1 files changed, 1 insertions, 137 deletions
diff --git a/spec/migrations/README.md b/spec/migrations/README.md
index 5df44dbc355..6d396315ded 100644
--- a/spec/migrations/README.md
+++ b/spec/migrations/README.md
@@ -1,137 +1 @@
-# Testing migrations
-
-In order to reliably test a migration, we need to test it against a database
-schema that this migration has been written for. In order to achieve that we
-have some _migration helpers_ and RSpec test tag, called `:migration`.
-
-If you want to write a test for a migration consider adding `:migration` tag to
-the test signature, like `describe SomeMigrationClass, :migration`.
-
-## How does it work?
-
-Adding a `:migration` tag to a test signature injects a few before / after
-hooks to the test.
-
-The most important change is that adding a `:migration` tag adds a `before`
-hook that will revert all migrations to the point that a migration under test
-is not yet migrated.
-
-In other words, our custom RSpec hooks will find a previous migration, and
-migrate the database **down** to the previous migration version.
-
-With this approach you can test a migration against a database schema that this
-migration has been written for.
-
-The `after` hook will migrate the database **up** and reinstitutes the latest
-schema version, so that the process does not affect subsequent specs and
-ensures proper isolation.
-
-## Available helpers
-
-Use `table` helper to create a temporary `ActiveRecord::Base` derived model
-for a table.
-
-See `spec/support/helpers/migrations_helpers.rb` for all the available helpers.
-
-## Testing a class that is an ActiveRecord::Migration
-
-In order to test a class that is an `ActiveRecord::Migration`, you will need to
-manually `require` the migration file because it is not autoloaded with Rails.
-
-Use `migrate!` helper to run the migration that is under test.  It will not only
-run migration, but will also bump the schema version in the `schema_migrations`
-table. It is necessary because in the `after` hook we trigger the rest of
-the migrations, and we need to know where to start.
-
-### Example
-
-This spec tests the [`db/post_migrate/20170526185842_migrate_pipeline_stages.rb`](https://gitlab.com/gitlab-org/gitlab-ce/blob/v11.6.5/db/post_migrate/20170526185842_migrate_pipeline_stages.rb) migration. You can find the complete spec on [`spec/migrations/migrate_pipeline_stages_spec.rb`](https://gitlab.com/gitlab-org/gitlab-ce/blob/v11.6.5/spec/migrations/migrate_pipeline_stages_spec.rb).
-
-```ruby
-require 'spec_helper'
-require Rails.root.join('db', 'post_migrate', '20170526185842_migrate_pipeline_stages.rb')
-
-describe MigratePipelineStages, :migration do
-
-  # Create test data - pipeline and CI/CD jobs.
-
-  let(:jobs) { table(:ci_builds) }
-  let(:stages) { table(:ci_stages) }
-  let(:pipelines) { table(:ci_pipelines) }
-  let(:projects) { table(:projects) }
-
-  before do
-    projects.create!(id: 123, name: 'gitlab1', path: 'gitlab1')
-    pipelines.create!(id: 1, project_id: 123, ref: 'master', sha: 'adf43c3a')
-    jobs.create!(id: 1, commit_id: 1, project_id: 123, stage_idx: 2, stage: 'build')
-    jobs.create!(id: 2, commit_id: 1, project_id: 123, stage_idx: 1, stage: 'test')
-  end
-
-  # Test the migration.
-
-  it 'correctly migrates pipeline stages' do
-    expect(stages.count).to be_zero
-
-    migrate!
-
-    expect(stages.count).to eq 2
-    expect(stages.all.pluck(:name)).to match_array %w[test build]
-  end
-end
-```
-
-## Testing a class that is not an ActiveRecord::Migration
-
-To test a class that is not an `ActiveRecord::Migration` (a background migration),
-you will need to manually provide a required schema version. Please add a
-schema tag to a context that you want to switch the database schema within.
-
-Example: `describe SomeClass, :migration, schema: 20170608152748`.
-
-### Example
-
-This spec tests the [`lib/gitlab/background_migration/archive_legacy_traces.rb`](https://gitlab.com/gitlab-org/gitlab-ce/blob/v11.6.5/lib/gitlab/background_migration/archive_legacy_traces.rb)
-background migration. You can find the complete spec on 
-[`spec/lib/gitlab/background_migration/archive_legacy_traces_spec.rb`](https://gitlab.com/gitlab-org/gitlab-ce/blob/v11.6.5/spec/lib/gitlab/background_migration/archive_legacy_traces_spec.rb)
-
-```ruby
-require 'spec_helper'
-
-describe Gitlab::BackgroundMigration::ArchiveLegacyTraces, :migration, schema: 20180529152628 do
-  include TraceHelpers
-
-  let(:namespaces) { table(:namespaces) }
-  let(:projects) { table(:projects) }
-  let(:builds) { table(:ci_builds) }
-  let(:job_artifacts) { table(:ci_job_artifacts) }
-
-  before do
-    namespaces.create!(id: 123, name: 'gitlab1', path: 'gitlab1')
-    projects.create!(id: 123, name: 'gitlab1', path: 'gitlab1', namespace_id: 123)
-    @build = builds.create!(id: 1, project_id: 123, status: 'success', type: 'Ci::Build')
-  end
-
-  context 'when trace file exsits at the right place' do
-    before do
-      create_legacy_trace(@build, 'trace in file')
-    end
-
-    it 'correctly archive legacy traces' do
-      expect(job_artifacts.count).to eq(0)
-      expect(File.exist?(legacy_trace_path(@build))).to be_truthy
-
-      described_class.new.perform(1, 1)
-
-      expect(job_artifacts.count).to eq(1)
-      expect(File.exist?(legacy_trace_path(@build))).to be_falsy
-      expect(File.read(archived_trace_path(job_artifacts.first))).to eq('trace in file')
-    end
-  end
-end
-```
-
-## Best practices
-
-1. Note that this type of tests do not run within the transaction, we use
-a deletion database cleanup strategy. Do not depend on transaction being
-present.
+Moved to https://docs.gitlab.com/ee/development/testing_migrations_guide.html