Add documentation for isOverrideFunction and getUnitTests traits

[jacob-carlborg]

I guess this shouldn't be pulled at least until the pull request for isOverrideFunction is merged. getUnitTests is already implemented.

[ghost]

W.r.t. getUnitTests: Could you please add the following code snippet, it will show people how to avoid running the tests automatically:

import core.runtime;

shared static this()
{
    Runtime.moduleUnitTester = { return true; };
}

unittest
{
    assert(0);
}

This will stop the unittests from running, but continue execution into main (one can return false to avoid calling main as well). Also make a note that Runtime.moduleUnitTester must be set in a module constructor, and not in the main function (because the unittests are executed before main).

[ghost]

Btw, is it possible to make __traits(getUnitTests) work with a ModuleInfo? It would allow this code:

void main()
{
    foreach (m; ModuleInfo)
    {
        foreach (test; __traits(getUnitTests, m))
        {
            // run each test for every module
        }
    }
}

Otherwise we are forced to have a single module which imports all other modules in order to be able to use __traits(getUnitTests).

[ghost]

One other thing I have w.r.t. this feature, __traits(getUnitTests) doesn't seem to work recursively when you call it on a module, it only picks up the unittests in a module but not the unittests in the aggregates in the module. So currently one has to iterate through all aggregates somehow (and recursively) to find all the unittests in a module, but I would prefer if the compiler did this automatically when passed a module, because this is likely difficult to implement in library code.

[jacob-carlborg]

@AndrejMitrovic W.r.t. getUnitTests: Could you please add the following code snippet, it will show people how to avoid running the tests automatically

Yes, I can do that.

[jacob-carlborg]

Btw, is it possible to make __traits(getUnitTests) work with a ModuleInfo? It would allow this code

No, I don't think so. At least not easily. __traits is designed to work at compile time. In the example you're iterating runtime data. One also need to use getUnitTests at compile time to be able to access UDA's.

The unit tests are already accessible from the module info. What would this gain? Accessing the individual unit test functions and not only the wrapper? Or accessing UDA's?

Otherwise we are forced to have a single module which imports all other modules in order to be able to use __traits(getUnitTests).

Yeah, I know, that's a problem. I have another pull request that is intended to solve this problem. Doing the same as RTInfo but for modules instead of types. But that was not entirely liked. dlang/dmd#2271

[jacob-carlborg]

One other thing I have w.r.t. this feature, __traits(getUnitTests) doesn't seem to work recursively when you call it on a module, it only picks up the unittests in a module but not the unittests in the aggregates in the module.

Yes, that's how the rest of these traits work.

So currently one has to iterate through all aggregates somehow (and recursively) to find all the unittests in a module, but I would prefer if the compiler did this automatically when passed a module, because this is likely difficult to implement in library code.

I thought that was fairly easy solvable using __traits(allMembers).

[ghost]

I thought that was fairly easy solvable using __traits(allMembers).

Well if it's implementable in a library I suggest we add something like this to Phobos, e.g. a getAllUnittests template which takes an alias to a module and extracts all unittests in that module.

The unit tests are already accessible from the module info. What would this gain? Accessing the individual unit test functions and not only the wrapper? Or accessing UDA's?

Both! But yeah __traits is the wrong way around this, the ModuleInfo itself would likely need to have an array of unittests instead.

[jacob-carlborg]

Added example of overriding the default unit test runner.

[9rnsr]

To do this, import core.runtime; is necessary.

[jacob-carlborg]

Right. I'll fix it.

[jacob-carlborg]

Done.

[jacob-carlborg]

Semicolon, done.

[9rnsr]

OK, LGTM.

[jacob-carlborg]

Thanks 😃