Improvements to testing tooling #3

	name: Run Tests
	on:
	pull_request:
	branches:
	- dev
	concurrency:
	group: '${{ github.workflow }}-${{ github.ref }}'
	cancel-in-progress: true
	jobs:
	run_build_diff:
	if: github.repository == 'PathOfBuildingCommunity/PathOfBuilding'
	runs-on: ubuntu-latest
	steps:
	- name: Checkout HEAD
	uses: actions/checkout@v4
	- name: Fetch Dev branch
	run: git fetch --depth=1
	- name: Get Dev branch HEAD hash
	id: get-dev-ref
	run: echo "devref=$(git rev-parse origin/dev)" >> $GITHUB_OUTPUT
	- name: Create cache folder
	run: mkdir /tmp/cache/
	- name: Check if build cache exists
	uses: actions/cache@v4
	with:
	path: /tmp/cache/
	key: '${{ steps.get-dev-ref.outputs.devref }}'
	- name: Make sure cache is readable by docker
	run: chmod -R 777 /tmp/cache
	- name: Run build diff
	run: docker compose run -v '/tmp/cache/:/cache' -e 'CACHEDIR=/cache' busted-diff \| tee /tmp/dockerlog
	- name: Generate artefact
	run: \|
	sed -n '/Savefile Diff for/, $p' /tmp/dockerlog \| tee /tmp/artefact
	[ -s /tmp/artefact ] \|\| rm /tmp/artefact
	- name: Upload artefact
	uses: actions/upload-artifact@v4
	with:
	name: build-diff-output
	path: /tmp/artefact

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