[GROOVY-7190] Problem With Static Fields Defined In A Trait

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.3.8
• Fix Version/s: 2.3.9, 2.4.0-rc-1
• Assignee: Cédric Champeau
• Reporter: Jeff Brown
• Created: 02/Dec/14 18:44
• Updated: 23/Dec/14 19:45
• Resolved: 05/Dec/14 07:08

Description

A problem occurs when a static method defined in a trait attempts to retrieve the value of a static field without using "this". Note that assigning a value to the static field appears to work but retrieving the value does not.

The attached app contains the following code.

src/demo/SomeTrait.groovy

package demo

trait SomeTrait {
    private static String someString

    static String getStringValue() {
        if(someString == null) {
            someString = 'Default Value'
        }
        someString
    }

    static String getStringValueUsingThis() {
        if(this.someString == null) {
            someString = 'Default Value'
        }
        this.someString
    }
}

src/demo/SomeClass.groovy

package demo

class SomeClass implements SomeTrait {}

test/demo/SomeClassTest.groovy

package demo

class SomeClassTest extends GroovyTestCase {

    void testStaticPropertyAccess() {
        // this fails
        assert 'Default Value' == SomeClass.stringValue
    }

    void testStaticPropertyAccessUsingThis() {
        // this passes
        assert 'Default Value' == SomeClass.stringValueUsingThis
    }
}

The test fails with the following:

groovy.lang.MissingMethodException: No signature of method: java.lang.Class.demo_SomeTrait__someString$get() is applicable for argument types: () values: []
	at org.codehaus.groovy.runtime.ScriptBytecodeAdapter.unwrap(ScriptBytecodeAdapter.java:56)
	at org.codehaus.groovy.runtime.callsite.StaticMetaClassSite.call(StaticMetaClassSite.java:52)
	at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:45)
	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:108)
	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:112)
	at demo.SomeTrait$Trait$Helper.getStringValue(SomeTrait.groovy:7)
	at demo.SomeTrait$Trait$Helper$getStringValue$0.call(Unknown Source)
	at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:45)
	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:108)
	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:116)
	at demo.SomeClass.getStringValue(SomeClass.groovy)