1 files changed, 34 insertions, 6 deletions
diff --git a/app/models/merge_request.rb b/app/models/merge_request.rb
index 8271dc83116..a015a9ef394 100644
--- a/app/models/merge_request.rb
+++ b/app/models/merge_request.rb
@@ -135,11 +135,8 @@ class MergeRequest < ActiveRecord::Base
   scope :by_branch, ->(branch_name) { where("(source_branch LIKE :branch) OR (target_branch LIKE :branch)", branch: branch_name) }
   scope :cared, ->(user) { where('assignee_id = :user OR author_id = :user', user: user.id) }
   scope :by_milestone, ->(milestone) { where(milestone_id: milestone) }
-  scope :in_projects, ->(project_ids) { where("source_project_id in (:project_ids) OR target_project_id in (:project_ids)", project_ids: project_ids) }
   scope :of_projects, ->(ids) { where(target_project_id: ids) }
-  scope :opened, -> { with_states(:opened, :reopened) }
   scope :merged, -> { with_state(:merged) }
-  scope :closed, -> { with_state(:closed) }
   scope :closed_and_merged, -> { with_states(:closed, :merged) }
 
   scope :join_project, -> { joins(:target_project) }
@@ -163,6 +160,24 @@ class MergeRequest < ActiveRecord::Base
     super("merge_requests", /(?<merge_request>\d+)/)
   end
 
+  # Returns all the merge requests from an ActiveRecord:Relation.
+  #
+  # This method uses a UNION as it usually operates on the result of
+  # ProjectsFinder#execute. PostgreSQL in particular doesn't always like queries
+  # using multiple sub-queries especially when combined with an OR statement.
+  # UNIONs on the other hand perform much better in these cases.
+  #
+  # relation - An ActiveRecord::Relation that returns a list of Projects.
+  #
+  # Returns an ActiveRecord::Relation.
+  def self.in_projects(relation)
+    source = where(source_project_id: relation).select(:id)
+    target = where(target_project_id: relation).select(:id)
+    union  = Gitlab::SQL::Union.new([source, target])
+
+    where("merge_requests.id IN (#{union.to_sql})")
+  end
+
   def to_reference(from_project = nil)
     reference = "#{self.class.reference_prefix}#{iid}"
 
@@ -262,8 +277,14 @@ class MergeRequest < ActiveRecord::Base
     self.target_project.events.where(target_id: self.id, target_type: "MergeRequest", action: Event::CLOSED).last
   end
 
+  WIP_REGEX = /\A\s*(\[WIP\]\s*|WIP:\s*|WIP\s+)+\s*/i.freeze
+
   def work_in_progress?
-    !!(title =~ /\A\[?WIP(\]|:| )/i)
+    title =~ WIP_REGEX
+  end
+
+  def wipless_title
+    self.title.sub(WIP_REGEX, "")
   end
 
   def mergeable?
@@ -501,11 +522,15 @@ class MergeRequest < ActiveRecord::Base
   end
 
   def target_sha
-    @target_sha ||= target_project.repository.commit(target_branch).sha
+    @target_sha ||= target_project.repository.commit(target_branch).try(:sha)
   end
 
   def source_sha
-    last_commit.try(:sha)
+    last_commit.try(:sha) || source_tip.try(:sha)
+  end
+
+  def source_tip
+    source_branch && source_project.repository.commit(source_branch)
   end
 
   def fetch_ref
@@ -553,8 +578,11 @@ class MergeRequest < ActiveRecord::Base
   end
 
   def compute_diverged_commits_count
+    return 0 unless source_sha && target_sha
+
     Gitlab::Git::Commit.between(target_project.repository.raw_repository, source_sha, target_sha).size
   end
+  private :compute_diverged_commits_count
 
   def diverged_from_target_branch?
     diverged_commits_count > 0