Python code coverage for Lib/fileinput.py

#	count	content
1	n/a	"""Helper class to quickly write a loop over all standard input files.
2	n/a
3	n/a	Typical use is:
4	n/a
5	n/a	import fileinput
6	n/a	for line in fileinput.input():
7	n/a	process(line)
8	n/a
9	n/a	This iterates over the lines of all files listed in sys.argv[1:],
10	n/a	defaulting to sys.stdin if the list is empty. If a filename is '-' it
11	n/a	is also replaced by sys.stdin. To specify an alternative list of
12	n/a	filenames, pass it as the argument to input(). A single file name is
13	n/a	also allowed.
14	n/a
15	n/a	Functions filename(), lineno() return the filename and cumulative line
16	n/a	number of the line that has just been read; filelineno() returns its
17	n/a	line number in the current file; isfirstline() returns true iff the
18	n/a	line just read is the first line of its file; isstdin() returns true
19	n/a	iff the line was read from sys.stdin. Function nextfile() closes the
20	n/a	current file so that the next iteration will read the first line from
21	n/a	the next file (if any); lines not read from the file will not count
22	n/a	towards the cumulative line count; the filename is not changed until
23	n/a	after the first line of the next file has been read. Function close()
24	n/a	closes the sequence.
25	n/a
26	n/a	Before any lines have been read, filename() returns None and both line
27	n/a	numbers are zero; nextfile() has no effect. After all lines have been
28	n/a	read, filename() and the line number functions return the values
29	n/a	pertaining to the last line read; nextfile() has no effect.
30	n/a
31	n/a	All files are opened in text mode by default, you can override this by
32	n/a	setting the mode parameter to input() or FileInput.__init__().
33	n/a	If an I/O error occurs during opening or reading a file, the OSError
34	n/a	exception is raised.
35	n/a
36	n/a	If sys.stdin is used more than once, the second and further use will
37	n/a	return no lines, except perhaps for interactive use, or if it has been
38	n/a	explicitly reset (e.g. using sys.stdin.seek(0)).
39	n/a
40	n/a	Empty files are opened and immediately closed; the only time their
41	n/a	presence in the list of filenames is noticeable at all is when the
42	n/a	last file opened is empty.
43	n/a
44	n/a	It is possible that the last line of a file doesn't end in a newline
45	n/a	character; otherwise lines are returned including the trailing
46	n/a	newline.
47	n/a
48	n/a	Class FileInput is the implementation; its methods filename(),
49	n/a	lineno(), fileline(), isfirstline(), isstdin(), nextfile() and close()
50	n/a	correspond to the functions in the module. In addition it has a
51	n/a	readline() method which returns the next input line, and a
52	n/a	__getitem__() method which implements the sequence behavior. The
53	n/a	sequence must be accessed in strictly sequential order; sequence
54	n/a	access and readline() cannot be mixed.
55	n/a
56	n/a	Optional in-place filtering: if the keyword argument inplace=1 is
57	n/a	passed to input() or to the FileInput constructor, the file is moved
58	n/a	to a backup file and standard output is directed to the input file.
59	n/a	This makes it possible to write a filter that rewrites its input file
60	n/a	in place. If the keyword argument backup=".<some extension>" is also
61	n/a	given, it specifies the extension for the backup file, and the backup
62	n/a	file remains around; by default, the extension is ".bak" and it is
63	n/a	deleted when the output file is closed. In-place filtering is
64	n/a	disabled when standard input is read. XXX The current implementation
65	n/a	does not work for MS-DOS 8+3 filesystems.
66	n/a
67	n/a	XXX Possible additions:
68	n/a
69	n/a	- optional getopt argument processing
70	n/a	- isatty()
71	n/a	- read(), read(size), even readlines()
72	n/a
73	n/a	"""
74	n/a
75	n/a	import sys, os
76	n/a
77	n/a	__all__ = ["input", "close", "nextfile", "filename", "lineno", "filelineno",
78	n/a	"fileno", "isfirstline", "isstdin", "FileInput", "hook_compressed",
79	n/a	"hook_encoded"]
80	n/a
81	n/a	_state = None
82	n/a
83	n/a	def input(files=None, inplace=False, backup="", bufsize=0,
84	n/a	mode="r", openhook=None):
85	n/a	"""Return an instance of the FileInput class, which can be iterated.
