1
"""A generic class to build line-oriented command interpreters.
3
Interpreters constructed with this class obey the following conventions:
5
1. End of file on input is processed as the command 'EOF'.
6
2. A command is parsed out of each line by collecting the prefix composed
7
of characters in the identchars member.
8
3. A command `foo' is dispatched to a method 'do_foo()'; the do_ method
9
is passed a single argument consisting of the remainder of the line.
10
4. Typing an empty line repeats the last command. (Actually, it calls the
11
method `emptyline', which may be overridden in a subclass.)
12
5. There is a predefined `help' method. Given an argument `topic', it
13
calls the command `help_topic'. With no arguments, it lists all topics
14
with defined help_ functions, broken into up to three topics; documented
15
commands, miscellaneous help topics, and undocumented commands.
16
6. The command '?' is a synonym for `help'. The command '!' is a synonym
17
for `shell', if a do_shell method exists.
18
7. If completion is enabled, completing commands will be done automatically,
19
and completing of commands args is done by calling complete_foo() with
20
arguments text, line, begidx, endidx. text is string we are matching
21
against, all returned matches must begin with it. line is the current
22
input line (lstripped), begidx and endidx are the beginning and end
23
indexes of the text being matched, which could be used to provide
24
different completion depending upon which position the argument is in.
26
The `default' method may be overridden to intercept commands for which there
29
The `completedefault' method may be overridden to intercept completions for
30
commands that have no complete_ method.
32
The data member `self.ruler' sets the character used to draw separator lines
33
in the help messages. If empty, no ruler line is drawn. It defaults to "=".
35
If the value of `self.intro' is nonempty when the cmdloop method is called,
36
it is printed out on interpreter startup. This value may be overridden
37
via an optional argument to the cmdloop() method.
39
The data members `self.doc_header', `self.misc_header', and
40
`self.undoc_header' set the headers used for the help function's
41
listings of documented functions, miscellaneous topics, and undocumented
42
functions respectively.
44
These interpreters use raw_input; thus, if the readline module is loaded,
45
they automatically support Emacs-like command history and editing features.
53
IDENTCHARS = string.ascii_letters + string.digits + '_'
56
"""A simple framework for writing line-oriented command interpreters.
58
These are often useful for test harnesses, administrative tools, and
59
prototypes that will later be wrapped in a more sophisticated interface.
61
A Cmd instance or subclass instance is a line-oriented interpreter
62
framework. There is no good reason to instantiate Cmd itself; rather,
63
it's useful as a superclass of an interpreter class you define yourself
64
in order to inherit Cmd's methods and encapsulate action methods.
68
identchars = IDENTCHARS
73
doc_header = "Documented commands (type help <topic>):"
74
misc_header = "Miscellaneous help topics:"
75
undoc_header = "Undocumented commands:"
76
nohelp = "*** No help on %s"
79
def __init__(self, completekey='tab', stdin=None, stdout=None):
80
"""Instantiate a line-oriented interpreter framework.
82
The optional argument 'completekey' is the readline name of a
83
completion key; it defaults to the Tab key. If completekey is
84
not None and the readline module is available, command completion
85
is done automatically. The optional arguments stdin and stdout
86
specify alternate input and output file objects; if not specified,
87
sys.stdin and sys.stdout are used.
94
self.stdin = sys.stdin
95
if stdout is not None:
98
self.stdout = sys.stdout
100
self.completekey = completekey
102
def cmdloop(self, intro=None):
103
"""Repeatedly issue a prompt, accept input, parse an initial prefix
104
off the received input, and dispatch to action methods, passing them
105
the remainder of the line as argument.
