Merge pull request #1102 from cesc1989/subjectstub-examples

Add clearer examples for SubjectStub cop

docs/modules/ROOT/pages/cops_rspec.adoc

@@ -3822,11 +3822,21 @@ Checks for stubbed test subjects.
 [source,ruby]
 ----
 # bad
-describe Foo do
-  subject(:bar) { baz }
+describe Article do
+  subject(:article) { Article.new }
 
-  before do
-    allow(bar).to receive(:qux?).and_return(true)
+  it 'indicates that the author is unknown' do
+    allow(article).to receive(:author).and_return(nil)
+    expect(article.description).to include('by an unknown author')
+  end
+end
+
+# good
+describe Article do
+  subject(:article) { Article.new(author: nil) }
+
+  it 'indicates that the author is unknown' do
+    expect(article.description).to include('by an unknown author')
   end
 end
 ----

lib/rubocop/cop/rspec/subject_stub.rb

@@ -13,11 +13,21 @@ module RSpec
       #
       # @example
       #   # bad
-      #   describe Foo do
-      #     subject(:bar) { baz }
+      #   describe Article do
+      #     subject(:article) { Article.new }
       #
-      #     before do
-      #       allow(bar).to receive(:qux?).and_return(true)
+      #     it 'indicates that the author is unknown' do
+      #       allow(article).to receive(:author).and_return(nil)
+      #       expect(article.description).to include('by an unknown author')
+      #     end
+      #   end
+      #
+      #   # good
+      #   describe Article do
+      #     subject(:article) { Article.new(author: nil) }
+      #
+      #     it 'indicates that the author is unknown' do
+      #       expect(article.description).to include('by an unknown author')
       #     end
       #   end
       #