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
|
"""text_file
provides the TextFile class, which gives an interface to text files
that (optionally) takes care of stripping comments, ignoring blank
lines, and joining lines with backslashes."""
# created 1999/01/12, Greg Ward
__revision__ = "$Id$"
from types import *
import sys, os, string, re
class TextFile:
filename = None
file = None
current_line = None
default_options = { 'strip_comments': 1,
'comment_re': re.compile (r'\s*#.*'),
'skip_blanks': 1,
'join_lines': 0,
'lstrip_ws': 0,
'rstrip_ws': 1,
}
def __init__ (self, filename=None, **options):
# set values for all options -- either from client option hash
# or fallback to default_options
for opt in self.default_options.keys():
if options.has_key (opt):
if opt == 'comment_re' and type (options[opt]) is StringType:
self.comment_re = re.compile (options[opt])
else:
setattr (self, opt, options[opt])
else:
setattr (self, opt, self.default_options[opt])
# sanity check client option hash
for opt in options.keys():
if not self.default_options.has_key (opt):
raise KeyError, "invalid TextFile option '%s'" % opt
self.filename = filename
if self.filename:
self.open ()
def open (self, filename=None):
if not self.filename:
if not filename:
raise RuntimeError, "must provide a filename somehow"
self.filename = filename
self.file = open (self.filename, 'r')
self.current_line = 0
def close (self):
self.file.close ()
self.file = None
self.filename = None
self.current_line = None
def warn (self, msg):
sys.stderr.write (self.filename + ", ")
if type (self.current_line) is ListType:
sys.stderr.write ("lines %d-%d: " % tuple (self.current_line))
else:
sys.stderr.write ("line %d: " % self.current_line)
sys.stderr.write (msg + "\n")
def readline (self):
buildup_line = ''
while 1:
# read the line, optionally strip comments
line = self.file.readline()
if self.strip_comments and line:
line = self.comment_re.sub ('', line)
# did previous line end with a backslash? then accumulate
if self.join_lines and buildup_line:
# oops: end of file
if not line:
self.warn ("continuation line immediately precedes "
"end-of-file")
return buildup_line
line = buildup_line + line
# careful: pay attention to line number when incrementing it
if type (self.current_line) is ListType:
self.current_line[1] = self.current_line[1] + 1
else:
self.current_line = [self.current_line, self.current_line+1]
# just an ordinary line, read it as usual
else:
if not line:
return None
# still have to be careful about incrementing the line number!
if type (self.current_line) is ListType:
self.current_line = self.current_line[1] + 1
else:
self.current_line = self.current_line + 1
# strip whitespace however the client wants (leading and
# trailing, or one or the other, or neither)
if self.lstrip_ws and self.rstrip_ws:
line = string.strip (line)
else:
if self.lstrip_ws:
line = string.lstrip (line)
if self.rstrip_ws:
line = string.rstrip (line)
# blank line (whether we rstrip'ed or not)? skip to next line
# if appropriate
if line == '' or line == '\n' and self.skip_blanks:
continue
if self.join_lines:
if line[-1] == '\\':
buildup_line = line[:-1]
continue
if line[-2:] == '\\\n':
buildup_line = line[0:-2] + '\n'
continue
# well, I guess there's some actual content there: return it
return line
# end readline
def readlines (self):
lines = []
while 1:
line = self.readline()
if line is None:
return lines
lines.append (line)
if __name__ == "__main__":
test_data = """# test file
line 3 \\
continues on next line
"""
# result 1: no fancy options
result1 = map (lambda x: x + "\n", string.split (test_data, "\n")[0:-1])
# result 2: just strip comments
result2 = ["\n", "\n", "line 3 \\\n", "continues on next line\n"]
# result 3: just strip blank lines
result3 = ["# test file\n", "line 3 \\\n", "continues on next line\n"]
# result 4: default, strip comments, blank lines, and trailing whitespace
result4 = ["line 3 \\", "continues on next line"]
# result 5: full processing, strip comments and blanks, plus join lines
result5 = ["line 3 continues on next line"]
def test_input (count, description, file, expected_result):
result = file.readlines ()
# result = string.join (result, '')
if result == expected_result:
print "ok %d (%s)" % (count, description)
else:
print "not ok %d (%s):" % (count, description)
print "** expected:"
print expected_result
print "** received:"
print result
filename = "test.txt"
out_file = open (filename, "w")
out_file.write (test_data)
out_file.close ()
in_file = TextFile (filename, strip_comments=0, skip_blanks=0,
lstrip_ws=0, rstrip_ws=0)
test_input (1, "no processing", in_file, result1)
in_file = TextFile (filename, strip_comments=1, skip_blanks=0,
lstrip_ws=0, rstrip_ws=0)
test_input (2, "strip comments", in_file, result2)
in_file = TextFile (filename, strip_comments=0, skip_blanks=1,
lstrip_ws=0, rstrip_ws=0)
test_input (3, "strip blanks", in_file, result3)
in_file = TextFile (filename)
test_input (4, "default processing", in_file, result4)
in_file = TextFile (filename, strip_comments=1, skip_blanks=1,
join_lines=1, rstrip_ws=1)
test_input (5, "full processing", in_file, result5)
os.remove (filename)
|
