test #54

	on: push
	name: CI
	jobs:
	diff:
	name: diff
	runs-on: ubuntu-latest

	strategy:
	matrix:
	project:
	- dependencies: 'src.one.cpp\|src.two.cpp'
	path: src/one
	- dependencies: 'src.two.cpp'
	path: src/two
	steps:
	# Prepare project repository.
	- name: Checkout repository
	uses: actions/checkout@v3
	with:
	fetch-depth: 2 # We need to fetch 2 commits to get the diff.

	- name: Check for compilation requirement
	run: \|

	DIFFS=$(git diff --name-only HEAD HEAD~1)
	if echo $DIFFS \| grep -E '${{ matrix.project.dependencies }}'; then
	echo "COMPILATION_FLAG=true" >> $GITHUB_ENV
	echo "COMPILATION_FLAG2=\"true\"" >> $GITHUB_ENV
	echo "COMPILATION_FLAG2=\"false\"" >> $GITHUB_ENV
	else
	echo "COMPILATION_FLAG=false" >> $GITHUB_ENV
	echo "COMPILATION_FLAG3=true" >> $GITHUB_ENV
	echo "COMPILATION_FLAG3=false" >> $GITHUB_ENV
	fi

	echo "${{ env.COMPILATION_FLAG2 }}"
	echo "${{ env.COMPILATION_FLAG3 }}"

	- name: Build Project
	if: ${{ env.COMPILATION_FLAG == 'true' }}
	run: \|
	echo "${{ env.COMPILATION_FLAG2 }}"
	echo "cd ${{ matrix.project.path }}"
	echo "mkdir build"
	echo "cd build"
	echo "cmake .."
	echo "make"

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