feat: add CLI regression tests

test/cli.test.js

@@ -0,0 +1,82 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import { mkdir, mkdtemp, rm, writeFile } from "node:fs/promises";
+import os from "node:os";
+import path from "node:path";
+import { run } from "../src/cli.js";
+
+async function fixture() {
+  const root = await mkdtemp(path.join(os.tmpdir(), "cache-compass-cli-"));
+  const cache = path.join(root, "web", "node_modules", ".cache");
+  await mkdir(cache, { recursive: true });
+  await writeFile(path.join(cache, "bundle.bin"), Buffer.alloc(128));
+  return { root, cache };
+}
+
+function createIo() {
+  const stdout = [];
+  const stderr = [];
+  return {
+    io: {
+      log(message) {
+        stdout.push(message);
+      },
+      error(message) {
+        stderr.push(message);
+      },
+    },
+    stdout,
+    stderr,
+  };
+}
+
+test("run renders dry-run JSON reports for matching caches", async (t) => {
+  const { root } = await fixture();
+  t.after(() => rm(root, { recursive: true, force: true }));
+  const { io, stdout, stderr } = createIo();
+
+  const exitCode = await run([root, "--format", "json"], io);
+  const report = JSON.parse(stdout[0]);
+
+  assert.equal(exitCode, 0);
+  assert.equal(stderr.length, 0);
+  assert.equal(report.mode, "dry-run");
+  assert.equal(report.summary.directories, 1);
+  assert.equal(report.summary.bytes, 128);
+  assert.deepEqual(report.caches.map((cache) => cache.path), [
+    path.join("web", "node_modules", ".cache"),
+  ]);
+  assert.deepEqual(report.removals, []);
+});
+
+test("run removes matched caches when apply is enabled", async (t) => {
+  const { root } = await fixture();
+  t.after(() => rm(root, { recursive: true, force: true }));
+  const { io, stdout, stderr } = createIo();
+
+  const exitCode = await run([root, "--apply", "--format", "json"], io);
+  const report = JSON.parse(stdout[0]);
+
+  assert.equal(exitCode, 0);
+  assert.equal(stderr.length, 0);
+  assert.deepEqual(report.removals, [
+    {
+      path: path.join("web", "node_modules", ".cache"),
+      status: "removed",
+    },
+  ]);
+
+  const after = await run([root, "--format", "json"], createIo().io);
+  assert.equal(after, 0);
+});
+
+test("run returns usage errors without scanning", async () => {
+  const { io, stdout, stderr } = createIo();
+
+  const exitCode = await run(["--format", "xml"], io);
+
+  assert.equal(exitCode, 2);
+  assert.equal(stdout.length, 0);
+  assert.match(stderr[0], /Unsupported format: xml/);
+  assert.match(stderr[1], /--help/);
+});