Merge branch 'dm-outdated-diff-link' into 'master'

Link to outdated diff in older MR version from outdated diff discussion

Closes #27865

See merge request !10572

10 files changed, 57 insertions, 21 deletions

diff --git a/app/models/concerns/discussion_on_diff.rb b/app/models/concerns/discussion_on_diff.rb
index 87db0c810c3..67b1cace3eb 100644
--- a/app/models/concerns/discussion_on_diff.rb
+++ b/app/models/concerns/discussion_on_diff.rb
@@ -5,8 +5,6 @@ module DiscussionOnDiff
   included do
     NUMBER_OF_TRUNCATED_DIFF_LINES = 16
 
-    memoized_values << :active
-
     delegate  :line_code,
               :original_line_code,
               :diff_file,
@@ -29,12 +27,6 @@ module DiscussionOnDiff
     true
   end
 
-  def active?
-    return @active if @active.present?
-
-    @active = first_note.active?
-  end
-
   # Returns an array of at most 16 highlighted lines above a diff note
   def truncated_diff_lines(highlight: true)
     lines = highlight ? highlighted_diff_lines : diff_lines
diff --git a/app/models/concerns/note_on_diff.rb b/app/models/concerns/note_on_diff.rb
index 1a5a7007a2b..6c27dd5aa5c 100644
--- a/app/models/concerns/note_on_diff.rb
+++ b/app/models/concerns/note_on_diff.rb
@@ -25,4 +25,18 @@ module NoteOnDiff
   def diff_attributes
     raise NotImplementedError
   end
+
+  def active?(diff_refs = nil)
+    raise NotImplementedError
+  end
+
+  private
+
+  def noteable_diff_refs
+    if noteable.respond_to?(:diff_sha_refs)
+      noteable.diff_sha_refs
+    else
+      noteable.diff_refs
+    end
+  end
 end
diff --git a/app/models/concerns/noteable.rb b/app/models/concerns/noteable.rb
index 772ff6a6d2f..dd1e6630642 100644
--- a/app/models/concerns/noteable.rb
+++ b/app/models/concerns/noteable.rb
@@ -36,10 +36,10 @@ module Noteable
       .discussions(self)
   end
 
-  def grouped_diff_discussions
+  def grouped_diff_discussions(*args)
     # Doesn't use `discussion_notes`, because this may include commit diff notes
     # besides MR diff notes, that we do no want to display on the MR Changes tab.
-    notes.inc_relations_for_view.grouped_diff_discussions
+    notes.inc_relations_for_view.grouped_diff_discussions(*args)
   end
 
   def resolvable_discussions
diff --git a/app/models/diff_discussion.rb b/app/models/diff_discussion.rb
index d9b7e484e0f..6a6466b493b 100644
--- a/app/models/diff_discussion.rb
+++ b/app/models/diff_discussion.rb
@@ -10,6 +10,7 @@ class DiffDiscussion < Discussion
 
   delegate  :position,
             :original_position,
+            :latest_merge_request_diff,
 
             to: :first_note
 
diff --git a/app/models/diff_note.rb b/app/models/diff_note.rb
index 1523244f8a8..abe4518d62a 100644
--- a/app/models/diff_note.rb
+++ b/app/models/diff_note.rb
@@ -65,20 +65,18 @@ class DiffNote < Note
     self.position.diff_refs == diff_refs
   end
 
+  def latest_merge_request_diff
+    return unless for_merge_request?
+
+    self.noteable.merge_request_diff_for(self.position.diff_refs)
+  end
+
   private
 
   def supported?
     for_commit? || self.noteable.has_complete_diff_refs?
   end
 
-  def noteable_diff_refs
-    if noteable.respond_to?(:diff_sha_refs)
-      noteable.diff_sha_refs
-    else
-      noteable.diff_refs
-    end
-  end
-
   def set_original_position
     self.original_position = self.position.dup unless self.original_position&.complete?
   end
diff --git a/app/models/legacy_diff_discussion.rb b/app/models/legacy_diff_discussion.rb
index cb2651a03f8..e617ce36f56 100644
--- a/app/models/legacy_diff_discussion.rb
+++ b/app/models/legacy_diff_discussion.rb
@@ -7,6 +7,8 @@
 class LegacyDiffDiscussion < Discussion
   include DiscussionOnDiff
 
