gh-105922: Add PyImport_AddModuleRef() function (#105923)

* Add tests on PyImport_AddModuleRef(), PyImport_AddModule() and
  PyImport_AddModuleObject().
* pythonrun.c: Replace Py_XNewRef(PyImport_AddModule(name)) with
  PyImport_AddModuleRef(name).

1 files changed, 24 insertions, 0 deletions

diff --git a/Lib/test/test_import/__init__.py b/Lib/test/test_import/__init__.py
index 71a50bc..f2726da 100644
--- a/Lib/test/test_import/__init__.py
+++ b/Lib/test/test_import/__init__.py
@@ -2621,6 +2621,30 @@ class SinglephaseInitTests(unittest.TestCase):
         #  * module's global state was initialized, not reset
 
 
+@cpython_only
+class CAPITests(unittest.TestCase):
+    def test_pyimport_addmodule(self):
+        # gh-105922: Test PyImport_AddModuleRef(), PyImport_AddModule()
+        # and PyImport_AddModuleObject()
+        import _testcapi
+        for name in (
+            'sys',     # frozen module
+            'test',    # package
+            __name__,  # package.module
+        ):
+            _testcapi.check_pyimport_addmodule(name)
+
+    def test_pyimport_addmodule_create(self):
+        # gh-105922: Test PyImport_AddModuleRef(), create a new module
+        import _testcapi
+        name = 'dontexist'
+        self.assertNotIn(name, sys.modules)
+        self.addCleanup(unload, name)
+
+        mod = _testcapi.check_pyimport_addmodule(name)
+        self.assertIs(mod, sys.modules[name])
+
+
 if __name__ == '__main__':
     # Test needs to be a package, so we can do relative imports.
     unittest.main()