From 478164d5243a320219672ff4c54f5aefb633f901 Mon Sep 17 00:00:00 2001
From: Claudia Pellegrino <claui@users.noreply.github.com>
Date: Sun, 5 Feb 2023 20:48:17 +0100
Subject: [PATCH] Make `EventStream` implement `Event`

---
 extension/src/events.ts        | 12 ++++--------
 extension/src/events/stream.ts | 24 +++++++++---------------
 2 files changed, 13 insertions(+), 23 deletions(-)

diff --git a/extension/src/events.ts b/extension/src/events.ts
index aa68a3c..fd0c7dc 100644
--- a/extension/src/events.ts
+++ b/extension/src/events.ts
@@ -30,8 +30,7 @@ const onDidInitiallyFindTextDocument: Event<TextDocument> = (
 export const onDidInitiallyFindRelevantTextDocument: Event<TextDocument> =
   streamEvents(onDidInitiallyFindTextDocument)
     .through(excludeIrrelevantTextDocumentsByScheme)
-    .through(excludeIrrelevantTextDocumentsByLanguage)
-    .commit();
+    .through(excludeIrrelevantTextDocumentsByLanguage);
 
 export const onDidChangeRelevantTextDocument: Event<TextDocument> =
   streamEvents(workspace.onDidChangeTextDocument)
@@ -42,17 +41,14 @@ export const onDidChangeRelevantTextDocument: Event<TextDocument> =
       CHANGE_EVENT_THROTTLE_MILLIS,
       (e: TextDocumentChangeEvent) => e.document,
     )
-    .through(ignoreIfAlreadyClosed)
-    .commit();
+    .through(ignoreIfAlreadyClosed);
 
 export const onDidOpenRelevantTextDocument: Event<TextDocument> =
   streamEvents(workspace.onDidOpenTextDocument)
     .through(excludeIrrelevantTextDocumentsByScheme)
-    .through(excludeIrrelevantTextDocumentsByLanguage)
-    .commit();
+    .through(excludeIrrelevantTextDocumentsByLanguage);
 
 export const onDidCloseRelevantTextDocument: Event<TextDocument> =
   streamEvents(workspace.onDidCloseTextDocument)
     .through(excludeIrrelevantTextDocumentsByScheme)
-    .through(excludeIrrelevantTextDocumentsByLanguage)
-    .commit();
+    .through(excludeIrrelevantTextDocumentsByLanguage);
diff --git a/extension/src/events/stream.ts b/extension/src/events/stream.ts
index 8ee383c..ea587ef 100644
--- a/extension/src/events/stream.ts
+++ b/extension/src/events/stream.ts
@@ -6,25 +6,19 @@ interface EventStreamFunction<T, U, A extends Arr> {
   (...args: [...A, Event<T>]): Event<U>;
 }
 
-class EventStream<T> {
-  #upstreamEvent: Event<T>;
-
-  constructor(event: Event<T>) {
-    this.#upstreamEvent = event;
-  }
-
+interface EventStream<T> extends Event<T> {
   through<U, A extends Arr>(
     fn: EventStreamFunction<T, U, A>,
     ...args: A
-  ): EventStream<U> {
-    return streamEvents(fn(...args, this.#upstreamEvent));
-  }
-
-  commit(): Event<T> {
-    return this.#upstreamEvent;
-  }
+  ): EventStream<U>;
 }
 
 export function streamEvents<T>(event: Event<T>): EventStream<T> {
-  return new EventStream(event);
+  const stream: EventStream<T> = function (...args) {
+    return event(...args);
+  };
+  stream.through = (fn, ...args) => {
+    return streamEvents(fn(...args, event));
+  };
+  return stream;
 }