Allow # Ignore copy (#27328)

* fix

---------

Co-authored-by: ydshieh <ydshieh@users.noreply.github.com>
Co-authored-by: Arthur <48595927+ArthurZucker@users.noreply.github.com>

tests/repo_utils/test_check_copies.py

@@ -95,13 +95,156 @@ class BertCopyModel(BertCopyPreTrainedModel):
 """
 
 
+MOCK_DUMMY_BERT_CODE_MATCH = """
+class BertDummyModel:
+    attr_1 = 1
+    attr_2 = 2
+
+    def __init__(self, a=1, b=2):
+        self.a = a
+        self.b = b
+
+    # Copied from transformers.models.dummy_gpt2.modeling_dummy_gpt2.GPT2DummyModel.forward
+    def forward(self, c):
+        return 1
+
+    def existing_common(self, c):
+        return 4
+
+    def existing_diff_to_be_ignored(self, c):
+        return 9
+"""
+
+
+MOCK_DUMMY_ROBERTA_CODE_MATCH = """
+# Copied from transformers.models.dummy_bert_match.modeling_dummy_bert_match.BertDummyModel with BertDummy->RobertaBertDummy
+class RobertaBertDummyModel:
+
+    attr_1 = 1
+    attr_2 = 2
+
+    def __init__(self, a=1, b=2):
+        self.a = a
+        self.b = b
+
+    # Ignore copy
+    def only_in_roberta_to_be_ignored(self, c):
+        return 3
+
+    # Copied from transformers.models.dummy_gpt2.modeling_dummy_gpt2.GPT2DummyModel.forward
+    def forward(self, c):
+        return 1
+
+    def existing_common(self, c):
+        return 4
+
+    # Ignore copy
+    def existing_diff_to_be_ignored(self, c):
+        return 6
+"""
+
+
+MOCK_DUMMY_BERT_CODE_NO_MATCH = """
+class BertDummyModel:
+    attr_1 = 1
+    attr_2 = 2
+
+    def __init__(self, a=1, b=2):
+        self.a = a
+        self.b = b
+
+    # Copied from transformers.models.dummy_gpt2.modeling_dummy_gpt2.GPT2DummyModel.forward
+    def forward(self, c):
+        return 1
+
+    def only_in_bert(self, c):
+        return 7
+
+    def existing_common(self, c):
+        return 4
+
+    def existing_diff_not_ignored(self, c):
+        return 8
+
+    def existing_diff_to_be_ignored(self, c):
+        return 9
+"""
+
+
+MOCK_DUMMY_ROBERTA_CODE_NO_MATCH = """
+# Copied from transformers.models.dummy_bert_no_match.modeling_dummy_bert_no_match.BertDummyModel with BertDummy->RobertaBertDummy
+class RobertaBertDummyModel:
+
+    attr_1 = 1
+    attr_2 = 3
+
+    def __init__(self, a=1, b=2):
+        self.a = a
+        self.b = b
+
+    # Ignore copy
+    def only_in_roberta_to_be_ignored(self, c):
+        return 3
+
+    # Copied from transformers.models.dummy_gpt2.modeling_dummy_gpt2.GPT2DummyModel.forward
+    def forward(self, c):
+        return 1
+
+    def only_in_roberta_not_ignored(self, c):
+        return 2
+
+    def existing_common(self, c):
+        return 4
+
+    def existing_diff_not_ignored(self, c):
+        return 5
+
+    # Ignore copy
+    def existing_diff_to_be_ignored(self, c):
+        return 6
+"""
+
+
+EXPECTED_REPLACED_CODE = """
+# Copied from transformers.models.dummy_bert_no_match.modeling_dummy_bert_no_match.BertDummyModel with BertDummy->RobertaBertDummy
+class RobertaBertDummyModel:
+    attr_1 = 1
+    attr_2 = 2
+
+    def __init__(self, a=1, b=2):
+        self.a = a
+        self.b = b
+
+    # Copied from transformers.models.dummy_gpt2.modeling_dummy_gpt2.GPT2DummyModel.forward
+    def forward(self, c):
+        return 1
+
+    def only_in_bert(self, c):
+        return 7
+
+    def existing_common(self, c):
+        return 4
+
+    def existing_diff_not_ignored(self, c):
+        return 8
+
+    # Ignore copy
+    def existing_diff_to_be_ignored(self, c):
+        return 6
+
+    # Ignore copy
+    def only_in_roberta_to_be_ignored(self, c):
+        return 3
+"""
+
+
 def replace_in_file(filename, old, new):
     with open(filename, "r", encoding="utf-8") as f:
         content = f.read()
 
     content = content.replace(old, new)
 
