.github/workflows/test.yaml in lrama-0.6.1 vs .github/workflows/test.yaml in lrama-0.6.2

@@ -85,10 +85,15 @@
         with:
           ruby-version: ${{ matrix.ruby }}
           bundler-cache: true
       - run: bundle install
 
+      # Copy from https://github.com/ruby/ruby/blob/cb9a47f2acd6e373ef868b890a9d07da6f565dd4/.github/workflows/check_misc.yml#L31
+      - name: Check if C-sources are US-ASCII
+        run: |
+          grep -r -n --include='*.[chyS]' --include='*.asm' $'[^\t-~]' -- . && exit 1 || :
+
       # Copy from https://github.com/ruby/ruby/blob/089227e94823542acfdafa68541d330eee42ffea/.github/workflows/check_misc.yml#L27
       - name: Check for trailing spaces
         run: |
           git grep -I -n '[	 ]$' -- '*.rb' '*.[chy]' '*.rs' ':!spec/' && exit 1 || :
           git grep -n '^[	 ][	 ]*$' -- '*.md' && exit 1 || :
@@ -118,11 +123,11 @@
     runs-on: ubuntu-20.04
     strategy:
       fail-fast: false
       matrix:
         # '3.0' is the oldest living ruby version
-        # '2.5' is for BASERUBY
-        baseruby: ['head', '3.0', '2.5']
+        # '2.7' is for BASERUBY
+        baseruby: ['head', '3.0', '2.7']
         ruby_branch: ['master']
     defaults:
       run:
         working-directory: ../ruby/build
     steps: