bpo-45514: Deprecate importlib resources legacy functions. (GH-29036)

* bpo-45514: Apply changes from importlib_resources@a3ef4128c6

* Mark legacy functions as deprecated in the docs and link to the migration docs in importlib_resources docs.

* Apply changes from importlib_resources@329ae9d5f2c.

* Indicate importlib.resources as a module.

Co-authored-by: Filipe Laíns <lains@riseup.net>

Doc/library/importlib.rst

@@ -917,7 +917,9 @@ not** have to exist as physical files and directories on the file system.
    on `using importlib.resources
    <http://importlib-resources.readthedocs.io/en/latest/using.html>`_ and
    `migrating from pkg_resources to importlib.resources
-   <http://importlib-resources.readthedocs.io/en/latest/migration.html>`_.
+   <http://importlib-resources.readthedocs.io/en/latest/migration.html>`_
+   and
+   `migrating legacy usage <https://importlib-resources.readthedocs.io/en/latest/using.html#migrating-from-legacy>`_.
 
 Loaders that wish to support resource reading should implement a
 ``get_resource_reader(fullname)`` method as specified by
@@ -979,6 +981,8 @@ The following functions are available.
     sub-resources (i.e. it cannot be a directory).  This function returns a
     ``typing.BinaryIO`` instance, a binary I/O stream open for reading.
 
+   .. deprecated:: 3.11
+
 
 .. function:: open_text(package, resource, encoding='utf-8', errors='strict')
 
@@ -994,6 +998,8 @@ The following functions are available.
     This function returns a ``typing.TextIO`` instance, a text I/O stream open
     for reading.
 
+   .. deprecated:: 3.11
+
 
 .. function:: read_binary(package, resource)
 
@@ -1006,6 +1012,8 @@ The following functions are available.
     sub-resources (i.e. it cannot be a directory).  This function returns the
     contents of the resource as :class:`bytes`.
 
+   .. deprecated:: 3.11
+
 
 .. function:: read_text(package, resource, encoding='utf-8', errors='strict')
 
@@ -1019,6 +1027,8 @@ The following functions are available.
     have the same meaning as with built-in :func:`open`.  This function
     returns the contents of the resource as :class:`str`.
 
+   .. deprecated:: 3.11
+
 
 .. function:: path(package, resource)
 
@@ -1034,6 +1044,8 @@ The following functions are available.
     within *package*; it may not contain path separators and it may not have
     sub-resources (i.e. it cannot be a directory).
 
+   .. deprecated:: 3.11
+
 
 .. function:: is_resource(package, name)
 
@@ -1042,6 +1054,8 @@ The following functions are available.
     *package* is either a name or a module object which conforms to the
     ``Package`` requirements.
 
+   .. deprecated:: 3.11
+
 
 .. function:: contents(package)
 
@@ -1052,6 +1066,8 @@ The following functions are available.
     *package* is either a name or a module object which conforms to the
     ``Package`` requirements.
 
+   .. deprecated:: 3.11
+
 
 :mod:`importlib.machinery` -- Importers and path hooks
 ------------------------------------------------------

Lib/importlib/_itertools.py

@@ -1,11 +1,27 @@
 from itertools import filterfalse
 
+from typing import (
+    Callable,
+    Iterable,
+    Iterator,
+    Optional,
+    Set,
+    TypeVar,
+    Union,
+)
 
-def unique_everseen(iterable, key=None):
+# Type and type variable definitions
+_T = TypeVar('_T')
+_U = TypeVar('_U')
+
+
+def unique_everseen(
+    iterable: Iterable[_T], key: Optional[Callable[[_T], _U]] = None
+) -> Iterator[_T]:
     "List unique elements, preserving order. Remember all elements ever seen."
     # unique_everseen('AAAABBBCCDAABBB') --> A B C D
     # unique_everseen('ABBCcAD', str.lower) --> A B C D
-    seen = set()
+    seen: Set[Union[_T, _U]] = set()
     seen_add = seen.add
     if key is None:
         for element in filterfalse(seen.__contains__, iterable):

Lib/importlib/_legacy.py

@@ -1,6 +1,8 @@
+import functools
 import os
 import pathlib
 import types
+import warnings
 
 from typing import Union, Iterable, ContextManager, BinaryIO, TextIO
 
@@ -10,16 +12,34 @@
 Resource = Union[str, os.PathLike]
 
