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Editing: modulefinder.py
"""Find modules used by a script, using introspection.""" import dis import importlib._bootstrap_external import importlib.machinery import marshal import os import io import sys # Old imp constants: _SEARCH_ERROR = 0 _PY_SOURCE = 1 _PY_COMPILED = 2 _C_EXTENSION = 3 _PKG_DIRECTORY = 5 _C_BUILTIN = 6 _PY_FROZEN = 7 # Modulefinder does a good job at simulating Python's, but it can not # handle __path__ modifications packages make at runtime. Therefore there # is a mechanism whereby you can register extra paths in this map for a # package, and it will be honored. # Note this is a mapping is lists of paths. packagePathMap = {} # A Public interface def AddPackagePath(packagename, path): packagePathMap.setdefault(packagename, []).append(path) replacePackageMap = {} # This ReplacePackage mechanism allows modulefinder to work around # situations in which a package injects itself under the name # of another package into sys.modules at runtime by calling # ReplacePackage("real_package_name", "faked_package_name") # before running ModuleFinder. def ReplacePackage(oldname, newname): replacePackageMap[oldname] = newname def _find_module(name, path=None): """An importlib reimplementation of imp.find_module (for our purposes).""" # It's necessary to clear the caches for our Finder first, in case any # modules are being added/deleted/modified at runtime. In particular, # test_modulefinder.py changes file tree contents in a cache-breaking way: importlib.machinery.PathFinder.invalidate_caches() spec = importlib.machinery.PathFinder.find_spec(name, path) if spec is None: raise ImportError("No module named {name!r}".format(name=name), name=name) # Some special cases: if spec.loader is importlib.machinery.BuiltinImporter: return None, None, ("", "", _C_BUILTIN) if spec.loader is importlib.machinery.FrozenImporter: return None, None, ("", "", _PY_FROZEN) file_path = spec.origin if spec.loader.is_package(name): return None, os.path.dirname(file_path), ("", "", _PKG_DIRECTORY) if isinstance(spec.loader, importlib.machinery.SourceFileLoader): kind = _PY_SOURCE elif isinstance(spec.loader, importlib.machinery.ExtensionFileLoader): kind = _C_EXTENSION elif isinstance(spec.loader, importlib.machinery.SourcelessFileLoader): kind = _PY_COMPILED else: # Should never happen. return None, None, ("", "", _SEARCH_ERROR) file = io.open_code(file_path) suffix = os.path.splitext(file_path)[-1] return file, file_path, (suffix, "rb", kind) class Module: def __init__(self, name, file=None, path=None): self.__name__ = name self.__file__ = file self.__path__ = path self.__code__ = None # The set of global names that are assigned to in the module. # This includes those names imported through starimports of # Python modules. self.globalnames = {} # The set of starimports this module did that could not be # resolved, ie. a starimport from a non-Python module. self.starimports = {} def __repr__(self): s = "Module(%r" % (self.__name__,) if self.__file__ is not None: s = s + ", %r" % (self.__file__,) if self.__path__ is not None: s = s + ", %r" % (self.__path__,) s = s + ")" return s class ModuleFinder: def __init__(self, path=None, debug=0, excludes=None, replace_paths=None): if path is None: path = sys.path self.path = path self.modules = {} self.badmodules = {} self.debug = debug self.indent = 0 self.excludes = excludes if excludes is not None else [] self.replace_paths = replace_paths if replace_paths is not None else [] self.processed_paths = [] # Used in debugging only def msg(self, level, str, *args): if level <= self.debug: for i in range(self.indent): print(" ", end=' ') print(str, end=' ') for arg in args: print(repr(arg), end=' ') print() def msgin(self, *args): level = args[0] if level <= self.debug: self.indent = self.indent + 1 self.msg(*args) def msgout(self, *args): level = args[0] if level <= self.debug: self.indent = self.indent - 1 self.msg(*args) def run_script(self, pathname): self.msg(2, "run_script", pathname) with io.open_code(pathname) as fp: stuff = ("", "rb", _PY_SOURCE) self.load_module('__main__', fp, pathname, stuff) def load_file(self, pathname): dir, name = os.path.split(pathname) name, ext = os.path.splitext(name) with io.open_code(pathname) as fp: stuff = (ext, "rb", _PY_SOURCE) self.load_module(name, fp, pathname, stuff) def import_hook(self, name, caller=None, fromlist=None, level=-1): self.msg(3, "import_hook", name, caller, fromlist, level) parent = self.determine_parent(caller, level=level) q, tail = self.find_head_package(parent, name) m = self.load_tail(q, tail) if not fromlist: return q if m.