Add readRemaining and readRemainingWritten methods

index.d.ts

@@ -88,6 +88,10 @@ declare module "bytewriter" {
 
     // Return a new Buffer containing the bytes written so far
     readBuffer(length: number): Buffer
+    // Read the remaining bytes in the buffer from the current read index to end of underlying buffer
+    readRemaining(): Buffer
+    // Read the remaining bytes in the buffer from the current read index to the current write index
+    readRemainingWritten(): Buffer
 
     // Varints
 

src/browser.js

@@ -1,5 +1,5 @@
 const MAX_ALLOC_SIZE = 1024 * 1024 * 2 // 2MB
-const DEFAULT_ALLOC_SIZE = 10000
+const DEFAULT_ALLOC_SIZE = 10000 // 10 KB
 
 class ByteStream {
   constructor (buffer, maxSize) {
@@ -19,10 +19,11 @@ class ByteStream {
 
   resizeForWriteIfNeeded (bytes) {
     if ((this.writeOffset + bytes) > this.size) {
-      this.size *= 2
-      const newBuffer = new Uint8Array(this.size)
+      const allocSize = this.writeOffset
+      const newBuffer = new Uint8Array(allocSize)
       newBuffer.set(this.buffer)
       this.buffer = newBuffer
+      this.size = this.buffer.length
       this.view = new DataView(this.buffer.buffer)
     }
     if (this.size > this.guardLimit) throw new Error('Buffer size exceeded guard limit')
@@ -250,6 +251,18 @@ class ByteStream {
     return value
   }
 
+  readRemaining () {
+    const value = this.buffer.subarray(this.readOffset)
+    this.readOffset = this.buffer.length
+    return value
+  }
+
+  readRemainingWritten () {
+    const value = this.buffer.subarray(0, this.writeOffset)
+    this.readOffset = this.writeOffset
+    return value
+  }
+
   // Varints
   // Write a signed varint
   writeVarInt (value) {

src/node.js

@@ -1,5 +1,5 @@
 const MAX_ALLOC_SIZE = 1024 * 1024 * 2 // 2MB
-const DEFAULT_ALLOC_SIZE = 10000
+const DEFAULT_ALLOC_SIZE = 10000 // 10 KB
 
 class ByteStream {
   constructor (buffer, maxSize) {
@@ -13,9 +13,9 @@ class ByteStream {
 
   resizeForWriteIfNeeded (bytes) {
     if ((this.writeOffset + bytes) > this.size) {
-      this.size *= 2
-      const allocSize = this.size - this.writeOffset
+      const allocSize = this.writeOffset
       this.buffer = Buffer.concat([this.buffer, Buffer.allocUnsafe(allocSize)])
+      this.size = this.buffer.length
     }
     // Detect potential writing bugs
     if (this.size > this.guardLimit) throw new Error('Buffer size exceeded guard limit')
@@ -288,6 +288,18 @@ class ByteStream {
     return value
   }
 
+  readRemaining () {
+    const value = this.buffer.slice(this.readOffset)
+    this.readOffset = this.buffer.length
+    return value
+  }
+
+  readRemainingWritten () {
+    const value = this.buffer.slice(0, this.writeOffset)
+    this.readOffset = this.writeOffset
+    return value
+  }
+
   // Varints
 
   // Write a signed varint

test/basic.test.js

@@ -17,6 +17,7 @@ describe('basic tests', () => {
     stream.writeBuffer(Buffer.from([0x28, 0x29, 0x2a, 0x2b, 0x2c]))
     stream.readUInt8(0x01)
     stream.readUInt16BE(0x0203)
+    console.log('Buffer[24:]', stream.readRemainingWritten(), 'total:', stream.readRemaining())
     assert.strictEqual(stream.getBuffer().toString('hex'), '878c94208f9cb4e0b0c1c28408a6c8888102b6e8c881e3858b95283f9df3b63ff3c0ca4283de1b68656c6c6f20776f726c64210028292a2b2c')
     assert(ByteWriter.streamsEqual(stream, stream))
   })