CI: add linting workflow for recipes

.github/workflows/recipe-checks.yml

@@ -0,0 +1,77 @@
+--- 
+# GitHub workflow to check pull requests and commits for pitfalls and formatting
+# mistakes in build recipes.
+name: Check recipes
+
+'on':
+  workflow_dispatch:
+  push:
+    paths:
+      - '*.sh'
+  pull_request:
+    paths:
+      - '*.sh'
+
+permissions: {}
+
+jobs:
+  lint:
+    name: alidistlint
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Install dependencies
+        run: python3 -m pip install -U --user 'alidistlint[git]'
+
+      - uses: actions/checkout@v6
+        with:
+          fetch-depth: 0
+
+      - name: Run linter
+        run: |
+          if [ -n "$BASE_SHA" ]; then
+            # For pull requests, only check files that have changed relative to
+            # the base commit.
+            merge_base=$(git merge-base "$BASE_SHA" "$HEAD_SHA")
+            git diff -z --diff-filter d --name-only "$merge_base..$HEAD_SHA" -- '*.sh' |
+              xargs -0tr alidistlint -f github --changes "$merge_base..$HEAD_SHA"
+          else
+            # On push, check every file, ignoring warnings and notes.
+            alidistlint -ef github ./*.sh
+          fi
+        env:
+          BASE_SHA: ${{ github.event.pull_request.base.sha }}
+          HEAD_SHA: ${{ github.event.pull_request.head.sha || github.event.head_commit.sha }}
+
+  circular:
+    name: circular dependencies
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Install dependencies
+        run: |
+          sudo apt update -y
+          sudo apt install -y graphviz
+          python3 -m pip install -U --user alibuild
+          aliBuild analytics off
+
+      - uses: actions/checkout@v6
+
+      - name: Run check
+        run: |
+          for fname in *.sh; do
+            case "$fname" in
+              jalien*) default=jalien ;;
+              *) default=o2 ;;
+            esac
+            echo "Checking $fname with --defaults $default"
+            if aliBuild deps --defaults "$default" --outgraph /dev/null --no-system --neat -c . \
+                        "$(awk '/^package: /{print $2}' "$fname")" 2>&1 |
+               grep -q 'transitive reduction not unique'
+            then
+              echo -n "::error title=circular dependency,file=$fname,line=1"
+              echo '::recipe has circular dependency'
+              err=1
+            fi
+          done
+          exit "${err:-0}"