check formatting in ci

.github/workflows/ci.yaml

@@ -10,7 +10,7 @@ jobs:
           sudo apt-get update
           sudo apt-get install -y libcurl4-openssl-dev libsdl1.2-dev libgc-dev libncurses5-dev jq cmake ninja-build clang libfuse2 valgrind libncurses5
       - name: Check out repository code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
         with:
           submodules: recursive
       - name: Set up environment
@@ -26,8 +26,22 @@ jobs:
         run: |
           cat ci-skipped-tests.txt >>skipped-tests.txt
           make STATIC_LLVM=1 test
+          git checkout skipped-tests.txt # Restore for nph
       - name: Run self-compare
         run: make STATIC_LLVM=1 compare
+
+      - name: Check nph formatting
+        # Pin nph to a specific version to avoid sudden style differences.
+        # Updating nph version should be accompanied with running the new
+        # version
+        run: |
+          VERSION="v0.5.1"
+          ARCHIVE="nph-linux_x64.tar.gz"
+          curl -L "https://github.com/arnetheduck/nph/releases/download/${VERSION}/${ARCHIVE}" -o ${ARCHIVE}
+          tar -xzf ${ARCHIVE}
+          git ls-files | grep .nim$ | xargs ./nph
+          git diff --exit-code
+
       - name: Create distribution
         run: bash make-dist.sh
       - name: Update release