Correct usage of `subject` in specs

spec/models/commit_spec.rb

@@ -69,8 +69,9 @@ eos
   end
 
   it_behaves_like 'a mentionable' do
-    let(:subject) { commit }
     let(:mauthor) { create :user, email: commit.author_email }
+    subject { commit }
+
     let(:backref_text) { "commit #{subject.id}" }
     let(:set_mentionable_text) { ->(txt){ subject.stub(safe_message: txt) } }
 

spec/models/issue_spec.rb

@@ -56,7 +56,8 @@ describe Issue do
   end
 
   it_behaves_like 'an editable mentionable' do
-    let(:subject) { create :issue, project: mproject }
+    subject { create(:issue, project: project) }
+
     let(:backref_text) { "issue ##{subject.iid}" }
     let(:set_mentionable_text) { ->(txt){ subject.description = txt } }
   end

spec/models/merge_request_spec.rb

@@ -116,12 +116,13 @@ describe MergeRequest do
   end
 
   it_behaves_like 'an editable mentionable' do
-    let(:subject) { create :merge_request, source_project: mproject, target_project: mproject }
+    subject { create(:merge_request, source_project: project, target_project: project) }
+
     let(:backref_text) { "merge request !#{subject.iid}" }
     let(:set_mentionable_text) { ->(txt){ subject.title = txt } }
   end
 
   it_behaves_like 'a Taskable' do
-    let(:subject) { create :merge_request, :simple }
+    subject { create :merge_request, :simple }
   end
 end

spec/models/note_spec.rb

@@ -629,8 +629,9 @@ describe Note do
   end
 
   it_behaves_like 'an editable mentionable' do
+    subject { create :note, noteable: issue, project: project }
+
     let(:issue) { create :issue, project: project }
-    let(:subject) { create :note, noteable: issue, project: project }
     let(:backref_text) { issue.gfm_reference }
     let(:set_mentionable_text) { ->(txt) { subject.note = txt } }
   end

spec/support/mentionable_shared_examples.rb

 # Specifications for behavior common to all Mentionable implementations.
 # Requires a shared context containing:
-# - let(:subject) { "the mentionable implementation" }
+# - subject { "the mentionable implementation" }
 # - let(:backref_text) { "the way that +subject+ should refer to itself in backreferences " }
 # - let(:set_mentionable_text) { lambda { |txt| "block that assigns txt to the subject's mentionable_text" } }
 

spec/support/taskable_shared_examples.rb

 # Specs for task state functionality for issues and merge requests.
 #
 # Requires a context containing:
-#   let(:subject) { Issue or MergeRequest }
+#   subject { Issue or MergeRequest }
 shared_examples 'a Taskable' do
   before do
     subject.description = <<EOT.gsub(/ {6}/, '')