Fixed web IDE not working for sub-groups

Closes #45412

app/assets/javascripts/ide/ide_router.js

@@ -36,7 +36,7 @@ const router = new VueRouter({
   base: `${gon.relative_url_root}/-/ide/`,
   routes: [
     {
-      path: '/project/:namespace/:project',
+      path: '/project/:namespace/:project*',
       component: EmptyRouterComponent,
       children: [
         {

changelogs/unreleased/ide-subgroup-fix.yml

@@ -0,0 +1,5 @@
+---
+title: Fixed IDE not loading for sub groups
+merge_request:
+author:
+type: fixed

spec/features/ide_spec.rb

@@ -0,0 +1,25 @@
+require 'spec_helper'
+
+describe 'IDE', :js do
+  describe 'sub-groups' do
+    let(:user) { create(:user) }
+    let(:group) { create(:group) }
+    let(:subgroup) { create(:group, parent: group) }
+    let(:subgroup_project) { create(:project, :repository, namespace: subgroup) }
+
+    before do
+      subgroup_project.add_master(user)
+      sign_in(user)
+
+      visit project_path(subgroup_project)
+
+      click_link('Web IDE')
+
+      wait_for_requests
+    end
+
+    it 'loads project in web IDE' do
+      expect(page).to have_selector('.context-header', text: subgroup_project.name)
+    end
+  end
+end