Add test suite

[paulirish]

• Test suite setup with Bats
• Assertion library courtesy of the very well done bats-assert

Fixtures

I've set up a few fixtures, based on some tricky cases.

# creating a fixture file:
git --no-pager diff .  > fixture.diff
# running it directly:
cat fixture.diff | ./diff-so-fancy

Assertions

The basics look like this:

output=$( load_fixture "ls-function" | $diff_so_fancy )

@test "that it doesnt break" {
  assert_output --partial "diff: "
  refute_output --partial "index 33c3d8b"
}

Between bats and bats-assert there is indended to be support for something like assert_line --index 7 to define specific lines of output`, however I was unable to make that work. I believe its a bug between empty text lines and the escape codes.

CI

This is setup with CircleCI, which works great. The Travis bots are crazy slow for me (though it does work), so I'd prefer being on CircleCI for now.

https://circleci.com/gh/paulirish/diff-so-fancy

Fixes #32

[stevemao]

🎉 Thanks @paulirish , This is so great!
Do I need to enable the hook to make CI work?

[paulirish]

@stevemao no you just need to # with CircleCI and the permissions you grant them will take care of it.

[paulirish]

i'd be a fan of merging this earlier than later. shall we?