https://github.com/mpeterv/luacheck/pull/81#issuecomment-261099606

> If you really want to use bleeding-edge version you should get the
> rockspec from master branch, not a fixed commit ...
> The correct way to install from a specific commit is cloning that
> commit and running "luarocks make" from project directory. The reason
> is that running "install" or "build" on an scm rockspec fetches
> sources from master but uses build description from the rockspec
> itself, which may be outdated.

Change shada reencoding tests to check for
correct handling of UTF-8 and binary strings.

Delete enc=latin1 json tests.

Problem: If CTRL-C is mapped, it does not interrupt :global output.
Solution: clear `mapped_ctrl_c` during :global.

Closes #5267

Helped-by: oni-link <knil.ino@gmail.com>

Closes #3529
Closes #5241

In Vim,
    :echo system('cat - &', 'foo')
works because for both system() and :! Vim writes input to a temp file and uses
shell syntax to redirect the file to the backgrounded `cat` (get_cmd_output()
.. make_filter_cmd()).

In Nvim,
    :echo system('cat - &', 'foo')
fails because we write the input directly via pipes (shell.c:do_os_system()),
but (per POSIX[1]) backgrounded process input stream is redirected from
/dev/null (unless overridden by shell redirection; supported only by some shells
[2]), so our writes are ignored, the process exits quickly, and if we are
writing data larger than the buffer size we'll see EPIPE.

This still works:
    :%w !tee > foo1358.txt &
but this does not:
    :%w !tee foo1358.txt &
though it *should* (why doesn't it?) because we still do the temp file dance
in do_bang() .. do_filter().

[1] http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_09_03_02
[2] http://unix.stackexchange.com/a/71218

These tests are essentially affirming a regression vs Vim. In Vim,
    :echo system('cat - &', 'foo')
returns "foo", because Vim internally wraps the command with shell-specific
syntax to redirect the streams from /dev/null[1].

That can't work in Nvim because we use pipes directly (instead of temp files)
and don't wrap the command with shell-specific redirection syntax.

References #3529
References #5241

[1] http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_09_03_02

Check `exists('b:term_title')` to avoid the BufReadCmd for already-initialized
:terminal buffers.

Move the test for `:argadd`.
Add a test for `:edit<CR>`.
Tweak comments and code style.

Delete the CWD using nvim instead of the external lua/test runner process.

Closes #5291

Restores behaviour identical to Vim. If the user calls the VimScript
function 'getcwd()' and the working directory cannot be found (for
example because the directory has been deleted since the last time it
was used) an empty string needs to be returned instead of throwing an
error.

When a new tabpage gets created it will copy the local working directory
of the previous one, if there is any.