Hope this will make people using feed_command less likely: this hides bugs.
Already found at least two:
1. msgpackparse() will show internal error: hash_add() in case of duplicate
keys, though it will still work correctly. Currently silenced.
2. ttimeoutlen was spelled incorrectly, resulting in option not being set when
expected. Test was still functioning somehow though. Currently fixed.
When test/functional/eval/system_spec.lua is run on its own,
helpers.os_name() was being called before a session had been created.
This caused that describe block to fail.
Turning printargs_path into a function delays the call of
helpers.os_name() until the test is being run, which ensures a session
is available.
Do _not_ set v:shell_error on parameter validation error.
system([...]) does not invoke a shell, so this change is somewhat
questionable. But `:help v:shell_error` is sufficiently vague to allow
-1 in this case.
Closes#3529Closes#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
