.github/workflows/editorconfig.yml: write changed files to disk

This avoids errors when exporting long lists to $GITHUB_ENV.

Co-authored-by: Moritz Hedtke <Moritz.Hedtke@t-online.de>

.github/workflows/editorconfig.yml

@@ -17,30 +17,26 @@ jobs:
       env:
         GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
       run: |
-        echo 'PR_DIFF<<EOF' >> $GITHUB_ENV
         gh api \
           repos/NixOS/nixpkgs/pulls/${{github.event.number}}/files --paginate \
           | jq '.[] | select(.status != "removed") | .filename' \
-          >> $GITHUB_ENV
-        echo 'EOF' >> $GITHUB_ENV
+          > "$HOME/changed_files"
+    - name: print list of changed files
+      run: |
+        cat "$HOME/changed_files"
     - uses: actions/checkout@v2
       with:
         # pull_request_target checks out the base branch by default
         ref: refs/pull/${{ github.event.pull_request.number }}/merge
-      if: env.PR_DIFF
     - uses: cachix/install-nix-action@v16
-      if: env.PR_DIFF
       with:
         # nixpkgs commit is pinned so that it doesn't break
         nix_path: nixpkgs=https://github.com/NixOS/nixpkgs/archive/f93ecc4f6bc60414d8b73dbdf615ceb6a2c604df.tar.gz
     - name: install editorconfig-checker
       run: nix-env -iA editorconfig-checker -f '<nixpkgs>'
-      if: env.PR_DIFF
     - name: Checking EditorConfig
-      if: env.PR_DIFF
       run: |
-        echo "$PR_DIFF" | xargs editorconfig-checker -disable-indent-size
+        cat "$HOME/changed_files" | xargs -r editorconfig-checker -disable-indent-size
     - if: ${{ failure() }}
       run: |
         echo "::error :: Hey! It looks like your changes don't follow our editorconfig settings. Read https://editorconfig.org/#download to configure your editor so you never see this error again."
-