 
+def deprecated(func):
+    @functools.wraps(func)
+    def wrapper(*args, **kwargs):
+        warnings.warn(
+            f"{func.__name__} is deprecated. Use files() instead. "
+            "Refer to https://importlib-resources.readthedocs.io"
+            "/en/latest/using.html#migrating-from-legacy for migration advice.",
+            DeprecationWarning,
+            stacklevel=2,
+        )
+        return func(*args, **kwargs)
+
+    return wrapper
+
+
+@deprecated
 def open_binary(package: Package, resource: Resource) -> BinaryIO:
     """Return a file-like object opened for binary reading of the resource."""
     return (_common.files(package) / _common.normalize_path(resource)).open('rb')
 
 
+@deprecated
 def read_binary(package: Package, resource: Resource) -> bytes:
     """Return the binary contents of the resource."""
     return (_common.files(package) / _common.normalize_path(resource)).read_bytes()
 
 
+@deprecated
 def open_text(
     package: Package,
     resource: Resource,
@@ -32,6 +52,7 @@ def open_text(
     )
 
 
+@deprecated
 def read_text(
     package: Package,
     resource: Resource,
@@ -47,6 +68,7 @@ def read_text(
         return fp.read()
 
 
+@deprecated
 def contents(package: Package) -> Iterable[str]:
     """Return an iterable of entries in `package`.
 
@@ -57,6 +79,7 @@ def contents(package: Package) -> Iterable[str]:
     return [path.name for path in _common.files(package).iterdir()]
 
 
+@deprecated
 def is_resource(package: Package, name: str) -> bool:
     """True if `name` is a resource inside `package`.
 
@@ -69,6 +92,7 @@ def is_resource(package: Package, name: str) -> bool:
     )
 
 
+@deprecated
 def path(
     package: Package,
     resource: Resource,

Lib/test/test_importlib/resources/util.py

@@ -1,8 +1,10 @@
 import abc
+import contextlib
 import importlib
 import io
 import sys
 import types
+import warnings
 from pathlib import Path, PurePath
 
 from .. import data01
@@ -67,6 +69,13 @@ def create_package(file=None, path=None, is_package=True, contents=()):
     )
 
 
+@contextlib.contextmanager
+def suppress_known_deprecation():
+    with warnings.catch_warnings(record=True) as ctx:
+        warnings.simplefilter('default', category=DeprecationWarning)
+        yield ctx
+
+
 class CommonTests(metaclass=abc.ABCMeta):
     """
     Tests shared by test_open, test_path, and test_read.

Lib/test/test_importlib/test_contents.py

@@ -15,7 +15,8 @@ class ContentsTests:
     }
 
     def test_contents(self):
-        assert self.expected <= set(resources.contents(self.data))
+        with util.suppress_known_deprecation():
+            assert self.expected <= set(resources.contents(self.data))
 
 
 class ContentsDiskTests(ContentsTests, unittest.TestCase):

Lib/test/test_importlib/test_open.py

@@ -7,38 +7,47 @@
 
 class CommonBinaryTests(util.CommonTests, unittest.TestCase):
     def execute(self, package, path):
-        with resources.open_binary(package, path):
-            pass
+        with util.suppress_known_deprecation():
+            with resources.open_binary(package, path):
+                pass
 
 
 class CommonTextTests(util.CommonTests, unittest.TestCase):
     def execute(self, package, path):
-        with resources.open_text(package, path):
-            pass
+        with util.suppress_known_deprecation():
+            with resources.open_text(package, path):
+                pass
 
 
 class OpenTests:
     def test_open_binary(self):
-        with resources.open_binary(self.data, 'binary.file') as fp:
-            result = fp.read()
-            self.assertEqual(result, b'\x00\x01\x02\x03')
+        with util.suppress_known_deprecation():
+            with resources.open_binary(self.data, 'binary.file') as fp:
+                result = fp.read()
+                self.assertEqual(result, b'\x00\x01\x02\x03')
 
     def test_open_text_default_encoding(self):
-        with resources.open_text(self.data, 'utf-8.file') as fp:
-            result = fp.read()
+        with util.suppress_known_deprecation():
+            with resources.open_text(self.data, 'utf-8.file') as fp:
+                result = fp.read()
             self.assertEqual(result, 'Hello, UTF-8 world!\n')
 
