Add check for poetry version

action.yml

@@ -67,13 +67,26 @@ runs:
         $poetry_ config virtualenvs.in-project ${{ inputs.virtualenvs-in-project }}
         $poetry_ config virtualenvs.path ${{ inputs.virtualenvs-path }}
 
-        # Install plugins from whitespace or commas-delimited list
+        # Parse plugins from whitespace or commas-delimited list
         plugins=(`echo "${{ inputs.plugins }}" | tr ',' ' '`)
-        for plugin in "${plugins[@]}"
-        do
-            echo "Installing plugin: $plugin"
-            $poetry_ plugin add $plugin
-        done 
+        if [ ${#plugins[@]} -gt 0 ]; then
+
+          # Ensure poetry version >= 1.2
+          version=${{ inputs.version }}
+          major=${version:0:1}
+          minor=${version:2:1}
+          if [ $major -lt 1 ] || [ $minor -lt 2 ]; then
+            echo "Use of plugins requires Poetry version >= 1.2"
+            exit 1
+          fi
+
+          # Install plugins
+          for plugin in "${plugins[@]}"
+          do
+              echo "Installing plugin: $plugin"
+              $poetry_ plugin add $plugin
+          done
+        fi
 
         config="$($poetry_ config --list)"