FasterXML / FasterXML/java-classmate

Unintuitive information about member methods wrt return type covariance

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Dominant language
Java
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Description

I've recently come across a surprising behaviour regarding `MemberResolver`'s `getMemberMethods`. Consider the following classes:

```java
interface Foo {}

class Bar implements Foo {}

interface A {
Foo doSomething();
}

class B {
public Bar doSomething() {
return null;
}
}

class C extends B implements A {}
```

Notice that `C` implements `A.doSomething()` through `B.doSomething()`.

When inspecting the members of C like this:

```java
var typeResolver = new TypeResolver();
var methods = new MemberResolver(typeResolver).resolve(typeResolver.resolve(C.class), null, null).getMemberMethods();
```

`methods` will contain a single method - `public abstract Foo A.doSomething()`. However, this doesn't tell the whole story - notice that `B.doSomething` actually returns a `Bar` instead of a `Foo`. Therefore, in this case I'd expect `methods` to contain `public Bar B.doSomething()`, which gives me more information than `A.doSomething()` does.

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