diff --git a/crates/js-sys/src/lib.rs b/crates/js-sys/src/lib.rs
index 146110a7..3dc777b6 100644
--- a/crates/js-sys/src/lib.rs
+++ b/crates/js-sys/src/lib.rs
@@ -125,6 +125,7 @@ extern "C" {
 // Array
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Array;
 
     /// Creates a new empty array
@@ -134,7 +135,7 @@ extern "C" {
     /// The `Array.from()` method creates a new, shallow-copied `Array` instance
     /// from an array-like or iterable object.
     #[wasm_bindgen(static_method_of = Array)]
-    pub fn from(val: JsValue) -> Array;
+    pub fn from(val: &JsValue) -> Array;
 
     /// The copyWithin() method shallow copies part of an array to another
     /// location in the same array and returns it, without modifying its size.
@@ -162,7 +163,7 @@ extern "C" {
     ///
     /// http://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/fill
     #[wasm_bindgen(method)]
-    pub fn fill(this: &Array, value: JsValue, start: u32, end: u32) -> Array;
+    pub fn fill(this: &Array, value: &JsValue, start: u32, end: u32) -> Array;
 
     /// The `filter()` method creates a new array with all elements that pass the
     /// test implemented by the provided function.
@@ -196,14 +197,14 @@ extern "C" {
     ///
     /// http://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/includes
     #[wasm_bindgen(method)]
-    pub fn includes(this: &Array, value: JsValue, from_index: i32) -> bool;
+    pub fn includes(this: &Array, value: &JsValue, from_index: i32) -> bool;
 
     /// The indexOf() method returns the first index at which a given element
     /// can be found in the array, or -1 if it is not present.
     ///
     /// http://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/indexOf
     #[wasm_bindgen(method, js_name = indexOf)]
-    pub fn index_of(this: &Array, value: JsValue, from_index: i32) -> i32;
+    pub fn index_of(this: &Array, value: &JsValue, from_index: i32) -> i32;
 
     /// The Array.isArray() method determines whether the passed value is an Array.
     ///
@@ -224,7 +225,7 @@ extern "C" {
     ///
     /// http://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/lastIndexOf
     #[wasm_bindgen(method, js_name = lastIndexOf)]
-    pub fn last_index_of(this: &Array, value: JsValue, from_index: i32) -> i32;
+    pub fn last_index_of(this: &Array, value: &JsValue, from_index: i32) -> i32;
 
     /// The length property of an object which is an instance of type Array
     /// sets or returns the number of elements in that array. The value is an
@@ -257,21 +258,21 @@ extern "C" {
     ///
     /// http://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/push
     #[wasm_bindgen(method)]
-    pub fn push(this: &Array, value: JsValue) -> u32;
+    pub fn push(this: &Array, value: &JsValue) -> u32;
 
     /// The reduce() method applies a function against an accumulator and each element in
     /// the array (from left to right) to reduce it to a single value.
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/Reduce
     #[wasm_bindgen(method)]
-    pub fn reduce(this: &Array, predicate: &mut FnMut(JsValue, JsValue, u32, Array) -> JsValue, initial_value: JsValue) -> JsValue;
+    pub fn reduce(this: &Array, predicate: &mut FnMut(JsValue, JsValue, u32, Array) -> JsValue, initial_value: &JsValue) -> JsValue;
 
     /// The reduceRight() method applies a function against an accumulator and each value
     /// of the array (from right-to-left) to reduce it to a single value.
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/ReduceRight
     #[wasm_bindgen(method, js_name = reduceRight)]
-    pub fn reduce_right(this: &Array, predicate: &mut FnMut(JsValue, JsValue, u32, Array) -> JsValue, initial_value: JsValue) -> JsValue;
+    pub fn reduce_right(this: &Array, predicate: &mut FnMut(JsValue, JsValue, u32, Array) -> JsValue, initial_value: &JsValue) -> JsValue;
 
     /// The reverse() method reverses an array in place. The first array
     /// element becomes the last, and the last array element becomes the first.
@@ -333,12 +334,13 @@ extern "C" {
     ///
     /// http://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/unshift
     #[wasm_bindgen(method)]
-    pub fn unshift(this: &Array, value: JsValue) -> u32;
+    pub fn unshift(this: &Array, value: &JsValue) -> u32;
 }
 
 // ArrayBuffer
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type ArrayBuffer;
 
     /// The `ArrayBuffer` object is used to represent a generic,
@@ -357,7 +359,7 @@ extern "C" {
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer/isView
     #[wasm_bindgen(static_method_of = ArrayBuffer, js_name = isView)]
-    pub fn is_view(value: JsValue) -> bool;
+    pub fn is_view(value: &JsValue) -> bool;
 
     /// The `slice()` method returns a new `ArrayBuffer` whose contents
     /// are a copy of this `ArrayBuffer`'s bytes from begin, inclusive,
@@ -377,6 +379,7 @@ extern "C" {
 // Array Iterator
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type ArrayIterator;
 
     /// The keys() method returns a new Array Iterator object that contains the
@@ -404,13 +407,14 @@ extern "C" {
 // Boolean
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Boolean;
 
     /// The `Boolean()` constructor creates an object wrapper for a boolean value.
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean
     #[wasm_bindgen(constructor)]
-    pub fn new(value: JsValue) -> Boolean;
+    pub fn new(value: &JsValue) -> Boolean;
 
     /// The `valueOf()` method returns the primitive value of a `Boolean` object.
     ///
@@ -422,6 +426,7 @@ extern "C" {
 // DataView
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type DataView;
 
     /// The `DataView` view provides a low-level interface for reading and
@@ -568,6 +573,7 @@ extern "C" {
 // Error
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Error;
 
     /// The Error constructor creates an error object.
@@ -605,13 +611,14 @@ extern "C" {
 // Float32Array
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Float32Array;
 
     /// The `Float32Array()` constructor creates an array of 32-bit floats.
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Float32Array
     #[wasm_bindgen(constructor)]
-    pub fn new(constructor_arg: JsValue) -> Float32Array;
+    pub fn new(constructor_arg: &JsValue) -> Float32Array;
 
     /// The fill() method fills all the elements of an array from a start index
     /// to an end index with a static value. The end index is not included.
@@ -656,13 +663,14 @@ extern "C" {
 // Float64Array
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Float64Array;
 
     /// The `Float64Array()` constructor creates an array of 64-bit floats.
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Float64Array
     #[wasm_bindgen(constructor)]
-    pub fn new(constructor_arg: JsValue) -> Float64Array;
+    pub fn new(constructor_arg: &JsValue) -> Float64Array;
 
     /// The fill() method fills all the elements of an array from a start index
     /// to an end index with a static value. The end index is not included.
@@ -707,6 +715,7 @@ extern "C" {
 // Function
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Function;
 
     /// The apply() method calls a function with a given this value, and arguments provided as an array
@@ -762,6 +771,7 @@ impl Function {
 // Generator
 #[wasm_bindgen]
 extern {
+    #[derive(Clone, Debug)]
     pub type Generator;
 
     /// The next() method returns an object with two properties done and value.
@@ -788,13 +798,14 @@ extern {
 // Int8Array
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Int8Array;
 
