Prior to this commit, the modified tests used the strict equality
operator to compare computed values with negative zero. Due to the
semantics of that operator, these tests would spuriously pass if the
value under test was in fact positive zero.
Update the tests to be more precise by instead asserting equality with
the `assert.sameValue` utility method (since that method correctly
distinguishes between negative zero and positive zero).
The global isNaN is not precise at all, and Number.isNaN is an ES6 feature that makes it preferrable to use assert's sameValue for NaN values, as it handles it internally using the comparison.
The `negative` frontmatter tag expresses an expectation for the behavior
of the test file as a whole. The `assert.throws` helper function offers
more fine-grained control over expectations because it may be applied to
specific statements and expressions. This makes it preferable in cases
where it may be used (i.e. when the test body does not describe a syntax
error or early error).
Re-implement assertions for errors to use the `assert.throws` helper
function wherever possible.
Mike Pennisi
rwaldron
Leo Balter
Brian Terlson