+  memoized_values << :active
+
   def legacy_diff_discussion?
     true
   end
@@ -15,6 +17,12 @@ class LegacyDiffDiscussion < Discussion
     LegacyDiffNote
   end
 
+  def active?(*args)
+    return @active if @active.present?
+
+    @active = first_note.active?(*args)
+  end
+
   def collapsed?
     !active?
   end
diff --git a/app/models/legacy_diff_note.rb b/app/models/legacy_diff_note.rb
index 9a77557ebcd..d7c627432d2 100644
--- a/app/models/legacy_diff_note.rb
+++ b/app/models/legacy_diff_note.rb
@@ -56,11 +56,12 @@ class LegacyDiffNote < Note
   #
   # If the note's current diff cannot be matched in the MergeRequest's current
   # diff, it's considered inactive.
-  def active?
+  def active?(diff_refs = nil)
     return @active if defined?(@active)
     return true if for_commit?
     return true unless diff_line
     return false unless noteable
+    return false if diff_refs && diff_refs != noteable_diff_refs
 
     noteable_diff = find_noteable_diff
 
diff --git a/app/models/merge_request.rb b/app/models/merge_request.rb
index d02fa308b9f..1d4827375d7 100644
--- a/app/models/merge_request.rb
+++ b/app/models/merge_request.rb
@@ -366,6 +366,14 @@ class MergeRequest < ActiveRecord::Base
     merge_request_diff(true)
   end
 
+  def merge_request_diff_for(diff_refs)
+    @merge_request_diffs_by_diff_refs ||= Hash.new do |h, diff_refs|
+      h[diff_refs] = merge_request_diffs.viewable.select_without_diff.find_by_diff_refs(diff_refs)
+    end
+
+    @merge_request_diffs_by_diff_refs[diff_refs]
+  end
+
   def reload_diff_if_branch_changed
     if source_branch_changed? || target_branch_changed?
       reload_diff
diff --git a/app/models/merge_request_diff.rb b/app/models/merge_request_diff.rb
index 6ad56b842b2..6604af2b47e 100644
--- a/app/models/merge_request_diff.rb
+++ b/app/models/merge_request_diff.rb
@@ -31,6 +31,10 @@ class MergeRequestDiff < ActiveRecord::Base
   # It allows you to override variables like head_commit_sha before getting diff.
   after_create :save_git_content, unless: :importing?
 
+  def self.find_by_diff_refs(diff_refs)
+    find_by(start_commit_sha: diff_refs.start_sha, head_commit_sha: diff_refs.head_sha, base_commit_sha: diff_refs.base_sha)
+  end
+
   def self.select_without_diff
     select(column_names - ['st_diffs'])
   end
@@ -130,6 +134,12 @@ class MergeRequestDiff < ActiveRecord::Base
     st_commits.map { |commit| commit[:id] }
   end
 
+  def diff_refs=(new_diff_refs)
+    self.base_commit_sha = new_diff_refs&.base_sha
+    self.start_commit_sha = new_diff_refs&.start_sha
+    self.head_commit_sha = new_diff_refs&.head_sha
+  end
+
   def diff_refs
     return unless start_commit_sha || base_commit_sha
 
diff --git a/app/models/note.rb b/app/models/note.rb
index 1ea7b946061..c85692c5aec 100644
--- a/app/models/note.rb
+++ b/app/models/note.rb
@@ -113,11 +113,11 @@ class Note < ActiveRecord::Base
       Discussion.build(notes)
     end
 
-    def grouped_diff_discussions
+    def grouped_diff_discussions(diff_refs = nil)
       diff_notes.
         fresh.
         discussions.
-        select(&:active?).
+        select { |n| n.active?(diff_refs) }.
         group_by(&:line_code)
     end
 
@@ -140,6 +140,10 @@ class Note < ActiveRecord::Base
     true
   end
 
+  def latest_merge_request_diff
+    nil
+  end
+
   def max_attachment_size
     current_application_settings.max_attachment_size.megabytes.to_i
   end