fix(assert,streams): handle SharedArrayBuffer being disabled in some browser context (#6856)

Per MDN spec SharedArrayBuffer require secure context and cross-origin isolated. When these contextes are not given then equal and new Buffer fail when called in the Web.

Author: lucsoft

assert/equal.ts

@@ -117,7 +117,10 @@ export function equal(a: unknown, b: unknown): boolean {
       if (a instanceof TypedArray) {
         return compareTypedArrays(a as TypedArray, b as TypedArray);
       }
-      if (a instanceof ArrayBuffer || a instanceof SharedArrayBuffer) {
+      if (
+        a instanceof ArrayBuffer ||
+        (globalThis.SharedArrayBuffer && a instanceof SharedArrayBuffer)
+      ) {
         return compareTypedArrays(
           new Uint8Array(a),
           new Uint8Array(b as ArrayBuffer | SharedArrayBuffer),

streams/buffer.ts

@@ -135,11 +135,8 @@ export class Buffer {
   constructor(ab?: ArrayBufferLike | ArrayLike<number>) {
     if (ab === undefined) {
       this.#buf = new Uint8Array(0);
-    } else if (ab instanceof SharedArrayBuffer) {
-      // Note: This is necessary to avoid type error
-      this.#buf = new Uint8Array(ab);
     } else {
-      this.#buf = new Uint8Array(ab);
+      this.#buf = new Uint8Array(ab as ArrayBuffer | SharedArrayBuffer);
     }
   }