"""Parse a Python file and retrieve classes and methods. Parse enough of a Python file to recognize class and method definitions and to find out the superclasses of a class. The interface consists of a single function: readmodule_ex(module [, path[, inpackage]]) module is the name of a Python module, path is an optional list of directories where the module is to be searched. If present, path is prepended to the system search path sys.path. (inpackage is used internally to search for a submodule of a package.) The return value is a dictionary. The keys of the dictionary are the names of the classes defined in the module (including classes that are defined via the from XXX import YYY construct). The values are class instances of the class Class defined here. A class is described by the class Class in this module. Instances of this class have the following instance variables: name -- the name of the class super -- a list of super classes (Class instances) methods -- a dictionary of methods file -- the file in which the class was defined lineno -- the line in the file on which the class statement occurred The dictionary of methods uses the method names as keys and the line numbers on which the method was defined as values. If the name of a super class is not recognized, the corresponding entry in the list of super classes is not a class instance but a string giving the name of the super class. Since import statements are recognized and imported modules are scanned as well, this shouldn't happen often. XXX describe the Function class. BUGS - Nested classes and functions can confuse it. PACKAGE RELATED BUGS - If you have a package and a module inside that or another package with the same name, module caching doesn't work properly since the key is the base name of the module/package. - The only entry that is returned when you readmodule a package is a __path__ whose value is a list which confuses certain class browsers. - When code does: from package import subpackage class MyClass(subpackage.SuperClass): ... It can't locate the parent. It probably needs to have the same hairy logic that the import locator already does. (This logic exists coded in Python in the freeze package.) """ import sys import imp import tokenize # Python tokenizer from token import NAME __all__ = ["readmodule"] _modules = {} # cache of modules we've seen # each Python class is represented by an instance of this class class Class: '''Class to represent a Python class.''' def __init__(self, module, name, super, file, lineno): self.module = module self.name = name if super is None: super = [] self.super = super self.methods = {} self.file = file self.lineno = lineno def _addmethod(self, name, lineno): self.methods[name] = lineno class Function(Class): '''Class to represent a top-level Python function''' def __init__(self, module, name, file, lineno): Class.__init__(self, module, name, None, file, lineno) def _addmethod(self, name, lineno): assert 0, "Function._addmethod() shouldn't be called" def readmodule(module, path=[], inpackage=False): '''Backwards compatible interface. Like readmodule_ex() but strips Function objects from the resulting dictionary.''' dict = readmodule_ex(module, path, inpackage) res = {} for key, value in dict.items(): if not isinstance(value, Function): res[key] = value return res def readmodule_ex(module, path=[], inpackage=False): '''Read a module file and return a dictionary of classes. Search for MODULE in PATH and sys.path, read and parse the module and return a dictionary with one entry for each class found in the module.''' dict = {} i = module.rfind('.') if i >= 0: # Dotted module name package = module[:i].strip() submodule = module[i+1:].strip() parent = readmodule_ex(package, path, inpackage) child = readmodule_ex(submodule, parent['__path__'], True) return child if module in _modules: # we've seen this module before... return _modules[module] if module in sys.builtin_module_names: # this is a built-in module _modules[module] = dict return dict # search the path for the module f = None if inpackage: try: f, file, (suff, mode, type) = \ imp.find_module(module, path) except ImportError: f = None if f is None: fullpath = list(path) + sys.path f, file, (suff, mode, type) = imp.find_module(module, fullpath) if type == imp.PKG_DIRECTORY: dict['__path__'] = [file] _modules[module] = dict path = [file] + path f, file, (suff, mode, type) = \ imp.find_module('__init__', [file]) if type != imp.PY_SOURCE: # not Python source, can't do anything with this module f.close() _modules[module] = dict return dict _modules[module] = dict classstack = [] # stack of (class, indent) pairs g = tokenize.generate_tokens(f.readline) try: for tokentype, token, start, end, line in g: if token == 'def': lineno, thisindent = start tokentype, meth_name, start, end, line = g.next() if tokentype != NAME: continue # Syntax error # close all classes indented at least as much while classstack and \ classstack[-1][1] >= thisindent: del classstack[-1] if classstack: # it's a class method cur_class = classstack[-1][0] cur_class._addmethod(meth_name, lineno) else: # it's a function dict[meth_name] = Function(module, meth_name, file, lineno) elif token == 'class': lineno, thisindent = start tokentype, class_name, start, end, line = g.next() if tokentype != NAME: continue # Syntax error # close all classes indented at least as much while classstack and \ classstack[-1][1] >= thisindent: del classstack[-1] # parse what follows the class name tokentype, token, start, end, line = g.next() inherit = None if token == '(': names = [] # List of superclasses # there's a list of superclasses level = 1 super = [] # Tokens making up current superclass while True: tokentype, token, start, end, line = g.next() if token in (')', ',') and level == 1: n = "".join(super) if n in dict: # we know this super class n = dict[n] else: c = n.split('.') if len(c) > 1: # super class is of the form # module.class: look in module for # class m = c[-2] c = c[-1] if m in _modules: d = _modules[m] if c in d: n = d[c] names.append(n) if token == '(': level += 1 elif token == ')': level -= 1 if level == 0: break elif token == ',' and level == 1: pass else: super.append(token) inherit = names cur_class = Class(module, class_name, inherit, file, lineno) dict[class_name] = cur_class classstack.append((cur_class, thisindent)) elif token == 'import' and start[1] == 0: modules = _getnamelist(g) for mod, mod2 in modules: readmodule_ex(mod, path, inpackage) elif token == 'from' and start[1] == 0: mod, token = _getname(g) if not mod or token != "import": continue names = _getnamelist(g) try: # recursively read the imported module d = readmodule_ex(mod, path, inpackage) except: continue # add any classes that were defined in the imported module # to our name space if they were mentioned in the list for n, n2 in names: if n in d: dict[n2 or n] = d[n] elif n == '*': # only add a name if not already there (to mimic # what Python does internally) also don't add # names that start with _ for n in d: if n[0] != '_' and not n in dict: dict[n] = d[n] except StopIteration: pass f.close() return dict def _getnamelist(g): # Helper to get a comma-separated list of dotted names plus 'as' # clauses. Return a list of pairs (name, name2) where name2 is # the 'as' name, or None if there is no 'as' clause. names = [] while True: name, token = _getname(g) if not name: break if token == 'as': name2, token = _getname(g) else: name2 = None names.append((name, name2)) while token != "," and "\n" not in token: tokentype, token, start, end, line = g.next() if token != ",": break return names def _getname(g): # Helper to get a dotted name, return a pair (name, token) where # name is the dotted name, or None if there was no dotted name, # and token is the next input token. parts = [] tokentype, token, start, end, line = g.next() if tokentype != NAME and token != '*': return (None, token) parts.append(token) while True: tokentype, token, start, end, line = g.next() if token != '.': break tokentype, token, start, end, line = g.next() if tokentype != NAME: break parts.append(token) return (".".join(parts), token)