"""Parse a Python module and describe its classes and methods. Parse enough of a Python file to recognize imports and class and method definitions, and to find out the superclasses of a class. The interface consists of a single function: readmodule_ex(module [, path]) where module is the name of a Python module, and 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. 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. One special key/value pair is present for packages: the key '__path__' has a list as its value which contains the package search path. A class is described by the class Class in this module. Instances of this class have the following instance variables: module -- the module name 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. A function is described by the class Function in this module. Instances of this class have the following instance variables: module -- the module name name -- the name of the class file -- the file in which the class was defined lineno -- the line in the file on which the class statement occurred """ import io import sys import importlib.util import tokenize from token import NAME, DEDENT, OP __all__ = ["readmodule", "readmodule_ex", "Class", "Function"] _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 to represent a top-level Python function''' def __init__(self, module, name, file, lineno): self.module = module self.name = name self.file = file self.lineno = lineno def readmodule(module, path=None): '''Backwards compatible interface. Call readmodule_ex() and then only keep Class objects from the resulting dictionary.''' res = {} for key, value in _readmodule(module, path or []).items(): if isinstance(value, Class): res[key] = value return res def readmodule_ex(module, path=None): '''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. ''' return _readmodule(module, path or []) def _readmodule(module, path, inpackage=None): '''Do the hard work for readmodule[_ex]. If INPACKAGE is given, it must be the dotted name of the package in which we are searching for a submodule, and then PATH must be the package search path; otherwise, we are searching for a top-level module, and PATH is combined with sys.path. ''' # Compute the full module name (prepending inpackage if set) if inpackage is not None: fullmodule = "%s.%s" % (inpackage, module) else: fullmodule = module # Check in the cache if fullmodule in _modules: return _modules[fullmodule] # Initialize the dict for this module's contents dict = {} # Check if it is a built-in module; we don't do much for these if module in sys.builtin_module_names and inpackage is None: _modules[module] = dict return dict # Check for a dotted module name i = module.rfind('.') if i >= 0: package = module[:i] submodule = module[i+1:] parent = _readmodule(package, path, inpackage) if inpackage is not None: package = "%s.%s" % (inpackage, package) if not '__path__' in parent: raise ImportError('No package named {}'.format(package)) return _readmodule(submodule, parent['__path__'], package) # Search the path for the module f = None if inpackage is not None: search_path = path else: search_path = path + sys.path # XXX This will change once issue19944 lands. spec = importlib.util._find_spec_from_path(fullmodule, search_path) _modules[fullmodule] = dict # is module a package? if spec.submodule_search_locations is not None: dict['__path__'] = spec.submodule_search_locations try: source = spec.loader.get_source(fullmodule) if source is None: return dict except (AttributeError, ImportError): # not Python source, can't do anything with this module return dict fname = spec.loader.get_filename(fullmodule) f = io.StringIO(source) stack = [] # stack of (class, indent) pairs g = tokenize.generate_tokens(f.readline) try: for tokentype, token, start, _end, _line in g: if tokentype == DEDENT: lineno, thisindent = start # close nested classes and defs while stack and stack[-1][1] >= thisindent: del stack[-1] elif token == 'def': lineno, thisindent = start # close previous nested classes and defs while stack and stack[-1][1] >= thisindent: del stack[-1] tokentype, meth_name, start = next(g)[0:3] if tokentype != NAME: continue # Syntax error if stack: cur_class = stack[-1][0] if isinstance(cur_class, Class): # it's a method cur_class._addmethod(meth_name, lineno) # else it's a nested def else: # it's a function dict[meth_name] = Function(fullmodule, meth_name, fname, lineno) stack.append((None, thisindent)) # Marker for nested fns elif token == 'class': lineno, thisindent = start # close previous nested classes and defs while stack and stack[-1][1] >= thisindent: del stack[-1] tokentype, class_name, start = next(g)[0:3] if tokentype != NAME: continue # Syntax error # parse what follows the class name tokentype, token, start = next(g)[0:3] 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 = next(g)[0:3] 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) super = [] if token == '(': level += 1 elif token == ')': level -= 1 if level == 0: break elif token == ',' and level == 1: pass # only use NAME and OP (== dot) tokens for type name elif tokentype in (NAME, OP) and level == 1: super.append(token) # expressions in the base list are not supported inherit = names cur_class = Class(fullmodule, class_name, inherit, fname, lineno) if not stack: dict[class_name] = cur_class stack.append((cur_class, thisindent)) elif token == 'import' and start[1] == 0: modules = _getnamelist(g) for mod, _mod2 in modules: try: # Recursively read the imported module if inpackage is None: _readmodule(mod, path) else: try: _readmodule(mod, path, inpackage) except ImportError: _readmodule(mod, []) except: # If we can't find or parse the imported module, # too bad -- don't die here. pass 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(mod, path, inpackage) except: # If we can't find or parse the imported module, # too bad -- don't die here. 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 == '*': # don't add names that start with _ for n in d: if n[0] != '_': 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: token = next(g)[1] 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 = next(g)[0:2] if tokentype != NAME and token != '*': return (None, token) parts.append(token) while True: tokentype, token = next(g)[0:2] if token != '.': break tokentype, token = next(g)[0:2] if tokentype != NAME: break parts.append(token) return (".".join(parts), token) def _main(): # Main program for testing. import os from operator import itemgetter mod = sys.argv[1] if os.path.exists(mod): path = [os.path.dirname(mod)] mod = os.path.basename(mod) if mod.lower().endswith(".py"): mod = mod[:-3] else: path = [] dict = readmodule_ex(mod, path) objs = list(dict.values()) objs.sort(key=lambda a: getattr(a, 'lineno', 0)) for obj in objs: if isinstance(obj, Class): print("class", obj.name, obj.super, obj.lineno) methods = sorted(obj.methods.items(), key=itemgetter(1)) for name, lineno in methods: if name != "__path__": print(" def", name, lineno) elif isinstance(obj, Function): print("def", obj.name, obj.lineno) if __name__ == "__main__": _main()