I am working on a simple project created with DUB[1].
When unit tests the output reads really cryptic to me; for example:

    $ dub test
    Generating test runner configuration '__test__library__' for 'library' (library).
    Target dunit 1.0.11 is up to date. Use --force to rebuild.
    Building d-etudes ~master configuration "__test__library__", build type unittest.
    Compiling using dmd...
    Linking...
    Running ./__test__library__
    core.exception.AssertError@source/e002.d(111): unittest failure
    ----------------
    ./__test__library__(void detudes.e002.__unittest_fail(int)+0x28) [0x4bf508]
    ./__test__library__(void detudes.e002.__unittestL106_4()+0x17b) [0x4bf47b]
    ./__test__library__(void detudes.e002.__modtest()+0xe) [0x4bf48e]
    ./__test__library__(int core.runtime.runModuleUnitTests().__foreachbody2(object.ModuleInfo*)+0x34) [0x4d0d0c]
    ./__test__library__(int object.ModuleInfo.opApply(scope int delegate(object.ModuleInfo*)).__lambda2(immutable(object.ModuleInfo*))+0x1c) [0x4c1ab4]
    ./__test__library__(int rt.minfo.moduleinfos_apply(scope int delegate(immutable(object.ModuleInfo*))).__foreachbody2(ref rt.sections_elf_shared.DSO)+0x46) [0x4c7422]
    ./__test__library__(int rt.sections_elf_shared.DSO.opApply(scope int delegate(ref rt.sections_elf_shared.DSO))+0x41) [0x4c7499]
    ./__test__library__(int rt.minfo.moduleinfos_apply(scope int delegate(immutable(object.ModuleInfo*)))+0x20) [0x4c73bc]
    ./__test__library__(int object.ModuleInfo.opApply(scope int delegate(object.ModuleInfo*))+0x20) [0x4c1a90]
    ./__test__library__(runModuleUnitTests+0x98) [0x4d0bd8]
    ./__test__library__(void rt.dmain2._d_run_main(int, char**, extern (C) int function(char[][])*).runAll()+0x17) [0x4c4147]
    ./__test__library__(void rt.dmain2._d_run_main(int, char**, extern (C) int function(char[][])*).tryExec(scope void delegate())+0x2a) [0x4c40fa]
    ./__test__library__(_d_run_main+0x1d2) [0x4c407a]
    ./__test__library__(main+0x20) [0x48a968]
    /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf5) [0x7f1f751d9ec5]
    Error executing command test:
    Program exited with code 1

It is almost impossible for me to comprehend anything useful out of this, except that, well, the tests have failed :-)

Is there any compiler switch, argument to `assert` or trick to make `unittest` output more helpful messages when failing?

[1] https://github.com/bahmanm/d-etudes

On Monday 07 September 2015 13:57, Bahman Movaqar wrote:

> I am working on a simple project created with DUB[1].
> When unit tests the output reads really cryptic to me; for
> example:
> 
>      $ dub test
[...]
>      core.exception.AssertError@source/e002.d(111): unittest
> failure
[...]
> 
> It is almost impossible for me to comprehend anything useful out of this, except that, well, the tests have failed :-)

From that one line I left intact above, you should also be able to figure out that it's the test in source/e002.d, line 111 that failed.

> Is there any compiler switch, argument to `assert` or trick to make `unittest` output more helpful messages when failing?

You can pass a custom message as a second argument to assert:
assert(condition, "message goes here");

I think there are testing libraries/frameworks around that mean to provide more than the basic built-in things. But I haven't tried any, so I can't recommend anything. Try searching for "test" here: http://code.dlang.org/

On Monday, 7 September 2015 at 12:06:09 UTC, anonymous wrote:
> On Monday 07 September 2015 13:57, Bahman Movaqar wrote:
>>      $ dub test
> [...]
>>      core.exception.AssertError@source/e002.d(111): unittest
>> failure
> [...]
> From that one line I left intact above, you should also be able to figure out that it's the test in source/e002.d, line 111 that failed.

True.  That I had already figured out.  I was actually hoping for something like Groovy's assert messages[1], if possible.

>> Is there any compiler switch, argument to `assert` or trick to make `unittest` output more helpful messages when failing?
>
> You can pass a custom message as a second argument to assert:
> assert(condition, "message goes here");

Thanks.  This is indeed helpful.  OT but where can I view the documentation for `unittest` and `assert`?

[1] http://docs.groovy-lang.org/next/html/documentation/core-testing-guide.html#_power_assertions

On Monday 07 September 2015 14:12, Bahman Movaqar wrote:

> Thanks.  This is indeed helpful.  OT but where can I view the documentation for `unittest` and `assert`?

unittest: http://dlang.org/unittest.html
assert: http://dlang.org/expression.html#AssertExpression (I don't know why
it's considered an expression and not a statement.)

On Monday, 7 September 2015 at 12:16:14 UTC, anonymous wrote:
> On Monday 07 September 2015 14:12, Bahman Movaqar wrote:
>
>> Thanks.  This is indeed helpful.  OT but where can I view the documentation for `unittest` and `assert`?
>
> unittest: http://dlang.org/unittest.html
> assert: http://dlang.org/expression.html#AssertExpression (I don't know why
> it's considered an expression and not a statement.)

Thanks.

On Monday, 7 September 2015 at 12:16:14 UTC, anonymous wrote:
> On Monday 07 September 2015 14:12, Bahman Movaqar wrote:
>
>> Thanks.  This is indeed helpful.  OT but where can I view the documentation for `unittest` and `assert`?
>
> unittest: http://dlang.org/unittest.html
> assert: http://dlang.org/expression.html#AssertExpression (I don't know why
> it's considered an expression and not a statement.)

int main()
{
	int a = 1;
	a || assert(false);
	return 0;
}

On Monday, 7 September 2015 at 11:57:25 UTC, Bahman Movaqar wrote:
> I am working on a simple project created with DUB[1].
> When unit tests the output reads really cryptic to me; for example:

Try using DUnit, it gives you much more readable fail messages:

https://github.com/nomad-software/dunit

On Monday, 7 September 2015 at 12:58:58 UTC, Gary Willoughby wrote:
> On Monday, 7 September 2015 at 11:57:25 UTC, Bahman Movaqar wrote:
>> I am working on a simple project created with DUB[1].
>> When unit tests the output reads really cryptic to me; for example:
>
> Try using DUnit, it gives you much more readable fail messages:
>
> https://github.com/nomad-software/dunit

It's in the dub repository too:

http://code.dlang.org/packages/dunit