clang-format hook support --verbose output

README.md

@@ -5,18 +5,26 @@
 [![codecov](https://codecov.io/gh/cpp-linter/cpp-linter-hooks/branch/main/graph/badge.svg?token=L74Z3HZ4Y5)](https://codecov.io/gh/cpp-linter/cpp-linter-hooks)
 [![Test](https://github.com/cpp-linter/cpp-linter-hooks/actions/workflows/test.yml/badge.svg)](https://github.com/cpp-linter/cpp-linter-hooks/actions/workflows/test.yml)
 [![CodeQL](https://github.com/cpp-linter/cpp-linter-hooks/actions/workflows/codeql.yml/badge.svg)](https://github.com/cpp-linter/cpp-linter-hooks/actions/workflows/codeql.yml)
-<!-- [![PyPI - Downloads](https://img.shields.io/pypi/dw/cpp-linter-hooks)](https://pypi.org/project/cpp-linter-hooks/) -->
 
-cpp-linter-hooks is a [pre-commit](https://pre-commit.com/) hook that uses `clang-format` and `clang-tidy` to format C/C++ code.
+A powerful [pre-commit](https://pre-commit.com/) hook for auto-formatting and linting C/C++ code with `clang-format` and `clang-tidy`.
 
-> [!NOTE]
-> This hook automatically downloads specific versions of `clang-format` or `clang-tidy` [static-binaries](https://github.com/cpp-linter/clang-tools-static-binaries) and installs them on your system.
+## Table of Contents
 
-## Usage
+- [Quick Start](#quick-start)
+  - [Custom Configuration Files](#custom-configuration-files)
+  - [Custom Clang Tool Version](#custom-clang-tool-version)
+- [Output](#output)
+  - [clang-format Output](#clang-format-output)
+  - [clang-tidy Output](#clang-tidy-output)
+- [Troubleshooting](#troubleshooting)
+  - [Performance Optimization](#performance-optimization)
+  - [Verbose Output](#verbose-output)
+- [Contributing](#contributing)
+- [License](#license)
 
-To use cpp-linter-hooks, add the following configuration to your `.pre-commit-config.yaml`:
+## Quick Start
 
-### Basic Configuration
+Add this configuration to your `.pre-commit-config.yaml` file:
 
 ```yaml
 repos:
@@ -29,7 +37,7 @@ repos:
         args: [--checks='boost-*,bugprone-*,performance-*,readability-*,portability-*,modernize-*,clang-analyzer-*,cppcoreguidelines-*']
 ```
 
-### Custom Configuration
+### Custom Configuration Files
 
 To use custom configurations like `.clang-format` and `.clang-tidy`:
 
@@ -44,6 +52,8 @@ repos:
         args: [--checks=.clang-tidy] # Loads checks from .clang-tidy file
 ```
 
+### Custom Clang Tool Version
+
 To use specific versions of [clang-tools](https://github.com/cpp-linter/clang-tools-pip?tab=readme-ov-file#supported-versions):
 
 ```yaml
@@ -57,33 +67,9 @@ repos:
         args: [--checks=.clang-tidy, --version=18] # Specifies version
 ```
 
-> [!IMPORTANT]
-> If your `pre-commit` runs longer than expected, it is highly recommended to add `files` in `.pre-commit-config.yaml` to limit the scope of the hook. This helps improve performance by reducing the number of files being checked and avoids unnecessary processing. Here's an example configuration:
-
-
-```yaml
-- repo: https://github.com/cpp-linter/cpp-linter-hooks
-  rev: v0.8.1
-  hooks:
-    - id: clang-format
-      args: [--style=file, --version=18]
-      files: ^(src|include)/.*\.(cpp|cc|cxx|h|hpp)$ # Limits to specific dirs and file types
-    - id: clang-tidy
-      args: [--checks=.clang-tidy, --version=18]
-      files: ^(src|include)/.*\.(cpp|cc|cxx|h|hpp)$
-```
-
-Alternatively, if you want to run the hooks manually on only the changed files, you can use the following command:
-
-```bash
-pre-commit run --files $(git diff --name-only)
-```
-
-This approach ensures that only modified files are checked, further speeding up the linting process during development.
-
 ## Output
 
-### clang-format Example
+### clang-format Output
 
 ```bash
 clang-format.............................................................Failed
@@ -106,8 +92,8 @@ Here’s a sample diff showing the formatting applied:
 +  return 0;
 +}
 ```
-
-Use `--dry-run` in `args` of `clang-format` to print instead of changing the format, e.g.:
+> [!NOTE]
+> Use `--dry-run` in `args` of `clang-format` to print instead of changing the format, e.g.:
 
