Add latest changes from gitlab-org/gitlab@master

3 files changed, 50 insertions, 2 deletions

diff --git a/doc/development/changelog.md b/doc/development/changelog.md
index 8ded3f393ee..af2c540cca5 100644
--- a/doc/development/changelog.md
+++ b/doc/development/changelog.md
@@ -41,7 +41,10 @@ the `author` field. GitLab team members **should not**.
   a changelog entry regardless of these guidelines if the contributor wants one.
   Example: "Fixed a typo on the search results page."
 - Any docs-only changes **should not** have a changelog entry.
-- Any change behind a feature flag **should not** have a changelog entry. The entry should be added [in the merge request removing the feature flags](feature_flags/development.md).
+- Any change behind a feature flag **should not** have a changelog entry. The
+  entry should be added [in the merge request removing the feature flags](feature_flags/development.md).
+  If the change includes a database migration, there should be a changelog entry
+  for the migration change.
 - A fix for a regression introduced and then fixed in the same release (i.e.,
   fixing a bug introduced during a monthly release candidate) **should not**
   have a changelog entry.
diff --git a/doc/development/feature_flags/development.md b/doc/development/feature_flags/development.md
index 929c9b1c71c..de8098434c2 100644
--- a/doc/development/feature_flags/development.md
+++ b/doc/development/feature_flags/development.md
@@ -25,7 +25,8 @@ end
 
 Features that are developed and are intended to be merged behind a feature flag
 should not include a changelog entry. The entry should be added in the merge
-request removing the feature flags.
+request removing the feature flag. If the feature contains any DB migration it
+should include a changelog entry for DB changes.
 
 In the rare case that you need the feature flag to be on automatically, use
 `default_enabled: true` when checking:
diff --git a/doc/development/testing_guide/frontend_testing.md b/doc/development/testing_guide/frontend_testing.md
index 314995ca9b3..d0669c5ebd4 100644
--- a/doc/development/testing_guide/frontend_testing.md
+++ b/doc/development/testing_guide/frontend_testing.md
@@ -119,6 +119,50 @@ Global mocks introduce magic and can affect how modules are imported in your tes
 
 When in doubt, construct mocks in your test file using [`jest.mock()`](https://jestjs.io/docs/en/jest-object#jestmockmodulename-factory-options), [`jest.spyOn()`](https://jestjs.io/docs/en/jest-object#jestspyonobject-methodname), etc.
 
+### Data-driven tests
+
+Similar to [RSpec's parameterized tests](best_practices.md#table-based--parameterized-tests),
+Jest supports data-driven tests for:
+
+- Individual tests using [`test.each`](https://jestjs.io/docs/en/api#testeachtable-name-fn-timeout) (aliased to `it.each`).
+- Groups of tests using [`describe.each`](https://jestjs.io/docs/en/api#describeeachtable-name-fn-timeout).
+
+These can be useful for reducing repetition within tests. Each option can take an array of
+data values or a tagged template literal.
+
+For example:
+
+```javascript
+// function to test
+const icon = status => status ? 'pipeline-passed' : 'pipeline-failed'
+const message = status => status ? 'pipeline-passed' : 'pipeline-failed'
+
+// test with array block
+it.each([
+    [false, 'pipeline-failed'],
+    [true, 'pipeline-passed']
+])('icon with %s will return %s',
+ (status, icon) => {
+    expect(renderPipeline(status)).toEqual(icon)
+ }
+);
+
+// test suite with tagged template literal block
+describe.each`
+    status   | icon                 | message
+    ${false} | ${'pipeline-failed'} | ${'Pipeline failed - boo-urns'}
+    ${true}  | ${'pipeline-passed'} | ${'Pipeline succeeded - win!'}
+`('pipeline component', ({ status, icon, message }) => {
+    it(`returns icon ${icon} with status ${status}`, () => {
+        expect(icon(status)).toEqual(message)
+    })
+
+    it(`returns message ${message} with status ${status}`, () => {
+        expect(message(status)).toEqual(message)
+    })
+});
+```
+
 ## Karma test suite
 
 GitLab uses the [Karma][karma] test runner with [Jasmine] as its test