Automatic release scripts and workflow (#386)

Author: filipeom

.github/workflows/publish.yml

@@ -0,0 +1,30 @@
+name: opam-repository
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  publish:
+    runs-on: ubuntu-latest
+    env:
+      # allow opam depext to yes package manager prompts
+      OPAMCONFIRMLEVEL: unsafe-yes
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v5
+        with:
+          fetch-depth: 0
+          tags: true
+
+      - name: Setup OCaml
+        uses: ocaml/setup-ocaml@v3
+        with:
+          ocaml-compiler: "5.3"
+
+      - name: Install dependencies
+        run: opam install opam-publish
+
+      - name: Publish
+        run: ./scripts/publish.sh

scripts/create-release.sh

@@ -0,0 +1,28 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+TAG="$1"
+BRANCH="release/v$TAG"
+
+if ! command -v git-cliff >/dev/null; then
+  echo "git-cliff is not installed. Run: cargo install git-cliff"
+  exit 1
+fi
+
+# Fail fast if opam-publish isn't installed
+if ! command -v gh >/dev/null; then
+  echo "github-clie is not installed."
+  exit 1
+fi
+
+git switch -c $BRANCH
+git-cliff -c cliff.toml -t $TAG -o CHANGES.md
+git add CHANGES.md
+git commit -m "Release $TAG"
+git push -u origin $BRANCH
+
+gh pr create \
+  --base "main" \
+  --head "$BRANCH" \
+  --title "Release $TAG" \
+  --body "Automated Release $TAG"

scripts/publish.sh

@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+TAG="$(git describe --tags --exact-match 2>/dev/null || true)"
+
+if [ -z "$TAG" ]; then
+  echo "No tag on the current commit. Nothing to release."
+  exit 0
+fi
+
+echo "Found tag $TAG on HEAD. Releasing…"
+
+# Remove pin depends which are not allowed in opam-repository
+sed -i '/^pin-depends:/,$d' smtml.opam
+
+opam exec -- opam-publish \
+  --tag="$TAG" \
+  --no-confirmation \
+  --no-browser