Vendor dependencies

Let's see how I like this workflow.

vendor/wasm-bindgen/tests/wasm/option.js

@@ -0,0 +1,28 @@
+const wasm = require('wasm-bindgen-test.js');
+const assert = require('assert');
+
+class MyType {
+}
+
+exports.MyType = MyType;
+
+exports.take_none_byval = x => {
+    assert.strictEqual(x, undefined);
+};
+exports.take_some_byval = x => {
+    assert.ok(x !== null && x !== undefined);
+    assert.ok(x instanceof MyType);
+};
+exports.return_undef_byval = () => undefined;
+exports.return_null_byval = () => null;
+exports.return_some_byval = () => new MyType();
+
+exports.test_option_values = () => {
+    wasm.rust_take_none_byval(null);
+    wasm.rust_take_none_byval(undefined);
+    wasm.rust_take_some_byval(new MyType());
+    assert.strictEqual(wasm.rust_return_none_byval(), undefined);
+    const x = wasm.rust_return_some_byval();
+    assert.ok(x !== null && x !== undefined);
+    assert.ok(x instanceof MyType);
+};