Workaround maps with broken partitioning. #960

Let most of the tool work -- just no boundary adjustment. Selecting the
neighbourhood that's broken would also crash, except it has no polygon,
so it can't be selected!

apps/ltn/src/partition.rs

@@ -36,6 +36,7 @@ pub struct Partitioning {
     block_to_neighbourhood: BTreeMap<BlockID, NeighbourhoodID>,
 
     use_expensive_blockfinding: bool,
+    pub broken: bool,
 }
 
 #[derive(Clone, Serialize, Deserialize)]
@@ -68,6 +69,7 @@ impl Partitioning {
             block_to_neighbourhood: BTreeMap::new(),
 
             use_expensive_blockfinding: false,
+            broken: false,
         }
     }
 
@@ -143,6 +145,7 @@ impl Partitioning {
                 neighbourhood_id_counter,
                 block_to_neighbourhood: BTreeMap::new(),
                 use_expensive_blockfinding,
+                broken: false,
             };
 
             // TODO We could probably build this up as we go
@@ -159,10 +162,11 @@ impl Partitioning {
                         continue 'METHOD;
                     }
                     // This will break everything downstream, so bail out immediately
-                    panic!(
-                        "Block doesn't belong to any neighbourhood?! {:?}",
+                    error!(
+                        "Block still doesn't belong to any neighbourhood, even with expensive checks. Continuing without boundary adjustment. {:?}",
                         p.get_block(id).perimeter
                     );
+                    p.broken = true;
                 }
             }
 

apps/ltn/src/select_boundary.rs

@@ -5,7 +5,7 @@ use anyhow::Result;
 use geom::Polygon;
 use map_gui::tools::DrawSimpleRoadLabels;
 use widgetry::mapspace::{World, WorldOutcome};
-use widgetry::tools::Lasso;
+use widgetry::tools::{Lasso, PopupMsg};
 use widgetry::{
     Drawable, EventCtx, GeomBatch, GfxCtx, Key, Line, Outcome, Panel, State, Text, TextExt, Widget,
 };
@@ -40,6 +40,17 @@ impl SelectBoundary {
         app: &mut App,
         id: NeighbourhoodID,
     ) -> Box<dyn State<App>> {
+        if app.session.partitioning.broken {
+            return PopupMsg::new_state(
+                ctx,
+                "Error",
+                vec![
+                    "Sorry, you can't adjust any boundaries on this map.",
+                    "This is a known problem without any workaround yet.",
+                ],
+            );
+        }
+
         // Make sure we clear this state if we ever modify neighbourhood boundaries
         if let EditMode::Shortcuts(ref mut maybe_focus) = app.session.edit_mode {
             *maybe_focus = None;