feat: add yy to copy mode

[BrettKulp]

add yy to copymode to copy current line in normal mode

[leohenon]

copy mode pending y survives other handled keys.

Example: y j y triggers yy.

Since yy is the only supported y operator here, you can clear pending y when the next key is not y.

[leohenon]

The 150ms flash delay is fine, but maybe copy mode should probably exit immediately after yy so the timeout doesn't keep copy mode active during the flash.

Also I think normal prompt yank flash uses 70ms, maybe we should also use 70ms here for consistency?

[leohenon]

This fixes y j y, but pending y is still cleared too late. Keys like H/M/L and v/V return before the clear, so pending y can still survive.

We should clear pending y near the top of copy mode handling before other handlers run.

[leohenon]

we should probably also add a test for this, e.g. y H y should not trigger yy.

[BrettKulp]

My bad. Will fix and add test

[BrettKulp]

This should be better now. I noticed that line 1049 and 1067 both have the same issue f H k will finish the jump to the next k on the line after the cursor moves. Would it be better to clear pending before the return always unless the key needs to stay in pending state?

[leohenon]

Thanks. Yes theres also an ordering issue for f/F/t/T and z but that should be fixed separately.

The y fix/test look good. Just a few things:

• git diff --check fails on trailing whitespace in the new test
• resolve the merge conflict
• please revert the immediate copy mode exit after yy as it makes the flash render in the wrong place. That
  was my bad, preserving the correct flash is more important.

Other than that, this should be good.

[leohenon]

Thanks, just cleaned up a couple more things I noticed:

yy was linewise, but should be charwise so pasting into the prompt doesn’t add an extra line.

The exit delay was still 150ms but should match the 70ms yank flash.

Also simplified the highlight code and stopped exposing the flash state.

Implemented on ocv in 9049c0b