gh-114099 - Add iOS framework loading machinery. (GH-116454)

Co-authored-by: Malcolm Smith <smith@chaquo.com>
Co-authored-by: Eric Snow <ericsnowcurrently@gmail.com>

4 files changed, 74 insertions, 24 deletions

diff --git a/Lib/test/test_importlib/extension/test_finder.py b/Lib/test/test_importlib/extension/test_finder.py
index 3de120958fd..cdc8884d668 100644
--- a/Lib/test/test_importlib/extension/test_finder.py
+++ b/Lib/test/test_importlib/extension/test_finder.py
@@ -1,3 +1,4 @@
+from test.support import is_apple_mobile
 from test.test_importlib import abc, util
 
 machinery = util.import_importlib('importlib.machinery')
@@ -19,9 +20,27 @@ class FinderTests(abc.FinderTests):
             )
 
     def find_spec(self, fullname):
-        importer = self.machinery.FileFinder(util.EXTENSIONS.path,
-                                            (self.machinery.ExtensionFileLoader,
-                                             self.machinery.EXTENSION_SUFFIXES))
+        if is_apple_mobile:
+            # Apple mobile platforms require a specialist loader that uses
+            # .fwork files as placeholders for the true `.so` files.
+            loaders = [
+                (
+                    self.machinery.AppleFrameworkLoader,
+                    [
+                        ext.replace(".so", ".fwork")
+                        for ext in self.machinery.EXTENSION_SUFFIXES
+                    ]
+                )
+            ]
+        else:
+            loaders = [
+                (
+                    self.machinery.ExtensionFileLoader,
+                    self.machinery.EXTENSION_SUFFIXES
+                )
+            ]
+
+        importer = self.machinery.FileFinder(util.EXTENSIONS.path, *loaders)
 
         return importer.find_spec(fullname)
 
diff --git a/Lib/test/test_importlib/extension/test_loader.py b/Lib/test/test_importlib/extension/test_loader.py
index f4879e75847..7607f0e0857 100644
--- a/Lib/test/test_importlib/extension/test_loader.py
+++ b/Lib/test/test_importlib/extension/test_loader.py
@@ -1,3 +1,4 @@
+from test.support import is_apple_mobile
 from test.test_importlib import abc, util
 
 machinery = util.import_importlib('importlib.machinery')
@@ -23,8 +24,15 @@ class LoaderTests:
             raise unittest.SkipTest(
                 f"{util.EXTENSIONS.name} is a builtin module"
             )
-        self.loader = self.machinery.ExtensionFileLoader(util.EXTENSIONS.name,
-                                                         util.EXTENSIONS.file_path)
+
+        # Apple extensions must be distributed as frameworks. This requires
+        # a specialist loader.
+        if is_apple_mobile:
+            self.LoaderClass = self.machinery.AppleFrameworkLoader
+        else:
+            self.LoaderClass = self.machinery.ExtensionFileLoader
+
+        self.loader = self.LoaderClass(util.EXTENSIONS.name, util.EXTENSIONS.file_path)
 
     def load_module(self, fullname):
         with warnings.catch_warnings():
@@ -32,13 +40,11 @@ class LoaderTests:
             return self.loader.load_module(fullname)
 
     def test_equality(self):
-        other = self.machinery.ExtensionFileLoader(util.EXTENSIONS.name,
-                                                   util.EXTENSIONS.file_path)
+        other = self.LoaderClass(util.EXTENSIONS.name, util.EXTENSIONS.file_path)
         self.assertEqual(self.loader, other)
 
     def test_inequality(self):
-        other = self.machinery.ExtensionFileLoader('_' + util.EXTENSIONS.name,
-                                                   util.EXTENSIONS.file_path)
+        other = self.LoaderClass('_' + util.EXTENSIONS.name, util.EXTENSIONS.file_path)
         self.assertNotEqual(self.loader, other)
 
     def test_load_module_API(self):
@@ -58,8 +64,7 @@ class LoaderTests:
                                 ('__package__', '')]:
                 self.assertEqual(getattr(module, attr), value)
             self.assertIn(util.EXTENSIONS.name, sys.modules)
-            self.assertIsInstance(module.__loader__,
-                                  self.machinery.ExtensionFileLoader)
+            self.assertIsInstance(module.__loader__, self.LoaderClass)
 
     # No extension module as __init__ available for testing.
     test_package = None
@@ -86,7 +91,7 @@ class LoaderTests:
         self.assertFalse(self.loader.is_package(util.EXTENSIONS.name))
         for suffix in self.machinery.EXTENSION_SUFFIXES:
             path = os.path.join('some', 'path', 'pkg', '__init__' + suffix)
-            loader = self.machinery.ExtensionFileLoader('pkg', path)
+            loader = self.LoaderClass('pkg', path)
             self.assertTrue(loader.is_package('pkg'))
 
