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CppUtils
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import CppUtils.UnitTest.EventWatcher;orimport CppUtils;

CppUtils::UnitTest::EventWatcher<String::Hasher eventName, class... Args>

CLASS

Thread-safe RAII observer for monitoring emitted events and collecting payloads.

Description

Section titled “Description”

Subscribes to the designated event upon construction and unsubscribes automatically upon destruction. Provides blocking synchronization utilities (waitForEvent, waitForOccurrences) and thread-safe inspection of occurrence counts and captured payloads.

Template parameterDescription
eventNameCompile-time hashed string identifying the event.
ArgsTypes of the event payload arguments.

Public types

Section titled “Public types”

Payload

Section titled “Payload”
using CppUtils::UnitTest::EventWatcher<eventName, Args>::Payload = std::conditional_t<sizeof...(Args) == 0, std::monostate, std::conditional_t<sizeof...(Args) == 1, std::tuple_element_t<0, std::tuple<Args..., void>>, std::tuple<Args...>>>;

Public methods

Section titled “Public methods”
explicit EventWatcher::EventWatcher(auto& emitter);

Subscribes the watcher to the specified event emitter.

ParameterDescription
emitterReference to the event emitter to monitor.
EventWatcher::~EventWatcher();
EventWatcher::EventWatcher(const EventWatcher&) = delete;
EventWatcher& EventWatcher::operator=(const EventWatcher&) = delete;
EventWatcher::EventWatcher(EventWatcher&& other) noexcept;
EventWatcher& EventWatcher::operator=(EventWatcher&& other) noexcept;
[[nodiscard]] auto EventWatcher::count() const noexcept -> std::size_t;

Returns the total number of times the monitored event has been fired.

Returns: Event occurrence count.

[[nodiscard]] auto EventWatcher::hasOccurred() const noexcept -> bool;

Checks if the monitored event has occurred at least once.

Returns: True if count() > 0.

template <Chrono::Duration TimeoutDuration = std::chrono::milliseconds>
auto EventWatcher::waitForOccurrences(std::size_t targetCount, TimeoutDuration timeout = std::chrono::milliseconds{1000}) -> bool;

Blocks until the event has been fired at least targetCount times or timeout expires.

Template parameterDescription
TimeoutDurationDuration type (defaults to std::chrono::milliseconds).
ParameterDescription
targetCountNumber of occurrences to wait for.
timeoutMaximum duration to wait before giving up.

Returns: True if the target occurrence count was reached before the timeout expired.

template <Chrono::Duration TimeoutDuration = std::chrono::milliseconds>
auto EventWatcher::waitForEvent(TimeoutDuration timeout = std::chrono::milliseconds{1000}) -> bool;

Blocks until the event occurs at least once or timeout expires.

Template parameterDescription
TimeoutDurationDuration type (defaults to std::chrono::milliseconds).
ParameterDescription
timeoutMaximum duration to wait before giving up.

Returns: True if the event occurred before the timeout expired.

[[nodiscard]] auto EventWatcher::occurrences() const -> auto;

Acquires exclusive locked access to the recorded state and payloads.

Returns: Unique accessor locking the internal state.

auto EventWatcher::clear() -> void;

Resets the event occurrence count to zero and clears recorded payloads.