test(fixtures): add per-file size-budget guard (phase 1)

tests/unit/fixtures/fixture-budget.test.ts

@@ -0,0 +1,42 @@
+import { readdirSync, statSync } from "node:fs";
+import { dirname, extname, join } from "node:path";
+import { fileURLToPath } from "node:url";
+import { describe, expect, it } from "vitest";
+
+const ROOT = join(dirname(fileURLToPath(import.meta.url)), "../../fixtures");
+
+// Per-extension MB ceilings. RAW/codec containers get headroom; everything else is tight.
+const RAW = new Set([".arw", ".nef", ".rw2", ".orf", ".cr2", ".dng", ".exr", ".psd"]);
+function capMb(file: string): number {
+  const ext = extname(file).toLowerCase();
+  if (RAW.has(ext)) return 24;
+  if ([".mp4", ".mov", ".webm", ".mkv", ".avi"].includes(ext)) return 8;
+  if ([".jpg", ".jpeg", ".png", ".webp", ".heic", ".heif", ".avif", ".gif"].includes(ext)) return 8;
+  if ([".wav", ".mp3", ".flac", ".ogg", ".m4a", ".aac", ".opus"].includes(ext)) return 4;
+  if ([".pdf", ".docx", ".xlsx", ".pptx", ".epub", ".odt"].includes(ext)) return 4;
+  return 1;
+}
+
+function walk(dir: string): string[] {
+  return readdirSync(dir, { withFileTypes: true }).flatMap((e) => {
+    const full = join(dir, e.name);
+    if (e.isDirectory()) return walk(full);
+    if (
+      e.name === "index.ts" ||
+      e.name === ".gitkeep" ||
+      e.name.endsWith(".md") ||
+      e.name.endsWith(".json")
+    )
+      return [];
+    return [full];
+  });
+}
+
+describe("fixture size budget", () => {
+  const files = walk(ROOT);
+  it("finds fixtures", () => expect(files.length).toBeGreaterThan(100));
+  it.each(files)("within budget: %s", (f) => {
+    const mb = statSync(f).size / (1024 * 1024);
+    expect(mb, `${f} is ${mb.toFixed(1)}MB > ${capMb(f)}MB cap`).toBeLessThanOrEqual(capMb(f));
+  });
+});