tools/project-clang-format.py -> project/format.py

1 files changed, 180 insertions, 0 deletions

diff --git a/project/format.py b/project/format.py
new file mode 100644
index 0000000..5f24062
--- /dev/null
+++ b/project/format.py
@@ -0,0 +1,180 @@
+# Copyright (c) 2020 Egor Tensin <egor@tensin.name>
+# This file is part of the "cmake-common" project.
+# For details, see https://github.com/egor-tensin/cmake-common
+# Distributed under the MIT License.
+
+"""clang-format all C/C++ files in the project
+
+This script feeds every C/C++ file in the repository to clang-format, either
+printing a unified diff between the original and the formatted versions, or
+formatting the files in-place.
+"""
+
+import argparse
+import difflib
+import logging
+import os
+import sys
+
+from project.utils import cd, normalize_path, run_capture, setup_logging
+
+
+def read_file(path):
+    with open(path) as file:
+        return file.read()
+
+
+class ClangFormat:
+    def __init__(self, path, style):
+        self.path = path
+        self.style = style
+
+    def _get_command_line(self, paths, in_place=False):
+        cmd_line = [self.path, f"-style={self.style}"]
+        if in_place:
+            cmd_line.append("-i")
+        cmd_line.append("--")
+        cmd_line += list(paths)
+        return cmd_line
+
+    def format_in_place(self, paths):
+        run_capture(self._get_command_line(paths, in_place=True))
+
+    @staticmethod
+    def _show_diff(path, formatted):
+        original = read_file(path)
+        if original and not formatted:
+            # Assuming this file is ignored in .clang-format-ignore.
+            return True
+
+        original = original.split("\n")
+        formatted = formatted.split("\n")
+        original_lbl = f"{path} (original)"
+        formatted_lbl = f"{path} (formatted)"
+
+        diff = difflib.unified_diff(
+            original,
+            formatted,
+            fromfile=original_lbl,
+            tofile=formatted_lbl,
+            lineterm="",
+        )
+
+        clean = True
+        for line in diff:
+            clean = False
+            print(line)
+        return clean
+
+    def show_diff(self, paths):
+        clean = True
+        for path in paths:
+            formatted = run_capture(self._get_command_line([path]))
+            clean = self._show_diff(path, formatted) and clean
+        return clean
+
+
+def git_root_dir():
+    cmd_line = ["git", "rev-parse", "--show-toplevel"]
+    root_dir = run_capture(cmd_line)
+    if root_dir[-1] != "\n":
+        raise RuntimeError("git rev-parse --show-toplevel should append a newline?")
+    return root_dir[:-1]
+
+
+def list_git_files():
+    cmd_line = ["git", "ls-tree", "-r", "-z", "--name-only", "HEAD"]
+    repo_files = run_capture(cmd_line)
+    repo_files = repo_files.split("\0")
+    return repo_files
+
+
+def list_all_files():
+    return (normalize_path(path) for path in list_git_files())
+
+
+def excluded(path, exclude):
+    for entry in exclude:
+        if entry == os.path.commonpath((path, entry)):
+            return True
+    return False
+
+
+def filter_files(paths, exclude):
+    if not exclude:
+        return paths
+    return (path for path in paths if not excluded(path, exclude))
+
+
+CPP_FILE_EXTENSIONS = set(
+    (".c", ".h", ".cc", ".hh", ".cpp", ".hpp", ".cxx", ".hxx", ".cp", ".c++")
+)
+
+
+def list_cpp_files():
+    for path in list_all_files():
+        ext = os.path.splitext(path)[1].lower()
+        if ext in CPP_FILE_EXTENSIONS:
+            yield path
+
+
+DEFAULT_VERSION = "clang-format"
+DEFAULT_STYLE = "file"
+
+
+def process_cpp_files(
+    version=DEFAULT_VERSION, style=DEFAULT_STYLE, in_place=False, exclude=None
+):
+    clang_format = ClangFormat(version, style)
+    with cd(git_root_dir()):
+        cpp_files = filter_files(list_cpp_files(), exclude)
+        if in_place:
+            clang_format.format_in_place(cpp_files)
+        else:
+            if not clang_format.show_diff(cpp_files):
+                sys.exit(1)
+
+
+def parse_args(argv=None):
+    if argv is None:
+        argv = sys.argv[1:]
+
+    parser = argparse.ArgumentParser(
+        description=__doc__, formatter_class=argparse.RawDescriptionHelpFormatter
+    )
+
+    parser.add_argument(
+        "-b",
+        "--clang-format",
+        dest="version",
+        default=DEFAULT_VERSION,
+        help="clang-format executable file path",
+    )
+    parser.add_argument(
+        "-s",
+        "--style",
+        default=DEFAULT_STYLE,
+        help="clang-format -style parameter argument",
+    )
+    parser.add_argument(
+        "-i", "--in-place", action="store_true", help="edit the files in-place"
+    )
+    parser.add_argument(
+        "-e",
+        "--exclude",
+        nargs="*",
+        type=normalize_path,
+        help="files or directories to exclude",
+    )
+
+    return parser.parse_args(argv)
+
+
+def main(argv=None):
+    args = parse_args(argv)
+    with setup_logging():
+        process_cpp_files(**vars(args))
+
+
+if __name__ == "__main__":
+    main()