# The MIT License

#

# Copyright (c) 2009-2011 Andreas Stuehrk

# Copyright (c) 2020-2021 Sebastian Ramacher

#

# Permission is hereby granted, free of charge, to any person obtaining a copy

# of this software and associated documentation files (the "Software"), to deal

# in the Software without restriction, including without limitation the rights

# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

# copies of the Software, and to permit persons to whom the Software is

# furnished to do so, subject to the following conditions:

#

# The above copyright notice and this permission notice shall be included in

# all copies or substantial portions of the Software.

#

# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

# THE SOFTWARE.

import fnmatch

import importlib.machinery

import sys

import warnings

from pathlib import Path

from typing import Optional, Set, Generator, Tuple, Sequence, Iterable, Union

from .line import (

current_word,

current_import,

current_from_import_from,

current_from_import_import,

)

SUFFIXES = importlib.machinery.all_suffixes()

LOADERS = (

(

importlib.machinery.ExtensionFileLoader,

importlib.machinery.EXTENSION_SUFFIXES,

),

(

importlib.machinery.SourceFileLoader,

importlib.machinery.SOURCE_SUFFIXES,

),

)

class ModuleGatherer:

def __init__(

self,

paths: Optional[Iterable[Union[str, Path]]] = None,

skiplist: Optional[Sequence[str]] = None,

) -> None:

"""Initialize module gatherer with all modules in `paths`, which should be a list of

directory names. If `paths` is not given, `sys.path` will be used."""

# Cached list of all known modules

self.modules: Set[str] = set()

# Set of (st_dev, st_ino) to compare against so that paths are not repeated

self.paths: Set[Tuple[int, int]] = set()

# Patterns to skip

self.skiplist: Sequence[str] = (

skiplist if skiplist is not None else tuple()

)

self.fully_loaded = False

if paths is None:

self.modules.update(sys.builtin_module_names)

paths = sys.path

self.find_iterator = self.find_all_modules(

(Path(p).resolve() if p else Path.cwd() for p in paths)

)

def module_matches(self, cw: str, prefix: str = "") -> Set[str]:

"""Modules names to replace cw with"""

full = f"{prefix}.{cw}" if prefix else cw

matches = (

name

for name in self.modules

if (name.startswith(full) and name.find(".", len(full)) == -1)

)

if prefix:

return {match[len(prefix) + 1 :] for match in matches}

else:

return set(matches)

def attr_matches(

self, cw: str, prefix: str = "", only_modules: bool = False

) -> Set[str]:

"""Attributes to replace name with"""

full = f"{prefix}.{cw}" if prefix else cw

module_name, _, name_after_dot = full.rpartition(".")

if module_name not in sys.modules:

return set()

module = sys.modules[module_name]

if only_modules:

matches = {

name

for name in dir(module)

if name.startswith(name_after_dot)

and f"{module_name}.{name}" in sys.modules

}

else:

matches = {

name for name in dir(module) if name.startswith(name_after_dot)

}

module_part, _, _ = cw.rpartition(".")

if module_part:

matches = {f"{module_part}.{m}" for m in matches}

return matches

def module_attr_matches(self, name: str) -> Set[str]:

"""Only attributes which are modules to replace name with"""

return self.attr_matches(name, only_modules=True)

def complete(self, cursor_offset: int, line: str) -> Optional[Set[str]]:

"""Construct a full list of possibly completions for imports."""

tokens = line.split()

if "from" not in tokens and "import" not in tokens:

return None

result = current_word(cursor_offset, line)

if result is None:

return None

from_import_from = current_from_import_from(cursor_offset, line)

if from_import_from is not None:

import_import = current_from_import_import(cursor_offset, line)

if import_import is not None:

# `from a import <b|>` completion

matches = self.module_matches(

import_import[2], from_import_from[2]

)

matches.update(

self.attr_matches(import_import[2], from_import_from[2])

)

else:

# `from <a|>` completion

matches = self.module_attr_matches(from_import_from[2])

matches.update(self.module_matches(from_import_from[2]))

return matches

cur_import = current_import(cursor_offset, line)

if cur_import is not None:

# `import <a|>` completion

matches = self.module_matches(cur_import[2])

matches.update(self.module_attr_matches(cur_import[2]))

return matches

else:

return None

def find_modules(self, path: Path) -> Generator[str, None, None]:

"""Find all modules (and packages) for a given directory."""

if not path.is_dir():

# Perhaps a zip file

return

if any(fnmatch.fnmatch(path.name, entry) for entry in self.skiplist):

# Path is on skiplist

return

try:

# https://bugs.python.org/issue34541

# Once we migrate to Python 3.8, we can change it back to directly iterator over

# path.iterdir().

children = tuple(path.iterdir())

except OSError:

# Path is not readable

return

finder = importlib.machinery.FileFinder(str(path), *LOADERS) # type: ignore

for p in children:

if any(fnmatch.fnmatch(p.name, entry) for entry in self.skiplist):

# Path is on skiplist

continue

elif not any(p.name.endswith(suffix) for suffix in SUFFIXES):

# Possibly a package

if "." in p.name:

continue

elif p.is_dir():

# Unfortunately, CPython just crashes if there is a directory

# which ends with a python extension, so work around.

continue

name = p.name

for suffix in SUFFIXES:

if name.endswith(suffix):

name = name[: -len(suffix)]

break

if name == "badsyntax_pep3120":

# Workaround for issue #166

continue

try:

is_package = False

with warnings.catch_warnings():

warnings.simplefilter("ignore", ImportWarning)

spec = finder.find_spec(name)

if spec is None:

continue

if spec.submodule_search_locations is not None:

pathname = spec.submodule_search_locations[0]

is_package = True

except (ImportError, OSError, SyntaxError):

continue

except UnicodeEncodeError:

# Happens with Python 3 when there is a filename in some invalid encoding

continue

else:

if is_package:

path_real = Path(pathname).resolve()

try:

stat = path_real.stat()

except OSError:

continue

if (stat.st_dev, stat.st_ino) not in self.paths:

self.paths.add((stat.st_dev, stat.st_ino))

for subname in self.find_modules(path_real):

if subname != "__init__":

yield f"{name}.{subname}"

yield name

def find_all_modules(

self, paths: Iterable[Path]

) -> Generator[None, None, None]:

"""Return a list with all modules in `path`, which should be a list of

directory names. If path is not given, sys.path will be used."""

for p in paths:

for module in self.find_modules(p):

self.modules.add(module)

yield

def find_coroutine(self) -> Optional[bool]:

if self.fully_loaded:

return None

try:

next(self.find_iterator)

except StopIteration:

self.fully_loaded = True

return True