
- Return a tuple (lineno, matchobj); None if not found.
+ This function calls the right function with the right arguments.
+ It directly return the result of that call.
- This obeys the wrap and direction (back) settings.
+ Text is a text widget. Prog is a precompiled pattern.
+ The ok parameteris a bit complicated as it has two effects.
- The search starts at the selection (if there is one) or
- at the insert mark (otherwise). If the search is forward,
- it starts at the right of the selection; for a backward
- search, it starts at the left end. An empty match exactly
- at either end of the selection (or at the insert mark if
- there is no selection) is ignored unless the ok flag is true
- -- this is done to guarantee progress.
+ If there is a selection, the search begin at either end,
+ depending on the direction setting and ok, with ok meaning that
+ the search starts with the selection. Otherwise, search begins
+ at the insert mark.
- If the search is allowed to wrap around, it will return the
- original selection if (and only if) it is the only match.
+ To aid progress, the search functions do not return an empty
+ match at the starting position unless ok is True.
+ '''
- """
if not prog:
prog = self.getprog()
if not prog:
@@ -179,15 +186,19 @@ class SearchEngine:
col = len(chars) - 1
return None
-# Helper to search backwards in a string.
-# (Optimized for the case where the pattern isn't found.)
-
def search_reverse(prog, chars, col):
+ '''Search backwards and return an re match object or None.
+
+ This is done by searching forwards until there is no match.
+ Prog: compiled re object with a search method returning a match.
+ Chars: line of text, without \n.
+ Col: stop index for the search; the limit for match.end().
+ '''
m = prog.search(chars)
if not m:
return None
found = None
- i, j = m.span()
+ i, j = m.span() # m.start(), m.end() == match slice indexes
while i < col and j <= col:
found = m
if i == j:
@@ -198,10 +209,9 @@ def search_reverse(prog, chars, col):
i, j = m.span()
return found
-# Helper to get selection end points, defaulting to insert mark.
-# Return a tuple of indices ("line.col" strings).
-
def get_selection(text):
+ '''Return tuple of 'line.col' indexes from selection or insert mark.
+ '''
try:
first = text.index("sel.first")
last = text.index("sel.last")
@@ -213,8 +223,12 @@ def get_selection(text):
last = first
return first, last
-# Helper to parse a text index into a (line, col) tuple.
-
def get_line_col(index):
+ '''Return (line, col) tuple of ints from 'line.col' string.'''
line, col = map(int, index.split(".")) # Fails on invalid index
return line, col
+
+if __name__ == "__main__":
+ from test import support; support.use_resources = ['gui']
+ import unittest
+ unittest.main('idlelib.idle_test.test_searchengine', verbosity=2, exit=False)