Vendor dependencies

Let's see how I like this workflow.

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

@@ -0,0 +1,54 @@
+const wasm = require('wasm-bindgen-test.js');
+const assert = require('assert');
+
+exports.call_ok = function() {
+    assert.doesNotThrow(() => {
+        let five = wasm.return_ok();
+        assert.strictEqual(five, 5);
+    })
+}
+
+exports.call_err = function() {
+    assert.throws(() => wasm.return_err(), {
+        message: "MyError::Variant"
+    });
+}
+
+exports.call_make_an_error = function() {
+    assert.doesNotThrow(() => {
+        let e = wasm.make_an_error()
+        assert.strictEqual(e.message, "un-thrown error");
+    });
+}
+
+function check_inflight(struct) {
+    assert.strictEqual(struct.is_inflight(), false);
+}
+
+exports.all_struct_methods = function() {
+    let struct;
+    assert.throws(() => wasm.MyStruct.new_err(), {
+        message: "MyError::Variant"
+    });
+    assert.doesNotThrow(() => {
+        struct = wasm.MyStruct.new();
+    });
+    check_inflight(struct);
+    assert.doesNotThrow(() => {
+        let five = struct.return_ok();
+        assert.strictEqual(five, 5);
+    });
+    check_inflight(struct);
+    assert.throws(() => struct.return_err(), {
+        message: "MyError::Variant"
+    });
+    check_inflight(struct);
+}
+
+exports.call_return_string = function() {
+    assert.doesNotThrow(() => {
+        let ok = wasm.jserror_return_string();
+        assert.strictEqual(ok, "string here");
+    })
+}
+