110
if self.use_rawinput and self.completekey:
113
self.old_completer = readline.get_completer()
114
readline.set_completer(self.complete)
115
readline.parse_and_bind(self.completekey+": complete")
119
if intro is not None:
122
self.stdout.write(str(self.intro)+"\n")
126
line = self.cmdqueue.pop(0)
128
if self.use_rawinput:
130
line = raw_input(self.prompt)
134
self.stdout.write(self.prompt)
136
line = self.stdin.readline()
140
line = line.rstrip('\r\n')
141
line = self.precmd(line)
142
stop = self.onecmd(line)
143
stop = self.postcmd(stop, line)
146
if self.use_rawinput and self.completekey:
149
readline.set_completer(self.old_completer)
154
def precmd(self, line):
155
"""Hook method executed just before the command line is
156
interpreted, but after the input prompt is generated and issued.
161
def postcmd(self, stop, line):
162
"""Hook method executed just after a command dispatch is finished."""
166
"""Hook method executed once when the cmdloop() method is called."""
170
"""Hook method executed once when the cmdloop() method is about to
176
def parseline(self, line):
177
"""Parse the line into a command name and a string containing
178
the arguments. Returns a tuple containing (command, args, line).
179
'command' and 'args' may be None if the line couldn't be parsed.
183
return None, None, line
185
line = 'help ' + line[1:]
187
if hasattr(self, 'do_shell'):
188
line = 'shell ' + line[1:]
190
return None, None, line
192
while i < n and line[i] in self.identchars: i = i+1
193
cmd, arg = line[:i], line[i:].strip()
194
return cmd, arg, line
196
def onecmd(self, line):
197
"""Interpret the argument as though it had been typed in response
200
This may be overridden, but should not normally need to be;
201
see the precmd() and postcmd() methods for useful execution hooks.
202
The return value is a flag indicating whether interpretation of
203
commands by the interpreter should stop.
206
cmd, arg, line = self.parseline(line)
208
return self.emptyline()
210
return self.default(line)
215
return self.default(line)
218
func = getattr(self, 'do_' + cmd)
219
except AttributeError:
220
return self.default(line)
224
"""Called when an empty line is entered in response to the prompt.
226
If this method is not overridden, it repeats the last nonempty
231
return self.onecmd(self.lastcmd)
233
def default(self, line):
234
"""Called on an input line when the command prefix is not recognized.
236
If this method is not overridden, it prints an error message and
240
self.stdout.write('*** Unknown syntax: %s\n'%line)
242
def completedefault(self, *ignored):
243
"""Method called to complete an input line when no command-specific
244
complete_*() method is available.
246
By default, it returns an empty list.
251
def completenames(self, text, *ignored):
253
return [a[3:] for a in self.get_names() if a.startswith(dotext)]
255
def complete(self, text, state):
256
"""Return the next possible completion for 'text'.
258
If a command has not been entered, then complete against command list.
259
Otherwise try to call complete_<command> to get list of completions.
263
origline = readline.get_line_buffer()
264
line = origline.lstrip()
265
stripped = len(origline) - len(line)
266
begidx = readline.get_begidx() - stripped
267
endidx = readline.get_endidx() - stripped
269
cmd, args, foo = self.parseline(line)
271
compfunc = self.completedefault
274
compfunc = getattr(self, 'complete_' + cmd)
275
except AttributeError:
276
compfunc = self.completedefault
278
compfunc = self.completenames
279
self.completion_matches = compfunc(text, line, begidx, endidx)
281
return self.completion_matches[state]
286
# This method used to pull in base class attributes
287
# at a time dir() didn't do it yet.
288
return dir(self.__class__)
290
def complete_help(self, *args):
291
commands = set(self.completenames(*args))
292
topics = set(a[5:] for a in self.get_names()
293
if a.startswith('help_' + args[0]))
294
return list(commands | topics)
296
def do_help(self, arg):
297
'List available commands with "help" or detailed help with "help cmd".'
