Allow resolving conflicts in MR controller

2 files changed, 63 insertions, 1 deletions

diff --git a/lib/gitlab/conflict/file.rb b/lib/gitlab/conflict/file.rb
index 7f81c72431d..80f6f7feecf 100644
--- a/lib/gitlab/conflict/file.rb
+++ b/lib/gitlab/conflict/file.rb
@@ -1,6 +1,9 @@
 module Gitlab
   module Conflict
     class File
+      class MissingResolution < StandardError
+      end
+
       CONTEXT_LINES = 3
 
       attr_reader :merge_file_result, :their_path, :their_ref, :our_path, :our_ref, :repository
@@ -21,6 +24,39 @@ module Gitlab
                                                       their_path: their_path)
       end
 
+      def resolve!(resolution, index:, rugged:)
+        new_file = resolve_lines(resolution).map(&:text).join("\n")
+
+        oid = rugged.write(new_file, :blob)
+        our_mode = index.conflict_get(our_path)[:ours][:mode]
+        index.add(path: our_path, oid: oid, mode: our_mode)
+        index.conflict_remove(our_path)
+      end
+
+      def resolve_lines(resolution)
+        current_section = nil
+
+        lines.map do |line|
+          unless line.type
+            current_section = nil
+            next line
+          end
+
+          current_section ||= resolution[line_code(line)]
+
+          case current_section
+          when 'ours'
+            next unless line.type == 'new'
+          when 'theirs'
+            next unless line.type == 'old'
+          else
+            raise MissingResolution
+          end
+
+          line
+        end.compact
+      end
+
       def highlighted_lines
         return @highlighted_lines if @highlighted_lines
 
@@ -77,10 +113,16 @@ module Gitlab
             match_line.text = "@@ -#{match_line.old_pos},#{lines.last.old_pos} +#{match_line.new_pos},#{lines.last.new_pos} @@"
           end
 
-          section || { conflict: !no_conflict, lines: lines }
+          section ||= { conflict: !no_conflict, lines: lines }
+          section[:id] = line_code(lines.first) unless no_conflict
+          section
         end
       end
 
+      def line_code(line)
+        Gitlab::Diff::LineCode.generate(our_path, line.new_pos, line.old_pos)
+      end
+
       def as_json(opts = nil)
         {
           old_path: their_path,
diff --git a/lib/gitlab/conflict/file_collection.rb b/lib/gitlab/conflict/file_collection.rb
index a3035a5c3e6..a4a1505bb7d 100644
--- a/lib/gitlab/conflict/file_collection.rb
+++ b/lib/gitlab/conflict/file_collection.rb
@@ -17,6 +17,26 @@ module Gitlab
         @merge_index ||= repository.rugged.merge_commits(our_commit, their_commit)
       end
 
+      def resolve_conflicts!(resolutions, commit_message, user:)
+        rugged = repository.rugged
+        committer = repository.user_to_committer(user)
+        commit_message ||= default_commit_message
+
+        files.each do |file|
+          file.resolve!(resolutions, index: merge_index, rugged: rugged)
+        end
+
+        new_tree = merge_index.write_tree(rugged)
+
+        Rugged::Commit.create(rugged,
+                              author: committer,
+                              committer: committer,
+                              tree: new_tree,
+                              message: commit_message,
+                              parents: [our_commit, their_commit],
+                              update_ref: Gitlab::Git::BRANCH_REF_PREFIX + merge_request.source_branch)
+      end
+
       def files
         @files ||= merge_index.conflicts.map do |conflict|
           their_path = conflict[:theirs][:path]