     /// The `Int8Array()` constructor creates an array of signed 8-bit integers.
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Int8Array
     #[wasm_bindgen(constructor)]
-    pub fn new(constructor_arg: JsValue) -> Int8Array;
+    pub fn new(constructor_arg: &JsValue) -> Int8Array;
 
     /// The fill() method fills all the elements of an array from a start index
     /// to an end index with a static value. The end index is not included.
@@ -839,13 +850,14 @@ extern "C" {
 // Int16Array
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Int16Array;
 
     /// The `Int16Array()` constructor creates an array of signed 16-bit integers.
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Int16Array
     #[wasm_bindgen(constructor)]
-    pub fn new(constructor_arg: JsValue) -> Int16Array;
+    pub fn new(constructor_arg: &JsValue) -> Int16Array;
 
     /// The fill() method fills all the elements of an array from a start index
     /// to an end index with a static value. The end index is not included.
@@ -890,13 +902,14 @@ extern "C" {
 // Int32Array
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Int32Array;
 
     /// The `Int32Array()` constructor creates an array of signed 32-bit integers.
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Int32Array
     #[wasm_bindgen(constructor)]
-    pub fn new(constructor_arg: JsValue) -> Int32Array;
+    pub fn new(constructor_arg: &JsValue) -> Int32Array;
 
     /// The fill() method fills all the elements of an array from a start index
     /// to an end index with a static value. The end index is not included.
@@ -941,6 +954,7 @@ extern "C" {
 // Map
 #[wasm_bindgen]
 extern {
+    #[derive(Clone, Debug)]
     pub type Map;
 
     /// The clear() method removes all elements from a Map object.
@@ -1001,6 +1015,7 @@ extern {
 // Map Iterator
 #[wasm_bindgen]
 extern {
+    #[derive(Clone, Debug)]
     pub type MapIterator;
 
     /// The entries() method returns a new Iterator object that contains
@@ -1029,6 +1044,7 @@ extern {
 // Math
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Math;
 
     /// The Math.abs() function returns the absolute value of a number, that is
@@ -1276,6 +1292,7 @@ extern "C" {
 // Number.
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Number;
 
     /// The Number.isFinite() method determines whether the passed value is a finite number.
@@ -1310,21 +1327,21 @@ extern "C" {
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number
     #[wasm_bindgen(constructor)]
-    pub fn new(value: JsValue) -> Number;
+    pub fn new(value: &JsValue) -> Number;
 
     /// The Number.parseInt() method parses a string argument and returns an
     /// integer of the specified radix or base.
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/parseInt
     #[wasm_bindgen(static_method_of = Number, js_name = parseInt)]
-    pub fn parse_int(text: &str, radix: u8) -> Number;
+    pub fn parse_int(text: &str, radix: u8) -> f64;
 
     /// The Number.parseFloat() method parses a string argument and returns a
     /// floating point number.
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/parseFloat
     #[wasm_bindgen(static_method_of = Number, js_name = parseFloat)]
-    pub fn parse_float(text: &str) -> Number;
+    pub fn parse_float(text: &str) -> f64;
 
     /// The toLocaleString() method returns a string with a language sensitive
     /// representation of this number.
@@ -1372,6 +1389,7 @@ extern "C" {
 // Date.
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Date;
 
     /// The getDate() method returns the day of the month for the
@@ -1497,7 +1515,7 @@ extern "C" {
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date
     #[wasm_bindgen(constructor)]
-    pub fn new(init: JsValue) -> Date;
+    pub fn new(init: &JsValue) -> Date;
 
     /// The `Date.now()` method returns the number of milliseconds
     /// elapsed since January 1, 1970 00:00:00 UTC.
@@ -1512,7 +1530,7 @@ extern "C" {
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/parse
     #[wasm_bindgen(static_method_of = Date)]
-    pub fn parse(date: JsString) -> f64;
+    pub fn parse(date: &JsString) -> f64;
 
     /// The setDate() method sets the day of the Date object relative to the beginning of the currently set month.
     ///
@@ -1644,7 +1662,7 @@ extern "C" {
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toLocaleDateString
     #[wasm_bindgen(method, js_name = toLocaleDateString)]
-    pub fn to_locale_date_string(this: &Date, locale: JsString, options: JsValue) -> JsString;
+    pub fn to_locale_date_string(this: &Date, locale: &JsString, options: &JsValue) -> JsString;
 
     /// The toLocaleString() method returns a string with a language sensitive
     /// representation of this date. The new locales and options arguments
@@ -1656,7 +1674,7 @@ extern "C" {
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toLocaleString
     #[wasm_bindgen(method, js_name = toLocaleString)]
-    pub fn to_locale_string(this: &Date, locale: JsString, options: JsValue) -> JsString;
+    pub fn to_locale_string(this: &Date, locale: &JsString, options: &JsValue) -> JsString;
 
     /// The toLocaleTimeString() method returns a string with a language sensitive
     /// representation of the time portion of this date. The new locales and options
@@ -1667,7 +1685,7 @@ extern "C" {
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toLocaleTimeString
     #[wasm_bindgen(method, js_name = toLocaleTimeString)]
-    pub fn to_locale_time_string(this: &Date, locale: JsString) -> JsString;
+    pub fn to_locale_time_string(this: &Date, locale: &JsString) -> JsString;
 
     /// The toString() method returns a string representing
     /// the specified Date object.
@@ -1710,6 +1728,7 @@ extern "C" {
 // Object.
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Object;
 
     /// The `Object.freeze()` method freezes an object: that is, prevents new
@@ -1731,7 +1750,7 @@ extern "C" {
     pub fn has_own_property(this: &Object, property: &JsValue) -> bool;
 
     /// The Object.is() method determines whether two values are the same value.
-    /// 
+    ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/is
     #[wasm_bindgen(static_method_of = Object)]
     pub fn is(value_1: &JsValue, value_2: &JsValue) -> bool;
@@ -1856,6 +1875,7 @@ impl Object {
 // Proxy
 #[wasm_bindgen]
 extern {
+    #[derive(Clone, Debug)]
     pub type Proxy;
 
     /// The [`Proxy`] object is used to define custom behavior for fundamental
@@ -1877,6 +1897,7 @@ extern {
 // Reflect
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Reflect;
 
     /// The static `Reflect.apply()` method calls a target function with
@@ -1988,6 +2009,7 @@ extern "C" {
 // Set
 #[wasm_bindgen]
 extern {
+    #[derive(Clone, Debug)]
     pub type Set;
 
     /// The `add()` method appends a new element with a specified value to the
@@ -2042,6 +2064,7 @@ extern {
 // SetIterator
 #[wasm_bindgen]
 extern {
+    #[derive(Clone, Debug)]
     pub type SetIterator;
 
     /// The `entries()` method returns a new Iterator object that contains an
@@ -2073,13 +2096,14 @@ extern {
 // Uint8Array
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Uint8Array;
 
     /// The `Uint8Array()` constructor creates an array of unsigned 8-bit integers.
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint8Array
     #[wasm_bindgen(constructor)]
-    pub fn new(constructor_arg: JsValue) -> Uint8Array;
+    pub fn new(constructor_arg: &JsValue) -> Uint8Array;
 