299
# XXX check arg syntax
301
func = getattr(self, 'help_' + arg)
302
except AttributeError:
304
doc=getattr(self, 'do_' + arg).__doc__
306
self.stdout.write("%s\n"%str(doc))
308
except AttributeError:
310
self.stdout.write("%s\n"%str(self.nohelp % (arg,)))
314
names = self.get_names()
319
if name[:5] == 'help_':
322
# There can be duplicates if routines overridden
325
if name[:3] == 'do_':
333
elif getattr(self, name).__doc__:
336
cmds_undoc.append(cmd)
337
self.stdout.write("%s\n"%str(self.doc_leader))
338
self.print_topics(self.doc_header, cmds_doc, 15,80)
339
self.print_topics(self.misc_header, help.keys(),15,80)
340
self.print_topics(self.undoc_header, cmds_undoc, 15,80)
342
def print_topics(self, header, cmds, cmdlen, maxcol):
344
self.stdout.write("%s\n"%str(header))
346
self.stdout.write("%s\n"%str(self.ruler * len(header)))
347
self.columnize(cmds, maxcol-1)
348
self.stdout.write("\n")
350
def columnize(self, list, displaywidth=80):
351
"""Display a list of strings as a compact set of columns.
353
Each column is only as wide as necessary.
354
Columns are separated by two spaces (one was not legible enough).
357
self.stdout.write("<empty>\n")
359
nonstrings = [i for i in range(len(list))
360
if not isinstance(list[i], str)]
362
raise TypeError, ("list[i] not a string for i in %s" %
363
", ".join(map(str, nonstrings)))
366
self.stdout.write('%s\n'%str(list[0]))
368
# Try every row count from 1 upwards
369
for nrows in range(1, len(list)):
370
ncols = (size+nrows-1) // nrows
373
for col in range(ncols):
375
for row in range(nrows):
380
colwidth = max(colwidth, len(x))
381
colwidths.append(colwidth)
382
totwidth += colwidth + 2
383
if totwidth > displaywidth:
385
if totwidth <= displaywidth:
391
for row in range(nrows):
393
for col in range(ncols):
400
while texts and not texts[-1]:
402
for col in range(len(texts)):
403
texts[col] = texts[col].ljust(colwidths[col])
404
self.stdout.write("%s\n"%str(" ".join(texts)))
1
"""A generic class to build line-oriented command interpreters.
3
Interpreters constructed with this class obey the following conventions:
5
1. End of file on input is processed as the command 'EOF'.
6
2. A command is parsed out of each line by collecting the prefix composed
7
of characters in the identchars member.
8
3. A command `foo' is dispatched to a method 'do_foo()'; the do_ method
9
is passed a single argument consisting of the remainder of the line.
10
4. Typing an empty line repeats the last command. (Actually, it calls the
11
method `emptyline', which may be overridden in a subclass.)
12
5. There is a predefined `help' method. Given an argument `topic', it
13
calls the command `help_topic'. With no arguments, it lists all topics
14
with defined help_ functions, broken into up to three topics; documented
15
commands, miscellaneous help topics, and undocumented commands.
16
6. The command '?' is a synonym for `help'. The command '!' is a synonym
17
for `shell', if a do_shell method exists.
18
7. If completion is enabled, completing commands will be done automatically,
19
and completing of commands args is done by calling complete_foo() with
20
arguments text, line, begidx, endidx. text is string we are matching
21
against, all returned matches must begin with it. line is the current
22
input line (lstripped), begidx and endidx are the beginning and end
23
indexes of the text being matched, which could be used to provide
24
different completion depending upon which position the argument is in.
26
The `default' method may be overridden to intercept commands for which there
29
The `completedefault' method may be overridden to intercept completions for
30
commands that have no complete_ method.
32
The data member `self.ruler' sets the character used to draw separator lines
33
in the help messages. If empty, no ruler line is drawn. It defaults to "=".
35
If the value of `self.intro' is nonempty when the cmdloop method is called,
36
it is printed out on interpreter startup. This value may be overridden
37
via an optional argument to the cmdloop() method.
39
The data members `self.doc_header', `self.misc_header', and
40
`self.undoc_header' set the headers used for the help function's
41
listings of documented functions, miscellaneous topics, and undocumented
42
functions respectively.