 
@@ -101,6 +106,14 @@ class SinglePhaseExtensionModuleTests(abc.LoaderTests):
     def setUp(self):
         if not self.machinery.EXTENSION_SUFFIXES or not util.EXTENSIONS:
             raise unittest.SkipTest("Requires dynamic loading support.")
+
+        # Apple extensions must be distributed as frameworks. This requires
+        # a specialist loader.
+        if is_apple_mobile:
+            self.LoaderClass = self.machinery.AppleFrameworkLoader
+        else:
+            self.LoaderClass = self.machinery.ExtensionFileLoader
+
         self.name = '_testsinglephase'
         if self.name in sys.builtin_module_names:
             raise unittest.SkipTest(
@@ -109,8 +122,8 @@ class SinglePhaseExtensionModuleTests(abc.LoaderTests):
         finder = self.machinery.FileFinder(None)
         self.spec = importlib.util.find_spec(self.name)
         assert self.spec
-        self.loader = self.machinery.ExtensionFileLoader(
-            self.name, self.spec.origin)
+
+        self.loader = self.LoaderClass(self.name, self.spec.origin)
 
     def load_module(self):
         with warnings.catch_warnings():
@@ -120,7 +133,7 @@ class SinglePhaseExtensionModuleTests(abc.LoaderTests):
     def load_module_by_name(self, fullname):
         # Load a module from the test extension by name.
         origin = self.spec.origin
-        loader = self.machinery.ExtensionFileLoader(fullname, origin)
+        loader = self.LoaderClass(fullname, origin)
         spec = importlib.util.spec_from_loader(fullname, loader)
         module = importlib.util.module_from_spec(spec)
         loader.exec_module(module)
@@ -137,8 +150,7 @@ class SinglePhaseExtensionModuleTests(abc.LoaderTests):
             with self.assertRaises(AttributeError):
                 module.__path__
             self.assertIs(module, sys.modules[self.name])
-            self.assertIsInstance(module.__loader__,
-                                  self.machinery.ExtensionFileLoader)
+            self.assertIsInstance(module.__loader__, self.LoaderClass)
 
     # No extension module as __init__ available for testing.
     test_package = None
@@ -182,6 +194,14 @@ class MultiPhaseExtensionModuleTests(abc.LoaderTests):
     def setUp(self):
         if not self.machinery.EXTENSION_SUFFIXES or not util.EXTENSIONS:
             raise unittest.SkipTest("Requires dynamic loading support.")
+
+        # Apple extensions must be distributed as frameworks. This requires
+        # a specialist loader.
+        if is_apple_mobile:
+            self.LoaderClass = self.machinery.AppleFrameworkLoader
+        else:
+            self.LoaderClass = self.machinery.ExtensionFileLoader
+
         self.name = '_testmultiphase'
         if self.name in sys.builtin_module_names:
             raise unittest.SkipTest(
@@ -190,8 +210,7 @@ class MultiPhaseExtensionModuleTests(abc.LoaderTests):
         finder = self.machinery.FileFinder(None)
         self.spec = importlib.util.find_spec(self.name)
         assert self.spec
-        self.loader = self.machinery.ExtensionFileLoader(
-            self.name, self.spec.origin)
+        self.loader = self.LoaderClass(self.name, self.spec.origin)
 
     def load_module(self):
         # Load the module from the test extension.
@@ -202,7 +221,7 @@ class MultiPhaseExtensionModuleTests(abc.LoaderTests):
     def load_module_by_name(self, fullname):
         # Load a module from the test extension by name.
         origin = self.spec.origin
-        loader = self.machinery.ExtensionFileLoader(fullname, origin)
+        loader = self.LoaderClass(fullname, origin)
         spec = importlib.util.spec_from_loader(fullname, loader)
         module = importlib.util.module_from_spec(spec)
         loader.exec_module(module)
@@ -228,8 +247,7 @@ class MultiPhaseExtensionModuleTests(abc.LoaderTests):
             with self.assertRaises(AttributeError):
                 module.__path__
             self.assertIs(module, sys.modules[self.name])
-            self.assertIsInstance(module.__loader__,
-                                  self.machinery.ExtensionFileLoader)
+            self.assertIsInstance(module.__loader__, self.LoaderClass)
 
     def test_functionality(self):
         # Test basic functionality of stuff defined in an extension module.
diff --git a/Lib/test/test_importlib/test_util.py b/Lib/test/test_importlib/test_util.py
index a09286806e5..a6a76e58976 100644
--- a/Lib/test/test_importlib/test_util.py
+++ b/Lib/test/test_importlib/test_util.py
@@ -707,13 +707,20 @@ class IncompatibleExtensionModuleRestrictionsTests(unittest.TestCase):
 
     @unittest.skipIf(_testmultiphase is None, "test requires _testmultiphase module")
     def test_incomplete_multi_phase_init_module(self):
+        # Apple extensions must be distributed as frameworks. This requires
+        # a specialist loader.
+        if support.is_apple_mobile:
+            loader = "AppleFrameworkLoader"
+        else:
+            loader = "ExtensionFileLoader"
+
         prescript = textwrap.dedent(f'''
             from importlib.util import spec_from_loader, module_from_spec
-            from importlib.machinery import ExtensionFileLoader
+            from importlib.machinery import {loader}
 
             name = '_test_shared_gil_only'
             filename = {_testmultiphase.__file__!r}
-            loader = ExtensionFileLoader(name, filename)
+            loader = {loader}(name, filename)
             spec = spec_from_loader(name, loader)
 
             ''')
diff --git a/Lib/test/test_importlib/util.py b/Lib/test/test_importlib/util.py
index a900cc1dddf..89272484009 100644
--- a/Lib/test/test_importlib/util.py
+++ b/Lib/test/test_importlib/util.py
@@ -8,6 +8,7 @@ import os
 import os.path
 from test import support
 from test.support import import_helper
+from test.support import is_apple_mobile
 from test.support import os_helper
 import unittest
 import sys
@@ -43,6 +44,11 @@ else:
         global EXTENSIONS
         for path in sys.path:
             for ext in machinery.EXTENSION_SUFFIXES:
+                # Apple mobile platforms mechanically load .so files,
+                # but the findable files are labelled .fwork
+                if is_apple_mobile:
+                    ext = ext.replace(".so", ".fwork")
+
                 filename = EXTENSIONS.name + ext
                 file_path = os.path.join(path, filename)
                 if os.path.exists(file_path):