fix dict

engine/lib/Dictionary.test.ts

@@ -0,0 +1,33 @@
+import { expect, test } from "vitest";
+import {
+	createDictionary,
+	type Dictionary,
+	deleteEntrySave,
+	forEntry,
+	getEntry,
+	setEntrySave,
+} from "./Dictionary.ts";
+
+test("Dictionary", () => {
+	const dict: Dictionary<string, number> = createDictionary([
+		["a", 1],
+		["b", 2],
+		["c", 3],
+	]);
+	setEntrySave(dict, "foo", 42);
+	setEntrySave(dict, "bar", 0);
+	deleteEntrySave(dict, "bar");
+
+	console.table(dict.entries);
+	console.table(dict.indices);
+
+	expect(getEntry(dict, "foo")).toBe(42);
+	expect(getEntry(dict, "bar")).toBe(undefined);
+	expect(dict.indices.size).toBe(dict.entries.length);
+
+	let sum = 0;
+	forEntry(dict, (value) => {
+		sum += value;
+	});
+	expect(sum).toBe(48);
+});

engine/lib/Dictionary.ts

@@ -6,10 +6,15 @@ export type Dictionary<K, V> = {
 	setQueue: Array<[K, V]>;
 };
 
-export function createDictionary<K, V>(): Dictionary<K, V> {
+export function createDictionary<K, V>(
+	iterable?: Iterable<[K, V]>,
+): Dictionary<K, V> {
+	const entries = iterable ? [...iterable] : [];
+	const indices = new Map(entries.map(([k], i) => [k, i]));
+
 	return {
-		entries: [],
-		indices: new Map(),
+		entries,
+		indices,
 		isIterating: false,
 		deleteQueue: [],
 		setQueue: [],
@@ -46,8 +51,8 @@ export function setEntry<K, V>(
 ): void {
 	const index = dict.indices.get(key);
 	if (index === undefined) {
-		dict.entries.push([key, value]);
 		dict.indices.set(key, dict.entries.length);
+		dict.entries.push([key, value]);
 	} else {
 		dict.entries[index][1] = value;
 	}