fix(permissions): normalize Windows absolute file-rule matching (#973)

Co-authored-by: Letta <noreply@letta.com>

src/tests/permissions-checker.test.ts

@@ -272,6 +272,53 @@ test("Allow exact Bash command", () => {
   expect(result2.decision).toBe("ask"); // Doesn't match exact
 });
 
+test("Issue #969: legacy Windows Edit allow rule matches memory project file", () => {
+  const permissions: PermissionRules = {
+    allow: [
+      "Edit(/C:\\Users\\Aaron\\.letta\\agents\\agent-7dcc\\memory\\system\\project/**)",
+    ],
+    deny: [],
+    ask: [],
+  };
+
+  const result = checkPermission(
+    "Edit",
+    {
+      file_path:
+        "C:\\Users\\Aaron\\.letta\\agents\\agent-7dcc\\memory\\system\\project\\tech_stack.md",
+    },
+    permissions,
+    "C:\\Users\\Aaron\\repo",
+  );
+
+  expect(result.decision).toBe("allow");
+  expect(result.matchedRule).toBe(
+    "Edit(/C:\\Users\\Aaron\\.letta\\agents\\agent-7dcc\\memory\\system\\project/**)",
+  );
+});
+
+test("Issue #969 guardrail: Windows legacy Edit rule does not over-match sibling subtree", () => {
+  const permissions: PermissionRules = {
+    allow: [
+      "Edit(/C:\\Users\\Aaron\\.letta\\agents\\agent-7dcc\\memory\\system\\project/**)",
+    ],
+    deny: [],
+    ask: [],
+  };
+
+  const result = checkPermission(
+    "Edit",
+    {
+      file_path:
+        "C:\\Users\\Aaron\\.letta\\agents\\agent-7dcc\\memory\\system\\other\\x.md",
+    },
+    permissions,
+    "C:\\Users\\Aaron\\repo",
+  );
+
+  expect(result.decision).toBe("ask");
+});
+
 // ============================================================================
 // Ask Rule Tests
 // ============================================================================

src/tests/permissions-matcher.test.ts

@@ -349,3 +349,73 @@ test("File pattern: Windows absolute path in working directory", () => {
     ),
   ).toBe(true);
 });
+
+test("File pattern: Windows absolute variants are equivalent", () => {
+  const query =
+    "Edit(C:\\Users\\Aaron\\.letta\\agents\\agent-1\\memory\\system\\project\\tech_stack.md)";
+  const workingDir = "C:\\Users\\Aaron\\repo";
+
+  expect(
+    matchesFilePattern(
+      query,
+      "Edit(/C:/Users/Aaron/.letta/agents/agent-1/memory/system/project/**)",
+      workingDir,
+    ),
+  ).toBe(true);
+
+  expect(
+    matchesFilePattern(
+      query,
+      "Edit(//C:/Users/Aaron/.letta/agents/agent-1/memory/system/project/**)",
+      workingDir,
+    ),
+  ).toBe(true);
+
+  expect(
+    matchesFilePattern(
+      query,
+      "Edit(C:/Users/Aaron/.letta/agents/agent-1/memory/system/project/**)",
+      workingDir,
+    ),
+  ).toBe(true);
+});
+
+test("File pattern: Windows drive-letter matching is case-insensitive", () => {
+  const query = "Edit(c:\\users\\aaron\\repo\\src\\file.ts)";
+  const workingDir = "C:\\Users\\Aaron\\repo";
+
+  expect(
+    matchesFilePattern(query, "Edit(C:/Users/Aaron/repo/src/**)", workingDir),
+  ).toBe(true);
+});
+
+test("File pattern: UNC absolute path matches normalized UNC pattern", () => {
+  const query = "Edit(\\\\server\\share\\folder\\file.md)";
+  const workingDir = "C:\\Users\\Aaron\\repo";
+
+  expect(
+    matchesFilePattern(query, "Edit(//server/share/folder/**)", workingDir),
+  ).toBe(true);
+});
+
+test("File pattern: extended Windows drive path matches canonical drive pattern", () => {
+  const query = String.raw`Edit(\\?\C:\Users\Aaron\folder\file.md)`;
+  const workingDir = String.raw`C:\Users\Aaron\repo`;
+
+  expect(
+    matchesFilePattern(query, "Edit(C:/Users/Aaron/folder/**)", workingDir),
+  ).toBe(true);
+});
+
+test("File pattern: extended UNC pattern matches UNC query path", () => {
+  const query = String.raw`Edit(\\server\share\folder\file.md)`;
+  const workingDir = String.raw`C:\Users\Aaron\repo`;
+
+  expect(
+    matchesFilePattern(
+      query,
+      "Edit(//?/UNC/server/share/folder/**)",
+      workingDir,
+    ),
+  ).toBe(true);
+});