Show git error message updating snippet

app/controllers/concerns/snippets_actions.rb

@@ -28,4 +28,11 @@ module SnippetsActions
   def convert_line_endings(content)
     params[:line_ending] == 'raw' ? content : content.gsub(/\r\n/, "\n")
   end
+
+  def check_repository_error
+    repository_error = snippet.errors.delete(:repository)
+
+    flash.now[:alert] = repository_error if repository_error
+    recaptcha_check_with_fallback(repository_error.nil?) { render :edit }
+  end
 end

app/controllers/projects/snippets_controller.rb

@@ -62,7 +62,7 @@ class Projects::SnippetsController < Projects::ApplicationController
     service_response = Snippets::UpdateService.new(project, current_user, update_params).execute(@snippet)
     @snippet = service_response.payload[:snippet]
 
-    recaptcha_check_with_fallback { render :edit }
+    check_repository_error
   end
 
   def show

app/controllers/snippets_controller.rb

@@ -64,7 +64,7 @@ class SnippetsController < ApplicationController
     service_response = Snippets::UpdateService.new(nil, current_user, update_params).execute(@snippet)
     @snippet = service_response.payload[:snippet]
 
-    recaptcha_check_with_fallback { render :edit }
+    check_repository_error
   end
 
   def show

app/services/snippets/update_service.rb

@@ -52,7 +52,7 @@ module Snippets
           create_commit(snippet) if snippet.repository_exists?
         end
       rescue
-        snippet.errors.add(:base, 'Error updating the snippet')
+        snippet.errors.add(:repository, 'Error updating the snippet')
 
         false
       end

changelogs/unreleased/fj-fix-git-error-message-update-snippet.yml

+---
+title: Show git error message updating snippet
+merge_request: 26570
+author:
+type: fixed

spec/features/projects/snippets/user_updates_snippet_spec.rb

@@ -3,9 +3,9 @@
 require 'spec_helper'
 
 describe 'Projects > Snippets > User updates a snippet' do
-  let(:project) { create(:project) }
+  let_it_be(:user) { create(:user) }
+  let_it_be(:project) { create(:project, namespace: user.namespace) }
   let!(:snippet) { create(:project_snippet, project: project, author: user) }
-  let(:user) { create(:user) }
 
   before do
     stub_feature_flags(snippets_vue: false)
@@ -13,16 +13,33 @@ describe 'Projects > Snippets > User updates a snippet' do
     sign_in(user)
 
     visit(project_snippet_path(project, snippet))
-  end
 
-  it 'updates a snippet' do
     page.within('.detail-page-header') do
       first(:link, 'Edit').click
     end
+  end
 
+  it 'updates a snippet' do
     fill_in('project_snippet_title', with: 'Snippet new title')
     click_button('Save')
 
     expect(page).to have_content('Snippet new title')
   end
+
+  context 'when the git operation fails' do
+    before do
+      allow_next_instance_of(Snippets::UpdateService) do |instance|
+        allow(instance).to receive(:create_commit).and_raise(StandardError)
+      end
+
+      fill_in('project_snippet_title', with: 'Snippet new title')
+
+      click_button('Save')
+    end
+
+    it 'renders edit page and displays the error' do
+      expect(page).to have_content('Error updating the snippet')
+      expect(page).to have_content('Edit Snippet')
+    end
+  end
 end

spec/features/snippets/user_edits_snippet_spec.rb

@@ -8,7 +8,7 @@ describe 'User edits snippet', :js do
   let(:file_name) { 'test.rb' }
   let(:content) { 'puts "test"' }
 
-  let(:user) { create(:user) }
+  let_it_be(:user) { create(:user) }
   let(:snippet) { create(:personal_snippet, :public, file_name: file_name, content: content, author: user) }
 
   before do
@@ -58,4 +58,21 @@ describe 'User edits snippet', :js do
     expect(page).to have_no_xpath("//i[@class='fa fa-lock']")
     expect(page).to have_xpath("//i[@class='fa fa-globe']")
   end
+
+  context 'when the git operation fails' do
+    before do
+      allow_next_instance_of(Snippets::UpdateService) do |instance|
+        allow(instance).to receive(:create_commit).and_raise(StandardError)
+      end
+
+      fill_in 'personal_snippet_title', with: 'New Snippet Title'
+
+      click_button('Save changes')
+    end
+
+    it 'renders edit page and displays the error' do
+      expect(page).to have_content('Error updating the snippet')
+      expect(page).to have_content('Edit Snippet')
+    end
+  end
 end

spec/services/snippets/update_service_spec.rb

@@ -148,7 +148,7 @@ describe Snippets::UpdateService do
         response = subject
 
         expect(response).to be_error
-        expect(response.payload[:snippet].errors.full_messages).to eq ['Error updating the snippet']
+        expect(response.payload[:snippet].errors.full_messages).to eq ['Repository Error updating the snippet']
       end
     end
 
@@ -173,7 +173,7 @@ describe Snippets::UpdateService do
         response = subject
 
         expect(response).to be_error
-        expect(response.payload[:snippet].errors.full_messages).to eq ['Error updating the snippet']
+        expect(response.payload[:snippet].errors.full_messages).to eq ['Repository Error updating the snippet']
       end
 
       it 'returns error if snippet does not have a snippet_repository' do