No placement leaves a pane shorter than its tag and two rows

Placement could split a pane down to a tag and one row, or give a new one
less. Every placement now checks the pane it made and each pane it shrank
against its tag (wrapped at its width) plus two rows: where they lack the
room, the column's tallest pane is halved instead, and where none can give
it the new pane is refused with "no space for a pane in that column"
(ENOSPC over 9P) and closed at the step's end, once its maker is done with
it. splitBelow and splitParent leave two body rows (a boot layout, split
before any row exists, is as before). Re-recorded by name: lookpanes (panes
one or two rows lower) and splitparent (the 6-row squeeze now refuses);
fs.py closes the scratches and long-named panes it no longer needs, since
its 24-row session filled.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

1 files changed, 17 insertions, 17 deletions

diff --git a/test/snapshots/lookpanes.golden b/test/snapshots/lookpanes.golden
index 3c407401..6c0ddb84 100644
--- a/test/snapshots/lookpanes.golden
+++ b/test/snapshots/lookpanes.golden
@@ -14,18 +14,18 @@
 |6:    /tmp/pardes-snap/lookpanes/cwd/alpha/zqonly.txt Save Tty Colla
 |7:    pse Del                                                          /tmp/pardes-snap/lookpanes/cwd/alpha Tty+bash Save Mode Filter
 |8:      1 ONLY-IN-ALPHA                                                 Collapse Del
-== snap clicked-wins grid=130x51 cursor=7,11
-|9:    /tmp/pardes-snap/lookpanes/cwd/beta/both.txt Save Tty Collapse  ls
-|10:     Del                                                            amark.txt  both.txt  pick.txt  twin.txt  zqonly.txt
-|11:      1 BOTH-FROM-BETA
+== snap clicked-wins grid=130x51 cursor=7,12
+|10:    /tmp/pardes-snap/lookpanes/cwd/beta/both.txt Save Tty Collapse  amark.txt  both.txt  pick.txt  twin.txt  zqonly.txt
+|11:     Del
+|12:      1 BOTH-FROM-BETA
 == snap mru-alpha grid=130x51 cursor=72,14
-|12:                                                                     /tmp/pardes-snap/lookpanes/cwd/alpha/pick.txt Save Tty Collaps
+|12:      1 BOTH-FROM-BETA                                               /tmp/pardes-snap/lookpanes/cwd/alpha/pick.txt Save Tty Collaps
 |13:                                                                     e Del
 |14:                                                                       1 PICK-FROM-ALPHA
-== snap mru-beta grid=130x51 cursor=7,14
-|12:    /tmp/pardes-snap/lookpanes/cwd/beta/twin.txt Save Tty Collapse   /tmp/pardes-snap/lookpanes/cwd/alpha/pick.txt Save Tty Collaps
-|13:     Del                                                             e Del
-|14:      1 TWIN-FROM-BETA                                                 1 PICK-FROM-ALPHA
+== snap mru-beta grid=130x51 cursor=7,16
+|14:    /tmp/pardes-snap/lookpanes/cwd/beta/twin.txt Save Tty Collapse     1 PICK-FROM-ALPHA
+|15:     Del
+|16:      1 TWIN-FROM-BETA
 == style mru-beta grid=130x51
 |0: 0-70 #b2c3b8,#1d2824, 71-129 d,#1d2824,
 |1: 0-1 #ffffff,#887455, 2-2 d,#26362d, 3-34 #becfc4,#26362d, 35-64 d,#26362d, 65-66 #ffffff,#887455, 67-67 d,#1d2824, 68-99 #b2c3b8,#1d2824, 100-129 d,#1d2824,
@@ -36,14 +36,14 @@
 |6: 0-1 #ffffff,#496656, 2-2 d,#1d2824, 3-39 #b2c3b8,#1d2824, 40-49 #d3b0d9,#1d2824, 50-64 #b2c3b8,#1d2824, 65-65 d,#608269, 66-129 d,#0d1410,