-    with open(filename, "w", encoding="utf-8") as f:
+    with open(filename, "w", encoding="utf-8", newline="\n") as f:
         f.write(content)
 
 
@@ -117,11 +260,18 @@ def create_tmp_repo(tmp_dir):
     model_dir = tmp_dir / "src" / "transformers" / "models"
     model_dir.mkdir(parents=True, exist_ok=True)
 
-    models = {"bert": MOCK_BERT_CODE, "bertcopy": MOCK_BERT_COPY_CODE}
+    models = {
+        "bert": MOCK_BERT_CODE,
+        "bertcopy": MOCK_BERT_COPY_CODE,
+        "dummy_bert_match": MOCK_DUMMY_BERT_CODE_MATCH,
+        "dummy_roberta_match": MOCK_DUMMY_ROBERTA_CODE_MATCH,
+        "dummy_bert_no_match": MOCK_DUMMY_BERT_CODE_NO_MATCH,
+        "dummy_roberta_no_match": MOCK_DUMMY_ROBERTA_CODE_NO_MATCH,
+    }
     for model, code in models.items():
         model_subdir = model_dir / model
         model_subdir.mkdir(exist_ok=True)
-        with open(model_subdir / f"modeling_{model}.py", "w", encoding="utf-8") as f:
+        with open(model_subdir / f"modeling_{model}.py", "w", encoding="utf-8", newline="\n") as f:
             f.write(code)
 
 
@@ -176,11 +326,47 @@ class CopyCheckTester(unittest.TestCase):
                 diffs = is_copy_consistent(file_to_check)
                 self.assertEqual(diffs, [["models.bert.modeling_bert.BertModel", 22]])
 
-                diffs = is_copy_consistent(file_to_check, overwrite=True)
+                _ = is_copy_consistent(file_to_check, overwrite=True)
 
                 with open(file_to_check, "r", encoding="utf-8") as f:
                     self.assertEqual(f.read(), MOCK_BERT_COPY_CODE)
 
+    def test_is_copy_consistent_with_ignored_match(self):
+        path_to_check = ["src", "transformers", "models", "dummy_roberta_match", "modeling_dummy_roberta_match.py"]
+        with tempfile.TemporaryDirectory() as tmp_folder:
+            # Base check
+            create_tmp_repo(tmp_folder)
+            with patch_transformer_repo_path(tmp_folder):
+                file_to_check = os.path.join(tmp_folder, *path_to_check)
+                diffs = is_copy_consistent(file_to_check)
+                self.assertEqual(diffs, [])
+
+    def test_is_copy_consistent_with_ignored_no_match(self):
+        path_to_check = [
+            "src",
+            "transformers",
+            "models",
+            "dummy_roberta_no_match",
+            "modeling_dummy_roberta_no_match.py",
+        ]
+        with tempfile.TemporaryDirectory() as tmp_folder:
+            # Base check with an inconsistency
+            create_tmp_repo(tmp_folder)
+            with patch_transformer_repo_path(tmp_folder):
+                file_to_check = os.path.join(tmp_folder, *path_to_check)
+
+                diffs = is_copy_consistent(file_to_check)
+                # line 6: `attr_2 = 3` in `MOCK_DUMMY_ROBERTA_CODE_NO_MATCH`.
+                # (which has a leading `\n`.)
+                self.assertEqual(
+                    diffs, [["models.dummy_bert_no_match.modeling_dummy_bert_no_match.BertDummyModel", 6]]
+                )
+
+                _ = is_copy_consistent(file_to_check, overwrite=True)
+
+                with open(file_to_check, "r", encoding="utf-8") as f:
+                    self.assertEqual(f.read(), EXPECTED_REPLACED_CODE)
+
     def test_convert_to_localized_md(self):
         localized_readme = check_copies.LOCALIZED_READMES["README_zh-hans.md"]