[GROOVY-9151] Default Arguments: reference to another defaulted parameter causes run-time errors

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.0-beta-2, 2.5.16
• Assignee: Eric Milles
• Reporter: Eric Milles
• Created: 29/May/19 22:47
• Updated: 22/Feb/22 23:57
• Resolved: 29/Jun/19 16:10

Description

Default argument values may be supplied using back references, like this:

void hello(String s, Object o = s) { println o }
hello('world')

or this:

void hello(String s, Object o = new String(s)) { println o }
hello('world')

 

However, if the back reference s also has a default value, Groovy produces nasty errors:

void hello(String s = 'world', Object o = new String(s)) { println o }
hello() // MissingPropertyException: No such property: s for class: script

or worse:

class Thing {
  Thing(String s = 'boo', Object o = new String(s)) {
  }
}
new Thing()

Exception in thread "main" java.lang.VerifyError: Bad type on operand stack
Exception Details:
  Location:
    Thing.<init>()V @21: invokeinterface
  Reason:
    Type uninitializedThis (current frame, stack[5]) is not assignable to 'java/lang/Object'
  Current Frame:
    bci: @21
    flags: { flagThisUninit }
    locals: { uninitializedThis, '[Lorg/codehaus/groovy/runtime/callsite/CallSite;' }
    stack: { uninitializedThis, 'java/lang/String', 'org/codehaus/groovy/runtime/callsite/CallSite', 'java/lang/Class', 'org/codehaus/groovy/runtime/callsite/CallSite', uninitializedThis }
  Bytecode:
    0x0000000: b800 154c 2a12 31c0 0027 2b12 3232 1227
    0x0000010: 2b12 3332 2ab9 0037 0200 b900 2d03 00b7
    0x0000020: 002f b1                                

	at java.lang.Class.getDeclaredConstructors0(Native Method)
	at java.lang.Class.privateGetDeclaredConstructors(Class.java:2671)
	at java.lang.Class.getDeclaredConstructors(Class.java:2020)
	at org.codehaus.groovy.reflection.CachedClass$2$1.run(CachedClass.java:84)
	at java.security.AccessController.doPrivileged(Native Method)
	at org.codehaus.groovy.reflection.CachedClass$2.initValue(CachedClass.java:82)
	at org.codehaus.groovy.reflection.CachedClass$2.initValue(CachedClass.java:79)
	at org.codehaus.groovy.util.LazyReference.getLocked(LazyReference.java:49)
	at org.codehaus.groovy.util.LazyReference.get(LazyReference.java:36)
	at org.codehaus.groovy.reflection.CachedClass.getConstructors(CachedClass.java:295)
	at groovy.lang.MetaClassImpl.<init>(MetaClassImpl.java:232)
	at groovy.lang.MetaClassImpl.<init>(MetaClassImpl.java:242)
	at groovy.lang.MetaClassRegistry$MetaClassCreationHandle.createNormalMetaClass(MetaClassRegistry.java:171)
	at groovy.lang.MetaClassRegistry$MetaClassCreationHandle.createWithCustomLookup(MetaClassRegistry.java:161)
	at groovy.lang.MetaClassRegistry$MetaClassCreationHandle.create(MetaClassRegistry.java:144)
	at org.codehaus.groovy.reflection.ClassInfo.getMetaClassUnderLock(ClassInfo.java:288)
	at org.codehaus.groovy.reflection.ClassInfo.getMetaClass(ClassInfo.java:331)
	at org.codehaus.groovy.runtime.metaclass.MetaClassRegistryImpl.getMetaClass(MetaClassRegistryImpl.java:277)
	at org.codehaus.groovy.runtime.InvokerHelper.getMetaClass(InvokerHelper.java:905)
	at org.codehaus.groovy.runtime.callsite.CallSiteArray.createCallConstructorSite(CallSiteArray.java:86)
	at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCallConstructor(CallSiteArray.java:59)
	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callConstructor(AbstractCallSite.java:238)
	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callConstructor(AbstractCallSite.java:242)
	at script.run(script.groovy:5)

Issue Links

• links to: GitHub Pull Request #949