Scott Murphy Heiberg created GROOVY-12563:
---------------------------------------------
Summary: SC: closures and lambdas in a trait method see the trait
helper class instead of the trait instance
Key: GROOVY-12563
URL: https://issues.apache.org/jira/browse/GROOVY-12563
Project: Groovy
Issue Type: Bug
Components: Static compilation, Static Type Checker
Affects Versions: 5.0.8, 4.0.33, 6.0.0
Reporter: Scott Murphy Heiberg
In a statically compiled trait method, closures and lambdas get the static
helper class where the trait instance (or, in a static method, the implementing
class) is expected:
{code:groovy}
@groovy.transform.CompileStatic
trait T {
String helper() { 'helper' }
Object own() { def c = { owner }; c() }
String viaThis() { def c = { this.helper() }; c() }
String viaLambda() { java.util.function.Supplier<String> s = () ->
helper(); s.get() }
}
@groovy.transform.CompileStatic
class C implements T { }
new C().own() // GroovyCastException: Cannot cast object 'C@...' with
class 'C' to class 'T$Trait$Helper'
new C().viaThis() // ClassCastException: class java.lang.Class cannot be cast
to class T$Trait$Helper
new C().viaLambda() // ClassCastException: class java.lang.Class cannot be cast
to class T
{code}
Also: {{thisObject}}, {{delegate}} without {{@DelegatesTo}}, {{getOwner()}} and
{{getThisObject()}} in such a closure (also under {{@TypeChecked}}); a closure
written in a lambda; {{this.m()}} in a closure of a dynamic or {{@TypeChecked}}
trait (MissingMethodException for a method with arguments, the helper's
{{toString()}} and {{getClass()}}); and calling a static closure field of the
trait as a method:
{code:groovy}
@groovy.transform.CompileStatic
trait T {
static Closure<String> f = { 'f' }
static String callF() { f() }
}
@groovy.transform.CompileStatic
class C implements T { }
C.callF() // 6.0.0: MissingMethodException: No signature of static method:
T__f$get for class: T
// 4.0.33, 5.0.8: [Static type checking] - Cannot find matching
method java.lang.Class#f()
{code}
Expected: these give the values and calls dynamic Groovy gives: the trait
instance as this object, owner and delegate of a closure written directly in a
trait method, the lambda as the owner of a closure written in a lambda, and the
implementing class's static field.
--
This message was sent by Atlassian Jira
(v10.3.26#10030026)
