Building `git-sizer` from source

Most people can just install a released version of git-sizer, as described in the README.md. However, if you want to test a non-release version, or if you might want to contribute to git-sizer, you can also build it from source.

Build and install using `go get`

Make sure that you have a recent version of the Go language toolchain installed and that you have set GOPATH.
Get git-sizer using go install:
```
go install github.com/github/git-sizer@latest
```
This should install the executable file to $GOPATH/bin/.
Either add $GOPATH/bin to your PATH, or copy the executable file (git-sizer or git-sizer.exe) to a directory that is already in your PATH.

Build using `make`

This procedure is intended for experts and people who want to help develop git-sizer. It should work on Linux or OS X. On other Unix-like systems, this procedure is also likely to work, provided you first install Go manually.

Clone the git-sizer Git repository and switch to that directory:

git clone https://github.com/github/git-sizer.git
cd git-sizer

Install Go if necessary:
```
script/bootstrap
```
(Optional) Run the automated tests:
```
make test
```
Build git-sizer:
```
make
```
If you have a C toolchain set up, you can enable support for isatty() (which turns off --progress by default if output is not to a TTY) by running
```
make USE_ISATTY=true
```
Copy the resulting executable file (bin/git-sizer) to a directory in your PATH.

It is also possible to cross-compile for other platforms that are supported by Go. See the comments in the Makefile for more information.

Making a release

See RELEASING.md.