scrolloff: keyboard cursor moves keep 3 context rows above/below the cursor (vim scrolloff). One reconcile in Pane.ensureCursorVisible — every keyboard path (normal-mode motions, insert entry/edits, delete/yank/paste/undo/redo) already funnels through it; mouse click/wheel untouched. Clamps: line 0 at top, EOF-at-bottom-row for files (terminals let the vt clamp at the live bottom), margin shrinks on panes shorter than 2*off+1. New scrolloff.snap golden proves j-walk scroll at the margin, gg/top-row reachability, k-walk margin, G bottom clamp. 19/19 snapshots green; no existing goldens changed.

2 files changed, 258 insertions, 0 deletions

diff --git a/test/snapshots/scrolloff.golden b/test/snapshots/scrolloff.golden
new file mode 100644
index 00000000..ed0992ad
--- /dev/null
+++ b/test/snapshots/scrolloff.golden
@@ -0,0 +1,217 @@
+== snap top grid=100x30 cursor=7,2
+|Kill Newcol Tutor Debug Colors NextColor Dump
+|  nm /tmp/pardes-snap/scrolloff/cwd/g.txt Save Del  nm /tmp/pardes-snap/scrolloff/cwd Del
+|     1 line 1
+|     2 line 2                                       g.txt
+|     3 line 3
+|     4 line 4
+|     5 line 5
+|     6 line 6
+|     7 line 7
+|     8 line 8
+|     9 line 9
+|  nm /tmp/pardes-snap/scrolloff/cwd Del
+|
+|  g.txt
+|
+|
+|
+|
+|
+|
+|
+|  nm /tmp/pardes-snap/scrolloff/cwd Del
+|
+|  g.txt
+|
+|
+|
+|
+|
+|
+== snap edge grid=100x30 cursor=7,7
+|Kill Newcol Tutor Debug Colors NextColor Dump
+|  nm /tmp/pardes-snap/scrolloff/cwd/g.txt Save Del  nm /tmp/pardes-snap/scrolloff/cwd Del
+|     1 line 1
+|     2 line 2                                       g.txt
+|     3 line 3
+|     4 line 4
+|     5 line 5
+|     6 line 6
+|     7 line 7
+|     8 line 8
+|     9 line 9
+|  nm /tmp/pardes-snap/scrolloff/cwd Del
+|
+|  g.txt
+|
+|
+|
+|
+|
+|
+|
+|  nm /tmp/pardes-snap/scrolloff/cwd Del
+|
+|  g.txt
+|
+|
+|
+|
+|
+|
+== snap scrolled1 grid=100x30 cursor=7,7
+|Kill Newcol Tutor Debug Colors NextColor Dump
+|  nm /tmp/pardes-snap/scrolloff/cwd/g.txt Save Del  nm /tmp/pardes-snap/scrolloff/cwd Del
+|     2 line 2
+|     3 line 3                                       g.txt
+|     4 line 4
+|     5 line 5
+|     6 line 6
+|     7 line 7
+|     8 line 8
+|     9 line 9
+|    10 line 10
+|  nm /tmp/pardes-snap/scrolloff/cwd Del
+|
+|  g.txt
+|
+|
+|
+|
+|
+|
+|
+|  nm /tmp/pardes-snap/scrolloff/cwd Del
+|
+|  g.txt
+|
+|
+|
+|
+|
+|
+== snap jdown grid=100x30 cursor=7,7
+|Kill Newcol Tutor Debug Colors NextColor Dump
+|  nm /tmp/pardes-snap/scrolloff/cwd/g.txt Save Del  nm /tmp/pardes-snap/scrolloff/cwd Del
+|     6 line 6
+|     7 line 7                                       g.txt
+|     8 line 8
+|     9 line 9
+|    10 line 10
+|    11 line 11
+|    12 line 12
+|    13 line 13
+|    14 line 14
+|  nm /tmp/pardes-snap/scrolloff/cwd Del
+|
+|  g.txt
+|
+|
+|
+|
+|
+|
+|
+|  nm /tmp/pardes-snap/scrolloff/cwd Del
+|
+|  g.txt
+|