     /// The fill() method fills all the elements of an array from a start index
     /// to an end index with a static value. The end index is not included.
@@ -2124,6 +2148,7 @@ extern "C" {
 // Uint8ClampedArray
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Uint8ClampedArray;
 
     /// The `Uint8ClampedArray()` constructor creates an array of unsigned 8-bit integers clamped
@@ -2132,7 +2157,7 @@ extern "C" {
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint8ClampedArray
     #[wasm_bindgen(constructor)]
-    pub fn new(constructor_arg: JsValue) -> Uint8ClampedArray;
+    pub fn new(constructor_arg: &JsValue) -> Uint8ClampedArray;
 
     /// The fill() method fills all the elements of an array from a start index
     /// to an end index with a static value. The end index is not included.
@@ -2177,13 +2202,14 @@ extern "C" {
 // Uint16Array
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Uint16Array;
 
     /// The `Uint16Array()` constructor creates an array of unsigned 16-bit integers.
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint16Array
     #[wasm_bindgen(constructor)]
-    pub fn new(constructor_arg: JsValue) -> Uint16Array;
+    pub fn new(constructor_arg: &JsValue) -> Uint16Array;
 
     /// The fill() method fills all the elements of an array from a start index
     /// to an end index with a static value. The end index is not included.
@@ -2228,13 +2254,14 @@ extern "C" {
 // Uint32Array
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Uint32Array;
 
     /// The `Uint32Array()` constructor creates an array of unsigned 32-bit integers.
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint32Array
     #[wasm_bindgen(constructor)]
-    pub fn new(constructor_arg: JsValue) -> Uint32Array;
+    pub fn new(constructor_arg: &JsValue) -> Uint32Array;
 
     /// The fill() method fills all the elements of an array from a start index
     /// to an end index with a static value. The end index is not included.
@@ -2279,6 +2306,7 @@ extern "C" {
 // WeakMap
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type WeakMap;
 
     /// The [`WeakMap`] object is a collection of key/value pairs in which the
@@ -2294,7 +2322,7 @@ extern "C" {
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakMap/set
     #[wasm_bindgen(method, js_class = "WeakMap")]
-    pub fn set(this: &WeakMap, key: &Object, value: JsValue) -> WeakMap;
+    pub fn set(this: &WeakMap, key: &Object, value: &JsValue) -> WeakMap;
 
     /// The get() method returns a specified by key element
     /// from a [`WeakMap`] object.
@@ -2321,6 +2349,7 @@ extern "C" {
 // WeakSet
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type WeakSet;
 
     /// The `WeakSet` object lets you store weakly held objects in a collection.
@@ -2353,6 +2382,7 @@ extern "C" {
 // WebAssembly
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type WebAssembly;
 
     /// The `WebAssembly.validate()` function validates a given typed
@@ -2361,13 +2391,14 @@ extern "C" {
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WebAssembly/validate
     #[wasm_bindgen(static_method_of = WebAssembly, catch)]
-    pub fn validate(bufferSource: JsValue) -> Result<bool, JsValue>;
+    pub fn validate(bufferSource: &JsValue) -> Result<bool, JsValue>;
 }
 
 // JsString
 #[wasm_bindgen]
 extern "C" {
-    #[wasm_bindgen(js_name = JsString)]
+    #[wasm_bindgen(js_name = String)]
+    #[derive(Clone)]
     pub type JsString;
 
     /// The length property of a String object indicates the length of a string,
@@ -2657,6 +2688,7 @@ impl fmt::Debug for JsString {
 // Symbol
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Symbol;
 
     /// The `Symbol.hasInstance` well-known symbol is used to determine
@@ -2776,6 +2808,7 @@ extern "C" {
 // Intl
 #[wasm_bindgen]
 extern "C" {
+    #[derive(Clone, Debug)]
     pub type Intl;
 
     /// The `Intl.getCanonicalLocales()` method returns an array containing
diff --git a/crates/js-sys/tests/wasm/Array.rs b/crates/js-sys/tests/wasm/Array.rs
index d1536853..42c1ee7d 100644
--- a/crates/js-sys/tests/wasm/Array.rs
+++ b/crates/js-sys/tests/wasm/Array.rs
@@ -5,7 +5,7 @@ use js_sys::*;
 macro_rules! js_array {
     ($($e:expr),*) => ({
         let __x = Array::new();
-        $(__x.push(JsValue::from($e));)*
+        $(__x.push(&JsValue::from($e));)*
         __x
     })
 }
@@ -39,10 +39,10 @@ fn filter() {
 #[wasm_bindgen_test]
 fn index_of() {
     let chars = js_array!["a", "c", "x", "n"];
-    assert_eq!(chars.index_of("x".into(), 0), 2);
-    assert_eq!(chars.index_of("z".into(), 0), -1);
-    assert_eq!(chars.index_of("x".into(), -3), 2);
-    assert_eq!(chars.index_of("z".into(), -2), -1);
+    assert_eq!(chars.index_of(&"x".into(), 0), 2);
+    assert_eq!(chars.index_of(&"z".into(), 0), -1);
+    assert_eq!(chars.index_of(&"x".into(), -3), 2);
+    assert_eq!(chars.index_of(&"z".into(), -2), -1);
 }
 
 #[wasm_bindgen_test]
@@ -75,10 +75,10 @@ fn some() {
 #[wasm_bindgen_test]
 fn last_index_of() {
     let characters = js_array!["a", "x", "c", "x", "n"];
-    assert_eq!(characters.last_index_of("x".into(), 5), 3);
-    assert_eq!(characters.last_index_of("z".into(), 5), -1);
-    assert_eq!(characters.last_index_of("x".into(), 2), 1);
-    assert_eq!(characters.last_index_of("x".into(), 0), -1);
+    assert_eq!(characters.last_index_of(&"x".into(), 5), 3);
+    assert_eq!(characters.last_index_of(&"z".into(), 5), -1);
+    assert_eq!(characters.last_index_of(&"x".into(), 2), 1);
+    assert_eq!(characters.last_index_of(&"x".into(), 0), -1);
 }
 
 #[wasm_bindgen_test]
@@ -99,7 +99,7 @@ fn slice() {
 #[wasm_bindgen_test]
 fn fill() {
     let characters = js_array!["a", "c", "x", "n", 1, "8"];
-    let subset = characters.fill(0.into(), 0, 3);
+    let subset = characters.fill(&0.into(), 0, 3);
 
     assert_eq!(to_rust(&subset), array![0, 0, 0, "n", 1, "8"]);
 }
@@ -127,7 +127,7 @@ fn pop() {
 #[wasm_bindgen_test]
 fn push() {
     let characters = js_array![8, 5, 4, 3, 1, 2];
-    let length = characters.push("a".into());
+    let length = characters.push(&"a".into());
     assert_eq!(length, 7);
     assert_eq!(to_rust(&characters)[6], "a");
 }
@@ -151,7 +151,7 @@ fn shift() {
 #[wasm_bindgen_test]
 fn unshift() {
     let characters = js_array![8, 5, 4, 3, 1, 2];
-    let length = characters.unshift("abba".into());
+    let length = characters.unshift(&"abba".into());
 
     assert_eq!(length, 7);
     assert_eq!(to_rust(&characters)[0], "abba");
@@ -166,9 +166,9 @@ fn to_string() {
 #[wasm_bindgen_test]
 fn includes() {
     let characters = js_array![8, 5, 4, 3, 1, 2];
-    assert!(characters.includes(2.into(), 0));
-    assert!(!characters.includes(9.into(), 0));
-    assert!(!characters.includes(3.into(), 4));
+    assert!(characters.includes(&2.into(), 0));
+    assert!(!characters.includes(&9.into(), 0));
+    assert!(!characters.includes(&3.into(), 4));
 }
 
