rebar

rebar is an Erlang build tool that makes it easy to compile and
test Erlang applications, port drivers and releases.

rebar is a self-contained Erlang script, so it's easy to distribute or even
embed directly in a project. Where possible, rebar uses standard Erlang/OTP
conventions for project structures, thus minimizing the amount of build
configuration work. rebar also provides dependency management, enabling
application writers to easily re-use common libraries from a variety of
locations (git, hg, etc).

Building

Information on building and installing Erlang/OTP can be found in the INSTALL.md document.

Dependencies

To build rebar you will need a working installation of Erlang R13B03 (or later).

Should you want to clone the rebar repository, you will also require git.

Downloading

Clone the git repository:

$ git clone git://github.com/basho/rebar.git

Building rebar

$ cd rebar/
$ ./bootstrap
Recompile: src/getopt
...
Recompile: src/rebar_utils
==> rebar (compile)
Congratulations! You now have a self-contained script called "rebar" in
your current working directory. Place this script anywhere in your path
and you can use rebar to build OTP-compliant apps.

Contributing to rebar

Pull requests and branching

Use one topic branch per pull request.

Do not commit to master in your fork.

Provide a clean branch without any merge commits from upstream.

Usually you should collapse (squash) any intermediate commits into the original single commit.

Code style

Do not introduce trailing whitespace.

Do not mix spaces and tabs.

Do not introduce lines longer than 80 characters.

erlang-mode (emacs) indentation is preferred. If you prefer vi, consider extending emacs with Vimpulse.

Writing Commit Messages

Structure your commit message like this:

One line summary (less than 50 characters)

Longer description (wrap at 72 characters)

Summary

• Less than 50 characters
• What was changed
• Imperative present tense (fix, add, change)

Fix bug 123
Add 'foobar' command
Change default timeout to 123

• No period

Description

• Wrap at 72 characters
• Why, explain intention and implementation approach
• Present tense

Atomicity

• Break up logical changes
• Make whitespace changes separately

Dialyzer and Tidier

Before you submit a patch check for discrepancies with Dialyzer:

$ cd rebar/
$ ./bootstrap debug
$ dialyzer ebin -Wunmatched_returns -Werror_handling -Wrace_conditions -Wunderspecs

The following discrepancies are known and safe to ignore:

rebar_templater.erl:249: The call rebar_templater:consult(
                                Cont1::erl_scan:return_cont(),'eof',
                                Acc::[any()])
                         contains an opaque term as 1st argument when terms
                         of different types are expected in these positions
rebar_utils.erl:144: Call to missing or unexported function escript:foldl/3
rebar_utils.erl:165: The created fun has no local return

It is strongly recommended to check the code with Tidier.
Select all transformation options and enable automatic transformation.
If Tidier suggests a transformation apply the changes manually to the source code.
Do not use the code from the tarball (out.tgz) as it will have white-space changes
applied by Erlang's pretty-printer.