[TAP5-2154] Environment keys with empty associated stacks should not be listed as available

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 5.4
• Fix Version/s: 5.4
• Component/s: tapestry-core
• Labels: error-feedback patch test
• Assignee: Howard Lewis Ship
• Reporter: Jochen Kemnade
• Created: 13/Aug/13 10:02
• Updated: 05/Nov/13 00:25
• Resolved: 04/Nov/13 22:41

Description

I just got the confusing error message:

No object of type org.apache.tapestry5.services.Heartbeat is available from the Environment.
Available values:

• org.apache.tapestry5.services.Heartbeat
  ..

That happened because Heartbeat had been pushed and popped during the render cycle. The problem is, that Heartbeat is still a key in the map of available objects, but the list/stack of associated objects is empty.
The patch removes entries removes those keys from the AvailableValues values list.