feat(plan): add core logic and exit_plan_mode tool definition (#18110)

2026-04-21 18:44:30 -07:00 · 2026-02-02 22:30:03 -05:00
parent 01e33465bd
commit ed26ea49e9
13 changed files with 981 additions and 2 deletions
@@ -0,0 +1,69 @@
+/**
+ * @license
+ * Copyright 2026 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import path from 'node:path';
+import { isEmpty, fileExists } from './fileUtils.js';
+import { isSubpath, resolveToRealPath } from './paths.js';
+
+/**
+ * Standard error messages for the plan approval workflow.
+ * Shared between backend tools and CLI UI for consistency.
+ */
+export const PlanErrorMessages = {
+  PATH_ACCESS_DENIED:
+    'Access denied: plan path must be within the designated plans directory.',
+  FILE_NOT_FOUND: (path: string) =>
+    `Plan file does not exist: ${path}. You must create the plan file before requesting approval.`,
+  FILE_EMPTY:
+    'Plan file is empty. You must write content to the plan file before requesting approval.',
+  READ_FAILURE: (detail: string) => `Failed to read plan file: ${detail}`,
+} as const;
+
+/**
+ * Validates a plan file path for safety (traversal) and existence.
+ * @param planPath The untrusted path to the plan file.
+ * @param plansDir The authorized project plans directory.
+ * @param targetDir The current working directory (project root).
+ * @returns An error message if validation fails, or null if successful.
+ */
+export async function validatePlanPath(
+  planPath: string,
+  plansDir: string,
+  targetDir: string,
+): Promise<string | null> {
+  const resolvedPath = path.resolve(targetDir, planPath);
+  const realPath = resolveToRealPath(resolvedPath);
+  const realPlansDir = resolveToRealPath(plansDir);
+
+  if (!isSubpath(realPlansDir, realPath)) {
+    return PlanErrorMessages.PATH_ACCESS_DENIED;
+  }
+
+  if (!(await fileExists(resolvedPath))) {
+    return PlanErrorMessages.FILE_NOT_FOUND(planPath);
+  }
+
+  return null;
+}
+
+/**
+ * Validates that a plan file has non-empty content.
+ * @param planPath The path to the plan file.
+ * @returns An error message if the file is empty or unreadable, or null if successful.
+ */
+export async function validatePlanContent(
+  planPath: string,
+): Promise<string | null> {
+  try {
+    if (await isEmpty(planPath)) {
+      return PlanErrorMessages.FILE_EMPTY;
+    }
+    return null;
+  } catch (err) {
+    const message = err instanceof Error ? err.message : String(err);
+    return PlanErrorMessages.READ_FAILURE(message);
+  }
+}