The `arrayContains` function has a number of deficiencies which make it
inappropriate for Test262:
- It apparently isn't very useful: despite being available for over 7
years, fewer than ten tests use it
- It's misleading: its documentation reads, "Verify that a subArray is
contained within an array." In reality, it only verifies that all the
elements of one array are present in another--order does not matter.
- It's not ergonomic for test authors: it has been misused to create
tests that were prone to false positives [1]
- It's not ergonomic for implementers: ostensibly designed for use with
`assert`, the failure messages produced by tests that use it do not
necessarily have very much context
All code in the "harness" directory adds to the total amount of
project-specific information which contributors are expected to to
learn. In light of the above deficiencies, the burden of this particular
harness file is unjustified.
Remove the harness file and its associated tests. Update the tests which
depend on it to express their expectations using alternate methods, and
strengthen the tests to assert element order wherever appropriate.
[1] https://github.com/tc39/test262/pull/3289
Mike Pennisi
Philip Chimento