feat(NODE-7314): export byteUtils & add missing methods

[tadjik1]

Description

Summary of Changes

Added a compare(a: Uint8Array, b: Uint8Array): -1 | 0 | 1 byte utility that performs a lexicographical comparison of two byte arrays.
Added a concat(list: Uint8Array[]): Uint8Array utility.

And mark ByteUtils as public and experimental (similar as for NumberUtils).

Notes for Reviewers

• The comparison semantics for compare are intended to match typical lexicographical ordering used for binary data (byte-by-byte from index 0, with shorter equal-prefix arrays considered smaller).
• concat is implemented using .length on Uint8Array (number of elements), which matches the number of bytes for this typed array and keeps the implementation simple and explicit.
• Tests are designed to run in both Node and web environments, and assert the same outputs regardless of runtime.

What is the motivation for this change?

Release Highlight

ByteUtils added as a binary utillity

ByteUtils are now public and provide set of platform-agnostic tools to manipulate binary data (using Buffer in nodejs-compatible environments and fallback to Uint8Array).

Note

This feature is experimental and may change at any time

Double check the following

• Lint is passing (npm run check:lint)
• Self-review completed using the steps outlined here
• PR title follows the correct format: type(NODE-xxxx)[!]: description
  • Example: feat(NODE-1234)!: rewriting everything in coffeescript
• Changes are covered by tests
• New TODOs have a related JIRA ticket

[nbbeeken]

Looks great, one concern:

[baileympearson]

From the AC in the ticket:

.isBuffer
Does not exist; but we'll either want to remove usages of this from the driver (we'll need to evaluate on a case-by-case basis) or use isUint8Array, which exists in BSON. Maybe it makes sense to export isUint8Array from BSON too.

and

.from
The driver uses Buffer.from to convert the following to buffers:

• utf8 strings
• number arrays
• buffers
• base64 strings
  Byte utils supports converting base64 strings and number arrays to Uint8Arrays already. converting buffers to buffers can be done using isUint8Array and conditionally converting the string argument to a buffer if needed. We will need to add conversion of utf8 strings -> buffers to byte utils.

Have you given these APIs thought / are they not needed to remove dependence on the global Buffer object in the driver?

[tadjik1]

@baileympearson thanks for you comment. I have added missing methods: . isUint8Array (just export it as it's already implemented), as well as .fromUTF8 to support Buffer/uint8Array creation from strings.