__path__: self.ensure_fromlist(m, fromlist) return None def determine_parent(self, caller, level=-1): self.msgin(4, "determine_parent", caller, level) if not caller or level == 0: self.msgout(4, "determine_parent -> None") return None pname = caller.__name__ if level >= 1: # relative import if caller.__path__: level -= 1 if level == 0: parent = self.modules[pname] assert parent is caller self.msgout(4, "determine_parent ->", parent) return parent if pname.count(".") < level: raise ImportError("relative importpath too deep") pname = ".".join(pname.split(".")[:-level]) parent = self.modules[pname] self.msgout(4, "determine_parent ->", parent) return parent if caller.__path__: parent = self.modules[pname] assert caller is parent self.msgout(4, "determine_parent ->", parent) return parent if '.' in pname: i = pname.rfind('.') pname = pname[:i] parent = self.modules[pname] assert parent.__name__ == pname self.msgout(4, "determine_parent ->", parent) return parent self.msgout(4, "determine_parent -> None") return None def find_head_package(self, parent, name): self.msgin(4, "find_head_package", parent, name) if '.' in name: i = name.find('.') head = name[:i] tail = name[i+1:] else: head = name tail = "" if parent: qname = "%s.%s" % (parent.__name__, head) else: qname = head q = self.import_module(head, qname, parent) if q: self.msgout(4, "find_head_package ->", (q, tail)) return q, tail if parent: qname = head parent = None q = self.import_module(head, qname, parent) if q: self.msgout(4, "find_head_package ->", (q, tail)) return q, tail self.msgout(4, "raise ImportError: No module named", qname) raise ImportError("No module named " + qname) def load_tail(self, q, tail): self.msgin(4, "load_tail", q, tail) m = q while tail: i = tail.find('.') if i < 0: i = len(tail) head, tail = tail[:i], tail[i+1:] mname = "%s.%s" % (m.__name__, head) m = self.import_module(head, mname, m) if not m: self.msgout(4, "raise ImportError: No module named", mname) raise ImportError("No module named " + mname) self.msgout(4, "load_tail ->", m) return m def ensure_fromlist(self, m, fromlist, recursive=0): self.msg(4, "ensure_fromlist", m, fromlist, recursive) for sub in fromlist: if sub == "*": if not recursive: all = self.find_all_submodules(m) if all: self.ensure_fromlist(m, all, 1) elif not hasattr(m, sub): subname = "%s.%s" % (m.__name__, sub) submod = self.import_module(sub, subname, m) if not submod: raise ImportError("No module named " + subname) def find_all_submodules(self, m): if not m.__path__: return modules = {} # 'suffixes' used to be a list hardcoded to [".py", ".pyc"]. # But we must also collect Python extension modules - although # we cannot separate normal dlls from Python extensions. suffixes = [] suffixes += importlib.machinery.EXTENSION_SUFFIXES[:] suffixes += importlib.machinery.SOURCE_SUFFIXES[:] suffixes += importlib.machinery.BYTECODE_SUFFIXES[:] for dir in m.__path__: try: names = os.listdir(dir) except OSError: self.msg(2, "can't list directory", dir) continue for name in names: mod = None for suff in suffixes: n = len(suff) if name[-n:] == suff: mod = name[:-n] break if mod and mod != "__init__": modules[mod] = mod return modules.keys() def import_module(self, partname, fqname, parent): self.msgin(3, "import_module", partname, fqname, parent) try: m = self.modules[fqname] except KeyError: pass else: self.msgout(3, "import_module ->", m) return m if fqname in self.badmodules: self.msgout(3, "import_module -> None") return None if parent and parent.__path__ is None: self.msgout(3, "import_module -> None") return None try: fp, pathname, stuff = self.find_module(partname, parent and parent.__path__, parent) except ImportError: self.msgout(3, "import_module ->", None) return None try: m = self.load_module(fqname, fp, pathname, stuff) finally: if fp: fp.close() if parent: setattr(parent, partname, m) self.msgout(3, "import_module ->", m) return m def load_module(self, fqname, fp, pathname, file_info): suffix, mode, type = file_info self.msgin(2, "load_module", fqname, fp and "fp", pathname) if type == _PKG_DIRECTORY: m = self.load_package(fqname, pathname) self.msgout(2, "load_module ->", m) return m if type == _PY_SOURCE: co = compile(fp.read(), pathname, 'exec') elif type == _PY_COMPILED: try: data = fp.read() importlib._bootstrap_external._classify_pyc(data, fqname, {}) except ImportError as exc: self.msgout(2, "raise ImportError: " + str(exc), pathname) raise co = marshal.loads(memoryview(data)[16:]) else: co = None m = self.add_module(fqname) m.