cj on Extending JavaScript with inline unit tests

Comment on Extending JavaScript with inline unit tests

Here's a simple implementation without sweet.js:

  var inlineTest = function(fn, tests) {
    (tests || []).forEach(function(test){
      if (fn.apply(this, test[0]) !== test[1]) {
        throw new Error('Failed inline unit test with args: ' + test[0]);
      }
    });
    return fn;
  };

  var square = inlineTest(function(n){
    return n * n;
  }, [
    [[2],4], // [[arrayOfArguments], expectedResult]
    [[3],5]  // <-- This test will throw an error
  ]);

EDIT: Change fn.call to fn.apply

tiles 12y

Nice. If you wanted to go even more inline:

    Function.prototype.where = function () {
        var fn = this, tests = [].slice.apply(arguments);
        (tests || []).forEach(function(test){
          if (fn.call(this, test[0]) !== test[1]) {
            throw new Error('Failed inline unit test with args: ' + test[0]);
          }
        });
        return fn;
    };
    
      var square = function(n){
        return n * n;
      }.where(
        [[2], 4], // [[arrayOfArguments], expectedResult]
        [[3], 5]  // <-- This test will throw an error
      );

sergimansillaOP12y

Cool, nice and clean :)

As I mention in the post though, mine is just a very simple macro. But it is enough to show how easy is to modify the language to fit different scenarios, such as testing. The macro could probably be expanded and improved a lot to fit much more complex scenarios like real Contract-based languages have.

camus2 12y

you just gave me an idea for a "typechecking" api.thanks.

jordanwallwork 12y

I wrote something like this once, never did anything with it but you might find it useful: http://jordanwallwork.co.uk/2013/01/faking-typed-function-ov...

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