Validate and deduplicate custom difficulty presets

tests/difficulty-presets.test.ts

@@ -0,0 +1,86 @@
+import assert from "node:assert/strict";
+import { test } from "node:test";
+import { customDifficultySchema } from "../shared/protocol";
+import { mergeDifficultyPresets } from "../shared/difficulty-presets";
+
+const rules = { seconds: 90, zoom: true };
+test("difficulty names accept normal text and count Unicode characters consistently with PostgreSQL", () => {
+  for (const name of [
+    "Normal",
+    "Speed 90",
+    "Тест",
+    "中文",
+    "😎😎",
+    "😎".repeat(40),
+    "a".repeat(40),
+    "a\\b",
+  ])
+    assert.equal(
+      customDifficultySchema.safeParse({ name, ...rules }).success,
+      true,
+      name,
+    );
+  assert.equal(
+    customDifficultySchema.parse({ name: "  My challenge  ", ...rules }).name,
+    "My challenge",
+  );
+  for (const name of [
+    "",
+    "a",
+    "😎",
+    "a".repeat(41),
+    "😎".repeat(41),
+    "x\nname",
+    "x\u0085name",
+    "x\u202ename",
+    "x\u2066name",
+  ])
+    assert.equal(
+      customDifficultySchema.safeParse({ name, ...rules }).success,
+      false,
+    );
+});
+
+test("difficulty rules enforce their supported range and strict request shape", () => {
+  for (const seconds of [15, 90, 600])
+    assert.equal(
+      customDifficultySchema.safeParse({ name: "Fixture", ...rules, seconds })
+        .success,
+      true,
+    );
+  for (const seconds of [0, 14, 16, 601, 15.5, NaN, Infinity, "90"])
+    assert.equal(
+      customDifficultySchema.safeParse({ name: "Fixture", ...rules, seconds })
+        .success,
+      false,
+    );
+  assert.equal(
+    customDifficultySchema.safeParse({
+      name: "Fixture",
+      ...rules,
+      owner: "forged",
+    }).success,
+    false,
+  );
+});
+
+test("a delayed preset listing cannot erase a newly saved preset or duplicate it", async () => {
+  const old = { id: "old", name: "Old", ...rules };
+  const saved = { id: "saved", name: "New", ...rules };
+  let release!: (presets: (typeof old)[]) => void;
+  const response = new Promise<(typeof old)[]>((resolve) => {
+    release = resolve;
+  });
+  let presets = [old];
+  const loading = response.then((snapshot) => {
+    presets = mergeDifficultyPresets(presets, snapshot);
+  });
+  presets = mergeDifficultyPresets(presets, [saved]);
+  release([old]);
+  await loading;
+  assert.deepEqual(
+    presets.map((p) => p.id),
+    ["saved", "old"],
+  );
+  assert.equal(mergeDifficultyPresets(presets, [saved]).length, 2);
+});