Docstring Generator Extension

C++ Tests Build Extension PyPI version Python versions License: MIT

docstring_generator_ext is a high-performance Python extension written in C++ (using pybind11) designed to automatically generate and inject docstrings into Python source files. It leverages Python's ast module to extract type-hint information and function signatures to create well-formatted docstrings in various styles.

Features

  • Automatic Docstring Injection: Parses Python files and inserts docstrings for functions and methods.
  • Async-function support: Handles both def and async def functions transparently.
  • Type-Hint Awareness: Extracts type information from annotations and default values.
  • Multiple Styles: Supports popular docstring formats:
    • reST (reStructuredText)
    • Google style
    • NumPy style
  • Format-style detection: Automatically detects the style of an existing docstring and refuses to silently mix styles unless allow_overwrite=True is passed.
  • Style conversion: With allow_overwrite=True, converts a docstring written in one style to another in a single call.
  • Exception detection: Analyses the function body with Python's ast module to identify raised exceptions and include them in the docstring.
  • Docstring coverage auditing: check_docstring() reports how many functions in a file have complete, partial, or missing docstrings without modifying the file.
  • High Performance: Core logic implemented in C++ for fast processing.
  • Preserves Existing Content: Keeps manually written descriptions across re-runs using special in-docstring markers:
    • $N binds the text on that line to the N-th function parameter.
    • >> provides the return-value description.

Installation

Prerequisites

  • Python 3.13 or higher
  • A C++ compiler with C++20 support (e.g., GCC, Clang, or MSVC)
  • pybind11

Building from Source

  1. Clone the repository:

    git clone https://github.com/FelixTheC/docstring_generator_ext.git
cd docstring_generator_ext

  2. Install the build package:

    pip install build

  3. Build the package:

    python -m build

  4. Install the built wheel:

    pip install dist/docstring_generator_ext-*.whl

Usage

After installation, you can use the extension in your Python scripts:

import docstring_generator_ext

# Path to the Python file you want to process
file_path = "path/to/your_script.py"

# Choose a style: GOOGLE, NUMPY, or reST
style = docstring_generator_ext.DocstringFormatStyle.GOOGLE

# Generate and inject docstrings
docstring_generator_ext.parse_file(file_path, style)

Overwriting an existing docstring format

By default, parse_file refuses to overwrite a docstring that was already written in a different style than the one you requested, and will print a warning instead. Pass allow_overwrite=True to let the extension convert the existing docstring to the new style:

import docstring_generator_ext

file_path = "path/to/your_script.py"
style = docstring_generator_ext.DocstringFormatStyle.NUMPY

# Convert any existing docstring style to NUMPY — previous style will be removed
docstring_generator_ext.parse_file(file_path, style, allow_overwrite=True)

Auditing docstring coverage

You can audit an existing file to see how well its functions are documented, without making any changes:

import docstring_generator_ext

# Path to the Python file you want to audit
file_path = "path/to/your_script.py"

# Returns a dict with docstring coverage statistics
result = docstring_generator_ext.check_docstring(file_path)

print(f"Functions checked  : {result['num_functions_checked']}")
print(f"Complete docstrings: {result['complete_docstrings']}")
print(f"Partial docstrings : {result['partial_docstrings']}")
print(f"No docstrings      : {result['no_docstrings']}")

The returned dictionary always contains four keys:

Key Description
num_functions_checked Total number of functions/methods found in the file
complete_docstrings Functions whose docstring fully matches the signature
partial_docstrings Functions with an incomplete or outdated docstring
no_docstrings Functions with no docstring at all

Docstring Styles

The extension provides an enum DocstringFormatStyle to choose the desired output:

  • docstring_generator_ext.DocstringFormatStyle.reST
  • docstring_generator_ext.DocstringFormatStyle.GOOGLE
  • docstring_generator_ext.DocstringFormatStyle.NUMPY

Preserving descriptions with special markers

When the extension processes a file that already contains docstrings, it tries to keep manually written descriptions in place. Two marker conventions are supported:

$N — argument description markers

Place a $ followed by the 1-based index of the parameter inside the docstring to bind a free-form description to that argument. The marker and the text on its line are extracted and attached to the corresponding parameter; the $N line is then removed from the generated docstring.

def add(a: int, b: int) -> int:
    """Add two numbers together.

    $1 The first operand.
    $2 The second operand.
    """
    return a + b

After the next parse_file run the descriptions will be wired to a and b automatically.

def add(a: int, b: int) -> int:
    """Add two numbers together.

