Initial Commit

packages/media/audio/audio-controllers/tests/purity.test.ts

@@ -0,0 +1,56 @@
+import { existsSync, readdirSync, readFileSync, statSync } from "node:fs";
+import { join } from "node:path";
+import { describe, expect, it } from "@suaveplan/testing/runner";
+
+const PKG_DIR = join(__dirname, "..");
+const DIST_DIR = join(PKG_DIR, "dist");
+
+function walk(dir: string, out: string[] = []): string[] {
+    if (!existsSync(dir)) return out;
+    for (const name of readdirSync(dir)) {
+        const p = join(dir, name);
+        const s = statSync(p);
+        if (s.isDirectory()) walk(p, out);
+        else if (/\.(js|mjs|cjs)$/.test(p)) out.push(p);
+    }
+    return out;
+}
+
+describe("purity", () => {
+    it("dist references no Node globals", { timeout: 30_000 }, () => {
+        if (!existsSync(DIST_DIR)) {
+            // dist will exist after build; skip purity if not yet built so the
+            // test suite can still run on a fresh clone.
+            expect(true).toBe(true);
+            return;
+        }
+        const offenders: string[] = [];
+        for (const file of walk(DIST_DIR)) {
+            const src = readFileSync(file, "utf8");
+            if (/\bnode:[a-z]+\b/.test(src)) offenders.push(`${file}: node:*`);
+            if (/\bprocess\.(env|cwd|platform)\b/.test(src))
+                offenders.push(`${file}: process`);
+            if (/\bBuffer\.from\b/.test(src)) offenders.push(`${file}: Buffer`);
+        }
+        expect(offenders).toEqual([]);
+    });
+
+    it("importing the package mutates no global state", {
+        timeout: 5000,
+    }, async () => {
+        const filter = (keys: string[]): string[] =>
+            keys
+                .filter(
+                    (k) =>
+                        !k.startsWith("__zod") &&
+                        !k.startsWith("__vitest") &&
+                        !k.startsWith("__VITEST")
+                )
+                .sort();
+        const beforeKeys = filter(Object.keys(globalThis));
+        const mod = await import("../src/index.js");
+        expect(mod.MidiControllerPlugin).toBeDefined();
+        const afterKeys = filter(Object.keys(globalThis));
+        expect(afterKeys).toEqual(beforeKeys);
+    });
+});