FitNesse. SuiteAcceptanceTests. SuiteResponderTests. SuiteEditResponder.
TestLinearFixtureInheritance [add child]

 Set Up: .FitNesse.SuiteAcceptanceTests.SetUp (edit)
 Scenario Libraries
When you edit a test page, FitNesse gathers up the fixtures and places them into the insert fixture menu. The fixtures are found in the !fixture widgets of the test page, and every ancestor of the test page.

They are also found in sibling FixtureList pages but that's a deprecated feature

First create a parent page that has a fixture on it

Action Fixture.
start Page Builder
enter line !fixture parent
enter page ParentPage

Next create a subpage that also has a fixture on it.

Action Fixture.
start Page Builder
enter line !fixture child
enter page ParentPage.TestPage

Now edit the test page.

Response Requester.
uri valid?
ParentPage.TestPage?edit true

Response Examiner.

Finally, let's make sure that the correct fixtures are present.

Response Examiner.
type pattern matches?
contents <option value="parent">parent true
contents <option value="child">child true