| 1 | export type PendingNavigationRequest<T extends object> = T & { |
| 2 | seq: number; |
| 3 | resolve: () => void; |
| 4 | }; |
| 5 | |
| 6 | export type NavigationCoalescingRefs<T extends object> = { |
| 7 | seqRef: { current: number }; |
| 8 | runningRef: { current: boolean }; |
| 9 | pendingRef: { current: PendingNavigationRequest<T> | null }; |
| 10 | }; |
| 11 | |
| 12 | export function enqueueNavigationRequest<T extends object>( |
| 13 | refs: NavigationCoalescingRefs<T>, |
| 14 | input: T, |
| 15 | run: (request: PendingNavigationRequest<T>) => Promise<void>, |
| 16 | ): Promise<void> { |
| 17 | const seq = refs.seqRef.current + 1; |
| 18 | refs.seqRef.current = seq; |
| 19 | |
| 20 | let resolve!: () => void; |
| 21 | const promise = new Promise<void>((res) => { |
| 22 | resolve = res; |
| 23 | }); |
| 24 | const request: PendingNavigationRequest<T> = { ...input, seq, resolve }; |
| 25 | |
| 26 | const start = (next: PendingNavigationRequest<T>) => { |
| 27 | refs.runningRef.current = true; |
| 28 | void (async () => { |
| 29 | try { |
| 30 | await run(next); |
| 31 | } catch { |
| 32 | // run() is expected to handle user-visible failures. The scheduler keeps |
| 33 | // navigation promises non-rejecting so event handlers cannot leak |
| 34 | // unhandled rejections. |
| 35 | } finally { |
| 36 | next.resolve(); |
| 37 | const pending = refs.pendingRef.current; |
| 38 | if (pending) { |
| 39 | refs.pendingRef.current = null; |
| 40 | start(pending); |
| 41 | } else { |
| 42 | refs.runningRef.current = false; |
| 43 | } |
| 44 | } |
| 45 | })(); |
| 46 | }; |
| 47 | |
| 48 | if (refs.runningRef.current) { |
| 49 | refs.pendingRef.current?.resolve(); |
| 50 | refs.pendingRef.current = request; |
| 51 | return promise; |
| 52 | } |
| 53 | |
| 54 | start(request); |
| 55 | return promise; |
| 56 | } |
| 57 | |
| 58 | export type PendingOpenTopicRequest = PendingNavigationRequest<{ |
| 59 | scope: string; |
| 60 | workspaceRoot: string; |
| 61 | topicId: string; |
| 62 | sessionPath?: string; |
| 63 | }>; |
| 64 | |
| 65 | export type OpenTopicRequestInput = Omit<PendingOpenTopicRequest, "seq" | "resolve">; |
| 66 | |
| 67 | export type OpenTopicCoalescingRefs = NavigationCoalescingRefs<OpenTopicRequestInput>; |
| 68 | |
| 69 | export function enqueueOpenTopicRequest( |
| 70 | refs: OpenTopicCoalescingRefs, |
| 71 | input: OpenTopicRequestInput, |
| 72 | run: (request: PendingOpenTopicRequest) => Promise<void>, |
| 73 | ): Promise<void> { |
| 74 | return enqueueNavigationRequest(refs, input, run); |
| 75 | } |
| 76 |