1 files changed, 57 insertions, 0 deletions
diff --git a/maintainers/scripts/haskell/update-stackage.sh b/maintainers/scripts/haskell/update-stackage.sh
new file mode 100755
index 00000000000..ecf38dc4b90
--- /dev/null
+++ b/maintainers/scripts/haskell/update-stackage.sh
@@ -0,0 +1,57 @@
+#! /usr/bin/env nix-shell
+#! nix-shell -i bash -p nix curl jq nix-prefetch-github git gnused gnugrep -I nixpkgs=.
+
+set -eu -o pipefail
+
+tmpfile=$(mktemp "update-stackage.XXXXXXX")
+# shellcheck disable=SC2064
+
+stackage_config="pkgs/development/haskell-modules/configuration-hackage2nix/stackage.yaml"
+
+trap "rm ${tmpfile} ${tmpfile}.new" 0
+touch "$tmpfile" "$tmpfile.new" # Creating files here so that trap creates no errors.
+
+curl -L -s "https://stackage.org/lts/cabal.config" >"$tmpfile"
+old_version=$(grep "# Stackage" $stackage_config | sed -E 's/.*([0-9]{2}\.[0-9]+)/\1/')
+version=$(sed -rn "s/^--.*http:..(www.)?stackage.org.snapshot.lts-//p" "$tmpfile")
+
+if [[ "$old_version" == "$version" ]]; then
+   echo "No new stackage version"
+   exit 0 # Nothing to do
+fi
+
+echo "Updating Stackage LTS from $old_version to $version."
+
+# Create a simple yaml version of the file.
+sed -r \
+    -e '/^--/d' \
+    -e 's|^constraints:||' \
+    -e 's|^ +|  - |' \
+    -e 's|,$||' \
+    -e '/installed$/d' \
+    -e '/^$/d' \
+    < "${tmpfile}" | sort --ignore-case >"${tmpfile}.new"
+
+cat > $stackage_config << EOF
+# Stackage LTS $version
+# This file is auto-generated by
+# maintainers/scripts/haskell/update-stackage.sh
+default-package-overrides:
+EOF
+
+# Drop restrictions on some tools where we always want the latest version.
+sed -r \
+    -e '/ cabal2nix /d' \
+    -e '/ distribution-nixpkgs /d' \
+    -e '/ jailbreak-cabal /d' \
+    -e '/ language-nix /d' \
+    < "${tmpfile}.new" >> $stackage_config
+
+if [[ "${1:-}" == "--do-commit" ]]; then
+git add $stackage_config
+git commit -F - << EOF
+haskellPackages: stackage-lts $old_version -> $version
+
+This commit has been generated by maintainers/scripts/haskell/update-stackage.sh
+EOF
+fi