[Modular] skip modular checks based on diff (#36130)

skip modular checks based on diff

utils/check_modular_conversion.py

@@ -2,6 +2,7 @@ import argparse
 import difflib
 import glob
 import logging
+import subprocess
 from io import StringIO
 
 from create_dependency_mapping import find_priority_list
@@ -61,6 +62,56 @@ def compare_files(modular_file_path, fix_and_overwrite=False):
     return diff
 
 
+def get_models_in_diff():
+    """
+    Finds all models that have been modified in the diff.
+
+    Returns:
+        A set containing the names of the models that have been modified (e.g. {'llama', 'whisper'}).
+    """
+    fork_point_sha = subprocess.check_output("git merge-base main HEAD".split()).decode("utf-8")
+    modified_files = (
+        subprocess.check_output(f"git diff --diff-filter=d --name-only {fork_point_sha}".split())
+        .decode("utf-8")
+        .split()
+    )
+
+    # Matches both modelling files and tests
+    relevant_modified_files = [x for x in modified_files if "/models/" in x and x.endswith(".py")]
+    model_names = set()
+    for file_path in relevant_modified_files:
+        model_name = file_path.split("/")[-2]
+        model_names.add(model_name)
+    return model_names
+
+
+def guaranteed_no_diff(modular_file_path, dependencies, models_in_diff):
+    """
+    Returns whether it is guaranteed to have no differences between the modular file and the modeling file.
+
+    Model is in the diff -> not guaranteed to have no differences
+    Dependency is in the diff -> not guaranteed to have no differences
+    Otherwise -> guaranteed to have no differences
+
+    Args:
+        modular_file_path: The path to the modular file.
+        dependencies: A dictionary containing the dependencies of each modular file.
+        models_in_diff: A set containing the names of the models that have been modified.
+
+    Returns:
+        A boolean indicating whether the model (code and tests) is guaranteed to have no differences.
+    """
+    model_name = modular_file_path.rsplit("modular_", 1)[1].replace(".py", "")
+    if model_name in models_in_diff:
+        return False
+    for dep in dependencies[modular_file_path]:
+        # two possible patterns: `transformers.models.model_name.(...)` or `model_name.(...)`
+        dependency_model_name = dep.split(".")[-2]
+        if dependency_model_name in models_in_diff:
+            return False
+    return True
+
+
 if __name__ == "__main__":
     parser = argparse.ArgumentParser(description="Compare modular_xxx.py files with modeling_xxx.py files.")
     parser.add_argument(
@@ -72,9 +123,32 @@ if __name__ == "__main__":
     args = parser.parse_args()
     if args.files == ["all"]:
         args.files = glob.glob("src/transformers/models/**/modular_*.py", recursive=True)
+
+    # Assuming there is a topological sort on the dependency mapping: if the file being checked and its dependencies
+    # are not in the diff, then there it is guaranteed to have no differences. If no models are in the diff, then this
+    # script will do nothing.
+    models_in_diff = get_models_in_diff()
+    if not models_in_diff:
+        console.print("[bold green]No models files or model tests in the diff, skipping modular checks[/bold green]")
+        exit(0)
+
+    skipped_models = set()
     non_matching_files = 0
-    for modular_file_path in find_priority_list(args.files):
+    ordered_files, dependencies = find_priority_list(args.files)
+    for modular_file_path in ordered_files:
+        is_guaranteed_no_diff = guaranteed_no_diff(modular_file_path, dependencies, models_in_diff)
+        if is_guaranteed_no_diff:
+            model_name = modular_file_path.rsplit("modular_", 1)[1].replace(".py", "")
+            skipped_models.add(model_name)
+            continue
         non_matching_files += compare_files(modular_file_path, args.fix_and_overwrite)
+        models_in_diff = get_models_in_diff()  # When overwriting, the diff changes
 
     if non_matching_files and not args.fix_and_overwrite:
         raise ValueError("Some diff and their modeling code did not match.")
+
+    if skipped_models:
+        console.print(
+            f"[bold green]Skipped {len(skipped_models)} models and their dependencies that are not in the diff: "
+            f"{', '.join(skipped_models)}[/bold green]"
+        )