feat: add structured cloning to Deno.core (#9458)

This commit adds two new "Deno.core" APIs:
- "Deno.core.serialize"
- "Deno.core.deserialize"

These APIs are used to provide structured cloning of values
and will be used for further web worker implementation.

Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>

1 files changed, 69 insertions, 0 deletions

diff --git a/core/serialize_deserialize_test.js b/core/serialize_deserialize_test.js
new file mode 100644
index 000000000..6368d56db
--- /dev/null
+++ b/core/serialize_deserialize_test.js
@@ -0,0 +1,69 @@
+// Copyright 2018-2021 the Deno authors. All rights reserved. MIT license.
+"use strict";
+
+function assert(cond) {
+  if (!cond) {
+    throw Error("assert");
+  }
+}
+
+function assertArrayEquals(a1, a2) {
+  if (a1.length !== a2.length) throw Error("assert");
+
+  for (const index in a1) {
+    if (a1[index] !== a2[index]) {
+      throw Error("assert");
+    }
+  }
+}
+
+function main() {
+  const emptyString = "";
+  const emptyStringSerialized = [34, 0];
+  assertArrayEquals(Deno.core.serialize(emptyString), emptyStringSerialized);
+  assert(
+    Deno.core.deserialize(new Uint8Array(emptyStringSerialized)) ===
+      emptyString,
+  );
+
+  const primitiveValueArray = ["test", "a", null, undefined];
+  // deno-fmt-ignore
+  const primitiveValueArraySerialized = [
+    65, 4, 34, 4, 116, 101, 115, 116,
+    34, 1, 97, 48, 95, 36, 0, 4,
+  ];
+  assertArrayEquals(
+    Deno.core.serialize(primitiveValueArray),
+    primitiveValueArraySerialized,
+  );
+
+  assertArrayEquals(
+    Deno.core.deserialize(
+      new Uint8Array(primitiveValueArraySerialized),
+    ),
+    primitiveValueArray,
+  );
+
+  const circularObject = { test: null, test2: "dd", test3: "aa" };
+  circularObject.test = circularObject;
+  // deno-fmt-ignore
+  const circularObjectSerialized = [
+    111, 34, 4, 116, 101, 115, 116, 94,
+    0, 34, 5, 116, 101, 115, 116, 50,
+    34, 2, 100, 100, 34, 5, 116, 101,
+    115, 116, 51, 34, 2, 97, 97, 123,
+    3,
+  ];
+
+  assertArrayEquals(
+    Deno.core.serialize(circularObject),
+    circularObjectSerialized,
+  );
+
+  const deserializedCircularObject = Deno.core.deserialize(
+    new Uint8Array(circularObjectSerialized),
+  );
+  assert(deserializedCircularObject.test == deserializedCircularObject);
+}
+
+main();