[GROOVY-11386] STC: closure property precedence

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 3.0.21, 5.0.0-alpha-8, 4.0.21
• Fix Version/s: 5.0.0-alpha-9
• Component/s: Static Type Checker

Language

groovy

• Assignee: Eric Milles
• Reporter: Eric Milles
• Created: 26/May/24 15:18
• Updated: 12/Nov/24 11:40
• Resolved: 26/May/24 18:52

Description

Properties within a closure are satisfied first against the closure followed by the resolve strategy. This is implemented by: https://github.com/apache/groovy/blob/0e8718d6bafba61daf962892c9d7ae10832b62e0/src/main/java/groovy/lang/Closure.java#L280

The type checker supports this here: https://github.com/apache/groovy/blob/0e8718d6bafba61daf962892c9d7ae10832b62e0/src/main/java/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java#L648

The properties "class" and "metaClass" are missing from the switch. "class" is not possible as a variable. However, "metaClass" is and should refer to the Closure's meta class, not the delegate or owner's meta class. This can be checked by running:

@groovy.transform.TypeChecked
void test(object) {
  object.with {
    print metaClass
  }
}
test("")

This script should print something like "org.codehaus.groovy.runtime.metaclass.ClosureMetaClass@17d2ed1b[class Sample$_test_closure1]".