Add buffer support to split, join, replace and parse streams

src/index.spec.ts

@@ -495,6 +495,30 @@ test.cb("split() splits chunks using the specified separator", t => {
     source.push(null);
 });
 
+test.cb(
+    "split() splits utf-8 encoded buffers using the specified separator",
+    t => {
+        t.plan(3);
+        const expectedElements = ["a", "b", "c"];
+        let i = 0;
+        const through = split(",");
+        const buf = Buffer.from("a,b,c");
+        through
+            .on("data", element => {
+                expect(element).to.equal(expectedElements[i]);
+                i++;
+                t.pass();
+            })
+            .on("error", t.end)
+            .on("end", t.end);
+
+        for (let j = 0; j < buf.length; ++j) {
+            through.write(buf.slice(j, j + 1));
+        }
+        through.end();
+    },
+);
+
 test.cb("join() joins chunks using the specified separator", t => {
     t.plan(9);
     const source = new Readable({ objectMode: true });

src/index.ts

@@ -208,8 +208,10 @@ export function split(
     return new Transform({
         readableObjectMode: true,
         writableObjectMode: true,
-        async transform(chunk: string, encoding, callback) {
-            const splitted = chunk.split(separator);
+        transform(chunk: string | Buffer, encoding, callback) {
+            const asString =
+                chunk instanceof Buffer ? chunk.toString(encoding) : chunk;
+            const splitted = asString.split(separator);
             if (buffered.length > 0 && splitted.length > 1) {
                 splitted[0] = buffered.concat(splitted[0]);
                 buffered = "";
@@ -233,11 +235,13 @@ export function join(separator: string): NodeJS.ReadWriteStream {
     return new Transform({
         readableObjectMode: true,
         writableObjectMode: true,
-        async transform(chunk: string, encoding, callback) {
+        async transform(chunk: string | Buffer, encoding, callback) {
+            const asString =
+                chunk instanceof Buffer ? chunk.toString(encoding) : chunk;
             if (!isFirstChunk) {
                 this.push(separator);
             }
-            this.push(chunk);
+            this.push(asString);
             isFirstChunk = false;
             callback();
         },
@@ -257,8 +261,10 @@ export function replace(
     return new Transform({
         readableObjectMode: true,
         writableObjectMode: true,
-        transform(chunk: string, encoding, callback) {
-            callback(undefined, chunk.replace(searchValue, replaceValue));
+        transform(chunk: string | Buffer, encoding, callback) {
+            const asString =
+                chunk instanceof Buffer ? chunk.toString(encoding) : chunk;
+            callback(undefined, asString.replace(searchValue, replaceValue));
         },
     });
 }
@@ -270,10 +276,12 @@ export function parse(): NodeJS.ReadWriteStream {
     return new Transform({
         readableObjectMode: true,
         writableObjectMode: true,
-        async transform(chunk: string, encoding, callback) {
+        async transform(chunk: string | Buffer, encoding, callback) {
             try {
+                const asString =
+                    chunk instanceof Buffer ? chunk.toString(encoding) : chunk;
                 // Using await causes parsing errors to be emitted
-                callback(undefined, await JSON.parse(chunk));
+                callback(undefined, await JSON.parse(asString));
             } catch (err) {
                 callback(err);
             }