1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
|
'''Define SearchEngine for search dialogs.'''
import re
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)
# 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):
'''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
def getpat(self):
return self.patvar.get()
def setpat(self, pat):
self.patvar.set(pat)
def isre(self):
return self.revar.get()
def iscase(self):
return self.casevar.get()
def isword(self):
return self.wordvar.get()
def iswrap(self):
return self.wrapvar.get()
def isback(self):
return self.backvar.get()
# 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 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")
return None
pat = self.getcookedpat()
flags = 0
if not self.iscase():
flags = flags | re.IGNORECASE
try:
prog = re.compile(pat, flags)
except re.error as what:
args = what.args
msg = args[0]
col = args[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 override this with something fancier
msg = "Error: " + str(msg)
if pat:
msg = msg + "\nPattern: " + str(pat)
if col >= 0:
msg = msg + "\nOffset: " + str(col)
tkMessageBox.showerror("Regular expression error",
msg, master=self.root)
def search_text(self, text, prog=None, ok=0):
'''Return (lineno, matchobj) or None for forward/backward search.
This function calls the right function with the right arguments.
It directly return the result of that call.
Text is a text widget. Prog is a precompiled pattern.
The ok parameter is a bit complicated as it has two effects.
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.
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:
return None # Compilation failed -- stop
wrap = self.wrapvar.get()
first, last = get_selection(text)
if self.isback():
if ok:
start = last
else:
start = first
line, col = get_line_col(start)
res = self.search_backward(text, prog, line, col, wrap, ok)
else:
if ok:
start = first
else:
start = last
line, col = get_line_col(start)
res = self.search_forward(text, prog, line, col, wrap, ok)
return res
def search_forward(self, text, prog, line, col, wrap, ok=0):
wrapped = 0
startline = line
chars = text.get("%d.0" % line, "%d.0" % (line+1))
while chars:
m = prog.search(chars[:-1], col)
if m:
if ok or m.end() > col:
return line, m
line = line + 1
if wrapped and line > startline:
break
col = 0
ok = 1
chars = text.get("%d.0" % line, "%d.0" % (line+1))
if not chars and wrap:
wrapped = 1
wrap = 0
line = 1
chars = text.get("1.0", "2.0")
return None
def search_backward(self, text, prog, line, col, wrap, ok=0):
wrapped = 0
startline = line
chars = text.get("%d.0" % line, "%d.0" % (line+1))
while 1:
m = search_reverse(prog, chars[:-1], col)
if m:
if ok or m.start() < col:
return line, m
line = line - 1
if wrapped and line < startline:
break
ok = 1
if line <= 0:
if not wrap:
break
wrapped = 1
wrap = 0
pos = text.index("end-1c")
line, col = map(int, pos.split("."))
chars = text.get("%d.0" % line, "%d.0" % (line+1))
col = len(chars) - 1
return None
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() # m.start(), m.end() == match slice indexes
while i < col and j <= col:
found = m
if i == j:
j = j+1
m = prog.search(chars, j)
if not m:
break
i, j = m.span()
return found
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")
except TclError:
first = last = None
if not first:
first = text.index("insert")
if not last:
last = first
return first, last
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__":
import unittest
unittest.main('idlelib.idle_test.test_searchengine', verbosity=2, exit=False)
|