     def test_open_text_given_encoding(self):
-        with resources.open_text(self.data, 'utf-16.file', 'utf-16', 'strict') as fp:
-            result = fp.read()
+        with util.suppress_known_deprecation():
+            with resources.open_text(
+                self.data, 'utf-16.file', 'utf-16', 'strict'
+            ) as fp:
+                result = fp.read()
         self.assertEqual(result, 'Hello, UTF-16 world!\n')
 
     def test_open_text_with_errors(self):
         # Raises UnicodeError without the 'errors' argument.
-        with resources.open_text(self.data, 'utf-16.file', 'utf-8', 'strict') as fp:
-            self.assertRaises(UnicodeError, fp.read)
-        with resources.open_text(self.data, 'utf-16.file', 'utf-8', 'ignore') as fp:
-            result = fp.read()
+        with util.suppress_known_deprecation():
+            with resources.open_text(self.data, 'utf-16.file', 'utf-8', 'strict') as fp:
+                self.assertRaises(UnicodeError, fp.read)
+        with util.suppress_known_deprecation():
+            with resources.open_text(self.data, 'utf-16.file', 'utf-8', 'ignore') as fp:
+                result = fp.read()
         self.assertEqual(
             result,
             'H\x00e\x00l\x00l\x00o\x00,\x00 '
@@ -47,14 +56,16 @@ def test_open_text_with_errors(self):
         )
 
     def test_open_binary_FileNotFoundError(self):
-        self.assertRaises(
-            FileNotFoundError, resources.open_binary, self.data, 'does-not-exist'
-        )
+        with util.suppress_known_deprecation():
+            self.assertRaises(
+                FileNotFoundError, resources.open_binary, self.data, 'does-not-exist'
+            )
 
     def test_open_text_FileNotFoundError(self):
-        self.assertRaises(
-            FileNotFoundError, resources.open_text, self.data, 'does-not-exist'
-        )
+        with util.suppress_known_deprecation():
+            self.assertRaises(
+                FileNotFoundError, resources.open_text, self.data, 'does-not-exist'
+            )
 
 
 class OpenDiskTests(OpenTests, unittest.TestCase):

Lib/test/test_importlib/test_path.py

@@ -8,21 +8,23 @@
 
 class CommonTests(util.CommonTests, unittest.TestCase):
     def execute(self, package, path):
-        with resources.path(package, path):
-            pass
+        with util.suppress_known_deprecation():
+            with resources.path(package, path):
+                pass
 
 
 class PathTests:
     def test_reading(self):
         # Path should be readable.
         # Test also implicitly verifies the returned object is a pathlib.Path
         # instance.
-        with resources.path(self.data, 'utf-8.file') as path:
-            self.assertTrue(path.name.endswith("utf-8.file"), repr(path))
-            # pathlib.Path.read_text() was introduced in Python 3.5.
-            with path.open('r', encoding='utf-8') as file:
-                text = file.read()
-            self.assertEqual('Hello, UTF-8 world!\n', text)
+        with util.suppress_known_deprecation():
+            with resources.path(self.data, 'utf-8.file') as path:
+                self.assertTrue(path.name.endswith("utf-8.file"), repr(path))
+                # pathlib.Path.read_text() was introduced in Python 3.5.
+                with path.open('r', encoding='utf-8') as file:
+                    text = file.read()
+                self.assertEqual('Hello, UTF-8 world!\n', text)
 
 
 class PathDiskTests(PathTests, unittest.TestCase):
@@ -32,8 +34,9 @@ def test_natural_path(self):
         # Guarantee the internal implementation detail that
         # file-system-backed resources do not get the tempdir
         # treatment.
-        with resources.path(self.data, 'utf-8.file') as path:
-            assert 'data' in str(path)
+        with util.suppress_known_deprecation():
+            with resources.path(self.data, 'utf-8.file') as path:
+                assert 'data' in str(path)
 
 
 class PathMemoryTests(PathTests, unittest.TestCase):
@@ -51,8 +54,9 @@ class PathZipTests(PathTests, util.ZipSetup, unittest.TestCase):
     def test_remove_in_context_manager(self):
         # It is not an error if the file that was temporarily stashed on the
         # file system is removed inside the `with` stanza.
-        with resources.path(self.data, 'utf-8.file') as path:
-            path.unlink()
+        with util.suppress_known_deprecation():
+            with resources.path(self.data, 'utf-8.file') as path:
+                path.unlink()
 
 
 if __name__ == '__main__':