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digitalmars.D - Re: Unit tests

Paul D. Anderson Wrote:

 I know there are a lot of D programmers rooting for enhancements to the
unittests in D (and I don't want to re-open that discussion), but are there any
of the best and brightest among us who have developed a module to allow for
named tests and tests that keep running following a failure, etc.
 I apologize if this is a question that's already been asked and answered.

Nick Sabalausky's deferAssert is one take on it, though it's rendered a bit verbose by mixin syntax. I'm writing a small module for this myself -- my main goal is to provide simple and intuitive syntax, and I'm willing to give up a little functionality for that. Here's what a typical unit test might look like: unittest { begin( "testName" ); int foo = 3, baz = 42; bool isOnFire() { return true; } expectEqual! ( foo, 10 ); expectEqual! ( baz, 42 ); expect( !isOnFire(), "danger: code is on fire!" ); } And here is a sample output: Testing 'parser'... [OK] Testing 'lexer'... [FAIL] FAILED TEST: lexNumber lexer.d(517): expected: pos == 6; actual: '8', '6' Testing 'units'... [OK] Testing 'teststuff'... [FAIL] FAILED TEST: testName teststuff.d(12): expected: foo == 10; actual: '3', '10' teststuff.d(14): danger: code is on fire! It integrates quite smoothly so far, using Runtime.moduleUnitTester() to set a custom runner for all unit tests that tracks errors, test names, and so forth and provides the comprehensive output listed above. I also added console text coloring, so on Windows and Linux those "[OK]"s will be in bright green and the "[FAIL]" tags in red. :-) Having to use begin() at the start of the test is a bit of a kludge, and ideally D would allow tests to be named by unittest("testName") { } or some similar syntax. Also, my expectEqual template is hurt somewhat by a limitation in D -- it uses template alias parameters so that it can print a string representation of the symbols that were given to it in a diagnostic message, e.g., "expected: foo == 10". Unfortunately, alias parameters can only alias single D symbols -- so expectEqual!(foo, 10) is okay, but expectEqual!(someArray[1], someFunc()) is not. In another posting here ( http://www.digitalmars.com/webnews/newsgroups.php?art_group=digitalmars D&article_id=105682 ) I suggested allowing template alias parameters to alias compound expressions, which would solve the above problem and make unit testing much more awesome. :D Anyway, as my test module develops into something a little more robust and finished-looking, I'd be happy to post the code if anybody is interested.
Feb 21 2010