1 files changed, 34 insertions, 0 deletions
diff --git a/std/_util/deep_assign.ts b/std/_util/deep_assign.ts
new file mode 100644
index 000000000..9034d89bd
--- /dev/null
+++ b/std/_util/deep_assign.ts
@@ -0,0 +1,34 @@
+// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
+import { assert } from "../testing/asserts.ts";
+
+export function deepAssign(
+  target: Record<string, unknown>,
+  ...sources: object[]
+): object | undefined {
+  for (let i = 0; i < sources.length; i++) {
+    const source = sources[i];
+    if (!source || typeof source !== `object`) {
+      return;
+    }
+    Object.entries(source).forEach(([key, value]: [string, unknown]): void => {
+      if (value instanceof Date) {
+        target[key] = new Date(value);
+        return;
+      }
+      if (!value || typeof value !== `object`) {
+        target[key] = value;
+        return;
+      }
+      if (Array.isArray(value)) {
+        target[key] = [];
+      }
+      // value is an Object
+      if (typeof target[key] !== `object` || !target[key]) {
+        target[key] = {};
+      }
+      assert(value);
+      deepAssign(target[key] as Record<string, unknown>, value);
+    });
+  }
+  return target;
+}