Checking if Gameplay Ability is Active.

Here some useful functions for your custom Ability System Component to determine if an ability is Active or not.

bool UKaosAbilitySystemComponent::IsAbilityActive(const FGameplayTagContainer* WithTags, const FGameplayTagContainer* WithoutTags, UGameplayAbility* Ignore)
{
	ABILITYLIST_SCOPE_LOCK();

	for (FGameplayAbilitySpec& Spec : ActivatableAbilities.Items)
	{
		if (!Spec.IsActive() || Spec.Ability == nullptr || Spec.Ability == Ignore)
		{
			continue;
		}

		const bool WithTagPass = (!WithTags || Spec.Ability->AbilityTags.HasAny(*WithTags));
		const bool WithoutTagPass = (!WithoutTags || !Spec.Ability->AbilityTags.HasAny(*WithoutTags));

		if (WithTagPass && WithoutTagPass)
		{
			return true;
		}
	}
	return false;
}

bool UKaosAbilitySystemComponent::IsAbilityActive(const FGameplayAbilitySpecHandle& InHandle)
{
	ABILITYLIST_SCOPE_LOCK();
	FGameplayAbilitySpec* Spec = FindAbilitySpecFromHandle(InHandle);
	return Spec ? Spec->IsActive() : false;
}

bool UKaosAbilitySystemComponent::IsAbilityActive(TSubclassOf<UKaosGameplayAbility> AbilityClass, UObject* SourceObject)
{
	ABILITYLIST_SCOPE_LOCK();

	FGameplayAbilitySpec* Spec;

	if (SourceObject)
	{
		Spec = FindAbilitySpecByClassAndSource(AbilityClass, SourceObject);
	}
	else
	{
		Spec = FindAbilitySpecFromClass(AbilityClass);
	}

	if (Spec)
	{
		return Spec->IsActive();
	}
	return false;
}

This is a very short post, and the functions should make some sense just by reading them.