Fix nil edge condition for initial commit diff preview. #80

	name: Elixir CI

	on:
	push:
	branches: [ master ]
	pull_request:
	branches: [ master ]

	jobs:
	build:

	name: Build and test
	runs-on: ubuntu-latest

	services:
	db:
	image: postgres:11
	ports: ['5432:5432']
	env:
	POSTGRES_PASSWORD: postgres
	options: >-
	--health-cmd pg_isready
	--health-interval 10s
	--health-timeout 5s
	--health-retries 5

	steps:
	- uses: actions/checkout@v2
	- name: Set up Elixir
	uses: actions/setup-elixir@v1
	with:
	elixir-version: '1.12.1'
	otp-version: '24.0'
	experimental-otp: true
	- name: Install libgit2
	run: sudo apt-get install libgit2-dev
	- name: Generate SSH public keys
	run: \|
	mkdir apps/gitgud/priv/ssh-keys
	ssh-keygen -m PEM -t rsa -f apps/gitgud/priv/ssh-keys/ssh_host_rsa_key
	- name: Restore dependencies cache
	uses: actions/cache@v2
	with:
	path: deps
	key: ${{ runner.os }}-mix-${{ hashFiles('**/mix.lock') }}
	restore-keys: ${{ runner.os }}-mix-
	- name: Install dependencies
	run: mix deps.get
	- name: Run tests
	run: mix test

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