 #[wasm_bindgen_test]
@@ -225,7 +225,7 @@ fn reduce() {
                 format!("{}{}", &ac.as_string().unwrap(), &cr.as_string().unwrap())
                     .into()
             },
-            "".into(),
+            &"".into(),
         );
     assert_eq!(arr, "01234");
 }
@@ -238,7 +238,7 @@ fn reduce_right() {
                 format!("{}{}", &ac.as_string().unwrap(), &cr.as_string().unwrap())
                     .into()
             },
-            "".into(),
+            &"".into(),
         );
     assert_eq!(arr, "43210");
 }
@@ -255,7 +255,7 @@ fn find_index() {
 
 #[wasm_bindgen_test]
 fn to_locale_string() {
-    let output = js_array![1, "a", Date::new("21 Dec 1997 14:12:00 UTC".into())]
+    let output = js_array![1, "a", Date::new(&"21 Dec 1997 14:12:00 UTC".into())]
         .to_locale_string(&"en".into(), &JsValue::undefined());
     assert!(String::from(output).len() > 0);
 }
diff --git a/crates/js-sys/tests/wasm/ArrayBuffer.rs b/crates/js-sys/tests/wasm/ArrayBuffer.rs
index f803698f..904221ff 100644
--- a/crates/js-sys/tests/wasm/ArrayBuffer.rs
+++ b/crates/js-sys/tests/wasm/ArrayBuffer.rs
@@ -11,8 +11,8 @@ fn new() {
 
 #[wasm_bindgen_test]
 fn is_view() {
-    let x = Uint8Array::new(JsValue::from(42));
-    assert!(ArrayBuffer::is_view(JsValue::from(x)));
+    let x = Uint8Array::new(&JsValue::from(42));
+    assert!(ArrayBuffer::is_view(&JsValue::from(x)));
 }
 
 #[test]
diff --git a/crates/js-sys/tests/wasm/ArrayIterator.rs b/crates/js-sys/tests/wasm/ArrayIterator.rs
index 1304b551..0554e156 100644
--- a/crates/js-sys/tests/wasm/ArrayIterator.rs
+++ b/crates/js-sys/tests/wasm/ArrayIterator.rs
@@ -5,13 +5,13 @@ use js_sys::*;
 #[wasm_bindgen_test]
 fn keys() {
     let array = Array::new();
-    array.push(JsValue::from(1));
-    array.push(JsValue::from(2));
-    array.push(JsValue::from(3));
-    array.push(JsValue::from(4));
-    array.push(JsValue::from(5));
+    array.push(&JsValue::from(1));
+    array.push(&JsValue::from(2));
+    array.push(&JsValue::from(3));
+    array.push(&JsValue::from(4));
+    array.push(&JsValue::from(5));
 
-    let new_array = Array::from(array.keys().into());
+    let new_array = Array::from(&array.keys().into());
 
     let mut result = Vec::new();
     new_array.for_each(&mut |i, _, _| result.push(i.as_f64().unwrap()));
@@ -21,13 +21,13 @@ fn keys() {
 #[wasm_bindgen_test]
 fn entries() {
     let array = Array::new();
-    array.push(JsValue::from(1));
-    array.push(JsValue::from(2));
-    array.push(JsValue::from(3));
-    array.push(JsValue::from(4));
-    array.push(JsValue::from(5));
+    array.push(&JsValue::from(1));
+    array.push(&JsValue::from(2));
+    array.push(&JsValue::from(3));
+    array.push(&JsValue::from(4));
+    array.push(&JsValue::from(5));
 
-    let new_array = Array::from(array.entries().into());
+    let new_array = Array::from(&array.entries().into());
 
     new_array.for_each(&mut |a, i, _| {
         assert!(a.is_object());
diff --git a/crates/js-sys/tests/wasm/Boolean.rs b/crates/js-sys/tests/wasm/Boolean.rs
index c9f21759..6f0befaa 100644
--- a/crates/js-sys/tests/wasm/Boolean.rs
+++ b/crates/js-sys/tests/wasm/Boolean.rs
@@ -4,10 +4,10 @@ use js_sys::*;
 
 #[wasm_bindgen_test]
 fn new_undefined() {
-    assert_eq!(Boolean::new(JsValue::undefined()).value_of(), false);
+    assert_eq!(Boolean::new(&JsValue::undefined()).value_of(), false);
 }
 
 #[wasm_bindgen_test]
 fn new_truely() {
-    assert_eq!(Boolean::new(JsValue::from("foo")).value_of(), true);
+    assert_eq!(Boolean::new(&JsValue::from("foo")).value_of(), true);
 }
diff --git a/crates/js-sys/tests/wasm/DataView.rs b/crates/js-sys/tests/wasm/DataView.rs
index 9dd8baf4..b7d952ae 100644
--- a/crates/js-sys/tests/wasm/DataView.rs
+++ b/crates/js-sys/tests/wasm/DataView.rs
@@ -4,7 +4,7 @@ use js_sys::*;
 
 #[wasm_bindgen_test]
 fn test() {
-    let bytes = Int8Array::new(JsValue::from(10));
+    let bytes = Int8Array::new(&JsValue::from(10));
 
     // TODO: figure out how to do `bytes[2] = 2`
     bytes.subarray(2, 3).fill(2, 0, 1);
diff --git a/crates/js-sys/tests/wasm/Date.rs b/crates/js-sys/tests/wasm/Date.rs
index 3c094fc3..7e8c8b16 100644
--- a/crates/js-sys/tests/wasm/Date.rs
+++ b/crates/js-sys/tests/wasm/Date.rs
@@ -4,20 +4,20 @@ use js_sys::*;
 
 #[wasm_bindgen_test]
 fn get_date() {
-    let date = Date::new("August 19, 1975 23:15:30".into());
+    let date = Date::new(&"August 19, 1975 23:15:30".into());
     assert_eq!(date.get_date(), 19);
 }
 
 #[wasm_bindgen_test]
 fn get_day() {
-    let date = Date::new("August 19, 1975 23:15:30".into());
+    let date = Date::new(&"August 19, 1975 23:15:30".into());
     assert_eq!(date.get_day(), 2);
 }
 
 #[wasm_bindgen_test]
 fn get_full_year() {
-    let date = Date::new("July 20, 1969 00:20:18".into());
-    let abbr = Date::new("Thu, 06 Sep 12 00:00:00".into());
+    let date = Date::new(&"July 20, 1969 00:20:18".into());
+    let abbr = Date::new(&"Thu, 06 Sep 12 00:00:00".into());
 
     assert_eq!(date.get_full_year(), 1969);
     assert_eq!(abbr.get_full_year(), 2012);
@@ -25,14 +25,14 @@ fn get_full_year() {
 
