Issues with Groovy 5 and with

[jochenberger]

Hi,

I found some odd behavior when migrating one of my projects to Groovy 5. I'm not sure whether it's to be expected. It seems to have something to do with how properties are resolved inside closures.

@Grab(group='org.spockframework', module='spock-core', version='2.4-M7-groovy-5.0')
import spock.lang.*

class TestSpec extends Specification {

  static Locale DE = Locale.GERMAN

  def "foo"(){
    given:
    Map m = ['de': 'foo']
    expect:
    m.(DE) == 'foo'
    
    with(m){
      it.(Locale.GERMAN) == 'foo' // works
      it.(this.DE) == 'foo' // works
      it.(DE) == 'foo' // fails
    }
  }
}

The output is

JUnit5 launcher: passed=0, aborted=0, failed=1, skipped=0, time=11ms

Failures (1):
  Spock:TestSpec:foo
    MethodSource [className = 'TestSpec', methodName = 'foo', methodParameterTypes = '']
    => Condition failed with Exception:

it.(DE) == 'foo'
|  |
|  java.lang.NullPointerException: Cannot invoke "String.isEmpty()" because "name" is null
|  	at TestSpec.foo_closure1(test-groovy-5.groovy:17)
|  	at spock.lang.Specification.with(Specification.java:206)
|  	at TestSpec.foo(test-groovy-5.groovy:14)
[de:foo]

       TestSpec.foo_closure1(test-groovy-5.groovy:17)
       spock.lang.Specification.with(Specification.java:206)
       TestSpec.foo(test-groovy-5.groovy:14)
     Caused by: java.lang.NullPointerException: Cannot invoke "String.isEmpty()" because "name" is null
       [...]

With the Groovy 4 module, the test passes.

Can someone please help me understand what's going on here?

[jochenberger]

Oh, this is interesting:

@Grab(group='org.spockframework', module='spock-core', version='2.4-M7-groovy-5.0')
import spock.lang.*

class TestSpec extends Specification {

  static Locale DE = Locale.GERMAN

  def "foo"(){
    expect:
    DE == Locale.GERMAN

    with(''){
      DE == Locale.GERMAN // works
    }
    
    with([DE:Locale.GERMAN]){
      DE == Locale.GERMAN // works
    }
    
    with([:]){
      DE == Locale.GERMAN // fails with Groovy 5 but works with 4.
    }
  }
}

So, if the with context is a Map, it seems to try to resolve DE inside it when using Groovy 5.

[jochenberger]

Yes, it seems to have changed in Groovy 5.

class Test {

  static foo = 'bar'
  
  def run(){
    [:].with {
      println foo
    }
  }
}

new Test().run()

That prints 'bar' in Groovy 4 and 'null' in Groovy 5.

[Vampire]

Yes, you are fully right.
This resolution logic around static fields and precedence against a map delegate in a closure changed in Groovy 5.
Before Groovy 5 static field references were written as direct field reads,
Groovy 5 uses the normal getProperty Groovy logic for those, which means that in your case it gets the map entry for that key which is null.