Lazy/shallow tests

[codeactual]

Some Pádraic Brady blog posts articulated some problems which are
definitely prevalent in the test suites. Most tests contain more than one
assertion, and some have perhaps hundreds as they loop over test data (ex.
Test/Analyst/BasicDecimal.php).

It was clear during dev. that it slowed identification of failures. Using
—stop-on-failure and adding details to assertion messages did help, but
those alone probably aren’t clean enough for long-term use.

References:

http://blog.astrumfutura.com/archives/387-Unit-Testing-Multiple-Assertions-And-LazyShallow-Testing-Are-Evil.html
http://blog.astrumfutura.com/archives/388-Unit-Testing-One-Test,-One-Assertion-Why-It-Works.html