commit https://github.com/vim/vim/commit/4b6a6dcbe7bd13170c4884cc17acb1eac2c633d1 Author: Bram Moolenaar <Bram@vim.org> Date: Thu Feb 4 22:49:49 2016 +0100 patch 7.4.1261 Problem: Pending channel messages are garbage collected. Leaking memory in ch_sendexpr(). Leaking memory for a decoded JSON string. Solution: Mark the message list as used. Free the encoded JSON. Don't save the JSON string.

Tests for writefile()

STARTTEST
:source small.vim
:%delete _
:let f = tempname()
:call writefile(["over","written"], f, "b")
:call writefile(["hello","world"], f, "b")
:call writefile(["!", "good"], f, "a")
:call writefile(["morning"], f, "ab")
:call writefile(["", "vimmers"], f, "ab")
:bwipeout!
:$put =readfile(f)
:1 delete _
:w! test.out
:call delete(f)
:qa!
ENDTEST