fix(stacked): stacked panes can't resize status-bar (#4051)

* fix(typo): fix a typo in error message

* fix(typo): fix typo in Tip #6

* fix(logging): silence filesystem error

This `Option` chain already ends with `.unwrap_or_else(Default::default)`
so it's clearly expected that prior operations in the chain may fail. I
didn't have the default `layout_dir` on my computer, and it would fill my
logfile with unhelpful spam — on every pane creation, resize, etc.

* fix(stacked): stacked panes can't resize status-bar

* fix(e2e): race in multiple users test

---------

Co-authored-by: Aram Drevekenin <aram@poor.dev>

2 files changed, 30 insertions, 2 deletions

diff --git a/zellij-server/src/panes/tiled_panes/pane_resizer.rs b/zellij-server/src/panes/tiled_panes/pane_resizer.rs
index 24d5df4f..506481d4 100644
--- a/zellij-server/src/panes/tiled_panes/pane_resizer.rs
+++ b/zellij-server/src/panes/tiled_panes/pane_resizer.rs
@@ -54,7 +54,10 @@ impl<'a> PaneResizer<'a> {
         let spans = self
             .discretize_spans(grid, space)
             .map_err(|err| anyhow!("{}", err))?;
-        self.apply_spans(spans)?;
+
+        if self.is_layout_valid(&spans) {
+            self.apply_spans(spans)?;
+        }
         Ok(())
     }
 
@@ -128,6 +131,31 @@ impl<'a> PaneResizer<'a> {
         Ok(grid.into_iter().flatten().collect())
     }
 
+    // HACK: This whole function is a bit of a hack — it's here to stop us from breaking the layout if we've been given
+    // a bad state to start with. If this function returns false, nothing is resized.
+    fn is_layout_valid(&self, spans: &[Span]) -> bool {
+        // If pane stacks are too tall to fit on the screen, abandon ship before the status bar gets caught up in
+        // any erroneous resizing...
+        for span in spans {
+            let pane_is_stacked = self
+                .panes
+                .borrow()
+                .get(&span.pid)
+                .unwrap()
+                .current_geom()
+                .is_stacked();
+            if pane_is_stacked && span.direction == SplitDirection::Vertical {
+                let min_stack_height = StackedPanes::new(self.panes.clone())
+                    .min_stack_height(&span.pid)
+                    .unwrap();
+                if span.size.as_usize() < min_stack_height {
+                    return false;
+                }
+            }
+        }
+        true
+    }
+
     fn apply_spans(&mut self, spans: Vec<Span>) -> Result<()> {
         let err_context = || format!("Failed to apply spans");
         let mut geoms_changed = false;
diff --git a/zellij-server/src/panes/tiled_panes/stacked_panes.rs b/zellij-server/src/panes/tiled_panes/stacked_panes.rs
index a8640489..8044b0b0 100644
--- a/zellij-server/src/panes/tiled_panes/stacked_panes.rs
+++ b/zellij-server/src/panes/tiled_panes/stacked_panes.rs
@@ -309,7 +309,7 @@ impl<'a> StackedPanes<'a> {
         Ok(())
     }
     fn pane_is_one_liner(&self, id: &PaneId) -> Result<bool> {
-        let err_context = || format!("Cannot determin if pane is one liner or not");
+        let err_context = || format!("Cannot determine if pane is one liner or not");
         let panes = self.panes.borrow();
         let pane_to_close = panes.get(id).with_context(err_context)?;
         Ok(pane_to_close.position_and_size().rows.is_fixed())