1# -*- coding: utf-8 -*- 2"""Support for wildcard pattern matching in object inspection. 3 4Authors 5------- 6- Jörgen Stenarson <jorgen.stenarson@bostream.nu> 7- Thomas Kluyver 8""" 9 10#***************************************************************************** 11# Copyright (C) 2005 Jörgen Stenarson <jorgen.stenarson@bostream.nu> 12# 13# Distributed under the terms of the BSD License. The full license is in 14# the file COPYING, distributed as part of this software. 15#***************************************************************************** 16 17import re 18import types 19 20from IPython.utils.dir2 import dir2 21from .py3compat import iteritems 22 23def create_typestr2type_dicts(dont_include_in_type2typestr=["lambda"]): 24 """Return dictionaries mapping lower case typename (e.g. 'tuple') to type 25 objects from the types package, and vice versa.""" 26 typenamelist = [tname for tname in dir(types) if tname.endswith("Type")] 27 typestr2type, type2typestr = {}, {} 28 29 for tname in typenamelist: 30 name = tname[:-4].lower() # Cut 'Type' off the end of the name 31 obj = getattr(types, tname) 32 typestr2type[name] = obj 33 if name not in dont_include_in_type2typestr: 34 type2typestr[obj] = name 35 return typestr2type, type2typestr 36 37typestr2type, type2typestr = create_typestr2type_dicts() 38 39def is_type(obj, typestr_or_type): 40 """is_type(obj, typestr_or_type) verifies if obj is of a certain type. It 41 can take strings or actual python types for the second argument, i.e. 42 'tuple'<->TupleType. 'all' matches all types. 43 44 TODO: Should be extended for choosing more than one type.""" 45 if typestr_or_type == "all": 46 return True 47 if type(typestr_or_type) == type: 48 test_type = typestr_or_type 49 else: 50 test_type = typestr2type.get(typestr_or_type, False) 51 if test_type: 52 return isinstance(obj, test_type) 53 return False 54 55def show_hidden(str, show_all=False): 56 """Return true for strings starting with single _ if show_all is true.""" 57 return show_all or str.startswith("__") or not str.startswith("_") 58 59def dict_dir(obj): 60 """Produce a dictionary of an object's attributes. Builds on dir2 by 61 checking that a getattr() call actually succeeds.""" 62 ns = {} 63 for key in dir2(obj): 64 # This seemingly unnecessary try/except is actually needed 65 # because there is code out there with metaclasses that 66 # create 'write only' attributes, where a getattr() call 67 # will fail even if the attribute appears listed in the 68 # object's dictionary. Properties can actually do the same 69 # thing. In particular, Traits use this pattern 70 try: 71 ns[key] = getattr(obj, key) 72 except AttributeError: 73 pass 74 return ns 75 76def filter_ns(ns, name_pattern="*", type_pattern="all", ignore_case=True, 77 show_all=True): 78 """Filter a namespace dictionary by name pattern and item type.""" 79 pattern = name_pattern.replace("*",".*").replace("?",".") 80 if ignore_case: 81 reg = re.compile(pattern+"$", re.I) 82 else: 83 reg = re.compile(pattern+"$") 84 85 # Check each one matches regex; shouldn't be hidden; of correct type. 86 return dict((key,obj) for key, obj in iteritems(ns) if reg.match(key) \ 87 and show_hidden(key, show_all) \ 88 and is_type(obj, type_pattern) ) 89 90def list_namespace(namespace, type_pattern, filter, ignore_case=False, show_all=False): 91 """Return dictionary of all objects in a namespace dictionary that match 92 type_pattern and filter.""" 93 pattern_list=filter.split(".") 94 if len(pattern_list) == 1: 95 return filter_ns(namespace, name_pattern=pattern_list[0], 96 type_pattern=type_pattern, 97 ignore_case=ignore_case, show_all=show_all) 98 else: 99 # This is where we can change if all objects should be searched or 100 # only modules. Just change the type_pattern to module to search only 101 # modules 102 filtered = filter_ns(namespace, name_pattern=pattern_list[0], 103 type_pattern="all", 104 ignore_case=ignore_case, show_all=show_all) 105 results = {} 106 for name, obj in iteritems(filtered): 107 ns = list_namespace(dict_dir(obj), type_pattern, 108 ".".join(pattern_list[1:]), 109 ignore_case=ignore_case, show_all=show_all) 110 for inner_name, inner_obj in iteritems(ns): 111 results["%s.%s"%(name,inner_name)] = inner_obj 112 return results 113