+|
+|
+|
+|
+|
+== snap end grid=100x30 cursor=7,10
+|Kill Newcol Tutor Debug Colors NextColor Dump
+|  nm /tmp/pardes-snap/scrolloff/cwd/g.txt Save Del  nm /tmp/pardes-snap/scrolloff/cwd Del
+|    33 line 33
+|    34 line 34                                      g.txt
+|    35 line 35
+|    36 line 36
+|    37 line 37
+|    38 line 38
+|    39 line 39
+|    40 line 40
+|    41
+|  nm /tmp/pardes-snap/scrolloff/cwd Del
+|
+|  g.txt
+|
+|
+|
+|
+|
+|
+|
+|  nm /tmp/pardes-snap/scrolloff/cwd Del
+|
+|  g.txt
+|
+|
+|
+|
+|
+|
+== snap kup grid=100x30 cursor=7,5
+|Kill Newcol Tutor Debug Colors NextColor Dump
+|  nm /tmp/pardes-snap/scrolloff/cwd/g.txt Save Del  nm /tmp/pardes-snap/scrolloff/cwd Del
+|    30 line 30
+|    31 line 31                                      g.txt
+|    32 line 32
+|    33 line 33
+|    34 line 34
+|    35 line 35
+|    36 line 36
+|    37 line 37
+|    38 line 38
+|  nm /tmp/pardes-snap/scrolloff/cwd Del
+|
+|  g.txt
+|
+|
+|
+|
+|
+|
+|
+|  nm /tmp/pardes-snap/scrolloff/cwd Del
+|
+|  g.txt
+|
+|
+|
+|
+|
+|
+== snap top2 grid=100x30 cursor=7,2
+|Kill Newcol Tutor Debug Colors NextColor Dump
+|  nm /tmp/pardes-snap/scrolloff/cwd/g.txt Save Del  nm /tmp/pardes-snap/scrolloff/cwd Del
+|     1 line 1
+|     2 line 2                                       g.txt
+|     3 line 3
+|     4 line 4
+|     5 line 5
+|     6 line 6
+|     7 line 7
+|     8 line 8
+|     9 line 9
+|  nm /tmp/pardes-snap/scrolloff/cwd Del
+|
+|  g.txt
+|
+|
+|
+|
+|
+|
+|
+|  nm /tmp/pardes-snap/scrolloff/cwd Del
+|
+|  g.txt
+|
+|
+|
+|
+|
+|
diff --git a/test/snapshots/scrolloff.snap b/test/snapshots/scrolloff.snap
new file mode 100644
index 00000000..e231e8de
--- /dev/null
+++ b/test/snapshots/scrolloff.snap
@@ -0,0 +1,41 @@
+# scrolloff: keyboard motion keeps 3 context rows above/below the cursor,
+# clamped at file boundaries (cursor may reach the top/bottom body row there)
+lines g.txt 40
+start 30 100
+wait 8000 g.txt
+stable 700 20000
+# right-click the g.txt name in the greeting ls -> file pane, 9 body rows
+press right 4 4
+release right 4 4
+wait 10000 line 3
+stable 700 15000
+press left 10 3
+release left 10 3
+stable 400 5000
+# (b) gg: cursor CAN sit on the top body row, no forced scroll
+key g g
+stable 400 5000
+snap top
+# (a) five j's reach the bottom margin (visual row 5 of 9) without scrolling...
+key j j j j j
+stable 400 5000
+snap edge
+# ...the sixth j scrolls: view slides one line, cursor holds the margin
+key j
+stable 400 5000
+snap scrolled1
+key j j j j
+stable 400 5000
+snap jdown
+# (d) G: bottom clamp, view stops at EOF-at-bottom, cursor on the bottom row
+key G
+stable 400 5000
+snap end
+# (c) k-walk up: cursor climbs to the top margin, then the view scrolls
+key k k k k k k k k
+stable 400 5000
+snap kup
+# (b) again from deep in the file: gg puts the cursor back on the top row
+key g g
+stable 400 5000
+snap top2