Run specs in CI with/without the engine

Author: zlw

.github/workflows/ci.yml

@@ -28,12 +28,16 @@ jobs:
         - "3.0"
         - "2.7"
         - "2.6"
+        dummy:
+        - "with-engine"
+        - "without-engine"
         include:
           - ruby: "3.0"
             coverage: "true"
     env:
       COVERAGE: ${{matrix.coverage}}
       COVERAGE_TOKEN: ${{secrets.CODACY_PROJECT_TOKEN}}
+      TEST_DUMMY: ${{matrix.dummy}}
     steps:
       - name: Checkout
         uses: actions/checkout@v1

spec/spec_helper.rb

@@ -15,8 +15,8 @@
 ENV["RAILS_ENV"] ||= "test"
 
 RAILS_VERSION = ENV["RAILS_VERSION"] || "6.x"
-WITH_ENGINE = (ENV["WITH_ENGINE"] || "true") == "true"
-DUMMY_DIR = WITH_ENGINE ? "with-engine" : "without-engine"
+DUMMY_DIR     = ENV["TEST_DUMMY"] || 'with-engine'
+WITH_ENGINE   = DUMMY_DIR == 'with-engine'
 require SPEC_ROOT.join("dummies/#{DUMMY_DIR}/dummy-#{RAILS_VERSION}/dummy/config/environment").to_s
 
 require "rspec/rails"