Include parameter names in default name of @ParameterizedTest

[vlsi]

Suppose I have a test:

    @ParameterizedTest
    @MethodSource("implementationsAndIps")
    public void test(String httpImplementation, String targetHost, InetAddress sourceIp,
                     WireMockServer server, JMeterVariables vars) throws SocketException {

The result looks unreadable:

[3] HttpClient4, 127.0.0.1, /127.0.0.1
[1] HttpClient4, 127.0.0.1, /fe80:0:0:0:0:0:0:1%lo0
[7] Java, 127.0.0.1, /fe80:0:0:0:0:0:0:1%lo0
[4] HttpClient4, [::1], /fe80:0:0:0:0:0:0:1%lo0
[5] HttpClient4, [::1], /0:0:0:0:0:0:0:1%lo0
[8] Java, 127.0.0.1, /0:0:0:0:0:0:0:1%lo0
[10] Java, [::1], /fe80:0:0:0:0:0:0:1%lo0

It does not really help if the test fails.
That means every time I use @ParameterizedTest I have to declare test name explicitly.
That is sad.

What if JUnit generated something like

[3] httpImplementation=HttpClient4, targetHost=127.0.0.1, sourceIp=/127.0.0.1
[1] httpImplementation=HttpClient4, targetHost=127.0.0.1, sourceIp=/fe80:0:0:0:0:0:0:1%lo0
...

?

It would make lots of tests and test failures easier to understand.
I'm OK if it is {arguments_with_names}. Then I could create @ParameterizedTestWithArgNames annotation that uses detailed name.

PS. I've seen #1154, however, I don't really want to deal and/or declare resolvers.

[sbrannen]

Tentatively slated for 5.6 M1 solely for the purpose of team discussion and triaging.

[sbrannen]

FYI: this would need to be an opt-in feature. In addition, parameter names are not always present in the compiled byte code. To include them in the byte code, the test code must be compiled with the -parameters compiler flag.

[vlsi]

You assume I use Java, however, Kotlin does retain parameter names always 😉

[marcphilipp]

@sbrannen Could we check whether parameter names are present and include them only if so?

[sbrannen]

@sbrannen Could we check whether parameter names are present and include them only if so?

Yes. See java.lang.reflect.Parameter.isNamePresent().

[marcphilipp]

Team Decision: Introduce new {arguments_with_names} pattern and make it the default. Only include parameter names if present in bytecode and parameter types are known (e.g. not for ArgumentsAccessor and ArgumentsAggregator).