[TAP5-1621] TypeCoercer currently uses Object -> String and String -> Boolean, there should be a direct coercion from Object -> Boolean for <t:if/> performance.

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 5.3
• Fix Version/s: 5.3
• Component/s: tapestry-core
• Assignee: Josh Canfield
• Reporter: Josh Canfield
• Created: 26/Aug/11 16:42
• Updated: 10/Sep/11 18:34
• Resolved: 09/Sep/11 16:51

Description

An issue was raised in this thread:
http://tapestry.1045711.n5.nabble.com/Null-check-property-expression-syntax-td4726386.html

Describing the problem where:

<t:if test="MyObject">

causes MyObject to be coerced to a String before being coerced to a Boolean. For some objects this may be an expensive operation, and the common case (how often is the Entity you are editing on a page actually null?)

Adding an explicit Object -> Boolean coercion will remove the need for the Object -> String coercion.

A Number -> Boolean coercion is also required to prevent Integer -> Boolean from choosing the Object -> Boolean as a match (currently it goes Integer -> Long -> Boolean)

At this point the only known issue is that any POJO that depends on the fact that returning "false" from toString will cause the Object -> String -> Boolean to return false will be broken. This seems like an unlikely case and can be worked around by providing a specific TypeCoercion for that object.