 |7: 0-2 d,#1d2824, 3-9 #b2c3b8,#1d2824, 10-64 d,#1d2824, 65-66 #ffffff,#496656, 67-67 d,#1d2824, 68-104 #b2c3b8,#1d2824, 105-112 #d3b0d9,#1d2824, 113-129 #b2c3b8,#1d2824,
 |8: 0-0 d,#608269, 1-1 d,#0d1410, 2-6 #59675c,#0d1410, 7-19 #e5eee5,#0d1410, 20-64 d,#0d1410, 65-67 d,#1d2824, 68-80 #b2c3b8,#1d2824, 81-129 d,#1d2824,
-|9: 0-1 #ffffff,#496656, 2-2 d,#1d2824, 3-38 #b2c3b8,#1d2824, 39-46 #d3b0d9,#1d2824, 47-64 #b2c3b8,#1d2824, 65-65 d,#608269, 66-66 d,#0d1410, 67-129 #e5eee5,#0d1410,
-|10: 0-2 d,#1d2824, 3-6 #b2c3b8,#1d2824, 7-64 d,#1d2824, 65-65 d,#608269, 66-66 d,#0d1410, 67-129 #e5eee5,#0d1410,
-|11: 0-0 d,#608269, 1-1 d,#0d1410, 2-6 #59675c,#0d1410, 7-20 #e5eee5,#0d1410, 21-64 d,#0d1410, 65-65 d,#608269, 66-129 d,#0d1410,
-|12: 0-1 #000000,#add38a, 2-2 d,#26362d, 3-38 #becfc4,#26362d, 39-46 #dfbce5,#26362d, 47-64 #becfc4,#26362d, 65-66 #ffffff,#496656, 67-67 d,#1d2824, 68-104 #b2c3b8,#1d2824, 105-112 #d3b0d9,#1d2824, 113-129 #b2c3b8,#1d2824,
-|13: 0-2 d,#26362d, 3-6 #becfc4,#26362d, 7-64 d,#26362d, 65-67 d,#1d2824, 68-72 #b2c3b8,#1d2824, 73-129 d,#1d2824,
-|14: 0-0 d,#608269, 1-1 d,#0d1410, 2-6 #616f64,#0d1410,b 7-20 #e5eee5,#0d1410, 21-64 d,#0d1410, 65-65 d,#608269, 66-66 d,#0d1410, 67-71 #59675c,#0d1410, 72-86 #e5eee5,#0d1410, 87-129 d,#0d1410,
-|15: 0-0 d,#608269, 1-1 d,#0d1410, 2-6 #59675c,#0d1410, 7-64 d,#0d1410, 65-65 d,#608269, 66-66 d,#0d1410, 67-71 #59675c,#0d1410, 72-129 d,#0d1410,
-|16: 0-0 d,#608269, 1-1 d,#0d1410, 2-6 #59675c,#0d1410, 7-64 d,#0d1410, 65-65 d,#608269, 66-66 d,#0d1410, 67-71 #59675c,#0d1410, 72-129 d,#0d1410,
+|9: 0-0 d,#608269, 1-1 d,#0d1410, 2-6 #59675c,#0d1410, 7-64 d,#0d1410, 65-65 d,#608269, 66-66 d,#0d1410, 67-129 #e5eee5,#0d1410,
+|10: 0-1 #ffffff,#496656, 2-2 d,#1d2824, 3-38 #b2c3b8,#1d2824, 39-46 #d3b0d9,#1d2824, 47-64 #b2c3b8,#1d2824, 65-65 d,#608269, 66-66 d,#0d1410, 67-129 #e5eee5,#0d1410,
+|11: 0-2 d,#1d2824, 3-6 #b2c3b8,#1d2824, 7-64 d,#1d2824, 65-65 d,#608269, 66-129 d,#0d1410,
+|12: 0-0 d,#608269, 1-1 d,#0d1410, 2-6 #59675c,#0d1410, 7-20 #e5eee5,#0d1410, 21-64 d,#0d1410, 65-66 #ffffff,#496656, 67-67 d,#1d2824, 68-104 #b2c3b8,#1d2824, 105-112 #d3b0d9,#1d2824, 113-129 #b2c3b8,#1d2824,
+|13: 0-0 d,#608269, 1-1 d,#0d1410, 2-6 #59675c,#0d1410, 7-64 d,#0d1410, 65-67 d,#1d2824, 68-72 #b2c3b8,#1d2824, 73-129 d,#1d2824,
+|14: 0-1 #000000,#add38a, 2-2 d,#26362d, 3-38 #becfc4,#26362d, 39-46 #dfbce5,#26362d, 47-64 #becfc4,#26362d, 65-65 d,#608269, 66-66 d,#0d1410, 67-71 #59675c,#0d1410, 72-86 #e5eee5,#0d1410, 87-129 d,#0d1410,
+|15: 0-2 d,#26362d, 3-6 #becfc4,#26362d, 7-64 d,#26362d, 65-65 d,#608269, 66-66 d,#0d1410, 67-71 #59675c,#0d1410, 72-129 d,#0d1410,
+|16: 0-0 d,#608269, 1-1 d,#0d1410, 2-6 #616f64,#0d1410,b 7-20 #e5eee5,#0d1410, 21-64 d,#0d1410, 65-65 d,#608269, 66-66 d,#0d1410, 67-71 #59675c,#0d1410, 72-129 d,#0d1410,
 |17: 0-0 d,#608269, 1-1 d,#0d1410, 2-6 #59675c,#0d1410, 7-64 d,#0d1410, 65-65 d,#608269, 66-66 d,#0d1410, 67-71 #59675c,#0d1410, 72-129 d,#0d1410,
 |18: 0-0 d,#608269, 1-1 d,#0d1410, 2-6 #59675c,#0d1410, 7-64 d,#0d1410, 65-65 d,#608269, 66-66 d,#0d1410, 67-71 #59675c,#0d1410, 72-129 d,#0d1410,
 |19: 0-0 d,#608269, 1-1 d,#0d1410, 2-6 #59675c,#0d1410, 7-64 d,#0d1410, 65-65 d,#608269, 66-66 d,#0d1410, 67-71 #59675c,#0d1410, 72-129 d,#0d1410,