Add spec for todo with target_type Commit

changelogs/unreleased/22951-fix-todos-api-endpoint-error-for-commits.yml

+---
+title: Add spec for todo with target_type Commit
+merge_request: 9351
+author: George Andrinopoulos

lib/api/entities.rb

@@ -397,11 +397,8 @@ module API
       expose :target_type
 
       expose :target do |todo, options|
-        if todo.target_type == 'Commit'
-          Entities.const_get('RepoCommit').represent(todo.target, options)
-        else
-          Entities.const_get(todo.target_type).represent(todo.target, options)
-        end
+        target = todo.target_type == 'Commit' ? 'RepoCommit' : todo.target_type
+        Entities.const_get(target).represent(todo.target, options)
       end
 
       expose :target_url do |todo, options|

spec/factories/todos.rb

@@ -44,4 +44,13 @@ FactoryGirl.define do
       state :done
     end
   end
+
+  factory :on_commit_todo, class: Todo do
+    project factory: :empty_project
+    author
+    user
+    action { Todo::ASSIGNED }
+    commit_id RepoHelpers.sample_commit.id
+    target_type "Commit"
+  end
 end

spec/requests/api/todos_spec.rb

@@ -3,7 +3,7 @@ require 'spec_helper'
 describe API::Todos, api: true do
   include ApiHelpers
 
-  let(:project_1) { create(:empty_project) }
+  let(:project_1) { create(:empty_project, :test_repo) }
   let(:project_2) { create(:empty_project) }
   let(:author_1) { create(:user) }
   let(:author_2) { create(:user) }
@@ -11,7 +11,7 @@ describe API::Todos, api: true do
   let(:merge_request) { create(:merge_request, source_project: project_1) }
   let!(:pending_1) { create(:todo, :mentioned, project: project_1, author: author_1, user: john_doe) }
   let!(:pending_2) { create(:todo, project: project_2, author: author_2, user: john_doe) }
-  let!(:pending_3) { create(:todo, project: project_1, author: author_2, user: john_doe) }
+  let!(:pending_3) { create(:on_commit_todo, project: project_1, author: author_2, user: john_doe) }
   let!(:done) { create(:todo, :done, project: project_1, author: author_1, user: john_doe) }
 
   before do