[GROOVY-10756] STC: parameterized and bounded return value for java class property - ASF JIRA

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Given:

A Java class having a method returning a generic Collection,
A groovy script compiled with "CompileStatic" and using the method of the JavaClass

Then the type of the element of the collection is not correctly inferred.

Example:

public class Bridge { // java
    
    public <T extends File> Collection<T> getFiles() {
        return null;
    }
}

and the following script:

@groovy.transform.CompileStatic
def cst() {
    new Bridge().files.collect { it.name }
}

the compilation fails with the error:

[Static type checking] - No such property: name for class: java.lang.Object

Note:

It works in v3.0.10 but not in v3.0.11
It works if the class is defined in the groovy script
A repro is available here: https://github.com/j3rem1e/groovy-bug-generic (>mvn test)

is related to

GROOVY-10153 STC: cannot combine use-variance with bounded polymorphism

GROOVY-10651 STC: closure parameter type inference for raw type that is iterable over type parameter

GROOVY-10671 STC fails to compile AssertJ fluent API expression

relates to

GROOVY-11163 Class parsing does not set erasure of type param with bounds

GROOVY-11258 AssertJ collection mapping is badly supported