fix(app): better review/filetree empty states (#16221)

Co-authored-by: Adam <2363879+adamdotdevin@users.noreply.github.com>

packages/app/src/pages/session/session-side-panel.tsx

@@ -87,6 +87,21 @@ export function SessionSidePanel(props: {
     return out
   })
 
+  const empty = (msg: string) => (
+    <div class="h-full flex flex-col">
+      <div class="h-12 shrink-0" aria-hidden />
+      <div class="flex-1 pb-30 flex items-center justify-center text-center">
+        <div class="text-12-regular text-text-weak">{msg}</div>
+      </div>
+    </div>
+  )
+
+  const nofiles = createMemo(() => {
+    const state = file.tree.state("")
+    if (!state?.loaded) return false
+    return file.tree.children("").length === 0
+  })
+
   const normalizeTab = (tab: string) => {
     if (!tab.startsWith("file://")) return tab
     return file.tab(tab)
@@ -145,17 +160,8 @@ export function SessionSidePanel(props: {
 
   const [store, setStore] = createStore({
     activeDraggable: undefined as string | undefined,
-    fileTreeScrolled: false,
   })
 
-  let changesEl: HTMLDivElement | undefined
-  let allEl: HTMLDivElement | undefined
-
-  const syncFileTreeScrolled = (el?: HTMLDivElement) => {
-    const next = (el?.scrollTop ?? 0) > 0
-    setStore("fileTreeScrolled", (current) => (current === next ? current : next))
-  }
-
   const handleDragStart = (event: unknown) => {
     const id = getDraggableId(event)
     if (!id) return
@@ -176,11 +182,6 @@ export function SessionSidePanel(props: {
     setStore("activeDraggable", undefined)
   }
 
-  createEffect(() => {
-    if (!layout.fileTree.opened()) return
-    syncFileTreeScrolled(fileTreeTab() === "changes" ? changesEl : allEl)
-  })
-
   createEffect(() => {
     if (!file.ready()) return
 
@@ -354,7 +355,7 @@ export function SessionSidePanel(props: {
                 class="h-full"
                 data-scope="filetree"
               >
-                <Tabs.List data-scrolled={store.fileTreeScrolled ? "" : undefined}>
+                <Tabs.List>
                   <Tabs.Trigger value="changes" class="flex-1" classes={{ button: "w-full" }}>
                     {reviewCount()}{" "}
                     {language.t(reviewCount() === 1 ? "session.review.change.one" : "session.review.change.other")}
@@ -363,12 +364,7 @@ export function SessionSidePanel(props: {
                     {language.t("session.files.all")}
                   </Tabs.Trigger>
                 </Tabs.List>
-                <Tabs.Content
-                  value="changes"
-                  ref={(el: HTMLDivElement) => (changesEl = el)}
-                  onScroll={(e: UIEvent & { currentTarget: HTMLDivElement }) => syncFileTreeScrolled(e.currentTarget)}
-                  class="bg-background-stronger px-3 py-0"
-                >
+                <Tabs.Content value="changes" class="bg-background-stronger px-3 py-0">
                   <Switch>
                     <Match when={hasReview()}>
                       <Show
@@ -382,6 +378,7 @@ export function SessionSidePanel(props: {
                       >
                         <FileTree
                           path=""
+                          class="pt-3"
                           allowed={diffFiles()}
                           kinds={kinds()}
                           draggable={false}
@@ -390,25 +387,22 @@ export function SessionSidePanel(props: {
                         />
                       </Show>
                     </Match>
-                    <Match when={true}>
-                      <div class="mt-8 text-center text-12-regular text-text-weak">
-                        {language.t("session.review.noChanges")}
-                      </div>
-                    </Match>
+                    <Match when={true}>{empty(language.t("session.review.noChanges"))}</Match>
                   </Switch>
                 </Tabs.Content>
-                <Tabs.Content
-                  value="all"
-                  ref={(el: HTMLDivElement) => (allEl = el)}
-                  onScroll={(e: UIEvent & { currentTarget: HTMLDivElement }) => syncFileTreeScrolled(e.currentTarget)}
-                  class="bg-background-stronger px-3 py-0"
-                >
-                  <FileTree
-                    path=""
-                    modified={diffFiles()}
-                    kinds={kinds()}
-                    onFileClick={(node) => openTab(file.tab(node.path))}
-                  />
+                <Tabs.Content value="all" class="bg-background-stronger px-3 py-0">
+                  <Switch>
+                    <Match when={nofiles()}>{empty(language.t("session.files.empty"))}</Match>
+                    <Match when={true}>
+                      <FileTree
+                        path=""
+                        class="pt-3"
+                        modified={diffFiles()}
+                        kinds={kinds()}
+                        onFileClick={(node) => openTab(file.tab(node.path))}
+                      />
+                    </Match>
+                  </Switch>
                 </Tabs.Content>
               </Tabs>
             </div>