Don't provide system spec generator under Rails 5.1

Author: benoittgt

lib/generators/rspec/system/system_generator.rb

@@ -1,24 +1,25 @@
 require 'generators/rspec'
 
-module Rspec
-  module Generators
-    # @private
-    class SystemGenerator < Base
-      class_option :system_specs, :type => :boolean, :default => true,  :desc => "Generate system specs"
+if ::Rails::VERSION::STRING >= '5.1'
+  module Rspec
+    module Generators
+      # @private
+      class SystemGenerator < Base
+        class_option :system_specs, :type => :boolean, :default => true,  :desc => "Generate system specs"
 
-      def generate_system_spec
-        return unless options[:system_specs]
-        raise "System Tests are available for Rails >= 5.1" if ::Rails::VERSION::STRING < '5.1'
+        def generate_system_spec
+          return unless options[:system_specs]
 
-        template template_name, File.join('spec/system', class_path, filename)
-      end
+          template template_name, File.join('spec/system', class_path, filename)
+        end
 
-      def template_name
-        'system_spec.rb'
-      end
+        def template_name
+          'system_spec.rb'
+        end
 
-      def filename
-        "#{table_name}_spec.rb"
+        def filename
+          "#{table_name}_spec.rb"
+        end
       end
     end
   end

spec/generators/rspec/system/system_generator_spec.rb

@@ -7,39 +7,30 @@
 
   describe "system specs" do
     subject(:system_spec) { file("spec/system/posts_spec.rb") }
-    if ::Rails::VERSION::STRING < '5.1'
-      describe "are not available" do
-        it "raise error for user" do
-          expect{ run_generator(%w(posts)) }
-            .to raise_error(RuntimeError, "System Tests are available for Rails >= 5.1")
-        end
+    describe "are generated independently from the command line" do
+      before do
+        run_generator %w(posts)
       end
-    else
-      describe "are generated independently from the command line" do
-        before do
-          run_generator %w(posts)
+      describe "the spec" do
+        it "exists" do
+          expect(system_spec).to exist
+        end
+        it "contains 'rails_helper'" do
+          expect(system_spec).to contain(/require 'rails_helper'/)
         end
-        describe "the spec" do
-          it "exists" do
-            expect(system_spec).to exist
-          end
-          it "contains 'rails_helper'" do
-            expect(system_spec).to contain(/require 'rails_helper'/)
-          end
-          it "contains the system" do
-            expect(system_spec).to contain(/^RSpec.describe \"Posts\", #{type_metatag(:system)}/)
-          end
+        it "contains the system" do
+          expect(system_spec).to contain(/^RSpec.describe \"Posts\", #{type_metatag(:system)}/)
         end
       end
+    end
 
-      describe "are not generated" do
-        before do
-          run_generator %w(posts --no-system-specs)
-        end
-        describe "the spec" do
-          it "does not exist" do
-            expect(system_spec).to_not exist
-          end
+    describe "are not generated" do
+      before do
+        run_generator %w(posts --no-system-specs)
+      end
+      describe "the spec" do
+        it "does not exist" do
+          expect(system_spec).to_not exist
         end
       end
     end