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