44
These interpreters use raw_input; thus, if the readline module is loaded,
45
they automatically support Emacs-like command history and editing features.
53
IDENTCHARS = string.ascii_letters + string.digits + '_'
56
"""A simple framework for writing line-oriented command interpreters.
58
These are often useful for test harnesses, administrative tools, and
59
prototypes that will later be wrapped in a more sophisticated interface.
61
A Cmd instance or subclass instance is a line-oriented interpreter
62
framework. There is no good reason to instantiate Cmd itself; rather,
63
it's useful as a superclass of an interpreter class you define yourself
64
in order to inherit Cmd's methods and encapsulate action methods.
68
identchars = IDENTCHARS
73
doc_header = "Documented commands (type help <topic>):"
74
misc_header = "Miscellaneous help topics:"
75
undoc_header = "Undocumented commands:"
76
nohelp = "*** No help on %s"
79
def __init__(self, completekey='tab', stdin=None, stdout=None):
80
"""Instantiate a line-oriented interpreter framework.
82
The optional argument 'completekey' is the readline name of a
83
completion key; it defaults to the Tab key. If completekey is
84
not None and the readline module is available, command completion
85
is done automatically. The optional arguments stdin and stdout
86
specify alternate input and output file objects; if not specified,
87
sys.stdin and sys.stdout are used.
94
self.stdin = sys.stdin
95
if stdout is not None:
98
self.stdout = sys.stdout
100
self.completekey = completekey
102
def cmdloop(self, intro=None):
103
"""Repeatedly issue a prompt, accept input, parse an initial prefix
104
off the received input, and dispatch to action methods, passing them
105
the remainder of the line as argument.
110
if self.use_rawinput and self.completekey:
113
self.old_completer = readline.get_completer()
114
readline.set_completer(self.complete)
115
readline.parse_and_bind(self.completekey+": complete")
119
if intro is not None:
122
self.stdout.write(str(self.intro)+"\n")
126
line = self.cmdqueue.pop(0)
128
if self.use_rawinput:
130
line = raw_input(self.prompt)
134
self.stdout.write(self.prompt)
136
line = self.stdin.readline()
140
line = line.rstrip('\r\n')
141
line = self.precmd(line)
142
stop = self.onecmd(line)
143
stop = self.postcmd(stop, line)
146
if self.use_rawinput and self.completekey:
149
readline.set_completer(self.old_completer)
154
def precmd(self, line):
155
"""Hook method executed just before the command line is
156
interpreted, but after the input prompt is generated and issued.
161
def postcmd(self, stop, line):
162
"""Hook method executed just after a command dispatch is finished."""
166
"""Hook method executed once when the cmdloop() method is called."""
170
"""Hook method executed once when the cmdloop() method is about to
176
def parseline(self, line):
177
"""Parse the line into a command name and a string containing
178
the arguments. Returns a tuple containing (command, args, line).
179
'command' and 'args' may be None if the line couldn't be parsed.
183
return None, None, line
185
line = 'help ' + line[1:]
187
if hasattr(self, 'do_shell'):
188
line = 'shell ' + line[1:]
190
return None, None, line
192
while i < n and line[i] in self.identchars: i = i+1
193
cmd, arg = line[:i], line[i:].strip()
194
return cmd, arg, line
196
def onecmd(self, line):
197
"""Interpret the argument as though it had been typed in response
200
This may be overridden, but should not normally need to be;
201
see the precmd() and postcmd() methods for useful execution hooks.
202
The return value is a flag indicating whether interpretation of
203
commands by the interpreter should stop.
206
cmd, arg, line = self.parseline(line)
208
return self.emptyline()
210
return self.default(line)
215
return self.default(line)
218
func = getattr(self, 'do_' + cmd)
219
except AttributeError:
220
return self.default(line)
224
"""Called when an empty line is entered in response to the prompt.
226
If this method is not overridden, it repeats the last nonempty
231
return self.onecmd(self.lastcmd)
233
def default(self, line):
234
"""Called on an input line when the command prefix is not recognized.
