duktape/README.md

Duktape
=======

[![Build status](https://github.com/svaarala/duktape/workflows/Build/badge.svg?branch=master)](https://github.com/svaarala/duktape/actions)
[![Test status](https://github.com/svaarala/duktape/workflows/Test/badge.svg?branch=master)](https://github.com/svaarala/duktape/actions)

:warning: **Master branch is undergoing incompatible changes for Duktape 3.x**.
To track Duktape 2.x, follow the `v2-maintenance` branch.

Introduction
------------

[Duktape](http://duktape.org/) is an **embeddable Javascript** engine,
with a focus on **portability** and **compact** footprint.

Duktape is easy to integrate into a C/C++ project: add `duktape.c`,
`duktape.h`, and `duk_config.h` to your build, and use the Duktape API
to call ECMAScript functions from C code and vice versa.

Main features:

* Embeddable, portable, compact
* ECMAScript E5/E5.1 compliant, with some semantics updated from ES2015+
* Partial support for ECMAScript 2015 (E6) and ECMAScript 2016 (E7),
  [Post-ES5 feature status](http://wiki.duktape.org/PostEs5Features.html),
  [kangax/compat-table](https://kangax.github.io/compat-table)
* ES2015 TypedArray and Node.js Buffer bindings
* WHATWG Encoding API living standard
* Built-in debugger
* Built-in regular expression engine
* Built-in Unicode support
* Minimal platform dependencies
* Combined reference counting and mark-and-sweep garbage collection with finalization
* Custom features like coroutines
* Property virtualization using a subset of ECMAScript ES2015 Proxy object
* Bytecode dump/load for caching compiled functions
* Distributable includes an optional logging framework, CommonJS-based module
  loading implementations, CBOR bindings, etc
* Liberal MIT license (see LICENSE.txt)

See [duktape.org](http://duktape.org/) for packaged end-user downloads
and documentation.  The end user downloads are also available from the
[duktape-releases](https://github.com/svaarala/duktape-releases) repo
as both binaries and in unpacked form as git tags.

Have fun!

Support
-------

* Duktape Wiki: [wiki.duktape.org](http://wiki.duktape.org)
* User community Q&A: Stack Overflow [duktape](http://stackoverflow.com/questions/tagged/duktape) tag
* Bugs and feature requests: [GitHub issues](https://github.com/svaarala/duktape/issues)
* General discussion: IRC `#duktape` on `chat.freenode.net` ([webchat](https://webchat.freenode.net))

About this repository
---------------------

This repository is **intended for Duktape developers only**, and contains
Duktape internals: test cases, internal documentation, sources for the
duktape.org web site, etc.

Getting started: end user
-------------------------

When embedding Duktape in your application you should use the packaged source
distributables available from [duktape.org/download.html](http://duktape.org/download.html).
See [duktape.org/guide.html#gettingstarted](http://duktape.org/guide.html#gettingstarted)
for the basics.

The distributable `src/` directory contains a `duk_config.h` configuration
header and amalgamated sources for Duktape default configuration.  If
necessary, use `python tools/configure.py` to create header and sources for
customized configuration options, see http://wiki.duktape.org/Configuring.html.
For example, to enable fastint support (example for Linux):

    $ tar xvfJ duktape-2.0.0.tar.xz
    $ cd duktape-2.0.0
    $ rm -rf src-custom
    $ python tools/configure.py \
          --source-directory src-input \
          --output-directory src-custom \
          --config-metadata config \
          -DDUK_USE_FASTINT

    # src-custom/ will now contain: duktape.c, duktape.h, duk_config.h.

You can download and install Duktape using the
[vcpkg](https://github.com/Microsoft/vcpkg) dependency manager:
   
    $ git clone https://github.com/Microsoft/vcpkg.git
    $ cd vcpkg
    $ ./bootstrap-vcpkg.sh
    $ ./vcpkg integrate install
    $ vcpkg install duktape
    
The Duktape port in vcpkg is kept up to date by Microsoft team members
and community contributors.  If the version is out of date, please
[create an issue or pull request](https://github.com/Microsoft/vcpkg) on
the vcpkg repository.

You can also clone this repository, make modifications, and build a source
distributable on Linux, macOS, and Windows using `python util/dist.py`.
You'll need Python 2 and Python YAML binding.

