Surround does not behave as it should in a few cases

[xconverge]

Great work, your way of implementing the surround plugin is pretty nice! Here are some findings I had that I wanted to at least document. It is kind of nitpicking but also takes away quite a bit from the usage of the plugin when things are off by one etc, I anticipate some people might mention things on slack related to these.

Here are a few cases that I found surround does weird things:

te|st
ysaw"
expected: "test"
actual: t"est"
(this only happens on the last line of a file I think...)

te|st
ysas"
expected: "test"
actual: test""

visual line select, [ ] is selection

[test
test]

S"
expected:

"
test
test
"

actual:

"test
test"

Backspace when entering a tag should remove the previous character, not add (similar to searchstate)

surround t should trigger the same thing as <, not surround with t

Should not be able to surround using any character, and b and B should be brackets
check out this data structure for the only valid pairs besides tags, I think it is correct:

https://github.com/xconverge/Vim/blob/8c24283d2801596378f9d34dee4b27b592f8968f/src/surround/surround.ts#L29

[kitsu]

I ran into the t for tag one already. Also some kind of feedback during tag input would be nice.
Over all great feature though, the one thing I really missed most from Vim.

[xconverge]

feedback during tag input was added to master, will show in the status bar atleast for now

[xconverge]

fixed most in #1289