Vim fill command line with currently highlighted word in substitution

Question

I have incsearch on, so when I type :s/thingS it will highlight the thingS part of thingSoFar in the below text

see, this thing is the thingSoFar thing

When I am typing that command line with my cursor at the first column, first the t, then th, then thi of "this" are highlighted. When I type the n, it no longer matches this, so the highlighting jumps to the first thing's thin. When I type g the highlighting remains on that word. Then when I type S it jumps forwards to highlight the thingS of thingSoFar. Standard incsearch behaviour.

Now, I would like to <C-r><C-w> the currently highlighted word, rather than the word that my cursor was on when I entered command line mode.

E.g., I put my cursor on the first column in the line above (on the s of see)

Now I type

:s/thingS<C-r><C-w>

I would like my command line to be filled like this:

:s/thingSoFar

instead I get this

:s/thingSsee

How can I actually get the result I want? How can I complete the word I'm typing in the command line with the currently incsearch-highlighted word?

Answer 1

There is :help c_ctrl-l, which inserts one character of the first match:

:s/thingS
:s/thingSo       " <C-l>
:s/thingSoF      " <C-l>
:s/thingSoFa     " <C-l>
:s/thingSoFar    " <C-l>

but a) the characters come from the first match, which is probably not that useful, and b) it only inserts one character, which possibly means doing lots of <C-l>s to get what you want. In this case, pressing <C-l> four times is not a lot worse than pressing <C-r><C-w> once but still.

At a much higher level, you have the venerable CmdlineComplete plugin.

Answer 2

running vim -u NONE and activating set incsearch does result in your desired behaviour.

<C-R><C-W> does fill in the entire word thingSoFar. Within substitution and search on the cmdline.

I am not able to provide you a specific patch from the repository which implements this functionality but it is documented since this commit to be the default behaviour for incsearch: Version 7.0226