__file__ = pathname if co: if self.replace_paths: co = self.replace_paths_in_code(co) m.__code__ = co self.scan_code(co, m) self.msgout(2, "load_module ->", m) return m def _add_badmodule(self, name, caller): if name not in self.badmodules: self.badmodules[name] = {} if caller: self.badmodules[name][caller.__name__] = 1 else: self.badmodules[name]["-"] = 1 def _safe_import_hook(self, name, caller, fromlist, level=-1): # wrapper for self.import_hook() that won't raise ImportError if name in self.badmodules: self._add_badmodule(name, caller) return try: self.import_hook(name, caller, level=level) except ImportError as msg: self.msg(2, "ImportError:", str(msg)) self._add_badmodule(name, caller) except SyntaxError as msg: self.msg(2, "SyntaxError:", str(msg)) self._add_badmodule(name, caller) else: if fromlist: for sub in fromlist: fullname = name + "." + sub if fullname in self.badmodules: self._add_badmodule(fullname, caller) continue try: self.import_hook(name, caller, [sub], level=level) except ImportError as msg: self.msg(2, "ImportError:", str(msg)) self._add_badmodule(fullname, caller) def scan_opcodes(self, co): # Scan the code, and yield 'interesting' opcode combinations for name in dis._find_store_names(co): yield "store", (name,) for name, level, fromlist in dis._find_imports(co): if level == 0: # absolute import yield "absolute_import", (fromlist, name) else: # relative import yield "relative_import", (level, fromlist, name) def scan_code(self, co, m): code = co.co_code scanner = self.scan_opcodes for what, args in scanner(co): if what == "store": name, = args m.globalnames[name] = 1 elif what == "absolute_import": fromlist, name = args have_star = 0 if fromlist is not None: if "*" in fromlist: have_star = 1 fromlist = [f for f in fromlist if f != "*"] self._safe_import_hook(name, m, fromlist, level=0) if have_star: # We've encountered an "import *". If it is a Python module, # the code has already been parsed and we can suck out the # global names. mm = None if m.__path__: # At this point we don't know whether 'name' is a # submodule of 'm' or a global module. Let's just try # the full name first. mm = self.modules.get(m.__name__ + "." + name) if mm is None: mm = self.modules.get(name) if mm is not None: m.globalnames.update(mm.globalnames) m.starimports.update(mm.starimports) if mm.__code__ is None: m.starimports[name] = 1 else: m.starimports[name] = 1 elif what == "relative_import": level, fromlist, name = args if name: self._safe_import_hook(name, m, fromlist, level=level) else: parent = self.determine_parent(m, level=level) self._safe_import_hook(parent.__name__, None, fromlist, level=0) else: # We don't expect anything else from the generator. raise RuntimeError(what) for c in co.co_consts: if isinstance(c, type(co)): self.scan_code(c, m) def load_package(self, fqname, pathname): self.msgin(2, "load_package", fqname, pathname) newname = replacePackageMap.get(fqname) if newname: fqname = newname m = self.add_module(fqname) m.__file__ = pathname m.__path__ = [pathname] # As per comment at top of file, simulate runtime __path__ additions. m.__path__ = m.__path__ + packagePathMap.get(fqname, []) fp, buf, stuff = self.find_module("__init__", m.__path__) try: self.load_module(fqname, fp, buf, stuff) self.msgout(2, "load_package ->", m) return m finally: if fp: fp.close() def add_module(self, fqname): if fqname in self.modules: return self.modules[fqname] self.modules[fqname] = m = Module(fqname) return m def find_module(self, name, path, parent=None): if parent is not None: # assert path is not None fullname = parent.__name__+'.'+name else: fullname = name if fullname in self.excludes: self.msgout(3, "find_module -> Excluded", fullname) raise ImportError(name) if path is None: if name in sys.builtin_module_names: return (None, None, ("", "", _C_BUILTIN)) path = self.path return _find_module(name, path) def report(self): """Print a report to stdout, listing the found modules with their paths, as well as modules that are missing, or seem to be missing. """ print() print(" %-25s %s" % ("Name", "File")) print(" %-25s %s" % ("----", "----")) # Print modules found keys = sorted(self.modules.keys()) for key in keys: m = self.modules[key] if m.