Fix Suggestion Pattern when text is empty (#1943)

* fix + debounce improvement

* comment

* improved existing function to be more generic

ElementX/Sources/Other/Extensions/Publisher.swift

@@ -25,16 +25,23 @@ extension Publisher where Self.Failure == Never {
  }
 }
 
-extension Publisher where Output == String, Failure == Never {
- /// Debounce text queries and remove duplicates.
- /// Clearing the text publishes the update immediately.
- func debounceAndRemoveDuplicates() -> AnyPublisher<String, Never> {
+extension Publisher where Output: Equatable, Failure == Never {
+ func debounceAndRemoveDuplicates<S: Scheduler>(on scheduler: S, delay: @escaping (Output) -> S.SchedulerTimeType.Stride) -> AnyPublisher<Output, Never> {
  map { query in
- let milliseconds = query.isEmpty ? 0 : 250
- return Just(query).delay(for: .milliseconds(milliseconds), scheduler: DispatchQueue.main)
+ Just(query).delay(for: delay(query), scheduler: scheduler)
  }
  .switchToLatest()
  .removeDuplicates()
  .eraseToAnyPublisher()
  }
 }
+
+extension Publisher where Output == String, Failure == Never {
+ /// Debounce text queries and remove duplicates.
+ /// Clearing the text publishes the update immediately.
+ func debounceTextQueriesAndRemoveDuplicates() -> AnyPublisher<String, Never> {
+ debounceAndRemoveDuplicates(on: DispatchQueue.main) { query in
+ query.isEmpty ? .milliseconds(0) : .milliseconds(250)
+ }
+ }
+}

ElementX/Sources/Screens/ComposerToolbar/CompletionSuggestionService.swift

@@ -55,8 +55,10 @@ final class CompletionSuggestionService: CompletionSuggestionServiceProtocol {
  return membersSuggestion
  }
  }
- .debounce(for: 0.5, scheduler: DispatchQueue.main)
- .eraseToAnyPublisher()
+ // We only debounce if the suggestion is nil
+ .debounceAndRemoveDuplicates(on: DispatchQueue.main) { [weak self] _ in
+ self?.suggestionTriggerSubject.value != nil ? .milliseconds(500) : .milliseconds(0)
+ }
 
  Task {
  switch await roomProxy.canUserTriggerRoomNotification(userID: roomProxy.ownUserID) {
@@ -73,6 +75,10 @@ final class CompletionSuggestionService: CompletionSuggestionServiceProtocol {
  }
 
  private static func isIncluded(searchText: String, userID: String, displayName: String?) -> Bool {
+ // If the search text is empty give back all the results
+ guard !searchText.isEmpty else {
+ return true
+ }
  let containedInUserID = userID.localizedStandardContains(searchText.lowercased())
 
  let containedInDisplayName: Bool

ElementX/Sources/Screens/InviteUsersScreen/InviteUsersScreenViewModel.swift

@@ -95,7 +95,7 @@ class InviteUsersScreenViewModel: InviteUsersScreenViewModelType, InviteUsersScr
  private func setupSubscriptions(selectedUsers: CurrentValuePublisher<[UserProfileProxy], Never>) {
  context.$viewState
  .map(\.bindings.searchQuery)
- .debounceAndRemoveDuplicates()
+ .debounceTextQueriesAndRemoveDuplicates()
  .sink { [weak self] _ in
  self?.fetchUsers()
  }

ElementX/Sources/Screens/StartChatScreen/StartChatScreenViewModel.swift

@@ -92,7 +92,7 @@ class StartChatScreenViewModel: StartChatScreenViewModelType, StartChatScreenVie
  private func setupBindings() {
  context.$viewState
  .map(\.bindings.searchQuery)
- .debounceAndRemoveDuplicates()
+ .debounceTextQueriesAndRemoveDuplicates()
  .sink { [weak self] _ in
  self?.fetchUsers()
  }

UnitTests/Sources/CompletionSuggestionServiceTests.swift

@@ -87,4 +87,26 @@ final class CompletionSuggestionServiceTests: XCTestCase {
  service.setSuggestionTrigger(.init(type: .user, text: "every"))
  try await deferred.fulfill()
  }
+
+ func testUserSuggestionsWithEmptyText() async throws {
+ let alice: RoomMemberProxyMock = .mockAlice
+ let bob: RoomMemberProxyMock = .mockBob
+ let members: [RoomMemberProxyMock] = [alice, bob, .mockMe]
+ let roomProxyMock = RoomProxyMock(with: .init(displayName: "test", members: members, canUserTriggerRoomNotification: true))
+ let service = CompletionSuggestionService(roomProxy: roomProxyMock, areSuggestionsEnabled: true)
+
+ var deferred = deferFulfillment(service.suggestionsPublisher) { suggestions in
+ suggestions == []
+ }
+
+ try await deferred.fulfill()
+
+ deferred = deferFulfillment(service.suggestionsPublisher) { suggestions in
+ suggestions == [.user(item: .init(id: alice.userID, displayName: alice.displayName, avatarURL: alice.avatarURL)),
+ .user(item: .init(id: bob.userID, displayName: bob.displayName, avatarURL: bob.avatarURL)),
+ .allUsers(item: .allUsersMention(roomAvatar: nil))]
+ }
+ service.setSuggestionTrigger(.init(type: .user, text: ""))
+ try await deferred.fulfill()
+ }
 }