Remove trailing slash from URL in Zip extraction

If the URL ends with a trailing slash, the code that searches for the
expected ZIP subdirectory calculates it incorrectly, so simply strip any
trailing slash if it's present.

Author: chennes

AddonManagerTest/app/test_installer.py

@@ -166,19 +166,28 @@ def test_code_in_branch_subdirectory_more_than_one(self):
 
     def test_move_code_out_of_subdirectory(self):
         """All files are moved out and the subdirectory is deleted"""
-        self.mock_addon.url = "https://something.com/something_else/something"
-        installer = AddonInstaller(self.mock_addon, [])
-        with tempfile.TemporaryDirectory() as temp_dir:
-            subdir = os.path.join(temp_dir, f"something-{self.mock_addon.branch}")
-            os.mkdir(subdir)
-            with open(os.path.join(subdir, "README.txt"), "w", encoding="utf-8") as f:
-                f.write("# Test file for unit testing")
-            with open(os.path.join(subdir, "AnotherFile.txt"), "w", encoding="utf-8") as f:
-                f.write("# Test file for unit testing")
-            installer._move_code_out_of_subdirectory(temp_dir)
-            self.assertTrue(os.path.isfile(os.path.join(temp_dir, "README.txt")))
-            self.assertTrue(os.path.isfile(os.path.join(temp_dir, "AnotherFile.txt")))
-            self.assertFalse(os.path.isdir(subdir))
+        test_urls = [
+            "https://something.com/something_else/something",
+            "https://something.com/something_else/something.git",
+            "https://something.com/something_else/something/",
+            "https://something.com/something_else/something.git/",
+        ]
+        for url in test_urls:
+            with self.subTest(url=url):
+                self.mock_addon.url = url
+                installer = AddonInstaller(self.mock_addon, [])
+                # TODO: Someday use a mock filesystem instead of a temp dir
+                with tempfile.TemporaryDirectory() as temp_dir:
+                    subdir = os.path.join(temp_dir, f"something-{self.mock_addon.branch}")
+                    os.mkdir(subdir)
+                    with open(os.path.join(subdir, "README.txt"), "w", encoding="utf-8") as f:
+                        f.write("# Test file for unit testing")
+                    with open(os.path.join(subdir, "AnotherFile.txt"), "w", encoding="utf-8") as f:
+                        f.write("# Test file for unit testing")
+                    installer._move_code_out_of_subdirectory(temp_dir)
+                    self.assertTrue(os.path.isfile(os.path.join(temp_dir, "README.txt")))
+                    self.assertTrue(os.path.isfile(os.path.join(temp_dir, "AnotherFile.txt")))
+                    self.assertFalse(os.path.isdir(subdir))
 
     def test_install_by_git(self):
         """Test using git to install. Depends on there being a local git

addonmanager_installer.py

@@ -419,6 +419,8 @@ def _code_in_branch_subdirectory(self, destination: str) -> bool:
 
     def _expected_subdirectory_name(self) -> str:
         url = self.addon_to_install.url
+        if url.endswith("/"):
+            url = url[:-1]
         if url.endswith(".git"):
             url = url[:-4]
         _, _, name = url.rpartition("/")