size says its limits, keeps every pane its rows, and ptys follow their panes

size refused an out-of-range line without saying the range, took a size
too small for the panes (leaving bodies of no rows), and a terminal
squeezed to its tag kept a pty of its old size. The refusal now names
20x6 to 4096x4096 (a bare size is EINVAL like any malformed line), a size
that would leave any pane less than its tag and 2 rows is refused and
undone, and a terminal's pty is resized with its pane down to one row
(only a folded or unplaced one keeps its grid).

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

1 files changed, 14 insertions, 0 deletions

diff --git a/src/layout.zig b/src/layout.zig
index 4c974fb7..bdef9675 100644
--- a/src/layout.zig
+++ b/src/layout.zig
@@ -433,6 +433,20 @@ pub fn placedRoomy(p: *Pardes, id: usize, before: *const [MAX_PANES]Rect) bool {
     return true;
 }
 
+/// Whether every unfolded pane sharing its column has its tag and
+/// `min_body_rows` (one alone in its column always fits).
+pub fn everyPaneRoomy(p: *Pardes) bool {
+    compute(p);
+    for (0..p.ncol) |c| {
+        if (p.col_n[c] < 2) continue;
+        for (p.col_panes[c][0..p.col_n[c]]) |k| {
+            const pane = p.panes[k] orelse continue;
+            if (!pane.collapsed and p.rects[k].h < minRows(p, k)) return false;
+        }
+    }
+    return true;
+}
+
 /// Places `id` in column `c` by halving its tallest unfolded pane, when
 /// that leaves both their rows; false, and `id` in no column, when not.
 pub fn splitTallest(p: *Pardes, c: usize, id: usize) bool {