Relax Kotlin contracts for Executable parameters

[marcphilipp]

• Relax Kotlin contracts for Executable parameters
• Treat Kotlin compiler warnings as errors again

Overview

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I hereby agree to the terms of the JUnit Contributor License Agreement.

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Definition of Done

• There are no TODOs left in the code
• Method preconditions are checked and documented in the method's Javadoc
• Coding conventions (e.g. for logging) have been followed
• Change is covered by automated tests including corner cases, errors, and exception handling
• Public API has Javadoc and @API annotations
• Change is documented in the User Guide and Release Notes

[awelless]

The tests prevent me from approval.
The decision about assertDoesNotThrow I leave to you

[awelless]

The problem is that this test will pass even when no contract is specified. The AT_LEAST_ONE contract allows us to assign vals in lamda body. A test like this would be a better candidate, as it will pass only with AT_LEAST_ONCE or EXACTLY_ONCE contracts. This applies to other changes in this file too.

       @Test
    fun `assertTimeout with value assignment in lambda`() {
        val value: Int

        assertTimeout(ofMillis(500)) {
            value = 10 // Val can be assigned in the message supplier lambda.
            assertEquals(10, value)
        }
    }

[marcphilipp]

Thanks for the suggestion. Applied in 5cac4e3

[awelless]

Although this makes the code compile, I'm still not entirely happy that we must mark this as AT_MOST_ONCE only to make kotlin assertDoesNotThrow compatible with its java counterpart.

If we were able to just run lambda in kotlin, we'd be able to mark all assertDoesNotThrow methods as EXACTLY_ONCE. That being set, this will cause duplication of AssertDoesNotThrow logic which doesn't sound optimal either.

internal inline fun <R> evaluateAndWrap(executable: () -> R): ThrowingSupplier<R> {
    contract {
        callsInPlace(executable, EXACTLY_ONCE)
    }

    return try {
        executable()
    } catch (throwable: Throwable) {
        // logic from java's AssertDoesNotThrow
        UnrecoverableExceptions.rethrowIfUnrecoverable(t)
        throw AssertDoesNotThrow.createAssertionFailedError(messageOrSupplier, t)
    }
}

[marcphilipp]

Done in 0646eba

[marcphilipp]

@awelless Thanks for the review! Do you have time to take another look at my latest changes?

[awelless]

The changes look good, besides the contract in one assertDoesNotThrow.
Approved, assuming the comment will be addressed

[awelless]

This executable should be called EXACTLY_ONCE, as other assertDoesNotThrow methods.

[marcphilipp]

Good catch! Addressed in ef78d82 (#4551)

[marcphilipp]

Superseded by #4551