repo.bzl: Run patch -p1 in _apply_patch on Windows

The patch command in MSYS is version 2.7, which also supports renaming.

PiperOrigin-RevId: 254022429

third_party/repo.bzl

@@ -61,12 +61,13 @@ def _repos_are_siblings():
     return Label("@foo//bar").workspace_root.startswith("../")
 
 # Apply a patch_file to the repository root directory
-# Runs 'git apply'
+# Runs 'git apply' on Unix, 'patch -p1' on Windows.
 def _apply_patch(ctx, patch_file):
-    cmd = _wrap_bash_cmd(
-        ctx,
-        ["git", "apply", "-v", ctx.path(patch_file)],
-    )
+    if _is_windows(ctx):
+        patch_command = ["patch", "-p1", "-d", ctx.path("."), "-i", ctx.path(patch_file)]
+    else:
+        patch_command = ["git", "apply", "-v", ctx.path(patch_file)]
+    cmd = _wrap_bash_cmd(ctx, patch_command)
     _execute_and_check_ret_code(ctx, cmd)
 
 def _apply_delete(ctx, paths):