# y -> p round-trips through the core's own yank register (regression: p used
# to request the SYSTEM clipboard via OSC 52, which plain terminals — and this
# harness — never answer, so paste silently no-oped). Pins helix placement:
# a linewise yank (x) pastes as whole lines below (p) / above (P), a charwise
# yank (v) splices inline after the selection.
lines f.txt 5
start 31 100 f.txt
wait 8000 Newcol Joincol
wait 8000 line 5
stable 700 20000
# linewise: x-select line 2, yank, move down, paste below line 3
press left 8 5
release left 8 5
stable 400 5000
key x y j p
stable 400 5000
snap linewise-below
# P from the pasted line: its copy lands above
key x y P
stable 400 5000
snap linewise-above
# charwise: v-select two chars of line 1, yank, paste splices after them
press left 8 4
release left 8 4
stable 400 5000
key v l y p
stable 400 5000
snap charwise-inline
# a BLANK line yanks as a bare "\n": the block is empty, lineCount says 0
# lines, and every `n - 1` in the linewise paste used to underflow — panic on
# y then p. It pastes as one empty line.
key o
key esc
settle 100
key y p
stable 400 5000
snap blankline