Tips for contributors
---------------------

* Please **make pull requests against `master`**.
* Please add a **test case** under `test/regress` when possible.
* If you're making **changes to files for which the CI build is not
  relevant**, please **add `[ci skip]` to the end of the commit message**.
* Report bugs using [GitHub Issues].

GLOSSARY
----

Developing the Ledger software uses a number different tools, not all of
which will be familiar to all developers.

**[Boost]**: a standard set of C++ libraries.  Most
Boost libraries consist of inline functions and templates in header files.

**[Boost.Python]**:  C++ library which enables seamless interoperability
between C++ and the Python programming language.

**[CMake]**: A cross platform system for building from source code.  It uses
the `CMakeLists.txt` files.

**[Doxygen]**: generates programming documentation from
source code files.  Primarily used on C++ sources, but works on all.  Uses
the `doc/Doxyfile.in` file.

**[GCC]**: Gnu Compiler Collection, which includes the
*gcc* compiler and *gcov* coverage/profiler tool.

**[clang]**: C language family frontend for LLVM, which
includes the *clang* compiler.

**[GMP]**: Gnu Multiple Precision Arithmetic Library
provides arbitrary precision math.

**[MPFR]**: Gnu Multiple Precision Floating-point Library
with correct rounding.

**[Markdown]**: A typesetter
format that produces *html* files from *.md* files.  Note that GitHub
automatically renders *.md* files.

**[SHA1]**: a marginally secure cryptographic hash function, used only for
signing the license file.

**[Texinfo]**: Gnu documentation
typesetter that produces *html* and *pdf* files from the `doc/\*.texi` files.

**[GitHub Actions]**: a hosted continuous integration
  service that builds and runs tests each commit posted to GitHub.  Each
  build creates a log, updates a [small badge] at
  the top left of the main project's
  [README.md], and
  emails the author of the commit if any tests fail.

**[utfcpp]**: a library for handling utf-8 in a variety of C++ versions.


Orientation
---

The source tree can be confusing to a new developer.  Here is a selective
orientation:

**./acprep**: a custom thousand-line script to install dependencies, grab
  updates, and build.  It also creates `\*.cmake`,
  `./CmakeFiles/` and other CMake temporary files.  Use `./acprep --help`
  for more information.

**./README.md**: user readme file in markdown format, also used as the project
  description on GitHub.

**./contrib/**: contributed scripts of random quality and completion.  They
  usually require editing to run.

**./doc/**: documentation, licenses, and
  tools for generating documents such as the *pdf* manual.

**./lib/**: a couple of libraries used in development.

**./python/**:  samples using the Python ledger module.

**./src/**:  the C++ header and source files in a flat directory.

**./test/**:  a testing harness with subdirectories full of tests

**./tools/**:  an accretion of tools, mostly small scripts, to aid development


Building
---

If you are going to be working on Ledger, you'll want to enable both debug
builds (which are the default, using `acprep`), and also the use of
pre-compiled headers.  To do this, specify your compiler as either `clang++`
or `g++` as follows:

    mkdir build
    ./acprep --compiler=clang++
    cd build
    make

This will set up a debug build using clang++ (and pre-compiled headers, which
is enabled by the combination of those two), and then start a build.

For even quicker rebuilds, try the Ninja build tool, which is very fast at
determining what to rebuild, and automatically takes advantage of multiple
cores:

    mkdir build
    ./acprep --compiler=clang++ --ninja
    cd build
    ninja

[Boost]: http://boost.org
[Boost.Python]: http://www.boost.org/libs/python/
[GitHub Issues]: https://github.com/ledger/ledger/issues
[GMP]: http://gmplib.org/
[MPFR]: http://www.mpfr.org/
[CMake]: http://www.cmake.org
[Doxygen]: http://doxygen.org
[Markdown]: https://daringfireball.net/projects/markdown/
[SHA1]: http://en.wikipedia.org/wiki/SHA-1
[Texinfo]: http://www.gnu.org/software/texinfo/
[GitHub Actions]: https://github.com/features/actions
[GCC]: http://gcc.gnu.org
[utfcpp]: http://utfcpp.sourceforge.net
[small badge]: https://github.com/ledger/ledger/actions/workflows/cmake.yml/badge.svg
[git-flow]: http://nvie.com/posts/a-successful-git-branching-model/
[README.md]: https://github.com/ledger/ledger/blob/master/README.md
[clang]: http://clang.llvm.org