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author | Devtools Arcadia <arcadia-devtools@yandex-team.ru> | 2022-02-07 18:08:42 +0300 |
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committer | Devtools Arcadia <arcadia-devtools@mous.vla.yp-c.yandex.net> | 2022-02-07 18:08:42 +0300 |
commit | 1110808a9d39d4b808aef724c861a2e1a38d2a69 (patch) | |
tree | e26c9fed0de5d9873cce7e00bc214573dc2195b7 /contrib/tools/python3/src/Lib/rlcompleter.py | |
download | ydb-1110808a9d39d4b808aef724c861a2e1a38d2a69.tar.gz |
intermediate changes
ref:cde9a383711a11544ce7e107a78147fb96cc4029
Diffstat (limited to 'contrib/tools/python3/src/Lib/rlcompleter.py')
-rw-r--r-- | contrib/tools/python3/src/Lib/rlcompleter.py | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/contrib/tools/python3/src/Lib/rlcompleter.py b/contrib/tools/python3/src/Lib/rlcompleter.py new file mode 100644 index 0000000000..923f5c0541 --- /dev/null +++ b/contrib/tools/python3/src/Lib/rlcompleter.py @@ -0,0 +1,212 @@ +"""Word completion for GNU readline. + +The completer completes keywords, built-ins and globals in a selectable +namespace (which defaults to __main__); when completing NAME.NAME..., it +evaluates (!) the expression up to the last dot and completes its attributes. + +It's very cool to do "import sys" type "sys.", hit the completion key (twice), +and see the list of names defined by the sys module! + +Tip: to use the tab key as the completion key, call + + readline.parse_and_bind("tab: complete") + +Notes: + +- Exceptions raised by the completer function are *ignored* (and generally cause + the completion to fail). This is a feature -- since readline sets the tty + device in raw (or cbreak) mode, printing a traceback wouldn't work well + without some complicated hoopla to save, reset and restore the tty state. + +- The evaluation of the NAME.NAME... form may cause arbitrary application + defined code to be executed if an object with a __getattr__ hook is found. + Since it is the responsibility of the application (or the user) to enable this + feature, I consider this an acceptable risk. More complicated expressions + (e.g. function calls or indexing operations) are *not* evaluated. + +- When the original stdin is not a tty device, GNU readline is never + used, and this module (and the readline module) are silently inactive. + +""" + +import atexit +import builtins +import __main__ + +__all__ = ["Completer"] + +class Completer: + def __init__(self, namespace = None): + """Create a new completer for the command line. + + Completer([namespace]) -> completer instance. + + If unspecified, the default namespace where completions are performed + is __main__ (technically, __main__.__dict__). Namespaces should be + given as dictionaries. + + Completer instances should be used as the completion mechanism of + readline via the set_completer() call: + + readline.set_completer(Completer(my_namespace).complete) + """ + + if namespace and not isinstance(namespace, dict): + raise TypeError('namespace must be a dictionary') + + # Don't bind to namespace quite yet, but flag whether the user wants a + # specific namespace or to use __main__.__dict__. This will allow us + # to bind to __main__.__dict__ at completion time, not now. + if namespace is None: + self.use_main_ns = 1 + else: + self.use_main_ns = 0 + self.namespace = namespace + + def complete(self, text, state): + """Return the next possible completion for 'text'. + + This is called successively with state == 0, 1, 2, ... until it + returns None. The completion should begin with 'text'. + + """ + if self.use_main_ns: + self.namespace = __main__.__dict__ + + if not text.strip(): + if state == 0: + if _readline_available: + readline.insert_text('\t') + readline.redisplay() + return '' + else: + return '\t' + else: + return None + + if state == 0: + if "." in text: + self.matches = self.attr_matches(text) + else: + self.matches = self.global_matches(text) + try: + return self.matches[state] + except IndexError: + return None + + def _callable_postfix(self, val, word): + if callable(val): + word = word + "(" + return word + + def global_matches(self, text): + """Compute matches when text is a simple name. + + Return a list of all keywords, built-in functions and names currently + defined in self.namespace that match. + + """ + import keyword + matches = [] + seen = {"__builtins__"} + n = len(text) + for word in keyword.kwlist: + if word[:n] == text: + seen.add(word) + if word in {'finally', 'try'}: + word = word + ':' + elif word not in {'False', 'None', 'True', + 'break', 'continue', 'pass', + 'else'}: + word = word + ' ' + matches.append(word) + for nspace in [self.namespace, builtins.__dict__]: + for word, val in nspace.items(): + if word[:n] == text and word not in seen: + seen.add(word) + matches.append(self._callable_postfix(val, word)) + return matches + + def attr_matches(self, text): + """Compute matches when text contains a dot. + + Assuming the text is of the form NAME.NAME....[NAME], and is + evaluable in self.namespace, it will be evaluated and its attributes + (as revealed by dir()) are used as possible completions. (For class + instances, class members are also considered.) + + WARNING: this can still invoke arbitrary C code, if an object + with a __getattr__ hook is evaluated. + + """ + import re + m = re.match(r"(\w+(\.\w+)*)\.(\w*)", text) + if not m: + return [] + expr, attr = m.group(1, 3) + try: + thisobject = eval(expr, self.namespace) + except Exception: + return [] + + # get the content of the object, except __builtins__ + words = set(dir(thisobject)) + words.discard("__builtins__") + + if hasattr(thisobject, '__class__'): + words.add('__class__') + words.update(get_class_members(thisobject.__class__)) + matches = [] + n = len(attr) + if attr == '': + noprefix = '_' + elif attr == '_': + noprefix = '__' + else: + noprefix = None + while True: + for word in words: + if (word[:n] == attr and + not (noprefix and word[:n+1] == noprefix)): + match = "%s.%s" % (expr, word) + if isinstance(getattr(type(thisobject), word, None), + property): + # bpo-44752: thisobject.word is a method decorated by + # `@property`. What follows applies a postfix if + # thisobject.word is callable, but know we know that + # this is not callable (because it is a property). + # Also, getattr(thisobject, word) will evaluate the + # property method, which is not desirable. + matches.append(match) + continue + if (value := getattr(thisobject, word, None)) is not None: + matches.append(self._callable_postfix(value, match)) + else: + matches.append(match) + if matches or not noprefix: + break + if noprefix == '_': + noprefix = '__' + else: + noprefix = None + matches.sort() + return matches + +def get_class_members(klass): + ret = dir(klass) + if hasattr(klass,'__bases__'): + for base in klass.__bases__: + ret = ret + get_class_members(base) + return ret + +try: + import readline +except ImportError: + _readline_available = False +else: + readline.set_completer(Completer().complete) + # Release references early at shutdown (the readline module's + # contents are quasi-immortal, and the completer function holds a + # reference to globals). + atexit.register(lambda: readline.set_completer(None)) + _readline_available = True |