Support for Windows in check_copies (#7316)

utils/check_copies.py

@@ -40,7 +40,7 @@ def find_code_in_transformers(object_name):
             f"`object_name` should begin with the name of a module of transformers but got {object_name}."
         )
 
-    with open(os.path.join(TRANSFORMERS_PATH, f"{module}.py"), "r") as f:
+    with open(os.path.join(TRANSFORMERS_PATH, f"{module}.py"), "r", encoding="utf-8") as f:
         lines = f.readlines()
 
     # Now let's find the class / func in the code!
@@ -80,10 +80,10 @@ def blackify(code):
         code = f"class Bla:\n{code}"
     with tempfile.TemporaryDirectory() as d:
         fname = os.path.join(d, "tmp.py")
-        with open(fname, "w") as f:
+        with open(fname, "w", encoding="utf-8") as f:
             f.write(code)
         os.system(f"black -q --line-length 119 --target-version py35 {fname}")
-        with open(fname, "r") as f:
+        with open(fname, "r", encoding="utf-8") as f:
             result = f.read()
             return result[len("class Bla:\n") :] if has_indent else result
 
@@ -94,7 +94,7 @@ def is_copy_consistent(filename, overwrite=False):
 
     Return the differences or overwrites the content depending on `overwrite`.
     """
-    with open(filename) as f:
+    with open(filename, "r", encoding="utf-8") as f:
         lines = f.readlines()
     found_diff = False
     line_index = 0
@@ -152,7 +152,7 @@ def is_copy_consistent(filename, overwrite=False):
     if overwrite and found_diff:
         # Warn the user a file has been modified.
         print(f"Detected changes, rewriting {filename}.")
-        with open(filename, "w") as f:
+        with open(filename, "w", encoding="utf-8") as f:
             f.writelines(lines)
     return not found_diff