chore: extract Emitter and Signal to their own crate

2025-04-21 16:43:17 -04:00
parent f422888d37
commit a97cf73061
6 changed files with 403 additions and 0 deletions
--- a/emitter-and-signal/src/emitter_ext.rs
+++ b/emitter-and-signal/src/emitter_ext.rs
@@ -0,0 +1,147 @@
+use ext_trait::extension;
+use tokio::{select, task::JoinHandle};
+
+use super::emitter::{Capacity, Emitter, NextError};
+
+#[extension(pub trait EmitterExt)]
+impl<T> Emitter<T> {
+    fn map<M, F>(self, mut func: F, capacity: Capacity) -> (Emitter<M>, JoinHandle<()>)
+    where
+        T: Send + 'static + Clone,
+        M: Send + 'static + Clone,
+        F: Send + 'static + FnMut(T) -> M,
+    {
+        Emitter::new(
+            |mut publisher_stream| async move {
+                while let Some(publisher) = publisher_stream.wait().await {
+                    let Ok(mut subscription) = self.listen() else {
+                        return;
+                    };
+
+                    loop {
+                        select! {
+                            biased;
+                            _ = publisher.all_unsubscribed() => {
+                                break;
+                            }
+                            event_res = subscription.next() => {
+                                match event_res {
+                                    Ok(event) => publisher.publish(func(event)),
+                                    Err(NextError::Lagged { .. }) => {},
+                                    Err(NextError::ProducerExited(_)) => return,
+                                }
+                            }
+                        }
+                    }
+                }
+            },
+            capacity,
+        )
+    }
+
+    fn filter<F>(self, mut func: F, capacity: Capacity) -> (Emitter<T>, JoinHandle<()>)
+    where
+        T: Send + 'static + Clone,
+        F: Send + 'static + FnMut(&T) -> bool,
+    {
+        Emitter::new(
+            |mut publisher_stream| async move {
+                while let Some(publisher) = publisher_stream.wait().await {
+                    let Ok(mut subscription) = self.listen() else {
+                        return;
+                    };
+
+                    loop {
+                        select! {
+                            biased;
+                            _ = publisher.all_unsubscribed() => {
+                                break;
+                            }
+                            event_res = subscription.next() => {
+                                match event_res {
+                                    Ok(event) => if func(&event) {
+                                        publisher.publish(event)
+                                    },
+                                    Err(NextError::Lagged { .. }) => {},
+                                    Err(NextError::ProducerExited(_)) => return,
+                                }
+                            }
+                        }
+                    }
+                }
+            },
+            capacity,
+        )
+    }
+
+    fn filter_mut<F>(self, mut func: F, capacity: Capacity) -> (Emitter<T>, JoinHandle<()>)
+    where
+        T: Send + 'static + Clone,
+        F: Send + 'static + FnMut(&mut T) -> bool,
+    {
+        Emitter::new(
+            |mut publisher_stream| async move {
+                while let Some(publisher) = publisher_stream.wait().await {
+                    let Ok(mut subscription) = self.listen() else {
+                        return;
+                    };
+
+                    loop {
+                        select! {
+                            biased;
+                            _ = publisher.all_unsubscribed() => {
+                                break;
+                            }
+                            event_res = subscription.next() => {
+                                match event_res {
+                                    Ok(mut event) => if func(&mut event) {
+                                        publisher.publish(event)
+                                    },
+                                    Err(NextError::Lagged { .. }) => {},
+                                    Err(NextError::ProducerExited(_)) => return,
+                                }
+                            }
+                        }
+                    }
+                }
+            },
+            capacity,
+        )
+    }
+
+    fn filter_map<M, F>(self, mut func: F, capacity: Capacity) -> (Emitter<M>, JoinHandle<()>)
+    where
+        T: Send + 'static + Clone,
+        M: Send + 'static + Clone,
+        F: Send + 'static + FnMut(T) -> Option<M>,
+    {
+        Emitter::new(
+            |mut publisher_stream| async move {
+                while let Some(publisher) = publisher_stream.wait().await {
+                    let Ok(mut subscription) = self.listen() else {
+                        return;
+                    };
+
+                    loop {
+                        select! {
+                            biased;
+                            _ = publisher.all_unsubscribed() => {
+                                break;
+                            }
+                            event_res = subscription.next() => {
+                                match event_res {
+                                    Ok(event) => if let Some(mapped) = func(event) {
+                                        publisher.publish(mapped)
+                                    },
+                                    Err(NextError::Lagged { .. }) => {},
+                                    Err(NextError::ProducerExited(_)) => return,
+                                }
+                            }
+                        }
+                    }
+                }
+            },
+            capacity,
+        )
+    }
+}