86	n/a
87	n/a	The parameters are passed to the constructor of the FileInput class.
88	n/a	The returned instance, in addition to being an iterator,
89	n/a	keeps global state for the functions of this module,.
90	n/a	"""
91	n/a	global _state
92	n/a	if _state and _state._file:
93	n/a	raise RuntimeError("input() already active")
94	n/a	_state = FileInput(files, inplace, backup, bufsize, mode, openhook)
95	n/a	return _state
96	n/a
97	n/a	def close():
98	n/a	"""Close the sequence."""
99	n/a	global _state
100	n/a	state = _state
101	n/a	_state = None
102	n/a	if state:
103	n/a	state.close()
104	n/a
105	n/a	def nextfile():
106	n/a	"""
107	n/a	Close the current file so that the next iteration will read the first
108	n/a	line from the next file (if any); lines not read from the file will
109	n/a	not count towards the cumulative line count. The filename is not
110	n/a	changed until after the first line of the next file has been read.
111	n/a	Before the first line has been read, this function has no effect;
112	n/a	it cannot be used to skip the first file. After the last line of the
113	n/a	last file has been read, this function has no effect.
114	n/a	"""
115	n/a	if not _state:
116	n/a	raise RuntimeError("no active input()")
117	n/a	return _state.nextfile()
118	n/a
119	n/a	def filename():
120	n/a	"""
121	n/a	Return the name of the file currently being read.
122	n/a	Before the first line has been read, returns None.
123	n/a	"""
124	n/a	if not _state:
125	n/a	raise RuntimeError("no active input()")
126	n/a	return _state.filename()
127	n/a
128	n/a	def lineno():
129	n/a	"""
130	n/a	Return the cumulative line number of the line that has just been read.
131	n/a	Before the first line has been read, returns 0. After the last line
132	n/a	of the last file has been read, returns the line number of that line.
133	n/a	"""
134	n/a	if not _state:
135	n/a	raise RuntimeError("no active input()")
136	n/a	return _state.lineno()
137	n/a
138	n/a	def filelineno():
139	n/a	"""
140	n/a	Return the line number in the current file. Before the first line
141	n/a	has been read, returns 0. After the last line of the last file has
142	n/a	been read, returns the line number of that line within the file.
143	n/a	"""
144	n/a	if not _state:
145	n/a	raise RuntimeError("no active input()")
146	n/a	return _state.filelineno()
147	n/a
148	n/a	def fileno():
149	n/a	"""
150	n/a	Return the file number of the current file. When no file is currently
151	n/a	opened, returns -1.
152	n/a	"""
153	n/a	if not _state:
154	n/a	raise RuntimeError("no active input()")
155	n/a	return _state.fileno()
156	n/a
157	n/a	def isfirstline():
158	n/a	"""
159	n/a	Returns true the line just read is the first line of its file,
160	n/a	otherwise returns false.
161	n/a	"""
162	n/a	if not _state:
163	n/a	raise RuntimeError("no active input()")
164	n/a	return _state.isfirstline()
165	n/a
166	n/a	def isstdin():
167	n/a	"""
168	n/a	Returns true if the last line was read from sys.stdin,
169	n/a	otherwise returns false.
170	n/a	"""
171	n/a	if not _state:
172	n/a	raise RuntimeError("no active input()")
173	n/a	return _state.isstdin()
174	n/a
175	n/a	class FileInput:
176	n/a	"""FileInput([files[, inplace[, backup[, bufsize, [, mode[, openhook]]]]]])
177	n/a
178	n/a	Class FileInput is the implementation of the module; its methods
179	n/a	filename(), lineno(), fileline(), isfirstline(), isstdin(), fileno(),
180	n/a	nextfile() and close() correspond to the functions of the same name
181	n/a	in the module.
182	n/a	In addition it has a readline() method which returns the next
183	n/a	input line, and a __getitem__() method which implements the
184	n/a	sequence behavior. The sequence must be accessed in strictly
185	n/a	sequential order; random access and readline() cannot be mixed.