 #[wasm_bindgen_test]
 fn get_hours() {
-    let date = Date::new("March 13, 08 04:20".into());
+    let date = Date::new(&"March 13, 08 04:20".into());
     assert_eq!(date.get_hours(), 4);
 }
 
 #[wasm_bindgen_test]
 fn get_milliseconds() {
-    let date = Date::new("July 20, 69 00:20:18".into());
-    let ms = Date::new("July 20, 69 00:20:18:123".into());
+    let date = Date::new(&"July 20, 69 00:20:18".into());
+    let ms = Date::new(&"July 20, 69 00:20:18:123".into());
 
     assert_eq!(date.get_milliseconds(), 0);
     assert_eq!(ms.get_milliseconds(), 123);
@@ -40,51 +40,51 @@ fn get_milliseconds() {
 
 #[wasm_bindgen_test]
 fn get_minutes() {
-    let date = Date::new("March 13, 08 04:20".into());
+    let date = Date::new(&"March 13, 08 04:20".into());
 
     assert_eq!(date.get_minutes(), 20);
 }
 
 #[wasm_bindgen_test]
 fn get_month() {
-    let date = Date::new("July 20, 69 00:20:18".into());
+    let date = Date::new(&"July 20, 69 00:20:18".into());
 
     assert_eq!(date.get_month(), 6);
 }
 
 #[wasm_bindgen_test]
 fn get_seconds() {
-    let date = Date::new("July 20, 69 00:20:18".into());
+    let date = Date::new(&"July 20, 69 00:20:18".into());
 
     assert_eq!(date.get_seconds(), 18);
 }
 
 #[wasm_bindgen_test]
 fn get_time() {
-    let date = Date::new("July 20, 69 00:20:18 GMT+00:00".into());
+    let date = Date::new(&"July 20, 69 00:20:18 GMT+00:00".into());
 
     assert_eq!(date.get_time(), -14254782000.0);
 }
 
 #[wasm_bindgen_test]
 fn get_timezone_offset() {
-    let date1 = Date::new("August 19, 1975 23:15:30 GMT+07:00".into());
-    let date2 = Date::new("August 19, 1975 23:15:30 GMT-02:00".into());
+    let date1 = Date::new(&"August 19, 1975 23:15:30 GMT+07:00".into());
+    let date2 = Date::new(&"August 19, 1975 23:15:30 GMT-02:00".into());
     assert_eq!(date1.get_timezone_offset(), date2.get_timezone_offset());
 }
 
 #[wasm_bindgen_test]
 fn get_utc_date() {
-    let date1 = Date::new("August 19, 1975 23:15:30 GMT+11:00".into());
-    let date2 = Date::new("August 19, 1975 23:15:30 GMT-11:00".into());
+    let date1 = Date::new(&"August 19, 1975 23:15:30 GMT+11:00".into());
+    let date2 = Date::new(&"August 19, 1975 23:15:30 GMT-11:00".into());
     assert_eq!(date1.get_utc_date(), 19);
     assert_eq!(date2.get_utc_date(), 20);
 }
 
 #[wasm_bindgen_test]
 fn get_utc_day() {
-    let date1 = Date::new("August 19, 1975 23:15:30 GMT+11:00".into());
-    let date2 = Date::new("August 19, 1975 23:15:30 GMT-11:00".into());
+    let date1 = Date::new(&"August 19, 1975 23:15:30 GMT+11:00".into());
+    let date2 = Date::new(&"August 19, 1975 23:15:30 GMT-11:00".into());
 
     assert_eq!(date1.get_utc_day(), 2);
     assert_eq!(date2.get_utc_day(), 3);
@@ -92,16 +92,16 @@ fn get_utc_day() {
 
 #[wasm_bindgen_test]
 fn get_utc_full_year() {
-    let date1 = Date::new("December 31, 1975, 23:15:30 GMT+11:00".into());
-    let date2 = Date::new("December 31, 1975, 23:15:30 GMT-11:00".into());
+    let date1 = Date::new(&"December 31, 1975, 23:15:30 GMT+11:00".into());
+    let date2 = Date::new(&"December 31, 1975, 23:15:30 GMT-11:00".into());
     assert_eq!(date1.get_utc_full_year(), 1975);
     assert_eq!(date2.get_utc_full_year(), 1976);
 }
 
 #[wasm_bindgen_test]
 fn get_utc_hours() {
-    let date1 = Date::new("December 31, 1975, 23:15:30 GMT+11:00".into());
-    let date2 = Date::new("December 31, 1975, 23:15:30 GMT-11:00".into());
+    let date1 = Date::new(&"December 31, 1975, 23:15:30 GMT+11:00".into());
+    let date2 = Date::new(&"December 31, 1975, 23:15:30 GMT-11:00".into());
 
     assert_eq!(date1.get_utc_hours(), 12);
     assert_eq!(date2.get_utc_hours(), 10);
@@ -109,22 +109,22 @@ fn get_utc_hours() {
 
 #[wasm_bindgen_test]
 fn get_utc_milliseconds() {
-    let date = Date::new("2018-01-02T03:04:05.678Z".into());
+    let date = Date::new(&"2018-01-02T03:04:05.678Z".into());
     assert_eq!(date.get_utc_milliseconds(), 678);
 }
 
 #[wasm_bindgen_test]
 fn get_utc_minutes() {
-    let date1 = Date::new("1 January 2000 03:15:30 GMT+07:00".into());
-    let date2 = Date::new("1 January 2000 03:15:30 GMT+03:30".into());
+    let date1 = Date::new(&"1 January 2000 03:15:30 GMT+07:00".into());
+    let date2 = Date::new(&"1 January 2000 03:15:30 GMT+03:30".into());
     assert_eq!(date1.get_utc_minutes(), 15);
     assert_eq!(date2.get_utc_minutes(), 45);
 }
 
 #[wasm_bindgen_test]
 fn get_utc_month() {
-    let date1 = Date::new("December 31, 1975, 23:15:30 GMT+11:00".into());
-    let date2 = Date::new("December 31, 1975, 23:15:30 GMT-11:00".into());
+    let date1 = Date::new(&"December 31, 1975, 23:15:30 GMT+11:00".into());
+    let date2 = Date::new(&"December 31, 1975, 23:15:30 GMT-11:00".into());
 
     assert_eq!(date1.get_utc_month(), 11);
     assert_eq!(date2.get_utc_month(), 0);
@@ -132,14 +132,14 @@ fn get_utc_month() {
 
 #[wasm_bindgen_test]
 fn get_utc_seconds() {
-    let date = Date::new("July 20, 1969, 20:18:04 UTC".into());
+    let date = Date::new(&"July 20, 1969, 20:18:04 UTC".into());
 
     assert_eq!(date.get_utc_seconds(), 4);
 }
 
 #[wasm_bindgen_test]
 fn new() {
-    assert!(JsValue::from(Date::new(JsValue::undefined())).is_object());
+    assert!(JsValue::from(Date::new(&JsValue::undefined())).is_object());
 }
 
