Merge pull request #51 from crhallberg/closest-fix

crhallberg · web-flow · commit e39d99468037 · 2021-03-02T15:11:20.000-05:00
Fix closest search infinite loop
diff --git a/quadtree.js b/quadtree.js
@@ -307,6 +307,13 @@ class QuadTree {
       );
       // Together, a circle that encompasses the whole QuadTree
       maxDistance = outerReach + pointDistance;
+    } else {
+      // Make sure the largest search (maxDistance) contains enough points
+      let maxOuter = new Circle(point.x, point.y, maxDistance);
+      let maxDistanceTest = this.query(maxOuter);
+      if (maxDistanceTest.length < count) {
+        return maxDistanceTest;
+      }
     }
 
     // Binary search with Circle queries
diff --git a/test/quadtree.spec.js b/test/quadtree.spec.js
@@ -355,6 +355,16 @@ describe('QuadTree', () => {
       expect(found).to.have.length(1);
       expect(found).to.contain(points[0]);
     });
+    // Supplied maxDistance
+    it('limits search to maxDistance', () => {
+      found = quadtree.closest(new Point(0, 0), 3, 25);
+      expect(found).to.have.length(1);
+      expect(found).to.contain(points[0]);
+    });
+    it('gracefully fails search if nothing within maxDistance', () => {
+      found = quadtree.closest(new Point(-100, 0), 3, 25);
+      expect(found).to.have.length(0);
+    });
   });
   describe('length', () => {
     let quadtree;
