Merge fix for UTF-16 bom handling in tests.

Closes #312. Closes #313. Ref python/cpython#117569

importlib_resources/tests/test_functional.py

@@ -48,6 +48,12 @@ def _gen_resourcetxt_path_parts(self):
             with self.subTest(path_parts=path_parts):
                 yield path_parts
 
+    def assertEndsWith(self, string, suffix):
+        """Assert that `string` ends with `suffix`.
+
+        Used to ignore an architecture-specific UTF-16 byte-order mark."""
+        self.assertEqual(string[-len(suffix) :], suffix)
+
     def test_read_text(self):
         self.assertEqual(
             resources.read_text(self.anchor01, 'utf-8.file'),
@@ -88,13 +94,13 @@ def test_read_text(self):
             ),
             '\x00\x01\x02\x03',
         )
-        self.assertEqual(
+        self.assertEndsWith(  # ignore the BOM
             resources.read_text(
                 self.anchor01,
                 'utf-16.file',
                 errors='backslashreplace',
             ),
-            'Hello, UTF-16 world!\n'.encode('utf-16').decode(
+            'Hello, UTF-16 world!\n'.encode('utf-16-le').decode(
                 errors='backslashreplace',
             ),
         )
@@ -140,9 +146,9 @@ def test_open_text(self):
             'utf-16.file',
             errors='backslashreplace',
         ) as f:
-            self.assertEqual(
+            self.assertEndsWith(  # ignore the BOM
                 f.read(),
-                'Hello, UTF-16 world!\n'.encode('utf-16').decode(
+                'Hello, UTF-16 world!\n'.encode('utf-16-le').decode(
                     errors='backslashreplace',
                 ),
             )

newsfragments/312.bugfix.rst

@@ -0,0 +1 @@
+Merged fix for UTF-16 BOM handling in functional tests.