    Args:
        a (int): The first operand.
        b (int): The second operand.
    Returns:
        int
    """
    return a + b

>> — return description marker

Place >> on its own line inside the docstring to provide the description for the return value. The text after >> on that line is extracted as the return description, and the marker line is removed.

def square(x: int) -> int:
    """Square a number.

    >> The squared value of x.
    """
    return x * x

After the next parse_file run the descriptions will be wired to Returns description automatically.

def square(x: int) -> int:
    """Square a number.

    Args:
        x (int):
    Returns:
        int: The squared value of x.
    """
    return x * x

C++20

The core of this extension is written in C++20 to take full advantage of the modern standard's best algorithms and features:

  • std::format: Used for clean, type-safe string formatting throughout the docstring generation logic.
  • Ranges & views: C++20 ranges enable expressive, composable data transformations without raw loops.
  • Concepts: Improve template code clarity and provide better compiler error messages.
  • std::span: Provides safe, bounds-checked views over contiguous data without ownership overhead.

Compiler Requirements

Building from source requires a C++ compiler with full C++20 support:

Platform Minimum version
Linux GCC 11+ / Clang 14+
macOS Apple Clang 15+ / GCC 13+ (via Homebrew)
Windows MSVC 2022 (19.30+)

Pre-built wheels on PyPI are compiled with C++20 enabled and require no special toolchain on the user's side.

Authors

  • FelixTheC

License

This project is licensed under the MIT License - see the LICENSE.md file for details.

Key dates

PyPI data
Data sourced directly from PyPI's database.
  • Released:
Newer release available (2.1.0)

1 maintainer

PyPI data
Data sourced directly from PyPI's database.
Avatar for FelixTheC from gravatar.com FelixTheC

Credits

Author: FelixTheC

Requires

Python >=3.13

Classifiers

Report project as malware

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

docstring_generator_ext-2.0.9.tar.gz (16.6 kB view details)

Uploaded Source

Built Distributions

If you're not sure about the file name format, learn more about wheel file names.

docstring_generator_ext-2.0.9-cp313-cp313-win_amd64.whl (252.6 kB view details)

Uploaded CPython 3.13Windows x86-64

docstring_generator_ext-2.0.9-cp313-cp313-manylinux_2_27_x86_64.manylinux_2_28_x86_64.whl (661.9 kB view details)

Uploaded CPython 3.13manylinux: glibc 2.27+ x86-64manylinux: glibc 2.28+ x86-64

docstring_generator_ext-2.0.9-cp313-cp313-macosx_13_0_x86_64.whl (429.8 kB view details)

Uploaded CPython 3.13macOS 13.0+ x86-64

docstring_generator_ext-2.0.9-cp313-cp313-macosx_13_0_arm64.whl (433.1 kB view details)

Uploaded CPython 3.13macOS 13.0+ ARM64

File details

Details for the file docstring_generator_ext-2.0.9.tar.gz.

File metadata

  • Download URL: docstring_generator_ext-2.0.9.tar.gz
  • Upload date:
  • Size: 16.6 kB
  • Tags: Source
  • Uploaded using Trusted Publishing? Yes
  • Uploaded via: twine/7.0.0 CPython/3.13.14

File hashes

Hashes for docstring_generator_ext-2.0.9.tar.gz
Algorithm Hash digest
SHA256 e9233e86e7e9798ed30dcf465e7c6d6c05129a86e1b67af25c31be8b918cf1ad
MD5 de8a538ba2020dad33530495b566c7cd
BLAKE2b-256 d075df700a1f13890ae3a9035b41771684ca72a512fe1935ee35d02d4f7200c2

See more details on using hashes here.

Provenance

The following attestation bundles were made for docstring_generator_ext-2.0.9.tar.gz:

Publisher: python-publish-ext.yml on FelixTheC/docstring_generator_ext

Attestations: Values shown here reflect the state when the release was signed and may no longer be current.

File details

Details for the file docstring_generator_ext-2.0.9-cp313-cp313-win_amd64.whl.

File metadata

File hashes

Hashes for docstring_generator_ext-2.0.9-cp313-cp313-win_amd64.whl
Algorithm Hash digest
SHA256 6ce88aa191fb405b9fb93c3e973ca84e1fc06b2a256caea1e525ecaba8aaf988
MD5 3fc59d6803de639c1f231763e5278169
BLAKE2b-256 88b0e22e9a9c651f2f7d163ebdc0e5880642ea866f0ccd45528c02fb706151c4

See more details on using hashes here.

