vim-patch:7.4.1588

Problem:    Crash when assert_equal() runs into a NULL string.
Solution:   Check for NULL. (Dominique) Add a test.

https://github.com/vim/vim/commit/f1551964448607f8222de2d8f0992ea43eb2fe67

Problem:    Old style test for quickfix.
Solution:   Turn test 96 into a new style test.

https://github.com/vim/vim/commit/1ff2b64b11e7d263c6853745d5e594bd8f94b91e

Problem:    syn-cchar defined with matchadd() does not appear if there are no
            other syntax definitions which matches buffer text.
Solution:   Check for startcol. (Ozaki Kiichi, haya14busa, closes vim/vim#757)

https://github.com/vim/vim/commit/4d585022023b96f6507e8cae5ed8fc8d926f5140

win32 handles dot-prefixed files just fine; Nvim-on-Windows does not
perpetuate the Vim-on-Windows behavior of avoiding dot-prefixed files.

Attempt to avoid "Permission denied" on Windows potentially caused by open
filepath handle in sibling process.

In Windows Lua's os.tmpname() returns relative paths starting with \s,
prepend them with $TEMP to generate a valid path.

In OS X os.tmpname() returns paths in '/tmp' but they should be in
'/private/tmp'. We cannot use os_name() for platform detection because
some tests use tempname() before nvim is spawned, instead use one of the
following:

1. Set SYSTEM_NAME environment variable before calling the tests, it
   is set from CMAKE_SYSTEM_NAME(i.e. uname -s or 'Windows')
2. Call uname -s
3. Assume windows