 ```bash
 clang-format.............................................................Failed
@@ -134,7 +120,7 @@ int main() {for (;;) break; printf("Hello world!\n");return 0;}
                                                               ^
 ```
 
-### clang-tidy Example
+### clang-tidy Output
 
 ```bash
 clang-tidy...............................................................Failed
@@ -151,10 +137,51 @@ Use -header-filter=.* to display errors from all non-system headers. Use -system
 
 ```
 
+## Troubleshooting
+
+### Performance Optimization
+
+> [!WARNING]
+> If your `pre-commit` runs longer than expected, it is highly recommended to add `files` in `.pre-commit-config.yaml` to limit the scope of the hook. This helps improve performance by reducing the number of files being checked and avoids unnecessary processing. Here's an example configuration:
+
+```yaml
+- repo: https://github.com/cpp-linter/cpp-linter-hooks
+  rev: v0.8.1
+  hooks:
+    - id: clang-format
+      args: [--style=file, --version=18]
+      files: ^(src|include)/.*\.(cpp|cc|cxx|h|hpp)$ # Limits to specific dirs and file types
+    - id: clang-tidy
+      args: [--checks=.clang-tidy, --version=18]
+      files: ^(src|include)/.*\.(cpp|cc|cxx|h|hpp)$
+```
+
+Alternatively, if you want to run the hooks manually on only the changed files, you can use the following command:
+
+```bash
+pre-commit run --files $(git diff --name-only)
+```
+
+This approach ensures that only modified files are checked, further speeding up the linting process during development.
+
+### Verbose Output
+
+> [!NOTE]
+> Use `-v` or `--verbose` in `args` of `clang-format` to show the list of processed files e.g.:
+
+```yaml
+repos:
+  - repo: https://github.com/cpp-linter/cpp-linter-hooks
+    rev: v0.8.1
+    hooks:
+      - id: clang-format
+        args: [--style=file, --version=18, --verbose]   # Add -v or --verbose for detailed output
+```
+
 ## Contributing
 
 We welcome contributions! Whether it's fixing issues, suggesting improvements, or submitting pull requests, your support is greatly appreciated.
 
 ## License
 
-cpp-linter-hooks is licensed under the [MIT License](LICENSE)
+This project is licensed under the [MIT License](LICENSE).

cpp_linter_hooks/clang_format.py

@@ -1,4 +1,5 @@
 import subprocess
+import sys
 from argparse import ArgumentParser
 from typing import Tuple
 
@@ -7,34 +8,67 @@
 
 parser = ArgumentParser()
 parser.add_argument("--version", default=DEFAULT_CLANG_VERSION)
+parser.add_argument(
+    "-v", "--verbose", action="store_true", help="Enable verbose output"
+)
 
 
 def run_clang_format(args=None) -> Tuple[int, str]:
     hook_args, other_args = parser.parse_known_args(args)
     path = ensure_installed("clang-format", hook_args.version)
     command = [str(path), "-i"]
+
+    # Add verbose flag if requested
+    if hook_args.verbose:
+        command.append("--verbose")
+
     command.extend(other_args)
 
-    retval = 0
-    output = ""
     try:
+        # Run the clang-format command with captured output
+        sp = subprocess.run(
+            command,
+            stdout=subprocess.PIPE,
+            stderr=subprocess.PIPE,
+            encoding="utf-8",
+        )
+
+        # Combine stdout and stderr for complete output
+        output = (sp.stdout or "") + (sp.stderr or "")
+
+        # Handle special case for dry-run mode
         if "--dry-run" in command:
-            sp = subprocess.run(command, stdout=subprocess.PIPE, encoding="utf-8")
-            retval = -1  # Not a fail just identify it's a dry-run.
-            output = sp.stdout
+            retval = -1  # Special code to identify dry-run mode
         else:
-            retval = subprocess.run(command, stdout=subprocess.PIPE).returncode
+            retval = sp.returncode
+
+        # Print verbose information if requested
+        if hook_args.verbose:
+            _print_verbose_info(command, retval, output)
+
         return retval, output
-    except FileNotFoundError as stderr:
-        retval = 1
-        return retval, str(stderr)
+
+    except FileNotFoundError as e:
+        return 1, str(e)
+
+
+def _print_verbose_info(command: list, retval: int, output: str) -> None:
+    """Print verbose debugging information to stderr."""
+    print(f"Command executed: {' '.join(command)}", file=sys.stderr)
+    print(f"Exit code: {retval}", file=sys.stderr)
+    if output.strip():
+        print(f"Output: {output}", file=sys.stderr)
 
 
