1 files changed, 39 insertions, 0 deletions
diff --git a/spec/tasks/gitlab/db/decomposition/migrate_rake_spec.rb b/spec/tasks/gitlab/db/decomposition/migrate_rake_spec.rb
new file mode 100644
index 00000000000..300c7009154
--- /dev/null
+++ b/spec/tasks/gitlab/db/decomposition/migrate_rake_spec.rb
@@ -0,0 +1,39 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe 'gitlab:db:decomposition:migrate', feature_category: :cell do
+  before(:all) do
+    skip_if_database_exists(:ci)
+
+    Rake.application.rake_require 'tasks/gitlab/db/decomposition/migrate'
+  end
+
+  subject(:migrate_task) { run_rake_task('gitlab:db:decomposition:migrate') }
+
+  before do
+    allow_next_instance_of(Gitlab::Database::Decomposition::Migrate) do |instance|
+      allow(instance).to receive(:process!)
+    end
+  end
+
+  it 'calls Gitlab::Database::Decomposition::Migrate#process!' do
+    expect_next_instance_of(Gitlab::Database::Decomposition::Migrate) do |instance|
+      expect(instance).to receive(:process!)
+    end
+
+    migrate_task
+  end
+
+  context 'when a Gitlab::Database::Decomposition::Migrate::Error is raised' do
+    before do
+      allow_next_instance_of(Gitlab::Database::Decomposition::Migrate) do |instance|
+        allow(instance).to receive(:process!).and_raise(Gitlab::Database::Decomposition::MigrateError, 'some error')
+      end
+    end
+
+    it 'renders error' do
+      expect { migrate_task }.to output("some error\n").to_stdout.and raise_error(SystemExit)
+    end
+  end
+end