APP-2977: Handle AppView polling errors (#11590)

src/lib/async/until.test.ts

@@ -0,0 +1,42 @@
+import {describe, expect, it, jest} from '@jest/globals'
+
+import {until} from './until'
+
+describe('until', () => {
+  it('passes attempt errors to the condition', async () => {
+    const error = new Error('failed')
+    const fn = jest
+      .fn<() => Promise<string>>()
+      .mockRejectedValueOnce(error)
+      .mockResolvedValue('ready')
+    const cond = jest.fn((value: string | undefined) => value === 'ready')
+
+    await expect(until(2, 0, cond, fn)).resolves.toBe(true)
+    expect(fn).toHaveBeenCalledTimes(2)
+    expect(cond).toHaveBeenNthCalledWith(1, undefined, error)
+    expect(cond).toHaveBeenNthCalledWith(2, 'ready', undefined)
+  })
+
+  it('returns false when every attempt rejects', async () => {
+    const fn = jest
+      .fn<() => Promise<string>>()
+      .mockRejectedValue(new Error('failed'))
+    const cond = jest.fn((_value: string | undefined) => false)
+
+    await expect(until(2, 0, cond, fn)).resolves.toBe(false)
+    expect(fn).toHaveBeenCalledTimes(2)
+    expect(cond).toHaveBeenCalledTimes(2)
+  })
+
+  it('can stop when an attempt rejects', async () => {
+    const error = new Error('failed')
+    const fn = jest.fn<() => Promise<string>>().mockRejectedValue(error)
+    const cond = jest.fn(
+      (_value: string | undefined, err: unknown) => err === error,
+    )
+
+    await expect(until(2, 0, cond, fn)).resolves.toBe(true)
+    expect(fn).toHaveBeenCalledTimes(1)
+    expect(cond).toHaveBeenCalledWith(undefined, error)
+  })
+})

src/lib/async/until.ts

@@ -1,9 +1,12 @@
 import {timeout} from './timeout'
 
+/**
+ * Retries an async operation until its result or error matches `cond`.
+ */
 export async function until<T>(
   retries: number,
   delay: number,
-  cond: (v: T, err: any) => boolean,
+  cond: (v: T | undefined, err: unknown) => boolean,
   fn: () => Promise<T>,
 ): Promise<boolean> {
   while (retries > 0) {
@@ -12,10 +15,8 @@ export async function until<T>(
       if (cond(v, undefined)) {
         return true
       }
-    } catch (e: any) {
-      // TODO: change the type signature of cond to accept undefined
-      // however this breaks every existing usage of until -sfn
-      if (cond(undefined as unknown as T, e)) {
+    } catch (err) {
+      if (cond(undefined, err)) {
         return true
       }
     }

src/lib/generate-starterpack.ts

@@ -141,7 +141,10 @@ function createListItem({
 async function whenAppViewReady(
   client: Client,
   uri: string,
-  fn: (res?: app.bsky.graph.getStarterPack.$OutputBody) => boolean,
+  fn: (
+    res: app.bsky.graph.getStarterPack.$OutputBody | undefined,
+    err: unknown,
+  ) => boolean,
 ) {
   await until(
     5, // 5 tries