From 43bc3cb02952d9ba2784587633b2a2daff01c2df Mon Sep 17 00:00:00 2001
From: Filipe Rodrigues <filipejacintorodrigues1@gmail.com>
Date: Wed, 21 Feb 2024 12:37:09 +0000
Subject: [PATCH] Added some tests to `dynatos_reactive::{effect, trigger}`.

---
 dynatos-reactive/src/effect.rs  | 76 +++++++++++++++++++++++++++++++++
 dynatos-reactive/src/trigger.rs | 40 +++++++++++++++++
 2 files changed, 116 insertions(+)

diff --git a/dynatos-reactive/src/effect.rs b/dynatos-reactive/src/effect.rs
index 0da0c2e..f48d5b1 100644
--- a/dynatos-reactive/src/effect.rs
+++ b/dynatos-reactive/src/effect.rs
@@ -195,3 +195,79 @@ impl fmt::Debug for WeakEffect {
 		f.debug_struct("WeakEffect").finish_non_exhaustive()
 	}
 }
+
+#[cfg(test)]
+mod test {
+	// Imports
+	use {super::*, std::cell::OnceCell};
+
+	/// Leaks a value and returns a `&'static T`
+	///
+	/// This is useful because `&'static T` is `Copy`,
+	/// so we don't need to worry about cloning `Rc`s to
+	/// pass variables to effects.
+	fn leaked<T>(value: T) -> &'static T {
+		Box::leak(Box::new(value))
+	}
+
+	/// Ensures the function returned by `Effect::running` is the same as the future being run.
+	#[test]
+	fn running() {
+		// Create an effect, and save the running effect within it to `running`.
+		let running = self::leaked(OnceCell::new());
+		let effect = Effect::new(move || {
+			running
+				.set(Effect::running().expect("Future wasn't running"))
+				.expect("Unable to set running effect");
+		});
+
+		// Then ensure the running effect is the same as the one created.
+		let running = running
+			.get()
+			.expect("Running effect missing")
+			.upgrade()
+			.expect("Running effect was dropped");
+		assert_eq!(effect, running);
+	}
+
+	/// Ensures the function returned by `Effect::running` is the same as the future being run,
+	/// while running stacked futures
+	#[test]
+	fn running_stacked() {
+		// Create 2 stacked effects, saving the running within each to `running1` and `running2`.
+		// `running1` contains the top-level effect, while `running2` contains the inner one.
+		let running_top = self::leaked(OnceCell::new());
+		let running_bottom = self::leaked(OnceCell::new());
+		let effect = Effect::new(move || {
+			running_top
+				.set(Effect::running().expect("Future wasn't running"))
+				.expect("Unable to set running effect");
+
+			let effect = Effect::new(move || {
+				running_bottom
+					.set(Effect::running().expect("Future wasn't running"))
+					.expect("Unable to set running effect");
+			});
+
+			// Then ensure the bottom-level running effect is the same as the one created.
+			let running_bottom = running_bottom
+				.get()
+				.expect("Running effect missing")
+				.upgrade()
+				.expect("Running effect was dropped");
+			assert_eq!(effect, running_bottom);
+		});
+
+		// Then ensure the top-level running effect is the same as the one created.
+		let running_top = running_top
+			.get()
+			.expect("Running effect missing")
+			.upgrade()
+			.expect("Running effect was dropped");
+		assert_eq!(effect, running_top);
+
+		// And that the bottom-level running effect was already dropped
+		let running_bottom = running_bottom.get().expect("Running effect missing").upgrade();
+		assert_eq!(running_bottom, None);
+	}
+}
diff --git a/dynatos-reactive/src/trigger.rs b/dynatos-reactive/src/trigger.rs
index d029b7c..12b2bae 100644
--- a/dynatos-reactive/src/trigger.rs
+++ b/dynatos-reactive/src/trigger.rs
@@ -106,3 +106,43 @@ impl IntoSubscriber for T {
 		body
 	}
 }
+
+#[cfg(test)]
+mod test {
+	// Imports
+	use {
+		super::*,
+		std::{cell::Cell, mem},
+	};
+
+	#[test]
+	fn basic() {
+		thread_local! {
+			/// Counts the number of times the effect was run
+			static TRIGGERS: Cell<usize> = const { Cell::new(0) };
+		}
+
+		// Create the effect and reset the flag
+		let effect = Effect::new(move || TRIGGERS.set(TRIGGERS.get() + 1));
+
+		// Then create the trigger, and ensure it wasn't triggered
+		// by just creating it and adding the subscriber
+		let trigger = Trigger::new();
+		trigger.add_subscriber(effect.downgrade());
+		assert_eq!(TRIGGERS.get(), 1, "Trigger was triggered early");
+
+		// Then trigger and ensure it was triggered
+		trigger.trigger();
+		assert_eq!(TRIGGERS.get(), 2, "Trigger was not triggered");
+
+		// Then add the subscriber again and ensure the effect isn't run twice
+		trigger.add_subscriber(effect.downgrade());
+		trigger.trigger();
+		assert_eq!(TRIGGERS.get(), 3, "Trigger ran effect multiple times");
+
+		// Finally drop the effect and try again
+		mem::drop(effect);
+		trigger.trigger();
+		assert_eq!(TRIGGERS.get(), 3, "Trigger was triggered after effect was dropped");
+	}
+}