test(server): reproduce heap exhaustion in overlapping directory searches

packages/server/src/utils/directory-suggestions-memory.local.e2e.test.ts

@@ -0,0 +1,55 @@
+import { spawn } from "node:child_process";
+import { fileURLToPath } from "node:url";
+import { expect, it } from "vitest";
+
+// Opt-in reproduction: prepare the directory tree with scripts/repro-directory-search-memory.py,
+// then pass its location as PASEO_REPRO_SEARCH_ROOT. This exercises real filesystem calls.
+it.skipIf(!process.env.PASEO_REPRO_SEARCH_ROOT)(
+  "finishes overlapping directory searches without exhausting the Node heap",
+  async () => {
+    const modulePath = fileURLToPath(new URL("./directory-suggestions.ts", import.meta.url));
+    const source = `
+      const { searchDirectoryEntries } = await import(${JSON.stringify(modulePath)});
+      const query = "zzzzzzzzzzzzzz";
+      await Promise.all(Array.from({ length: query.length }, (_, index) =>
+        searchDirectoryEntries({
+          root: process.env.PASEO_REPRO_SEARCH_ROOT,
+          query: query.slice(0, index + 1),
+          pathFormat: "absolute",
+          includeFiles: false,
+          includeDirectories: true,
+          pathQueryPolicy: "rooted",
+          rootAliases: ["~"],
+          blankQueryBehavior: "none",
+          confidentResultScanThreshold: 5000,
+          limit: 30,
+        })
+      ));
+    `;
+    const result = await new Promise<{
+      code: number | null;
+      signal: string | null;
+      stderr: string;
+    }>((resolve, reject) => {
+      const child = spawn(
+        process.execPath,
+        ["--import", "tsx", "--input-type=module", "--eval", source],
+        {
+          stdio: ["ignore", "ignore", "pipe"],
+          env: process.env,
+        },
+      );
+      let stderr = "";
+      child.stderr.setEncoding("utf8");
+      child.stderr.on("data", (data: string) => {
+        stderr += data;
+      });
+      child.on("error", reject);
+      child.on("close", (code, signal) => resolve({ code, signal, stderr }));
+    });
+    expect(result.stderr).not.toContain("JavaScript heap out of memory");
+    expect(result.signal).toBeNull();
+    expect(result.code).toBe(0);
+  },
+  120_000,
+);

scripts/repro-directory-search-memory.py

@@ -0,0 +1,25 @@
+"""Create the real directory tree for the opt-in directory-search memory regression test.
+
+Run from the checkout root, then run:
+PASEO_REPRO_SEARCH_ROOT="$PWD/.diagnose-4879/home" npm exec --workspace=@getpaseo/server -- vitest run src/utils/directory-suggestions-memory.local.e2e.test.ts
+The fixture needs approximately 6 GB of disk space. No heap limit or delay is injected.
+"""
+import os
+import time
+
+root = os.path.join(os.getcwd(), ".diagnose-4879", "home")
+os.makedirs(root, exist_ok=True)
+start = time.monotonic()
+for branch_index in range(100):
+    branch = os.path.join(root, f"repos-{branch_index:03}")
+    os.makedirs(branch, exist_ok=True)
+    for package_index in range(140):
+        package = os.path.join(branch, f"packages-{package_index:03}")
+        os.makedirs(package, exist_ok=True)
+        for component_index in range(100):
+            os.makedirs(os.path.join(package, f"component-{component_index:03}"), exist_ok=True)
+    if branch_index % 10 == 9:
+        print(f"{branch_index + 1} branches built in {time.monotonic() - start:.1f}s", flush=True)
+for name in ["ai-credential-refresh", "ai-engineer-reference", "ai-tevv", "gmail-local-sync"]:
+    os.makedirs(os.path.join(root, "workspace", "projects", name), exist_ok=True)
+print("Created 1,414,106 directories", flush=True)