Provenance

The following attestation bundles were made for docstring_generator_ext-2.0.9-cp313-cp313-win_amd64.whl:

Publisher: python-publish-ext.yml on FelixTheC/docstring_generator_ext

Attestations: Values shown here reflect the state when the release was signed and may no longer be current.

File details

Details for the file docstring_generator_ext-2.0.9-cp313-cp313-manylinux_2_27_x86_64.manylinux_2_28_x86_64.whl.

File metadata

File hashes

Hashes for docstring_generator_ext-2.0.9-cp313-cp313-manylinux_2_27_x86_64.manylinux_2_28_x86_64.whl
Algorithm Hash digest
SHA256 5a1c1c61fb476e92a04733056fdebb71eddb3e04e5c0a041cde968f5109e8402
MD5 1ea0334e223bf8d00f72f20d8e7b2b11
BLAKE2b-256 fa2af0625cd363fd5ab6d6883b75833fa09afe919ecad5505fbdf2d8f84d82b4

See more details on using hashes here.

Provenance

The following attestation bundles were made for docstring_generator_ext-2.0.9-cp313-cp313-manylinux_2_27_x86_64.manylinux_2_28_x86_64.whl:

Publisher: python-publish-ext.yml on FelixTheC/docstring_generator_ext

Attestations: Values shown here reflect the state when the release was signed and may no longer be current.

File details

Details for the file docstring_generator_ext-2.0.9-cp313-cp313-macosx_13_0_x86_64.whl.

File metadata

File hashes

Hashes for docstring_generator_ext-2.0.9-cp313-cp313-macosx_13_0_x86_64.whl
Algorithm Hash digest
SHA256 aabb718200c0927067643f7d87c36548cf643de919ae0735bb4afdd6396e6328
MD5 dbdc7b512f02a74c45b6f5bc9e0073e4
BLAKE2b-256 bfc257fa2aee927959294bcaae94ef871fab5fc05363366931238d5f24df0652

See more details on using hashes here.

Provenance

The following attestation bundles were made for docstring_generator_ext-2.0.9-cp313-cp313-macosx_13_0_x86_64.whl:

Publisher: python-publish-ext.yml on FelixTheC/docstring_generator_ext

Attestations: Values shown here reflect the state when the release was signed and may no longer be current.

File details

Details for the file docstring_generator_ext-2.0.9-cp313-cp313-macosx_13_0_arm64.whl.

File metadata

File hashes

Hashes for docstring_generator_ext-2.0.9-cp313-cp313-macosx_13_0_arm64.whl
Algorithm Hash digest
SHA256 83881e391b33d63803f77d9d122bacbe686930a9bebab0aa713da0ceb42e9bb8
MD5 ea2e5e25f01e8cd0b6d947d329a8e2d1
BLAKE2b-256 c190e2c5da74cc48de42cd33ef0606cd24b9f9ce9caed151074e5dfc8e268411

See more details on using hashes here.

Provenance

The following attestation bundles were made for docstring_generator_ext-2.0.9-cp313-cp313-macosx_13_0_arm64.whl:

Publisher: python-publish-ext.yml on FelixTheC/docstring_generator_ext

Attestations: Values shown here reflect the state when the release was signed and may no longer be current.

Release history Release notifications | RSS feed

2.1.0

13 files

2.0.14

13 files

Pre-release

2.0.13a1

13 files

2.0.12

13 files

2.0.11

13 files

2.0.10.post1

13 files

This release

2.0.9 This release

5 files

2.0.8

5 files

2.0.7

5 files

2.0.6

5 files

2.0.5

5 files

2.0.4

5 files

2.0.3

5 files

2.0.2

5 files

Pre-release

2.0.2b0

5 files

2.0.1

5 files

Pre-release

1.0.3a5

5 files

1.0.2

9 files

1.0.1.post2

9 files

0.0.33

1 file

0.0.31

1 file

0.0.28

1 file

0.0.26

2 files

Anthropic, PBC Visionary sponsor Bloomberg Visionary sponsor Hudson River Trading Visionary sponsor Meta Visionary sponsor NVIDIA Visionary sponsor Microsoft Sustainability sponsor Depot Continuous Integration AWS Cloud computing and Security Sponsor Datadog Monitoring Fastly CDN Google Download Analytics Sentry Error logging StatusPage Status page