186	n/a	"""
187	n/a
188	n/a	def __init__(self, files=None, inplace=False, backup="", bufsize=0,
189	n/a	mode="r", openhook=None):
190	n/a	if isinstance(files, str):
191	n/a	files = (files,)
192	n/a	else:
193	n/a	if files is None:
194	n/a	files = sys.argv[1:]
195	n/a	if not files:
196	n/a	files = ('-',)
197	n/a	else:
198	n/a	files = tuple(files)
199	n/a	self._files = files
200	n/a	self._inplace = inplace
201	n/a	self._backup = backup
202	n/a	if bufsize:
203	n/a	import warnings
204	n/a	warnings.warn('bufsize is deprecated and ignored',
205	n/a	DeprecationWarning, stacklevel=2)
206	n/a	self._savestdout = None
207	n/a	self._output = None
208	n/a	self._filename = None
209	n/a	self._startlineno = 0
210	n/a	self._filelineno = 0
211	n/a	self._file = None
212	n/a	self._isstdin = False
213	n/a	self._backupfilename = None
214	n/a	# restrict mode argument to reading modes
215	n/a	if mode not in ('r', 'rU', 'U', 'rb'):
216	n/a	raise ValueError("FileInput opening mode must be one of "
217	n/a	"'r', 'rU', 'U' and 'rb'")
218	n/a	if 'U' in mode:
219	n/a	import warnings
220	n/a	warnings.warn("'U' mode is deprecated",
221	n/a	DeprecationWarning, 2)
222	n/a	self._mode = mode
223	n/a	if openhook:
224	n/a	if inplace:
225	n/a	raise ValueError("FileInput cannot use an opening hook in inplace mode")
226	n/a	if not callable(openhook):
227	n/a	raise ValueError("FileInput openhook must be callable")
228	n/a	self._openhook = openhook
229	n/a
230	n/a	def __del__(self):
231	n/a	self.close()
232	n/a
233	n/a	def close(self):
234	n/a	try:
235	n/a	self.nextfile()
236	n/a	finally:
237	n/a	self._files = ()
238	n/a
239	n/a	def __enter__(self):
240	n/a	return self
241	n/a
242	n/a	def __exit__(self, type, value, traceback):
243	n/a	self.close()
244	n/a
245	n/a	def __iter__(self):
246	n/a	return self
247	n/a
248	n/a	def __next__(self):
249	n/a	while True:
250	n/a	line = self._readline()
251	n/a	if line:
252	n/a	self._filelineno += 1
253	n/a	return line
254	n/a	if not self._file:
255	n/a	raise StopIteration
256	n/a	self.nextfile()
257	n/a	# repeat with next file
258	n/a
259	n/a	def __getitem__(self, i):
260	n/a	if i != self.lineno():
261	n/a	raise RuntimeError("accessing lines out of order")
262	n/a	try:
263	n/a	return self.__next__()
264	n/a	except StopIteration:
265	n/a	raise IndexError("end of input reached")
266	n/a
267	n/a	def nextfile(self):
268	n/a	savestdout = self._savestdout
269	n/a	self._savestdout = None
270	n/a	if savestdout:
271	n/a	sys.stdout = savestdout
272	n/a
273	n/a	output = self._output
274	n/a	self._output = None
275	n/a	try:
276	n/a	if output:
277	n/a	output.close()
278	n/a	finally:
279	n/a	file = self._file
280	n/a	self._file = None
281	n/a	try:
282	n/a	del self._readline # restore FileInput._readline
283	n/a	except AttributeError:
284	n/a	pass
285	n/a	try:
286	n/a	if file and not self._isstdin:
287	n/a	file.close()
288	n/a	finally:
289	n/a	backupfilename = self._backupfilename
290	n/a	self._backupfilename = None
291	n/a	if backupfilename and not self._backup:
292	n/a	try: os.unlink(backupfilename)
293	n/a	except OSError: pass
294	n/a
295	n/a	self._isstdin = False
296	n/a
297	n/a	def readline(self):
298	n/a	while True:
299	n/a	line = self._readline()
300	n/a	if line:
301	n/a	self._filelineno += 1
302	n/a	return line
303	n/a	if not self._file:
304	n/a	return line
305	n/a	self.nextfile()
306	n/a	# repeat with next file
307	n/a
308	n/a	def _readline(self):
309	n/a	if not self._files:
310	n/a	if 'b' in self._mode:
311	n/a	return b''
