Backport splitting approval changes from CE

Author and committers approvals are split in EE
This commit provides backports for those changes

This reverts commit 886f00bc.

app/models/commit_collection.rb

@@ -20,8 +20,8 @@ class CommitCollection
     commits.each(&block)
   end
 
-  def authors
-    emails = without_merge_commits.map(&:author_email).uniq
+  def committers
+    emails = without_merge_commits.map(&:committer_email).uniq
 
     User.by_any_email(emails)
   end

app/models/merge_request.rb

@@ -323,12 +323,8 @@ class MergeRequest < ApplicationRecord
     work_in_progress?(title) ? title : "WIP: #{title}"
   end
 
-  def commit_authors
-    @commit_authors ||= commits.authors
-  end
-
-  def authors
-    User.from_union([commit_authors, User.where(id: self.author_id)])
+  def committers
+    @committers ||= commits.committers
   end
 
   # Verifies if title has changed not taking into account WIP prefix

spec/models/commit_collection_spec.rb

@@ -14,26 +14,26 @@ describe CommitCollection do
     end
   end
 
-  describe '.authors' do
+  describe '.committers' do
     it 'returns a relation of users when users are found' do
-      user = create(:user, email: commit.author_email.upcase)
+      user = create(:user, email: commit.committer_email.upcase)
       collection = described_class.new(project, [commit])
 
-      expect(collection.authors).to contain_exactly(user)
+      expect(collection.committers).to contain_exactly(user)
     end
 
-    it 'returns empty array when authors cannot be found' do
+    it 'returns empty array when committers cannot be found' do
       collection = described_class.new(project, [commit])
 
-      expect(collection.authors).to be_empty
+      expect(collection.committers).to be_empty
     end
 
     it 'excludes authors of merge commits' do
       commit = project.commit("60ecb67744cb56576c30214ff52294f8ce2def98")
-      create(:user, email: commit.author_email.upcase)
+      create(:user, email: commit.committer_email.upcase)
       collection = described_class.new(project, [commit])
 
-      expect(collection.authors).to be_empty
+      expect(collection.committers).to be_empty
     end
   end
 

spec/models/merge_request_spec.rb

@@ -476,7 +476,6 @@ describe MergeRequest do
       it 'does not cache issues from external trackers' do
         issue  = ExternalIssue.new('JIRA-123', subject.project)
         commit = double('commit1', safe_message: "Fixes #{issue.to_reference}")
-
         allow(subject).to receive(:commits).and_return([commit])
 
         expect { subject.cache_merge_request_closes_issues!(subject.author) }.not_to raise_error
@@ -1065,31 +1064,17 @@ describe MergeRequest do
     end
   end
 
-  describe '#commit_authors' do
-    it 'returns all the authors of every commit in the merge request' do
-      users = subject.commits.without_merge_commits.map(&:author_email).uniq.map do |email|
-        create(:user, email: email)
-      end
-
-      expect(subject.commit_authors).to match_array(users)
-    end
-
-    it 'returns an empty array if no author is associated with a user' do
-      expect(subject.commit_authors).to be_empty
-    end
-  end
-
-  describe '#authors' do
-    it 'returns a list with all the commit authors in the merge request and author' do
-      users = subject.commits.without_merge_commits.map(&:author_email).uniq.map do |email|
+  describe '#committers' do
+    it 'returns all the committers of every commit in the merge request' do
+      users = subject.commits.without_merge_commits.map(&:committer_email).uniq.map do |email|
         create(:user, email: email)
       end
 
-      expect(subject.authors).to match_array([subject.author, *users])
+      expect(subject.committers).to match_array(users)
     end
 
-    it 'returns only the author if no committer is associated with a user' do
-      expect(subject.authors).to contain_exactly(subject.author)
+    it 'returns an empty array if no committer is associated with a user' do
+      expect(subject.committers).to be_empty
     end
   end