feat: simplify odometer result

.husky/commit-msg

@@ -0,0 +1,4 @@
+#!/bin/sh
+. "$(dirname "$0")/_/husky.sh"
+
+npx --no-install commitlint --edit "$1"

.husky/pre-commit

@@ -0,0 +1,4 @@
+#!/bin/sh
+. "$(dirname "$0")/_/husky.sh"
+
+npm run precommit

.husky/pre-push

@@ -0,0 +1,4 @@
+#!/bin/sh
+. "$(dirname "$0")/_/husky.sh"
+
+npm run prepush

src/odometer/Odometer.ts

@@ -8,7 +8,7 @@ export class Odometer<Context = unknown> {
   public getDifference(
     aSet: Intermediate<Context, Replacement<Context>>[],
     bSet: Intermediate<Context, Replacement<Context>>[],
-  ): OdometerStats<Context> {
+  ): OdometerStats<Context> | null {
     let minimalDistance = Number.POSITIVE_INFINITY;
     let aBest: Intermediate<Context, Replacement<Context>> | null = null;
     let bBest: Intermediate<Context, Replacement<Context>> | null = null;
@@ -29,6 +29,10 @@ export class Odometer<Context = unknown> {
       }
     }
 
+    if (aBest == null || bBest == null) {
+      return null;
+    }
+
     return {
       a: aBest,
       b: bBest,

src/odometer/OdometerStats.ts

@@ -2,7 +2,7 @@ import { Replacement } from '../multireplacer';
 import { Intermediate } from '../utils';
 
 export type OdometerStats<T> = {
-  a: Intermediate<T, Replacement<T>> | null;
-  b: Intermediate<T, Replacement<T>> | null;
+  a: Intermediate<T, Replacement<T>>;
+  b: Intermediate<T, Replacement<T>>;
   distance: number;
 };