Inserts 10000 lines with text to fill the swap file with two levels of pointer
blocks.  Then recovers from the swap file and checks all text is restored.

We need about 10000 lines of 100 characters to get two levels of pointer
blocks.

STARTTEST
:so small.vim
:set nocp fileformat=unix undolevels=-1 viminfo+=nviminfo belloff=all
:e! Xtest
ggdG
:let text = "\tabcdefghijklmnoparstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789abcdefghijklmnoparstuvwxyz0123456789"
:let i = 1
:let linecount = 10000
:while i <= linecount | call append(i - 1, i . text) | let i += 1 | endwhile
:preserve
:" get the name of the swap file
:redir => swapname
:swapname
:redir END
:let swapname = substitute(swapname, '[[:blank:][:cntrl:]]*\(.\{-}\)[[:blank:][:cntrl:]]*$', '\1', '')
:" make a copy of the swap file in Xswap
:set bin
:exe 'sp ' . swapname
:w! Xswap
:echo swapname
:set nobin
:new
:only!
:bwipe! Xtest
:call rename('Xswap', swapname)
:recover Xtest
:call delete(swapname)
:new
:call append(0, 'recovery start')
:wincmd w
:let linedollar = line('$')
:if linedollar < linecount | exe 'wincmd w' | call append(line('$'), "expected " . linecount . " lines but found only " . linedollar) | exe 'wincmd w' | let linecount = linedollar | endif
:let i = 1
:while i <= linecount | if getline(i) != i . text | exe 'wincmd w' | call append(line('$'), i . ' differs') | exe 'wincmd w' | endif | let i += 1 | endwhile
:q!
:call append(line('$'), 'recovery end')
:w! test.out
:qa!
ENDTEST