 #[wasm_bindgen_test]
@@ -149,8 +149,8 @@ fn now() {
 
 #[wasm_bindgen_test]
 fn parse() {
-    let date = Date::parse("04 Dec 1995 00:12:00 GMT".into());
-    let zero = Date::parse("01 Jan 1970 00:00:00 GMT".into());
+    let date = Date::parse(&"04 Dec 1995 00:12:00 GMT".into());
+    let zero = Date::parse(&"01 Jan 1970 00:00:00 GMT".into());
 
     assert_eq!(date, 818035920000.0);
     assert_eq!(zero, 0.0);
@@ -158,8 +158,8 @@ fn parse() {
 
 #[wasm_bindgen_test]
 fn set_date() {
-    let event1 = Date::new("August 19, 1975 23:15:30".into());
-    let event2 = Date::new("August 24, 1975 23:15:30".into());
+    let event1 = Date::new(&"August 19, 1975 23:15:30".into());
+    let event2 = Date::new(&"August 24, 1975 23:15:30".into());
 
     let ms = event1.set_date(24);
 
@@ -170,8 +170,8 @@ fn set_date() {
 
 #[wasm_bindgen_test]
 fn set_full_year() {
-    let event1 = Date::new("August 19, 1975 23:15:30".into());
-    let event2 = Date::new("August 19, 1976 23:15:30".into());
+    let event1 = Date::new(&"August 19, 1975 23:15:30".into());
+    let event2 = Date::new(&"August 19, 1976 23:15:30".into());
 
     let ms = event1.set_full_year(1976);
 
@@ -182,8 +182,8 @@ fn set_full_year() {
 
 #[wasm_bindgen_test]
 fn set_hours() {
-    let event1 = Date::new("August 19, 1975 23:15:30".into());
-    let event2 = Date::new("August 19, 1975 20:15:30".into());
+    let event1 = Date::new(&"August 19, 1975 23:15:30".into());
+    let event2 = Date::new(&"August 19, 1975 20:15:30".into());
 
     let ms = event1.set_hours(20);
 
@@ -194,7 +194,7 @@ fn set_hours() {
 
 #[wasm_bindgen_test]
 fn set_milliseconds() {
-    let event = Date::new("August 19, 1975 23:15:30".into());
+    let event = Date::new(&"August 19, 1975 23:15:30".into());
 
     let ms = event.set_milliseconds(456);
 
@@ -204,8 +204,8 @@ fn set_milliseconds() {
 
 #[wasm_bindgen_test]
 fn set_minutes() {
-    let event1 = Date::new("August 19, 1975 23:15:30".into());
-    let event2 = Date::new("August 19, 1975 23:45:30".into());
+    let event1 = Date::new(&"August 19, 1975 23:15:30".into());
+    let event2 = Date::new(&"August 19, 1975 23:45:30".into());
 
     let ms = event1.set_minutes(45);
 
@@ -216,8 +216,8 @@ fn set_minutes() {
 
 #[wasm_bindgen_test]
 fn set_month() {
-    let event1 = Date::new("August 19, 1975 23:15:30".into());
-    let event2 = Date::new("April 19, 1975 23:15:30".into());
+    let event1 = Date::new(&"August 19, 1975 23:15:30".into());
+    let event2 = Date::new(&"April 19, 1975 23:15:30".into());
 
     let ms = event1.set_month(3);
 
@@ -228,8 +228,8 @@ fn set_month() {
 
 #[wasm_bindgen_test]
 fn set_seconds() {
-    let event1 = Date::new("August 19, 1975 23:15:30".into());
-    let event2 = Date::new("August 19, 1975 23:15:42".into());
+    let event1 = Date::new(&"August 19, 1975 23:15:30".into());
+    let event2 = Date::new(&"August 19, 1975 23:15:42".into());
 
     let ms = event1.set_seconds(42);
 
@@ -240,8 +240,8 @@ fn set_seconds() {
 
 #[wasm_bindgen_test]
 fn set_time() {
-    let event1 = Date::new("July 1, 1999".into());
-    let event2 = Date::new(JsValue::undefined());
+    let event1 = Date::new(&"July 1, 1999".into());
+    let event2 = Date::new(&JsValue::undefined());
 
     let ms = event2.set_time(event1.get_time());
 
@@ -251,8 +251,8 @@ fn set_time() {
 
 #[wasm_bindgen_test]
 fn set_utc_date() {
-    let event1 = Date::new("August 19, 1975 23:15:30 GMT-3:00".into());
-    let event2 = Date::new("August 19, 1975 02:15:30 GMT".into());
+    let event1 = Date::new(&"August 19, 1975 23:15:30 GMT-3:00".into());
+    let event2 = Date::new(&"August 19, 1975 02:15:30 GMT".into());
 
     let ms = event1.set_utc_date(19);
 
@@ -263,8 +263,8 @@ fn set_utc_date() {
 
 #[wasm_bindgen_test]
 fn set_utc_full_year() {
-    let event1 = Date::new("December 31, 1975 23:15:30 GMT-3:00".into());
-    let event2 = Date::new("January 01, 1975 02:15:30 GMT".into());
+    let event1 = Date::new(&"December 31, 1975 23:15:30 GMT-3:00".into());
+    let event2 = Date::new(&"January 01, 1975 02:15:30 GMT".into());
 
     let ms = event1.set_utc_full_year(1975);
 
@@ -275,8 +275,8 @@ fn set_utc_full_year() {
 
 #[wasm_bindgen_test]
 fn set_utc_hours() {
-    let event1 = Date::new("August 19, 1975 23:15:30 GMT-3:00".into());
-    let event2 = Date::new("August 20, 1975 23:15:30 GMT".into());
+    let event1 = Date::new(&"August 19, 1975 23:15:30 GMT-3:00".into());
+    let event2 = Date::new(&"August 20, 1975 23:15:30 GMT".into());
 
     let ms = event1.set_utc_hours(23);
 
@@ -287,8 +287,8 @@ fn set_utc_hours() {
 
 #[wasm_bindgen_test]
 fn set_utc_milliseconds() {
-    let event1 = Date::new("August 19, 1975 23:15:30 GMT-3:00".into());
-    let event2 = Date::new("August 20, 1975 02:15:30.420Z GMT".into());
+    let event1 = Date::new(&"August 19, 1975 23:15:30 GMT-3:00".into());
+    let event2 = Date::new(&"August 20, 1975 02:15:30.420Z GMT".into());
 
     let ms = event1.set_utc_milliseconds(420);
 
@@ -299,8 +299,8 @@ fn set_utc_milliseconds() {
 
 #[wasm_bindgen_test]
 fn set_utc_minutes() {
-    let event1 = Date::new("December 31, 1975, 23:15:30 GMT-3:00".into());
-    let event2 = Date::new("January 01, 1976 02:25:30 GMT".into());
+    let event1 = Date::new(&"December 31, 1975, 23:15:30 GMT-3:00".into());
+    let event2 = Date::new(&"January 01, 1976 02:25:30 GMT".into());
 
     let ms = event1.set_utc_minutes(25);
 
