Migrate to eventNameH-style API; update read functions (#49)

* Add dep on event-emitter

* Add coercion to event emitter

* Replace most onX fns with eventH

* Update exports to modern conventions

* Add missing handlers for Writable/Readable

* Update read functions / define dataH* handlers

* Update tests

* Drop unneeded test dep

* Reimplement readEither

This was dropped in a previous commit

* Add changelog entry

* Fix docs on readEither

Author: JordanMartinez

CHANGELOG.md

@@ -6,15 +6,35 @@ Notable changes to this project are documented in this file. The format is based
 
 Breaking changes:
 - Update `node-buffer` to `v9.0.0` (#48 by @JordanMartinez)
+- Reimplement event handlers using `eventNameH`-style API (#49 by @JordanMartinez)
+
+  Previously, one would write something like the following, and be unable to remove
+  the resulting listener.
+  ```purs
+  Stream.onData stream \buffer -> do
+    ...
+  ```
+
+  Now, one writes such a thing via `on` (or a similar function) from `node-event-emitter`:
+  ```purs
+  -- if the listener should be removed later, use `on`.
+  removeListener <- stream # on dataH \buffer -> do
+    ...
+  -- if it doesn't need to be removed, use `on_`.
+  stream # on_ dataH \buffer -> do
+    ...
+  ```
 
 New features:
+- Added event handlers for `Writeable` streams (#49 by @JordanMartinez)
 
 Bugfixes:
 
 Other improvements:
 - Bumped CI's node version to `lts/*` (#48 by @JordanMartinez)
 - Updated CI `actions/checkout` and `actions/setup-nodee` to `v3` (#48 by @JordanMartinez)
 - Format code via purs-tidy; enforce formatting via CI (#48 by @JordanMartinez)
+- Refactor tests using `passThrough` streams (#49 by @JordanMartinez)
 
 ## [v7.0.0](https://github.com/purescript-node/purescript-node-streams/releases/tag/v7.0.0) - 2022-04-29
 

bower.json

@@ -22,6 +22,7 @@
     "purescript-exceptions": "^6.0.0",
     "purescript-node-buffer": "^9.0.0",
     "purescript-nullable": "^6.0.0",
-    "purescript-prelude": "^6.0.0"
+    "purescript-prelude": "^6.0.0",
+    "purescript-node-event-emitter": "https://github.com/purescript-node/purescript-node-event-emitter.git#^3.0.0"
   }
 }

package.json

@@ -11,7 +11,6 @@
     "eslint": "^7.15.0",
     "pulp": "16.0.0-0",
     "purescript-psa": "^0.8.2",
-    "rimraf": "^3.0.2",
-    "stream-buffers": "^3.0.2"
+    "rimraf": "^3.0.2"
   }
 }

src/Node/Stream.js

@@ -1,67 +1,22 @@
-const _undefined = undefined;
-export { _undefined as undefined };
-
 export function setEncodingImpl(s) {
   return enc => () => {
     s.setEncoding(enc);
   };
 }
 
-export function readChunkImpl(Left) {
-  return Right => chunk => {
-    if (chunk instanceof Buffer) {
-      return Right(chunk);
-    } else if (typeof chunk === "string") {
-      return Left(chunk);
-    } else {
-      throw new Error(
-        "Node.Stream.readChunkImpl: Unrecognised " +
-          "chunk type; expected String or Buffer, got: " +
-          chunk
-      );
-    }
-  };
-}
-
-export function onDataEitherImpl(readChunk) {
-  return r => f => () => {
-    r.on("data", data => {
-      f(readChunk(data))();
-    });
-  };
-}
-
-export function onEnd(s) {
-  return f => () => {
-    s.on("end", f);
-  };
-}
-
-export function onFinish(s) {
-  return f => () => {
-    s.on("finish", f);
-  };
-}
-
-export function onReadable(s) {
-  return f => () => {
-    s.on("readable", f);
-  };
-}
-
-export function onError(s) {
-  return f => () => {
-    s.on("error", e => {
-      f(e)();
-    });
-  };
-}
-
-export function onClose(s) {
-  return f => () => {
-    s.on("close", f);
-  };
-}
+export const readChunkImpl = (useBuffer, useString, chunk) => {
+  if (chunk instanceof Buffer) {
+    return useBuffer(chunk);
+  } else if (typeof chunk === "string") {
+    return useString(chunk);
+  } else {
+    throw new Error(
+      "Node.Stream.readChunkImpl: Unrecognised " +
+        "chunk type; expected String or Buffer, got: " +
+        chunk
+    );
+  }
+};
 
 export function resume(s) {
   return () => {
@@ -91,16 +46,9 @@ export function unpipeAll(r) {
   return () => r.unpipe();
 }
 
-export function readImpl(readChunk) {
-  return Nothing => Just => r => s => () => {
-    const v = r.read(s);
-    if (v === null) {
-      return Nothing;
-    } else {
-      return Just(readChunk(v));
-    }
-  };
-}
+export const readImpl = (r) => r.read();
+
+export const readSizeImpl = (r, size) => r.read(size);
 
 export function writeImpl(w) {
   return chunk => done => () => w.write(chunk, null, done);