diff --git a/deno.jsonc b/deno.jsonc
index c18304c..07a2638 100644
--- a/deno.jsonc
+++ b/deno.jsonc
@@ -2,8 +2,8 @@
   "$schema": "https://deno.land/x/deno/cli/schemas/config-file.v1.json",
   "tasks": {
     "check": "deno fmt --check && deno lint && deno check **/*.ts **/*.js",
-    "test": "rm -rf coverage && deno test -A --coverage --parallel --shuffle && deno coverage coverage --html && deno coverage coverage --lcov --output=coverage/lcov.info --exclude='test/**/*'",
-    "ci": "deno test -A --coverage && deno coverage coverage --lcov --output=coverage/lcov.info",
+    "test": "rm -rf coverage && deno test -A --coverage --parallel --shuffle && deno coverage coverage --html --exclude='test/**/*' --exclude=day.ts  && deno coverage coverage --lcov --output=coverage/lcov.info",
+    "ci": "deno test -A --coverage && deno coverage coverage --lcov --output=coverage/lcov.info --exclude='test/**/*' --exclude=day.ts",
     "update": "deno run -A jsr:@molt/cli --dry-run",
     "docs": "deno doc --html --name=AdventOfCode2024 lib/*.ts",
     "bench": "deno bench -A day.ts -- -b"
diff --git a/lib/rect.ts b/lib/rect.ts
index 730cac0..6cfac10 100644
--- a/lib/rect.ts
+++ b/lib/rect.ts
@@ -358,7 +358,7 @@ export class Rect<T = string> {
   with(xp: PointLike | number, yp: number | T, val?: T): Rect<T> {
     const [x, y, v] = (typeof xp === 'number')
       ? [xp, yp as number, val as T]
-      : [xp.x, xp.y, val!];
+      : [xp.x, xp.y, yp as T];
     const r = this.copy();
     r.set(x, y, v);
     return r;
@@ -443,6 +443,10 @@ export class Rect<T = string> {
   }
 }
 
+/**
+ * Rectangle that wraps around so that the top is below the bottom and right
+ * column is left of 0.
+ */
 export class InfiniteRect<T> extends Rect<T> {
   max: Point;
   min: Point;
@@ -471,10 +475,10 @@ export class InfiniteRect<T> extends Rect<T> {
     const col = mod(x, this.width);
     const line = mod(y, this.height);
 
-    this.min.x = Math.min(this.min.x, col);
-    this.min.y = Math.min(this.min.y, line);
-    this.max.x = Math.max(this.max.x, col);
-    this.max.y = Math.max(this.max.y, line);
+    this.min.x = Math.min(this.min.x, x);
+    this.min.y = Math.min(this.min.y, y);
+    this.max.x = Math.max(this.max.x, x);
+    this.max.y = Math.max(this.max.y, y);
 
     super.set(col, line, val!);
   }
diff --git a/lib/test/counter.test.ts b/lib/test/counter.test.ts
index 3dedb6f..76e3ea9 100644
--- a/lib/test/counter.test.ts
+++ b/lib/test/counter.test.ts
@@ -9,6 +9,7 @@ Deno.test('Counter', () => {
   c.add(1, 2); // 1
   assertEquals(c.get(1, 2), 1);
   assertEquals(c.get(33), 0);
+  assertEquals(c.values(), [1]);
   c.add(1, 2); // 2
   c.add(3, 4); // 1
   assertEquals(c.keys(), ['1,2', '3,4']);
diff --git a/lib/test/rect.test.ts b/lib/test/rect.test.ts
index 46c3958..91a1629 100644
--- a/lib/test/rect.test.ts
+++ b/lib/test/rect.test.ts
@@ -1,4 +1,4 @@
-import { Point, Rect } from '../rect.ts';
+import { Dir, InfiniteRect, Point, Rect } from '../rect.ts';
 
