.

node_modules/domexception/lib/utils.js

@@ -0,0 +1,86 @@
+"use strict";
+
+// Returns "Type(value) is Object" in ES terminology.
+function isObject(value) {
+  return typeof value === "object" && value !== null || typeof value === "function";
+}
+
+function getReferenceToBytes(bufferSource) {
+  // Node.js' Buffer does not allow subclassing for now, so we can get away with a prototype object check for perf.
+  if (Object.getPrototypeOf(bufferSource) === Buffer.prototype) {
+    return bufferSource;
+  }
+  if (bufferSource instanceof ArrayBuffer) {
+    return Buffer.from(bufferSource);
+  }
+  return Buffer.from(bufferSource.buffer, bufferSource.byteOffset, bufferSource.byteLength);
+}
+
+function getCopyToBytes(bufferSource) {
+  return Buffer.from(getReferenceToBytes(bufferSource));
+}
+
+function mixin(target, source) {
+  const keys = Object.getOwnPropertyNames(source);
+  for (let i = 0; i < keys.length; ++i) {
+    if (keys[i] in target) {
+      continue;
+    }
+
+    Object.defineProperty(target, keys[i], Object.getOwnPropertyDescriptor(source, keys[i]));
+  }
+}
+
+const wrapperSymbol = Symbol("wrapper");
+const implSymbol = Symbol("impl");
+const sameObjectCaches = Symbol("SameObject caches");
+
+function getSameObject(wrapper, prop, creator) {
+  if (!wrapper[sameObjectCaches]) {
+    wrapper[sameObjectCaches] = Object.create(null);
+  }
+
+  if (prop in wrapper[sameObjectCaches]) {
+    return wrapper[sameObjectCaches][prop];
+  }
+
+  wrapper[sameObjectCaches][prop] = creator();
+  return wrapper[sameObjectCaches][prop];
+}
+
+function wrapperForImpl(impl) {
+  return impl ? impl[wrapperSymbol] : null;
+}
+
+function implForWrapper(wrapper) {
+  return wrapper ? wrapper[implSymbol] : null;
+}
+
+function tryWrapperForImpl(impl) {
+  const wrapper = wrapperForImpl(impl);
+  return wrapper ? wrapper : impl;
+}
+
+function tryImplForWrapper(wrapper) {
+  const impl = implForWrapper(wrapper);
+  return impl ? impl : wrapper;
+}
+
+const iterInternalSymbol = Symbol("internal");
+const IteratorPrototype = Object.getPrototypeOf(Object.getPrototypeOf([][Symbol.iterator]()));
+
+module.exports = exports = {
+  isObject,
+  getReferenceToBytes,
+  getCopyToBytes,
+  mixin,
+  wrapperSymbol,
+  implSymbol,
+  getSameObject,
+  wrapperForImpl,
+  implForWrapper,
+  tryWrapperForImpl,
+  tryImplForWrapper,
+  iterInternalSymbol,
+  IteratorPrototype
+};