[GROOVY-7269] Problem With MetaMethods and replacing MetaProperty

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.3.9, 2.4.0
• Fix Version/s: 2.3.10, 2.4.1
• Assignee: Cédric Champeau
• Reporter: Jeff Brown
• Created: 23/Jan/15 09:52
• Updated: 23/Feb/15 01:12
• Resolved: 13/Feb/15 04:26

Description

The attached readonlyproperty.zip contains the following:

src/main/groovy/demo/SomeTrait.groovy

package demo

trait SomeTrait {
    String title
}

src/test/groovy/demo/SomeTraitSpec.groovy

package demo

import spock.lang.Specification

class SomeTraitSpec extends Specification {

    void 'test property access'() {
        given:
        Widget.metaClass.getTitle = {
            'Some Default Title'
        }
        def w = new Widget()

        when:
        w.title = 'Some New Title'

        then:
        w.title == 'Some Default Title'
    }
}

class Widget implements SomeTrait {}

That test will fail with the following:

groovy.lang.ReadOnlyPropertyException: Cannot set readonly property: title for class: demo.Widget
    at demo.SomeTraitSpec.test property access(SomeTraitSpec.groovy:15)

If the trait is removed from the equation and the title property is declared directly in the Widget class then the test passes.

Issue Links

• is related to: GROOVY-7308 Change In MetaClass Behavior