false positive: NP_NONNULL_PARAM_VIOLATION on CompletableFuture.getNow(null)

[ylexus]

spotbugs-maven-plugin:3.1.9 reports an error on a valid CompletableFuture.getNow(null) call:

import org.junit.jupiter.api.Test;

import java.util.concurrent.CompletableFuture;
import java.util.concurrent.CompletionException;

import static org.junit.jupiter.api.Assertions.assertThrows;

final class Github1001Test {
    @Test
    void name() {
        CompletableFuture<Object> future = new CompletableFuture<>();
        future.completeExceptionally(new RuntimeException("oops"));
        assertThrows(CompletionException.class, () -> future.getNow(null));
    }
}

[ERROR] Null passed for non-null parameter of java.util.concurrent.CompletableFuture.getNow(Object) in <...> NP_NONNULL_PARAM_VIOLATION

Unrelated, but the suppression (@SuppressFBWarnings("NP_NONNULL_PARAM_VIOLATION")) only works on class level in the example above, probably because the lambda is a static method on this class. Understandable, but very counter-intuitive.

[welcome]

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[ahubold]

Same problem here. This one seems to be similar to #484 and DefaultNullnessAnnotations.java should be extended to allow null values for the getNow() method, similar to the fix for #484 in ac93f80

[b9r5]

Same problem here.