feat: vendor permission system source

pi-permission-system/test/helpers/tmp-fixture.ts

@@ -0,0 +1,76 @@
+import {
+  mkdirSync,
+  mkdtempSync,
+  rmSync,
+  symlinkSync,
+  writeFileSync,
+} from "node:fs";
+import { tmpdir } from "node:os";
+import { dirname, join } from "node:path";
+
+/**
+ * Real-filesystem fixtures for tests that must exercise filesystem *state*
+ * rather than lexical path logic — existence probes (`PathNormalizer.entryExists`)
+ * and symlink resolution (`canonicalizePath`).
+ *
+ * Every directory created is registered for cleanup; call {@link TmpFixture.cleanup}
+ * from an `afterEach`. Mirrors the `{ …, cleanup }` shape of `manager-harness.ts`.
+ */
+export interface TmpFixture {
+  /** Create a registered temp directory and return its absolute path. */
+  dir(prefix?: string): string;
+  /**
+   * Write a file under `parent` (creating intermediate directories) and return
+   * its absolute path. `name` may contain separators (`sub/file.txt`).
+   */
+  file(parent: string, name: string, content?: string): string;
+  /** Create a directory under `parent` and return its absolute path. */
+  subdir(parent: string, name: string): string;
+  /**
+   * Create a symlink at `parent/name` pointing at `target`, and return the link's
+   * absolute path. `target` need not exist — pass a nonexistent path to build a
+   * dangling symlink.
+   */
+  symlink(parent: string, name: string, target: string): string;
+  /** Remove every directory this fixture created. */
+  cleanup(): void;
+}
+
+export function createTmpFixture(): TmpFixture {
+  const roots: string[] = [];
+
+  return {
+    dir(prefix = "pi-perm-") {
+      const created = mkdtempSync(join(tmpdir(), prefix));
+      roots.push(created);
+      return created;
+    },
+
+    file(parent, name, content = "") {
+      const target = join(parent, name);
+      mkdirSync(dirname(target), { recursive: true });
+      writeFileSync(target, content);
+      return target;
+    },
+
+    subdir(parent, name) {
+      const target = join(parent, name);
+      mkdirSync(target, { recursive: true });
+      return target;
+    },
+
+    symlink(parent, name, target) {
+      const link = join(parent, name);
+      mkdirSync(dirname(link), { recursive: true });
+      symlinkSync(target, link);
+      return link;
+    },
+
+    cleanup() {
+      while (roots.length > 0) {
+        const root = roots.pop();
+        if (root) rmSync(root, { recursive: true, force: true });
+      }
+    },
+  };
+}