Report a bug If you spot a problem with this page, click here to create a Bugzilla issue. Improve this page Quickly fork, edit online, and submit a pull request for this page. Requires a signed-in GitHub account. This works well for small changes. If you'd like to make larger changes you may want to consider using local clone.

std.experimental.testing

Advanced unit-testing.
License:
Boost License 1.0.
Authors:
Atila Neves

D's unittest blocks are a built-in feature of the language that allows for easy unit testing with no boilerplate. As a program grows it's usual to need or want more advanced testing features, which are provided by this package.

The easiest way to run tests with the functionality provided is to have a D module implementing a main function similar to this one: 

import std.experimental.testing;

int main(string[] args) {
     return runTests!("name.of.mymodule",
                      "name.of.other.module")(args);
}

This will (by default) run all unittest blocks in the modules passed in as compile-time parameters in multiple threads. Unit tests can be named: to do so simply use the supplied name UDA. There are other supplied UDAs. Please consult the relevant documentation.

As an alternative to writing a program like the one above manually, the included gen_ut_main.d file can be run as a script and will generate such a file. This can be run as part of the build system to recreate the unit test main file. gen_ut_main.d checks to see if the file list has changed and will not regenerate the file if that's not needed.
Examples: 
@name("testTimesTwo")
unittest
{
    int timesTwo(int i) { return i * 2; }

    2.timesTwo.shouldEqual(4);
    3.timesTwo.shouldEqual(6);
}

@name("testRange")
unittest
{
    import std.range: iota;
    iota(3).shouldEqual([0, 1, 2]);
    3.shouldBeIn(iota(5));
}

@name("testIn")
unittest
{
    auto ints = [1, 2, 3, 4];
    3.shouldBeIn(ints);
    1.shouldBeIn(ints);
    5.shouldNotBeIn(ints);
}

@name("testThrows")
unittest
{
    void throwRangeError()
    {
        ubyte[] bytes;
        bytes = bytes[1..$];
    }
    import core.exception: RangeError;
    throwRangeError.shouldThrow!RangeError;
}

//a test that is expected to fail
@name("testOops")
@shouldFail("Bug #1234")
unittest
{
    3.shouldEqual(5); //won't cause the suite to fail
}

//prevent data races
__gshared int i;

@name("sideEffect1")
@singleThreaded //all @singleThreaded tests in a module run in the same thread
unittest
{
    i++;
    i.shouldEqual(1);
}

@name("sideEffect2")
@singleThreaded //all @singleThreaded tests in a module run in the same thread
unittest
{
    i++;
    i.shouldEqual(2);
}