 def main() -> int:
-    retval, output = run_clang_format()
-    if retval != 0:
+    retval, output = run_clang_format()  # pragma: no cover
+
+    # Print output for errors, but not for dry-run mode
+    if retval != 0 and retval != -1 and output.strip():  # pragma: no cover
         print(output)
-    return retval
+
+    # Convert dry-run special code to success
+    return 0 if retval == -1 else retval  # pragma: no cover
 
 
 if __name__ == "__main__":

pyproject.toml

@@ -6,7 +6,7 @@ requires-python = ">=3.9"
 
 [project]
 name = "cpp_linter_hooks"
-description = "Automatically check c/c++ code with clang-format and clang-tidy"
+description = "Automatically formats and lints C/C++ code using clang-format and clang-tidy"
 readme = "README.md"
 keywords = ["clang", "clang-format", "clang-tidy", "pre-commit", "pre-commit-hooks"]
 license = "MIT"

testing/pre-commit-config-verbose.yaml

@@ -0,0 +1,11 @@
+repos:
+  - repo: .
+    rev: HEAD
+    hooks:
+      - id: clang-format
+        args: [--style=file, --version=16, --verbose]  # test with verbose output
+  - repo: .
+    rev: HEAD
+    hooks:
+      - id: clang-format
+        args: [--style=file, --version=16, -v]  # test with verbose output

testing/run.sh

@@ -1,22 +1,40 @@
-rm -f result.txt
+#!/bin/bash
+echo "==========================="
+echo "Test pre-commit-config.yaml"
+echo "==========================="
+pre-commit clean
+pre-commit run -c testing/pre-commit-config.yaml --files testing/main.c | tee -a result.txt || true
 git restore testing/main.c
 
-for config in testing/pre-commit-config.yaml testing/pre-commit-config-version.yaml; do
-    pre-commit clean
-    pre-commit run -c $config --files testing/main.c | tee -a result.txt || true
-    git restore testing/main.c
-done
+echo "===================================="
+echo "Test pre-commit-config-version.yaml"
+echo "===================================="
+pre-commit clean
+pre-commit run -c testing/pre-commit-config-version.yaml --files testing/main.c | tee -a result.txt || true
+git restore testing/main.c
+
+echo "===================================="
+echo "Test pre-commit-config-verbose.yaml"
+echo "===================================="
+pre-commit clean
+pre-commit run -c testing/pre-commit-config-verbose.yaml --files testing/main.c | tee -a result.txt || true
+git restore testing/main.c
+
+echo "=================================================================================="
+echo "print result.txt"
+cat result.txt
+echo "=================================================================================="
 
 failed_cases=`grep -c "Failed" result.txt`
 
 echo $failed_cases " cases failed."
 
-if [ $failed_cases -eq 9 ]; then
+if [ $failed_cases -eq 10 ]; then
     echo "=============================="
     echo "Test cpp-linter-hooks success."
     echo "=============================="
-    exit 0
     rm result.txt
+    exit 0
 else
     echo "============================="
     echo "Test cpp-linter-hooks failed."

tests/test_clang_format.py

@@ -64,3 +64,35 @@ def test_run_clang_format_dry_run(args, expected_retval, tmp_path):
     test_file = tmp_path / "main.c"
     ret, _ = run_clang_format(["--dry-run", str(test_file)])
     assert ret == -1  # Dry run should not fail
+
+
+def test_run_clang_format_verbose(tmp_path):
+    """Test that verbose option works and provides detailed output."""
+    # copy test file to tmp_path to prevent modifying repo data
+    test_file = tmp_path / "main.c"
+    test_file.write_bytes(Path("testing/main.c").read_bytes())
+
+    # Test with verbose flag
+    ret, _ = run_clang_format(["--verbose", "--style=Google", str(test_file)])
+
+    # Should succeed
+    assert ret == 0
+    # Should have verbose output (will be printed to stderr, not returned)
+    # The function should still return successfully
+    assert test_file.read_text() == Path("testing/good.c").read_text()
+
+
+def test_run_clang_format_verbose_error(tmp_path):
+    """Test that verbose option provides useful error information."""
+    test_file = tmp_path / "main.c"
+    test_file.write_bytes(Path("testing/main.c").read_bytes())
+
+    # Test with verbose flag and invalid style
+    ret, output = run_clang_format(
+        ["--verbose", "--style=InvalidStyle", str(test_file)]
+    )
+
+    # Should fail
+    assert ret != 0
+    # Should have error message in output
+    assert "Invalid value for -style" in output