feat(ext/node): implement `node:v8` (#17806)

Closes https://github.com/denoland/deno/issues/17115 

Implements `cachedDataVersionTag` and `getHeapStatistics`. 

1 files changed, 58 insertions, 0 deletions

diff --git a/cli/tests/unit_node/v8_test.ts b/cli/tests/unit_node/v8_test.ts
new file mode 100644
index 000000000..ab1903596
--- /dev/null
+++ b/cli/tests/unit_node/v8_test.ts
@@ -0,0 +1,58 @@
+// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
+import {
+  cachedDataVersionTag,
+  getHeapStatistics,
+  setFlagsFromString,
+} from "node:v8";
+import {
+  assertEquals,
+  assertThrows,
+} from "../../../test_util/std/testing/asserts.ts";
+
+// https://github.com/nodejs/node/blob/a2bbe5ff216bc28f8dac1c36a8750025a93c3827/test/parallel/test-v8-version-tag.js#L6
+Deno.test({
+  name: "cachedDataVersionTag success",
+  fn() {
+    const tag = cachedDataVersionTag();
+    assertEquals(typeof tag, "number");
+    assertEquals(cachedDataVersionTag(), tag);
+  },
+});
+
+// https://github.com/nodejs/node/blob/a2bbe5ff216bc28f8dac1c36a8750025a93c3827/test/parallel/test-v8-stats.js#L6
+Deno.test({
+  name: "getHeapStatistics success",
+  fn() {
+    const s = getHeapStatistics();
+    const keys = [
+      "does_zap_garbage",
+      "external_memory",
+      "heap_size_limit",
+      "malloced_memory",
+      "number_of_detached_contexts",
+      "number_of_native_contexts",
+      "peak_malloced_memory",
+      "total_available_size",
+      "total_global_handles_size",
+      "total_heap_size",
+      "total_heap_size_executable",
+      "total_physical_size",
+      "used_global_handles_size",
+      "used_heap_size",
+    ];
+    assertEquals(Object.keys(s).sort(), keys);
+    for (const k of keys) {
+      assertEquals(
+        typeof (s as unknown as Record<string, unknown>)[k],
+        "number",
+      );
+    }
+  },
+});
+
+Deno.test({
+  name: "setFlagsFromString throws",
+  fn() {
+    assertThrows(() => setFlagsFromString("--allow_natives_syntax"));
+  },
+});