Show diff on failure in cabal-gild check action #79

	name: Check cabal-gild format

	on:
	merge_group:
	pull_request:

	jobs:
	check-cabal-gild:
	runs-on: ubuntu-latest

	env:
	CABAL_GILD_VERSION: "1.3.1.2"

	steps:
	- name: Download cabal-gild
	run: \|
	cabal_gild_path="$(mktemp -d)"
	version="${{env.CABAL_GILD_VERSION}}"
	curl -sL \
	"https://github.com/tfausak/cabal-gild/releases/download/$version/cabal-gild-$version-linux-x64.tar.gz" \
	\| tar -C "$cabal_gild_path" -xz

	echo "PATH=$cabal_gild_path:$PATH" >> "$GITHUB_ENV"

	- uses: actions/checkout@v4

	- name: Run cabal-gild over all modified files
	run: \|
	rc="0"
	echo "cabal-gild version: ${{env.CABAL_GILD_VERSION}}"
	for file in $(git ls-files "*.cabal")
	do
	echo "cabal-gild --mode=check --input=$file"
	if ! cabal-gild --mode=check --input="$file"
	then
	cabal-gild --mode=format --io="$file"
	echo "💣 $file is badly formatted. Fix it with:"
	echo "cabal-gild --mode=format --io=$file"
	echo -e
	echo "Diff for $file:"
	git diff "$file"
	echo -e
	rc="1"
	fi
	done

	exit $rc

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