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1153 :: unittest or discard string?

• Nycto (orginal) [2015-04-22T17:57:30+02:00] view original

  Hey folks,

  What is the preferred mechanism is for testing libraries that ship with Nim? I see some tests that use the unittest module:

  https://github.com/Araq/Nim/blob/devel/tests/stdlib/thashes.nim

  But the majority seem to define the expected output as a discarded string at the top of a test:

  https://github.com/Araq/Nim/blob/devel/tests/stdlib/tcount.nim

  And some seem to be using a 'doAssert' proc (template? macro?):

  https://github.com/Araq/Nim/blob/devel/tests/stdlib/talgorithm.nim

  I also found a commit that removes the unittest module from one file, which implies it is discouraged:

  https://github.com/Araq/Nim/commit/75f232eb6efa1d213ca84c524ee9119da128d6e3

  That seems counter intuitive to me; the suite/test structure provided by a test framework is more approachable, allows test writers to document exactly what they're checking, and provides natural divisions within a file for improved organization.

  So, back to my original question: What is the preference? I searched the forums briefly, but couldn't find anything discussing this specifically.

  Thanks!

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• Araq (orginal) [2015-04-22T20:32:29+02:00] view original

  There is no preference really. In general I like 'when isMainModule' + 'doAssert' but the tester used to ignore these (we're fixing it). Note that 'doAssert' is not stripped out in release mode. Also compiler tests need the 'discard' section for specifying that something should not compile.

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• PV (orginal) [2015-04-23T16:47:17+02:00] view original

  If you look for a tool one very simple unit test library is described here:

  http://forum.nim-lang.org/t/653

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• Nycto (orginal) [2015-04-23T20:37:46+02:00] view original

  To be clear, I'm ultimately interested in what is preferred when contributing back to the Nim stdlib. PV, your implementation looks like it would work, but I already see 3 different mechanisms in the Nim code base.

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• kirbyfan64sos (orginal) [2015-04-23T23:43:08+02:00] view original

  @Nycto Well, Araq seemingly hates the unittest module. so you can narrow that down to two. :)

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• reactormonk (orginal) [2015-04-26T01:48:24+02:00] view original

  When you test a local change in a stdlib file, put it in the when isMainModule block. Otherwise somewhere in the tests/ directory.

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