There are some problems with nyc:
* The coverage numbers aren't useful in our case because most of the
code is executed outside the test process (the test code is mostly
API client logic).
* nyc messes with line numbers, which makes it much harder to debug
problems.
* We're seeing frequent SIGABRT crashes while nyc is printing the
results table. I'm not sure if nyc is the cause of the crashes, or
if it's making a race condition worse, or if the crashes have
nothing to do with nyc, but we don't lose much by removing it so
we might as well see if the crash frequency improves.
This makes it much easier to see why a test is failing. Before, a
`helper.waitFor()` failure would simply cause the test to time out.
Now an exception is displayed.
Before this change, the `author` attribute was silently discarded
during `.map()` iteration and the name of the attribute to remove was
included twice with two different values.
Before this commit, the callback passed to `.map()` during attribute
removal was a normal function, not an arrow function. This meant that
the value of `this` in the function body depended on how the callback
was invoked. In this case, the callback was invoked without any
explicit context (it was not called as a method, nor was it called via
`.call()`, `.apply()`, or `.bind()`). Without any explicit context,
the value of `this` depends on strict mode. Currently the function is
in sloppy mode, so `this` refers to the "global this" object (a.k.a.,
`window`). It doesn't make sense for the callback to reference
`window.author`, so I'm assuming the previous behavior was a bug.
Now the function is an arrow function, so the value of `this` comes
from the enclosing lexical context, which in this case is the
AttributeManager object. I believe that was the original intention.
This makes it possible for plugin backend tests to do
`require('ep_etherpad-lite/tests/backend/common')` to access the API
key (among other things).
Eventually we probably should reverse these (move `tests/` to
`src/tests/` and make `tests/` a symlink to `src/tests/`) and move
`bin/` to `src/bin/` so that we can avoid the top-level `package.json`
mess.
