[Backport release-24.11] workflows/lint: run all the static lints in same workflow

.github/workflows/lint.yml

@@ -0,0 +1,101 @@
+name: Lint
+
+on:
+  pull_request:
+    paths:
+      - .github/workflows/lint.yml
+  pull_request_target:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event_name }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+permissions: {}
+
+defaults:
+  run:
+    shell: bash
+
+jobs:
+  treefmt:
+    runs-on: ubuntu-24.04-arm
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          sparse-checkout: .github/actions
+      - name: Check if the PR can be merged and checkout the merge commit
+        uses: ./.github/actions/get-merge-commit
+        with:
+          merged-as-untrusted: true
+
+      - uses: cachix/install-nix-action@17fe5fb4a23ad6cbbe47d6b3f359611ad276644c # v31
+        with:
+          extra_nix_config: sandbox = true
+
+      - name: Check that files are formatted
+        run: |
+          # Note that it's fine to run this on untrusted code because:
+          # - There's no secrets accessible here
+          # - The build is sandboxed
+          if ! nix-build untrusted/ci -A fmt.check; then
+            echo "Some files are not properly formatted"
+            echo "Please format them by going to the Nixpkgs root directory and running one of:"
+            echo "  nix-shell --run treefmt"
+            echo "  nix develop --command treefmt"
+            echo "  nix fmt"
+            echo "Make sure your branch is up to date with master; rebase if not."
+            echo "If you're having trouble, please ping @NixOS/nix-formatting"
+            exit 1
+          fi
+
+  parse:
+    runs-on: ubuntu-24.04-arm
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          sparse-checkout: .github/actions
+      - name: Check if the PR can be merged and checkout the merge commit
+        uses: ./.github/actions/get-merge-commit
+        with:
+          merged-as-untrusted: true
+
+      - uses: cachix/install-nix-action@526118121621777ccd86f79b04685a9319637641 # v31
+        with:
+          extra_nix_config: sandbox = true
+
+      - name: Parse all nix files
+        run: |
+          # Tests multiple versions at once, let's make sure all of them run, so keep-going.
+          nix-build untrusted/ci -A parse --keep-going
+
+  nixpkgs-vet:
+    runs-on: ubuntu-24.04-arm
+    # This should take 1 minute at most, but let's be generous. The default of 6 hours is definitely too long.
+    timeout-minutes: 10
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          sparse-checkout: .github/actions
+      - name: Check if the PR can be merged and checkout merged and target commits
+        uses: ./.github/actions/get-merge-commit
+        with:
+          merged-as-untrusted: true
+          target-as-trusted: true
+
+      - uses: cachix/install-nix-action@526118121621777ccd86f79b04685a9319637641 # v31
+        with:
+          extra_nix_config: sandbox = true
+
+      - name: Running nixpkgs-vet
+        env:
+          # Force terminal colors to be enabled. The library that `nixpkgs-vet` uses respects https://bixense.com/clicolors/
+          CLICOLOR_FORCE: 1
+        run: |
+          if nix-build untrusted/ci -A nixpkgs-vet --arg base "./trusted" --arg head "./untrusted"; then
+            exit 0
+          else
+            exitCode=$?
+            echo "To run locally: ./ci/nixpkgs-vet.sh $GITHUB_BASE_REF https://github.com/$GITHUB_REPOSITORY.git"
+            echo "If you're having trouble, ping @NixOS/nixpkgs-vet"
+            exit "$exitCode"
+          fi