[GROOVY-11258] AssertJ collection mapping is badly supported

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 4.0.17
• Fix Version/s: 5.0.0-alpha-11
• Component/s: Static Type Checker

Language

groovy

• Assignee: Eric Milles
• Reporter: Jan Hackel
• Created: 27/Dec/23 08:41
• Updated: 12/Nov/24 11:39
• Resolved: 26/Sep/24 21:09

Description

The following code will fail with the message

[Static type checking] - No such property: x for class: java.lang.Object
 @ line 8, column 13.
         .map{ it.x }
               ^

@groovy.transform.CompileStatic
class AssertJCollectionMappingTest {

  @org.junit.jupiter.api.Test
  void mapping() {
    def texts = somePojos()
    org.assertj.core.api.Assertions.assertThat(texts)
      .map{ it.x }
      .containsExactlyInAnyOrderElementsOf(['a', 'b'])
  }

  private static Collection<Pojo> somePojos() {
    return [new Pojo(x: 'a'), new Pojo(x: 'b')]
  }

  static class Pojo {
    String x
  }
}

Changing the line to

.map({ it.x } as Function<Pojo, String>) 

makes it compile but it is clumsy for more complicated types.

It would be nice if Groovy was able to resolve the types without hints.

Issue Links

• is related to: GROOVY-10153 STC: cannot combine use-variance with bounded polymorphism
• is related to: GROOVY-10651 STC: closure parameter type inference for raw type that is iterable over type parameter
• is related to: GROOVY-10671 STC fails to compile AssertJ fluent API expression
• is related to: GROOVY-10756 STC: parameterized and bounded return value for java class property
• is related to: GROOVY-11204 Incorrect overload selection for subclasses