patch 8.2.2266: Vim9: it can be hard to see where white space is missing Commit: https://github.com/vim/vim/commit/e7a73e07625b64a40671a0007ad38a34cbe9d1ee Author: Bram Moolenaar <Bram@vim.org> Date: Fri Jan 1 19:17:55 2021 +0100 patch 8.2.2266: Vim9: it can be hard to see where white space is missing Problem: Vim9: it can be hard to see where white space is missing. Solution: Mention the text where the error was seen. (closes https://github.com/vim/vim/issues/7580)

Test for writing and reading a file of over 100 Kbyte

1 line: "This is the start"
3001 lines: "This is the leader"
1 line: "This is the middle"
3001 lines: "This is the trailer"
1 line: "This is the end"

STARTTEST
:%d
aThis is the start
This is the leader
This is the middle
This is the trailer
This is the endkY3000p2GY3000p
:w! Xtest
:%d
:e! Xtest
:.w! test.out
3003G:.w >>test.out
6005G:.w >>test.out
:qa!
ENDTEST