feat: implement benchmarks using mitata (#496)

* feat: implement benchmarks using mitata

* chore: add changeset

* chore: add performance benchmarks using mitata

- Add benchmarking infrastructure in workspaces/js-x-ray/benchmark

- Use Node.js type stripping (requires Node >= 22)

* chore: consolidate benchmarks into index.ts and move docs to root README

* chore: use import.meta.dirname & move benchmark docs to end of README

* chore: remove redundant run options in benchmarks

* chore: implement file size thresholds for benchmark selection

* chore: benchmark all files in size categories

* Update README.md

Co-authored-by: Clement Gombauld <[email protected]>

---------

Co-authored-by: Clement Gombauld <[email protected]>

Author: 7amed3li

.changeset/benchmark-mitata.md

@@ -0,0 +1,5 @@
+---
+"@nodesecure/js-x-ray": patch
+---
+
+feat: add performance benchmarks using mitata

README.md

@@ -115,6 +115,7 @@ Alternatively, you can use `EntryFilesAnalyser` directly for multi-file analysis
 - [EntryFilesAnalyser](./workspaces/js-x-ray/docs/EntryFilesAnalyser.md)
 - [CollectableSet](./workspaces/js-x-ray/docs/CollectableSet.md)
 
+
 ## Warnings
 
 ```ts
@@ -254,6 +255,14 @@ $ npm i @nodesecure/estree-ast-util
 $ yarn add @nodesecure/estree-ast-util
 ```
 
+## Benchmarks
+
+The performance of js-x-ray is measured and tracked using [mitata](https://github.com/evanwashere/mitata).
+
+To run the benchmarks:
+1. Navigate to `workspaces/js-x-ray`.
+2. Run `npm run bench`.
+
 ## Contributors ✨
 
 <!-- ALL-CONTRIBUTORS-BADGE:START - Do not remove or modify this section -->

workspaces/js-x-ray/benchmark/index.ts

@@ -0,0 +1,85 @@
+
+// Import Node.js Dependencies
+import { readFileSync, readdirSync } from "node:fs";
+import { join, resolve } from "node:path";
+
+// Import Third-party Dependencies
+import { run, bench, group } from "mitata";
+
+// Import Internal Dependencies
+import { AstAnalyser } from "../src/index.ts";
+
+// Constants
+const EXAMPLES_DIR = resolve(import.meta.dirname, "../examples");
+
+const KILOBYTE = 1024;
+const SMALL_THRESHOLD = 10 * KILOBYTE;
+const LARGE_THRESHOLD = 50 * KILOBYTE;
+
+interface Fixture {
+  name: string;
+  content: string;
+  size: number;
+}
+
+function loadFixtures(): Fixture[] {
+  const files = readdirSync(EXAMPLES_DIR);
+
+  return files.map((file) => {
+    const path = join(EXAMPLES_DIR, file);
+    const content = readFileSync(path, "utf-8");
+
+    return {
+      name: file,
+      content,
+      size: content.length
+    };
+  });
+}
+
+const fixtures = loadFixtures();
+const analyser = new AstAnalyser();
+
+function formatFileSize(fixture: Fixture): string {
+  return `${fixture.name} - ${(fixture.size / 1024).toFixed(2)}KB`;
+}
+
+group("AstAnalyser.analyse()", () => {
+  const sortedFixtures = [...fixtures].sort((a, b) => a.size - b.size);
+
+  const smallFixtures = sortedFixtures.filter((f) => f.size < SMALL_THRESHOLD);
+  const mediumFixtures = sortedFixtures.filter((f) => f.size >= SMALL_THRESHOLD && f.size < LARGE_THRESHOLD);
+  const largeFixtures = sortedFixtures.filter((f) => f.size >= LARGE_THRESHOLD);
+
+  for (const fixture of smallFixtures) {
+    bench(`Small File (${formatFileSize(fixture)})`, () => {
+      analyser.analyse(fixture.content);
+    });
+  }
+
+  for (const fixture of mediumFixtures) {
+    bench(`Medium File (${formatFileSize(fixture)})`, () => {
+      analyser.analyse(fixture.content);
+    });
+  }
+
+  for (const fixture of largeFixtures) {
+    bench(`Large File (${formatFileSize(fixture)})`, () => {
+      analyser.analyse(fixture.content);
+    })
+      // Large files might need GC between runs to be stable
+      .gc("inner");
+  }
+});
+
+group("Obfuscated Code Analysis", () => {
+  const obfuscated = fixtures.filter((f) => f.name.includes("obfuscate") || f.name.includes("jscrush"));
+
+  for (const fixture of obfuscated) {
+    bench(`${fixture.name}`, () => {
+      analyser.analyse(fixture.content);
+    });
+  }
+});
+
+await run();

workspaces/js-x-ray/package.json

@@ -21,7 +21,8 @@
     "prepublishOnly": "npm run build",
     "build": "tsc",
     "test-only": "node --test-reporter=spec --test ./test/**/*.spec.ts",
-    "test": "c8 --all --src ./src -r html npm run test-only"
+    "test": "c8 --all --src ./src -r html npm run test-only",
+    "bench": "node --expose-gc --experimental-strip-types ./benchmark/index.ts"
   },
   "publishConfig": {
     "registry": "https://registry.npmjs.org",
@@ -63,6 +64,7 @@
     "ts-pattern": "^5.0.6"
   },
   "devDependencies": {
-    "astring": "1.9.0"
+    "astring": "1.9.0",
+    "mitata": "1.0.34"
   }
 }