@@ -311,8 +311,8 @@ fn set_utc_minutes() {
 
 #[wasm_bindgen_test]
 fn set_utc_month() {
-    let event1 = Date::new("December 31, 1975 23:15:30 GMT-3:00".into());
-    let event2 = Date::new("December 01, 1976 02:15:30 GMT".into());
+    let event1 = Date::new(&"December 31, 1975 23:15:30 GMT-3:00".into());
+    let event2 = Date::new(&"December 01, 1976 02:15:30 GMT".into());
 
     let ms = event1.set_utc_month(11);
 
@@ -323,8 +323,8 @@ fn set_utc_month() {
 
 #[wasm_bindgen_test]
 fn set_utc_seconds() {
-    let event1 = Date::new("December 31, 1975 23:15:30 GMT-3:00".into());
-    let event2 = Date::new("January 01, 1976 02:15:39 GMT".into());
+    let event1 = Date::new(&"December 31, 1975 23:15:30 GMT-3:00".into());
+    let event2 = Date::new(&"January 01, 1976 02:15:39 GMT".into());
 
     let ms = event1.set_utc_seconds(39);
 
@@ -335,63 +335,63 @@ fn set_utc_seconds() {
 
 #[wasm_bindgen_test]
 fn to_date_string() {
-    let date = Date::new("05 October 2011 14:48 UTC".into());
+    let date = Date::new(&"05 October 2011 14:48 UTC".into());
     assert_eq!(JsValue::from(date.to_date_string()), "Wed Oct 05 2011");
 }
 
 #[wasm_bindgen_test]
 fn to_iso_string() {
-    let date = Date::new("05 October 2011 14:48 UTC".into());
+    let date = Date::new(&"05 October 2011 14:48 UTC".into());
     assert_eq!(JsValue::from(date.to_iso_string()), "2011-10-05T14:48:00.000Z");
 }
 
 #[wasm_bindgen_test]
 fn to_json() {
-    let date = Date::new("August 19, 1975 23:15:30 UTC".into());
+    let date = Date::new(&"August 19, 1975 23:15:30 UTC".into());
 
     assert_eq!(JsValue::from(date.to_json()), "1975-08-19T23:15:30.000Z");
 }
 
 #[wasm_bindgen_test]
 fn to_locale_date_string() {
-    let date = Date::new("August 19, 1975 23:15:30 UTC".into());
-    let s = date.to_locale_date_string("de-DE".into(), JsValue::undefined());
+    let date = Date::new(&"August 19, 1975 23:15:30 UTC".into());
+    let s = date.to_locale_date_string(&"de-DE".into(), &JsValue::undefined());
     assert!(s.length() > 0);
 }
 
 #[wasm_bindgen_test]
 fn to_locale_string() {
-    let date = Date::new("August 19, 1975 23:15:30 UTC".into());
-    let s = date.to_locale_string("de-DE".into(), JsValue::undefined());
+    let date = Date::new(&"August 19, 1975 23:15:30 UTC".into());
+    let s = date.to_locale_string(&"de-DE".into(), &JsValue::undefined());
     assert!(s.length() > 0);
 }
 
 #[wasm_bindgen_test]
 fn to_locale_time_string() {
-    let date = Date::new("August 19, 1975 23:15:30".into());
+    let date = Date::new(&"August 19, 1975 23:15:30".into());
     assert_eq!(
-        JsValue::from(date.to_locale_time_string("en-US".into())),
+        JsValue::from(date.to_locale_time_string(&"en-US".into())),
         "11:15:30 PM",
     );
 }
 
 #[wasm_bindgen_test]
 fn to_string() {
-    let date = Date::new("August 19, 1975 23:15:30".into());
+    let date = Date::new(&"August 19, 1975 23:15:30".into());
     let s = JsValue::from(date.to_string()).as_string().unwrap();
     assert_eq!(&s[0..15], "Tue Aug 19 1975");
 }
 
 #[wasm_bindgen_test]
 fn to_time_string() {
-    let date = Date::new("August 19, 1975 23:15:30".into());
+    let date = Date::new(&"August 19, 1975 23:15:30".into());
     let s = JsValue::from(date.to_time_string()).as_string().unwrap();
     assert_eq!(&s[0..8], "23:15:30");
 }
 
 #[wasm_bindgen_test]
 fn to_utc_string() {
-    let date = Date::new("14 Jun 2017 00:00:00 PDT".into());
+    let date = Date::new(&"14 Jun 2017 00:00:00 PDT".into());
     let s = JsValue::from(date.to_utc_string()).as_string().unwrap();
     assert_eq!(s, "Wed, 14 Jun 2017 07:00:00 GMT");
 }
@@ -403,6 +403,6 @@ fn utc() {
 
 #[wasm_bindgen_test]
 fn value_of() {
-    let date = Date::new(Date::utc(2018f64, 6f64).into());
+    let date = Date::new(&Date::utc(2018f64, 6f64).into());
     assert_eq!(date.value_of(), 1530403200000.0);
 }
diff --git a/crates/js-sys/tests/wasm/Function.rs b/crates/js-sys/tests/wasm/Function.rs
index e2449a7e..999debfd 100644
--- a/crates/js-sys/tests/wasm/Function.rs
+++ b/crates/js-sys/tests/wasm/Function.rs
@@ -17,16 +17,16 @@ extern {
 #[wasm_bindgen_test]
 fn apply() {
     let args = Array::new();
-    args.push(1.into());
-    args.push(2.into());
-    args.push(3.into());
+    args.push(&1.into());
+    args.push(&2.into());
+    args.push(&3.into());
     assert_eq!(MAX.apply(&JsValue::undefined(), &args).unwrap(), 3);
 
     let arr = JsValue::from(Array::new());
     let args = Array::new();
-    args.push(1.into());
+    args.push(&1.into());
     ARRAY_PROTOTYPE.push().apply(&arr, &args).unwrap();
-    assert_eq!(Array::from(arr).length(), 1);
+    assert_eq!(Array::from(&arr).length(), 1);
 }
 
 #[wasm_bindgen(module = "tests/wasm/Function.js", version = "*")]
diff --git a/crates/js-sys/tests/wasm/Intl.rs b/crates/js-sys/tests/wasm/Intl.rs
index 208dd6a2..a739656b 100644
--- a/crates/js-sys/tests/wasm/Intl.rs
+++ b/crates/js-sys/tests/wasm/Intl.rs
@@ -5,8 +5,8 @@ use js_sys::*;
 #[wasm_bindgen_test]
 fn get_canonical_locales() {
     let locales = Array::new();
-    locales.push("EN-US".into());
-    locales.push("Fr".into());
+    locales.push(&"EN-US".into());
+    locales.push(&"Fr".into());
     let locales = JsValue::from(locales);
     let canonical_locales = Intl::get_canonical_locales(&locales);
     assert_eq!(canonical_locales.length(), 2);
diff --git a/crates/js-sys/tests/wasm/Number.rs b/crates/js-sys/tests/wasm/Number.rs
index 93e5b012..fee72abc 100644
--- a/crates/js-sys/tests/wasm/Number.rs
+++ b/crates/js-sys/tests/wasm/Number.rs
@@ -50,7 +50,7 @@ fn is_safe_integer() {
 
