Land on a page of the space after deleting the room you are in

e2e/USER_STORIES.md

@@ -305,6 +305,18 @@ Acceptance:
   and removes it from the sidebar.
 - bob sees neither "Edit Room" nor "Delete Room" in the room's detail menu.
 
+### US-121 — Land somewhere after deleting the room you are in
+
+As admin, I want deleting the room I am reading to put me on a page of the
+space, so that I am not stranded on a screen with nothing on it.
+
+Acceptance:
+
+- Confirming the deletion leaves admin on a page below the space root, with the
+  space's remaining rooms listed beside it.
+- Entering the space again from the rail lands on a page, rather than returning
+  to the room that was deleted or to the empty root.
+
 ### US-021 — Request access to a private room and get approved
 
 As carol, I want to ask to join a closed room and be let in, so that I can read

e2e/specs/rooms.spec.ts

@@ -300,6 +300,36 @@ test("US-020 create, edit, and delete a room", async ({seed, as}) => {
   await expect(bob.getByRole("button", {name: "Delete Room"})).toHaveCount(0)
 })
 
+test("US-121 land somewhere after deleting the room you are in", async ({seed, as}) => {
+  const scenario = await seed(({relay, user}) => {
+    const space = relay("space")
+
+    space.room("general", {name: "General"})
+    space.room("wardroom", {name: "Wardroom"})
+    space.join(user.admin, "general")
+    space.join(user.admin, "wardroom")
+  })
+
+  const {url} = scenario.space("space")
+  const admin = await as(users.admin, roomPath(url, "wardroom"))
+
+  await openRoomDetail(admin)
+  await openRoomDetailMenu(admin)
+  await admin.getByRole("button", {name: "Delete Room"}).click()
+  await admin.getByRole("button", {name: "Confirm"}).click()
+
+  // The space root renders nothing on a wide screen; it hands off to whichever page of the space
+  // was open last, and the room that was just deleted is the page it remembers.
+  await expect(admin).toHaveURL(pathPattern(spacePath(url) + "/"))
+  await expect(roomLink(admin, "General")).toBeVisible()
+
+  // Entering the space from the rail reads the same memory, so it has to land somewhere too.
+  await admin.locator('.primary-nav [data-tip^="space"]').click()
+
+  await expect(admin).toHaveURL(pathPattern(spacePath(url) + "/"))
+  await expect(roomLink(admin, "General")).toBeVisible()
+})
+
 test("US-021 request access to a private room and get approved", async ({seed, as}) => {
   const scenario = await seed(({relay, user, at}) => {
     const space = relay("space")

src/app/components/RoomDetailMenu.svelte

@@ -14,7 +14,7 @@
   import {app, roomLists, rooms} from "@app/core"
   import {joinRoom, leaveRoom} from "@app/access"
   import {deriveUserIsRoomAdmin, deriveUserRoomMembershipStatus} from "@app/rooms"
-  import {makeSpacePath} from "@app/routes"
+  import {forgetSpacePage, makeSpacePath} from "@app/routes"
   import {navigate, pushModal} from "@app/modal"
   import {pushToast} from "@app/toast"
 
@@ -62,6 +62,8 @@
           pushToast({theme: "error", message})
         } else {
           await $roomLists.removeRoom(h, url).then(publish)
+
+          forgetSpacePage(url)
           navigate(makeSpacePath(url))
         }
       },

src/app/routes.ts

@@ -40,8 +40,13 @@ export const lastSpaceUrl = writable<string | undefined>(undefined)
 export const setupHistory = () =>
   page.subscribe($page => {
     if ($page.params.relay) {
-      lastPageBySpaceUrl.set($page.params.relay, $page.url.pathname)
+      const url = decodeRelay($page.params.relay)
-      lastSpaceUrl.set(decodeRelay($page.params.relay))
+
+      if ($page.url.pathname !== makeSpacePath(url)) {
+        lastPageBySpaceUrl.set(url, $page.url.pathname)
+      }
+
+      lastSpaceUrl.set(url)
     }
 
     if ($page.params.chat) {
@@ -88,8 +93,10 @@ export const makeSpacePath = (url: string, ...extra: (string | undefined)[]) =>
   return path
 }
 
+export const forgetSpacePage = (url: string) => lastPageBySpaceUrl.delete(url)
+
 export const makeSpaceEntryPath = (url: string) => {
-  const prevPath = lastPageBySpaceUrl.get(encodeRelay(url))
+  const prevPath = lastPageBySpaceUrl.get(url)
 
   if (prevPath) {
     return prevPath