__path__: print("P", end=' ') else: print("m", end=' ') print("%-25s" % key, m.__file__ or "") # Print missing modules missing, maybe = self.any_missing_maybe() if missing: print() print("Missing modules:") for name in missing: mods = sorted(self.badmodules[name].keys()) print("?", name, "imported from", ', '.join(mods)) # Print modules that may be missing, but then again, maybe not... if maybe: print() print("Submodules that appear to be missing, but could also be", end=' ') print("global names in the parent package:") for name in maybe: mods = sorted(self.badmodules[name].keys()) print("?", name, "imported from", ', '.join(mods)) def any_missing(self): """Return a list of modules that appear to be missing. Use any_missing_maybe() if you want to know which modules are certain to be missing, and which *may* be missing. """ missing, maybe = self.any_missing_maybe() return missing + maybe def any_missing_maybe(self): """Return two lists, one with modules that are certainly missing and one with modules that *may* be missing. The latter names could either be submodules *or* just global names in the package. The reason it can't always be determined is that it's impossible to tell which names are imported when "from module import *" is done with an extension module, short of actually importing it. """ missing = [] maybe = [] for name in self.badmodules: if name in self.excludes: continue i = name.rfind(".") if i < 0: missing.append(name) continue subname = name[i+1:] pkgname = name[:i] pkg = self.modules.get(pkgname) if pkg is not None: if pkgname in self.badmodules[name]: # The package tried to import this module itself and # failed. It's definitely missing. missing.append(name) elif subname in pkg.globalnames: # It's a global in the package: definitely not missing. pass elif pkg.starimports: # It could be missing, but the package did an "import *" # from a non-Python module, so we simply can't be sure. maybe.append(name) else: # It's not a global in the package, the package didn't # do funny star imports, it's very likely to be missing. # The symbol could be inserted into the package from the # outside, but since that's not good style we simply list # it missing. missing.append(name) else: missing.append(name) missing.sort() maybe.sort() return missing, maybe def replace_paths_in_code(self, co): new_filename = original_filename = os.path.normpath(co.co_filename) for f, r in self.replace_paths: if original_filename.startswith(f): new_filename = r + original_filename[len(f):] break if self.debug and original_filename not in self.processed_paths: if new_filename != original_filename: self.msgout(2, "co_filename %r changed to %r" \ % (original_filename,new_filename,)) else: self.msgout(2, "co_filename %r remains unchanged" \ % (original_filename,)) self.processed_paths.append(original_filename) consts = list(co.co_consts) for i in range(len(consts)): if isinstance(consts[i], type(co)): consts[i] = self.replace_paths_in_code(consts[i]) return co.replace(co_consts=tuple(consts), co_filename=new_filename) def test(): # Parse command line import getopt try: opts, args = getopt.getopt(sys.argv[1:], "dmp:qx:") except getopt.error as msg: print(msg) return # Process options debug = 1 domods = 0 addpath = [] exclude = [] for o, a in opts: if o == '-d': debug = debug + 1 if o == '-m': domods = 1 if o == '-p': addpath = addpath + a.split(os.pathsep) if o == '-q': debug = 0 if o == '-x': exclude.append(a) # Provide default arguments if not args: script = "hello.py" else: script = args[0] # Set the path based on sys.path and the script directory path = sys.path[:] path[0] = os.path.dirname(script) path = addpath + path if debug > 1: print("path:") for item in path: print(" ", repr(item)) # Create the module finder and turn its crank mf = ModuleFinder(path, debug, exclude) for arg in args[1:]: if arg == '-m': domods = 1 continue if domods: if arg[-2:] == '.*': mf.import_hook(arg[:-2], None, ["*"]) else: mf.import_hook(arg) else: mf.load_file(arg) mf.run_script(script) mf.report() return mf # for -i debugging if __name__ == '__main__': try: mf = test() except KeyboardInterrupt: print("\n[interrupted]")
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