Translate the older FileNode rights, so Rename and Delete work again

Deleting a file did nothing on the live 0.15.5 server, with no error: the menu
items are gated on myRights.mayDelete and myRights.mayRename, and 0.16 was the
release that split rights up. Before it a node carried mayRead, mayWrite and
mayShare, with the one mayWrite covering everything the newer release names
separately — so both items sat permanently disabled.

Widen mayWrite into the four rights the newer shape names, alongside the
nodeType normalisation, and the UI can keep reading the 0.16 vocabulary.

web/src/lib/__tests__/filenode.test.ts

@@ -1,6 +1,6 @@
 import { afterEach, describe, expect, it } from "vitest";
 import { client } from "@/jmap/client";
-import { directoryCreate, fileCreate, fileNodeProps, supportsNodeType, withNodeType } from "../filenode";
+import { directoryCreate, fileCreate, fileNodeProps, supportsNodeType, normalizeFileNodes } from "../filenode";
 import type { FileNode, JmapSession } from "@/jmap/types";
 
 /**
@@ -33,7 +33,7 @@ describe("on Stalwart 0.16 and newer", () => {
   it("leaves what the server reported alone", () => {
     client.session = session(NEW_SERVER);
     const nodes = [{ id: "1", name: "x", nodeType: "directory" }] as Partial<FileNode>[];
-    expect(withNodeType(nodes)).toEqual(nodes);
+    expect(normalizeFileNodes(nodes)).toEqual(nodes);
   });
 });
 
@@ -62,7 +62,7 @@ describe("on Stalwart before 0.16", () => {
 
   it("works out nodeType from the file properties, so folders stay folders", () => {
     client.session = session(OLD_SERVER);
-    const out = withNodeType([
+    const out = normalizeFileNodes([
       { id: "1", name: "Documents", blobId: null, size: null, type: null },
       { id: "2", name: "notes.txt", blobId: "b1", size: 11, type: "text/plain" },
       { id: "3", name: "empty.txt", blobId: "b2", size: 0, type: null },
@@ -72,7 +72,7 @@ describe("on Stalwart before 0.16", () => {
 
   it("does not overwrite a nodeType that did come back", () => {
     client.session = session(OLD_SERVER);
-    const out = withNodeType([{ id: "1", name: "x", nodeType: "symlink", blobId: "b1" }] as Partial<FileNode>[]);
+    const out = normalizeFileNodes([{ id: "1", name: "x", nodeType: "symlink", blobId: "b1" }] as Partial<FileNode>[]);
     expect(out[0]!.nodeType).toBe("symlink");
   });
 });
@@ -81,3 +81,39 @@ it("assumes the older shape when there is no session yet", () => {
   client.session = null;
   expect(supportsNodeType()).toBe(false);
 });
+
+/**
+ * Rights were split up in 0.16. Before that a node carried mayRead / mayWrite /
+ * mayShare, with mayWrite covering everything the newer release names
+ * separately — so Rename and Delete sat permanently greyed out, doing nothing
+ * and saying nothing.
+ */
+describe("rights on a pre-0.16 server", () => {
+  const oldRights = (mayWrite: boolean) => ({ mayRead: true, mayWrite, mayShare: false });
+
+  it("widens mayWrite into the rights the UI gates on", () => {
+    client.session = session(OLD_SERVER);
+    const [node] = normalizeFileNodes([{ id: "1", name: "x", myRights: oldRights(true) }] as unknown as Partial<FileNode>[]);
+    expect(node!.myRights).toMatchObject({ mayRead: true, mayAddChildren: true, mayRename: true, mayDelete: true, mayModifyContent: true, mayShare: false });
+  });
+
+  it("does not hand out rights the server withheld", () => {
+    client.session = session(OLD_SERVER);
+    const [node] = normalizeFileNodes([{ id: "1", name: "x", myRights: oldRights(false) }] as unknown as Partial<FileNode>[]);
+    expect(node!.myRights).toMatchObject({ mayRename: false, mayDelete: false, mayModifyContent: false });
+  });
+
+  it("leaves rights that already use the newer names untouched", () => {
+    client.session = session(OLD_SERVER);
+    const newer = { mayRead: true, mayAddChildren: true, mayRename: true, mayDelete: false, mayModifyContent: true, mayShare: true };
+    const [node] = normalizeFileNodes([{ id: "1", name: "x", myRights: newer }] as unknown as Partial<FileNode>[]);
+    expect(node!.myRights).toEqual(newer);
+  });
+
+  it("copes with a node that reported no rights at all", () => {
+    client.session = session(OLD_SERVER);
+    const [node] = normalizeFileNodes([{ id: "1", name: "x" }] as Partial<FileNode>[]);
+    expect(node!.myRights).toBeUndefined();
+    expect(node!.nodeType).toBe("directory");
+  });
+});