Getting started: modifying and rebuilding the distributable
-----------------------------------------------------------

If you intend to change Duktape internals and want to rebuild the source
distributable in Linux, macOS, or Windows:

    # Linux; can often install from packages or using 'pip'
    # Install Node.js >= 16.x
    $ sudo apt-get install python python-yaml
    $ python util/dist.py

    # macOS
    # Install Python 2.7.x
    # Install Node.js >= 16.x
    $ pip install PyYAML
    $ python util/dist.py

    # Windows
    ; Install Python 2.7.x from python.org, and add it to PATH
    ; Install Node.js >= 16.x
    > pip install PyYAML
    > python util\dist.py

The source distributable directory will be in `dist/`.

For platform specific notes see http://wiki.duktape.org/DevelopmentSetup.html.

Getting started: other development (Linux only)
-----------------------------------------------

Other development stuff, such as building the website and running test cases,
is based on a `Makefile` **supported for Linux x86-64 only**.

There are some Docker images which can simplify the development setup and also
document the needed packages.  These are also **supported for Linux x86-64 only**.
For example:

    # Build Docker images.  This takes a long time.
    $ make docker-images

    # Equivalent of 'make dist-source', but runs inside a container.
    $ make docker-dist-source-wd

    # Run a shell with /work/duktape containing a disposable master snapshot.
    $ make docker-shell-master

    # Run a shell with /work/duktape mounted from current directory.
    # This allows editing, building, testing, etc with an interactive
    # shell running in the container.
    $ make docker-shell-wdmount

    # For non-native images you may need:
    # https://github.com/multiarch/qemu-user-static

There is limited support for developing on macOS via Docker.  On Apple M1:

    $ make docker-images-arm64
    $ DOCKER_ARCH=arm64 make docker-shell-wdmount

Branch policy
-------------

* The `master` branch is used for active development.  Even though pull requests
  are tested before merging, master may still be broken from time to time.  When
  development on a new major release starts, master will also get API
  incompatible changes without warning.  For these reasons **you should
  generally not depend on the master branch** for building your project; use
  a release tag (e.g. `v2.4.0`) or a release maintenance branch
  (e.g. `v2.4-maintenance` or `v2-maintenance`) instead.

* Pull requests and their related branches are frequently rebased so you
  should not fork off them.  Pull requests may be open for a while for
  testing and discussion.

* Release tags like `v1.4.1` are used for releases and match the released
  distributables.  These are stable once the release is complete.

* Maintenance branches are used for backporting fixes and features for
  maintenance releases.  Documentation changes go to master for maintenance
  releases too.  For example, `v1.5-maintenance` was created for the 1.5.0
  release and is used for 1.5.x maintenance releases.

* A maintenance branch is also created for a major release when master moves
  on to active development of the next major release.  For example,
  `v1-maintenance` was created when 1.5.0 was released (last planned 1.x
  release) and development of 2.0.0 (with API incompatible changes) started
  on master.  The 1.6.0 and 1.7.0 releases were made from `v1-maintenance`
  for example.

Versioning
----------

Duktape uses [Semantic Versioning](http://semver.org/) for official
releases.  Builds from Duktape repo are not official releases and don't
follow strict semver, mainly because `DUK_VERSION` needs to have some
compromise value that won't be strictly semver conforming.
Because Duktape tracks the latest ECMAScript specification versions,
compliance fixes are made in minor versions even when they are technically
not backwards compatible.  See
[Versioning](http://duktape.org/guide.html#versioning) for details.

Reporting bugs
--------------

See [CONTRIBUTING.md](https://github.com/svaarala/duktape/blob/master/CONTRIBUTING.md).

Security critical GitHub issues (for example anything leading to a segfault)
are tagged `security`.

Contributing
------------

See [CONTRIBUTING.md](https://github.com/svaarala/duktape/blob/master/CONTRIBUTING.md).

Copyright and license
---------------------

See [AUTHORS.rst](https://github.com/svaarala/duktape/blob/master/AUTHORS.rst)
and [LICENSE.txt](https://github.com/svaarala/duktape/blob/master/LICENSE.txt).

[Duktape Wiki](https://github.com/svaarala/duktape-wiki/) is part of Duktape
documentation and under the same copyright and license.