IntelliJ outputs error messages twice

I am working on IntelliJ 2019.3, with Truth 1.0 and Java 11.0.6, and running tests using Junit 5.6.0.

I’m trying to do test some basic assertions, such as checking the value of an int. However, IntelliJ is printing the messages twice:

@Test
@Tag("D")
public void testDuplicateDemo() {
    int x = 5;
    assertThat(x).isEqualTo(10);
}

Outputs:

This is rather annoying and unexpected behavior. If I test equality of Strings, the same behavior is shown, unless the string has multiple lines, in which case, only expected / but was appears.

Why is this happening? Is there a workaround / fix? Thanks!

[cpovirk]

There may be drawbacks to this that I’m not thinking of, but…

I would love to see this changed on the IntelliJ side. If the ComparisonFailure or AssertionFailedError has a message, I would like to see IntelliJ skip displaying its own “Expected” and “Actual” (though keep its “<Click to see difference>”).

In the case of the “standard JUnit message format,” I wouldn’t mind if IntelliJ instead skipped displaying the message in favor of displaying only “Expected” + “Actual” + “<Click to see difference>.” This doesn’t matter to Truth, but it matters to AssertJ under JUnit 4 and to JUnit’s own assertions (4 and 5 both, IIUC).

[Skynet0]

https://youtrack.jetbrains.com/issue/IDEA-238472