312	n/a	else:
313	n/a	return ''
314	n/a	self._filename = self._files[0]
315	n/a	self._files = self._files[1:]
316	n/a	self._startlineno = self.lineno()
317	n/a	self._filelineno = 0
318	n/a	self._file = None
319	n/a	self._isstdin = False
320	n/a	self._backupfilename = 0
321	n/a	if self._filename == '-':
322	n/a	self._filename = '<stdin>'
323	n/a	if 'b' in self._mode:
324	n/a	self._file = getattr(sys.stdin, 'buffer', sys.stdin)
325	n/a	else:
326	n/a	self._file = sys.stdin
327	n/a	self._isstdin = True
328	n/a	else:
329	n/a	if self._inplace:
330	n/a	self._backupfilename = (
331	n/a	self._filename + (self._backup or ".bak"))
332	n/a	try:
333	n/a	os.unlink(self._backupfilename)
334	n/a	except OSError:
335	n/a	pass
336	n/a	# The next few lines may raise OSError
337	n/a	os.rename(self._filename, self._backupfilename)
338	n/a	self._file = open(self._backupfilename, self._mode)
339	n/a	try:
340	n/a	perm = os.fstat(self._file.fileno()).st_mode
341	n/a	except OSError:
342	n/a	self._output = open(self._filename, "w")
343	n/a	else:
344	n/a	mode = os.O_CREAT \| os.O_WRONLY \| os.O_TRUNC
345	n/a	if hasattr(os, 'O_BINARY'):
346	n/a	mode \|= os.O_BINARY
347	n/a
348	n/a	fd = os.open(self._filename, mode, perm)
349	n/a	self._output = os.fdopen(fd, "w")
350	n/a	try:
351	n/a	if hasattr(os, 'chmod'):
352	n/a	os.chmod(self._filename, perm)
353	n/a	except OSError:
354	n/a	pass
355	n/a	self._savestdout = sys.stdout
356	n/a	sys.stdout = self._output
357	n/a	else:
358	n/a	# This may raise OSError
359	n/a	if self._openhook:
360	n/a	self._file = self._openhook(self._filename, self._mode)
361	n/a	else:
362	n/a	self._file = open(self._filename, self._mode)
363	n/a	self._readline = self._file.readline # hide FileInput._readline
364	n/a	return self._readline()
365	n/a
366	n/a	def filename(self):
367	n/a	return self._filename
368	n/a
369	n/a	def lineno(self):
370	n/a	return self._startlineno + self._filelineno
371	n/a
372	n/a	def filelineno(self):
373	n/a	return self._filelineno
374	n/a
375	n/a	def fileno(self):
376	n/a	if self._file:
377	n/a	try:
378	n/a	return self._file.fileno()
379	n/a	except ValueError:
380	n/a	return -1
381	n/a	else:
382	n/a	return -1
383	n/a
384	n/a	def isfirstline(self):
385	n/a	return self._filelineno == 1
386	n/a
387	n/a	def isstdin(self):
388	n/a	return self._isstdin
389	n/a
390	n/a
391	n/a	def hook_compressed(filename, mode):
392	n/a	ext = os.path.splitext(filename)[1]
393	n/a	if ext == '.gz':
394	n/a	import gzip
395	n/a	return gzip.open(filename, mode)
396	n/a	elif ext == '.bz2':
397	n/a	import bz2
398	n/a	return bz2.BZ2File(filename, mode)
399	n/a	else:
400	n/a	return open(filename, mode)
401	n/a
402	n/a
403	n/a	def hook_encoded(encoding, errors=None):
404	n/a	def openhook(filename, mode):
405	n/a	return open(filename, mode, encoding=encoding, errors=errors)
406	n/a	return openhook
407	n/a
408	n/a
409	n/a	def _test():
410	n/a	import getopt
411	n/a	inplace = False
412	n/a	backup = False
413	n/a	opts, args = getopt.getopt(sys.argv[1:], "ib:")
414	n/a	for o, a in opts:
415	n/a	if o == '-i': inplace = True
416	n/a	if o == '-b': backup = a
417	n/a	for line in input(args, inplace=inplace, backup=backup):
418	n/a	if line[-1:] == '\n': line = line[:-1]
419	n/a	if line[-1:] == '\r': line = line[:-1]
420	n/a	print("%d: %s[%d]%s %s" % (lineno(), filename(), filelineno(),
421	n/a	isfirstline() and "*" or "", line))
422	n/a	print("%d: %s[%d]" % (lineno(), filename(), filelineno()))
423	n/a
424	n/a	if __name__ == '__main__':
425	n/a	_test()