236
If this method is not overridden, it prints an error message and
240
self.stdout.write('*** Unknown syntax: %s\n'%line)
242
def completedefault(self, *ignored):
243
"""Method called to complete an input line when no command-specific
244
complete_*() method is available.
246
By default, it returns an empty list.
251
def completenames(self, text, *ignored):
253
return [a[3:] for a in self.get_names() if a.startswith(dotext)]
255
def complete(self, text, state):
256
"""Return the next possible completion for 'text'.
258
If a command has not been entered, then complete against command list.
259
Otherwise try to call complete_<command> to get list of completions.
263
origline = readline.get_line_buffer()
264
line = origline.lstrip()
265
stripped = len(origline) - len(line)
266
begidx = readline.get_begidx() - stripped
267
endidx = readline.get_endidx() - stripped
269
cmd, args, foo = self.parseline(line)
271
compfunc = self.completedefault
274
compfunc = getattr(self, 'complete_' + cmd)
275
except AttributeError:
276
compfunc = self.completedefault
278
compfunc = self.completenames
279
self.completion_matches = compfunc(text, line, begidx, endidx)
281
return self.completion_matches[state]
286
# This method used to pull in base class attributes
287
# at a time dir() didn't do it yet.
288
return dir(self.__class__)
290
def complete_help(self, *args):
291
commands = set(self.completenames(*args))
292
topics = set(a[5:] for a in self.get_names()
293
if a.startswith('help_' + args[0]))
294
return list(commands | topics)
296
def do_help(self, arg):
297
'List available commands with "help" or detailed help with "help cmd".'
299
# XXX check arg syntax
301
func = getattr(self, 'help_' + arg)
302
except AttributeError:
304
doc=getattr(self, 'do_' + arg).__doc__
306
self.stdout.write("%s\n"%str(doc))
308
except AttributeError:
310
self.stdout.write("%s\n"%str(self.nohelp % (arg,)))
314
names = self.get_names()
319
if name[:5] == 'help_':
322
# There can be duplicates if routines overridden
325
if name[:3] == 'do_':
333
elif getattr(self, name).__doc__:
336
cmds_undoc.append(cmd)
337
self.stdout.write("%s\n"%str(self.doc_leader))
338
self.print_topics(self.doc_header, cmds_doc, 15,80)
339
self.print_topics(self.misc_header, help.keys(),15,80)
340
self.print_topics(self.undoc_header, cmds_undoc, 15,80)
342
def print_topics(self, header, cmds, cmdlen, maxcol):
344
self.stdout.write("%s\n"%str(header))
346
self.stdout.write("%s\n"%str(self.ruler * len(header)))
347
self.columnize(cmds, maxcol-1)
348
self.stdout.write("\n")
350
def columnize(self, list, displaywidth=80):
351
"""Display a list of strings as a compact set of columns.
353
Each column is only as wide as necessary.
354
Columns are separated by two spaces (one was not legible enough).
357
self.stdout.write("<empty>\n")
359
nonstrings = [i for i in range(len(list))
360
if not isinstance(list[i], str)]
362
raise TypeError, ("list[i] not a string for i in %s" %
363
", ".join(map(str, nonstrings)))
366
self.stdout.write('%s\n'%str(list[0]))
368
# Try every row count from 1 upwards
369
for nrows in range(1, len(list)):
370
ncols = (size+nrows-1) // nrows
373
for col in range(ncols):
375
for row in range(nrows):
380
colwidth = max(colwidth, len(x))
381
colwidths.append(colwidth)
382
totwidth += colwidth + 2
383
if totwidth > displaywidth:
385
if totwidth <= displaywidth:
391
for row in range(nrows):
393
for col in range(ncols):
400
while texts and not texts[-1]:
402
for col in range(len(texts)):
403
texts[col] = texts[col].ljust(colwidths[col])
404
self.stdout.write("%s\n"%str(" ".join(texts)))
added
removed
python/Lib/cmd.py
