chore: import upstream snapshot with attribution

scripts/file_linter.py

@@ -0,0 +1,49 @@
+import os
+import subprocess
+import sys
+
+print("Python {}.{}.{}".format(*sys.version_info))  # Python 3.8
+with open("git_diff.txt") as in_file:
+    modified_files = sorted(in_file.read().splitlines())
+    print("{} files were modified.".format(len(modified_files)))
+
+    cpp_exts = tuple(".c .c++ .cc .cpp .cu .cuh .cxx .h .h++ .hh .hpp .hxx".split())
+    cpp_files = [file for file in modified_files if file.lower().endswith(cpp_exts)]
+    print(f"{len(cpp_files)} C++ files were modified.")
+    if not cpp_files:
+        sys.exit(0)
+
+    subprocess.run(
+        [
+            "clang-tidy",
+            "--fix",
+            "-p=build",
+            "--extra-arg=-std=c++11",
+            *cpp_files,
+            "--",
+        ],
+        check=True,
+        text=True,
+        stderr=subprocess.STDOUT,
+    )
+    subprocess.run(
+        ["clang-format", "-i", "-style=file", *cpp_files],
+        check=True,
+        text=True,
+        stderr=subprocess.STDOUT,
+    )
+    upper_files = [file for file in cpp_files if file != file.lower()]
+    if upper_files:
+        print(f"{len(upper_files)} files contain uppercase characters:")
+        print("\n".join(upper_files) + "\n")
+    space_files = [file for file in cpp_files if " " in file or "-" in file]
+    if space_files:
+        print(f"{len(space_files)} files contain space or dash characters:")
+        print("\n".join(space_files) + "\n")
+    nodir_files = [file for file in cpp_files if file.count(os.sep) != 1]
+    if nodir_files:
+        print(f"{len(nodir_files)} files are not in one and only one directory:")
+        print("\n".join(nodir_files) + "\n")
+    bad_files = len(upper_files + space_files + nodir_files)
+    if bad_files:
+        sys.exit(bad_files)