 import {
   assert,
@@ -17,6 +17,10 @@ Deno.test('Point', async (t) => {
     assert(p2.equals({ x: 3, y: -1 }));
     const p3 = p.stretch(2);
     assertEquals(p3, new Point(6, 8));
+    assertEquals(p.inDir(Dir.E), new Point(4, 4));
+    assertEquals(p.inDir(Dir.W), new Point(2, 4));
+    assertEquals(p.inDir(Dir.N), new Point(3, 3));
+    assertEquals(p.inDir(Dir.S), new Point(3, 5));
   });
 
   await t.step('distances', () => {
@@ -31,6 +35,29 @@ Deno.test('Point', async (t) => {
     assertEquals(p.toString(), '9,8');
     assertEquals(Deno.inspect(p), '9,8');
   });
+
+  await t.step('neighbors', () => {
+    const p = new Point(6, 8);
+    assertEquals(p.cardinal(), [
+      new Point(7, 8),
+      new Point(6, 9),
+      new Point(5, 8),
+      new Point(6, 7),
+    ]);
+    assertEquals(p.cardinal(Rect.ofSize(8, 8, '')), [
+      new Point(6, 7),
+    ]);
+  });
+
+  await t.step('sort', () => {
+    const points = [new Point(2, 3), new Point(2, 1), new Point(1, 2)];
+    points.sort(Point.sort);
+    assertEquals(points, [
+      new Point(1, 2),
+      new Point(2, 1),
+      new Point(2, 3),
+    ]);
+  });
 });
 
 Deno.test('Rect', async (t) => {
@@ -95,6 +122,8 @@ Deno.test('Rect', async (t) => {
     assertEquals(s.get(p), 'p');
     s.set({ x: 0, y: 0 }, 'q');
     assertEquals(s.get({ x: 0, y: 0 }), 'q');
+    const t = r.with(new Point(0, 0), 't');
+    assertEquals(Deno.inspect(t), 'tbc\ndef');
   });
 
   await t.step('toString', () => {
@@ -139,4 +168,39 @@ XdefX
 XXXXX`,
     );
   });
+
+  await t.step('map', () => {
+    const s = r.map(() => 'z');
+    assertEquals(Deno.inspect(s), 'zzz\nzzz');
+  });
+
+  await t.step('indexOf', () => {
+    const p = r.indexOf('e');
+    assertEquals(p, new Point(1, 1));
+    assertEquals(r.indexOf('z'), undefined);
+  });
+});
+
+Deno.test('InfinitRect', async (t) => {
+  await t.step('create', () => {
+    const ir = new InfiniteRect([[1, 2], [3, 4]]);
+    assertEquals(ir.min, new Point(0, 0));
+    assertEquals(ir.max, new Point(2, 2));
+    assert(ir.check(new Point(100, 1000)));
+    assertEquals(ir.get(new Point(3, 3)), 4);
+    ir.set(4, 4, 9);
+    assertEquals(ir.max.x, 4);
+    assertEquals(ir.max.y, 4);
+    ir.set(new Point(-1, 0), 8);
+    assertEquals(ir.min.x, -1);
+  });
+
+  await t.step('slice', () => {
+    const ir = new InfiniteRect([
+      'abc'.split(''),
+      'def'.split(''),
+    ]);
+    const s = ir.slice(new Point(0, 0), new Point(1, 1));
+    assertEquals(Deno.inspect(s), 'ab\nde');
+  });
 });
diff --git a/lib/utils.ts b/lib/utils.ts
index 017791a..4a1e056 100644
--- a/lib/utils.ts
+++ b/lib/utils.ts
@@ -1,5 +1,6 @@
 import { dirname, fromFileUrl, join } from '$std/path/mod.ts';
 import { TextLineStream } from '$std/streams/mod.ts';
+import { assert } from '$std/assert/mod.ts';
 import peggy from 'peggy';
 
 export interface MainArgs {
@@ -207,12 +208,8 @@ export function divmod<T extends number | bigint>(x: T, y: T): [T, T] {
     }
     return [q, r];
   }
-  if (typeof q === 'number') {
-    return [Math.floor(q) as T, r];
-  }
-
-  /* c8 ignore next */
-  throw new Error('Unreachable');
+  assert(typeof q === 'number');
+  return [Math.floor(q) as T, r];
 }
 
 export function gcd<T extends number | bigint>(...n: T[]): T {