[GROOVY-5034] Groovy is producing incorrect generic type signatures for getters that are created by closures

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 1.8.2
• Fix Version/s: 1.8.3, 1.9-beta-4
• Environment: OpenJDK (All Known Versions)
• Assignee: Jochen Theodorou
• Reporter: Graeme Rocher
• Created: 21/Sep/11 10:49
• Updated: 20/Oct/11 04:51
• Resolved: 21/Sep/11 11:20

Description

Example say you have a method like:

    def <T> T  mockController(Class<T> controllerClass) {


        doStuff {
            println controllerClass
            ....
        }
    }

The closure passed to doStuff contains within its byte code a generated getter called "getControllerClass" with the following type signature:

  public Class<T> getControllerClass()
  {
    CallSite[] arrayOfCallSite = $getCallSiteArray();
    return (Class)ScriptBytecodeAdapter.castToType(this.controllerClass.get(), $get$$class$java$lang$Class());
    return null;
  }

The generic type T is not declared anywhere. This causes exceptions on OpenJDK such as:

java.lang.NullPointerException
at com.sun.beans.TypeResolver.resolve(TypeResolver.java:321)
at com.sun.beans.TypeResolver.resolve(TypeResolver.java:351)
at com.sun.beans.TypeResolver.resolve(TypeResolver.java:310)
at com.sun.beans.TypeResolver.resolve(TypeResolver.java:157)
at com.sun.beans.TypeResolver.resolveInClass(TypeResolver.java:78)
at java.beans.FeatureDescriptor.getReturnType(FeatureDescriptor.java:368)
at java.beans.Introspector.getTargetEventInfo(Introspector.java:1020)
at java.beans.Introspector.getBeanInfo(Introspector.java:424)
at java.beans.Introspector.getBeanInfo(Introspector.java:189)
at grails.test.mixin.web.ControllerUnitTestMixin.mockController(ControllerUnitTestMixin.groovy:268)

This issue is the cause of http://jira.grails.org/browse/GRAILS-8031