 #[wasm_bindgen_test]
 fn new() {
-    let n = Number::new(JsValue::from(42));
+    let n = Number::new(&JsValue::from(42));
     let v = JsValue::from(n);
     assert!(v.is_object());
     assert_eq!(Number::from(v).value_of(), 42.);
@@ -58,17 +58,17 @@ fn new() {
 
 #[wasm_bindgen_test]
 fn parse_int_float() {
-    assert_eq!(Number::parse_int("42", 10).value_of(), 42.);
-    assert_eq!(Number::parse_int("42", 16).value_of(), 66.); // 0x42 == 66
-    assert!(Number::parse_int("invalid int", 10).value_of().is_nan());
+    assert_eq!(Number::parse_int("42", 10), 42.);
+    assert_eq!(Number::parse_int("42", 16), 66.); // 0x42 == 66
+    assert!(Number::parse_int("invalid int", 10).is_nan());
 
-    assert_eq!(Number::parse_float("123456.789").value_of(), 123456.789);
-    assert!(Number::parse_float("invalid float").value_of().is_nan());
+    assert_eq!(Number::parse_float("123456.789"), 123456.789);
+    assert!(Number::parse_float("invalid float").is_nan());
 }
 
 #[wasm_bindgen_test]
 fn to_locale_string() {
-    let number = Number::new(1234.45.into());
+    let number = Number::new(&1234.45.into());
     assert_eq!(number.to_locale_string("en-US"), "1,234.45");
     // TODO: these tests seems to be system dependent, disable for now
     // assert_eq!(wasm.to_locale_string(number, "de-DE"), "1,234.45");
@@ -77,30 +77,30 @@ fn to_locale_string() {
 
 #[wasm_bindgen_test]
 fn to_precision() {
-    assert_eq!(Number::new(0.1.into()).to_precision(3).unwrap(), "0.100");
-    assert!(Number::new(10.into()).to_precision(101).is_err());
+    assert_eq!(Number::new(&0.1.into()).to_precision(3).unwrap(), "0.100");
+    assert!(Number::new(&10.into()).to_precision(101).is_err());
 }
 
 #[wasm_bindgen_test]
 fn to_string() {
-    assert_eq!(Number::new(42.into()).to_string(10).unwrap(), "42");
-    assert_eq!(Number::new(233.into()).to_string(16).unwrap(), "e9");
-    assert!(Number::new(100.into()).to_string(100).is_err());
+    assert_eq!(Number::new(&42.into()).to_string(10).unwrap(), "42");
+    assert_eq!(Number::new(&233.into()).to_string(16).unwrap(), "e9");
+    assert!(Number::new(&100.into()).to_string(100).is_err());
 }
 
 #[wasm_bindgen_test]
 fn value_of() {
-    assert_eq!(Number::new(42.into()).value_of(), 42.);
+    assert_eq!(Number::new(&42.into()).value_of(), 42.);
 }
 
 #[wasm_bindgen_test]
 fn to_fixed() {
-    assert_eq!(Number::new(123.456.into()).to_fixed(2).unwrap(), "123.46");
-    assert!(Number::new(10.into()).to_fixed(101).is_err());
+    assert_eq!(Number::new(&123.456.into()).to_fixed(2).unwrap(), "123.46");
+    assert!(Number::new(&10.into()).to_fixed(101).is_err());
 }
 
 #[wasm_bindgen_test]
 fn to_exponential() {
-    assert_eq!(Number::new(123456.into()).to_exponential(2).unwrap(), "1.23e+5");
-    assert!(Number::new(10.into()).to_exponential(101).is_err());
+    assert_eq!(Number::new(&123456.into()).to_exponential(2).unwrap(), "1.23e+5");
+    assert!(Number::new(&10.into()).to_exponential(101).is_err());
 }
diff --git a/crates/js-sys/tests/wasm/Reflect.rs b/crates/js-sys/tests/wasm/Reflect.rs
index 2d32cca7..a7c42748 100644
--- a/crates/js-sys/tests/wasm/Reflect.rs
+++ b/crates/js-sys/tests/wasm/Reflect.rs
@@ -42,15 +42,15 @@ extern {
 #[wasm_bindgen_test]
 fn apply() {
     let args = Array::new();
-    args.push(3.into());
+    args.push(&3.into());
     assert_eq!(Reflect::apply(&get_char_at(), &"ponies".into(), &args).unwrap(), "i");
 }
 
 #[wasm_bindgen_test]
 fn construct() {
     let args = Array::new();
-    args.push(10.into());
-    args.push(10.into());
+    args.push(&10.into());
+    args.push(&10.into());
     let instance = Reflect::construct(&RECTANGLE_CLASS, &args);
     assert_eq!(Rectangle::from(instance).x(), 10);
 }
@@ -58,8 +58,8 @@ fn construct() {
 #[wasm_bindgen_test]
 fn construct_with_new_target() {
     let args = Array::new();
-    args.push(10.into());
-    args.push(10.into());
+    args.push(&10.into());
+    args.push(&10.into());
     let instance = Reflect::construct_with_new_target(
         &RECTANGLE_CLASS,
         &args,
@@ -86,10 +86,10 @@ fn delete_property() {
     assert!(r.x_jsval().is_undefined());
 
     let array = Array::new();
-    array.push(1.into());
+    array.push(&1.into());
     let obj = Object::from(JsValue::from(array));
     Reflect::delete_property(&obj, &0.into());
-    let array = Array::from(JsValue::from(obj));
+    let array = Array::from(&JsValue::from(obj));
     assert!(array.length() == 1);
     array.for_each(&mut |x, _, _| assert!(x.is_undefined()));
 }
diff --git a/crates/js-sys/tests/wasm/SetIterator.rs b/crates/js-sys/tests/wasm/SetIterator.rs
index c3d3e355..5df4b254 100644
--- a/crates/js-sys/tests/wasm/SetIterator.rs
+++ b/crates/js-sys/tests/wasm/SetIterator.rs
@@ -22,7 +22,7 @@ fn entries() {
     let iter = GenericIterator::from(JsValue::from(s.entries()));
     let obj = iter.next();
     assert!(!obj.done());
-    let array = Array::from(obj.value());
+    let array = Array::from(&obj.value());
     assert_eq!(array.length(), 2);
     array.for_each(&mut |a, _, _| {
         assert_eq!(a, 1);
diff --git a/crates/js-sys/tests/wasm/TypedArray.rs b/crates/js-sys/tests/wasm/TypedArray.rs
index 53b01c76..e3b6292a 100644
--- a/crates/js-sys/tests/wasm/TypedArray.rs
+++ b/crates/js-sys/tests/wasm/TypedArray.rs
@@ -18,7 +18,7 @@ macro_rules! each {
 
 macro_rules! test_undefined {
     ($arr:ident) => ({
-        let arr = $arr::new(JsValue::undefined());
+        let arr = $arr::new(&JsValue::undefined());
         assert_eq!(arr.length(), 0);
         assert_eq!(arr.byte_length(), 0);
         assert_eq!(arr.byte_offset(), 0);
@@ -32,7 +32,7 @@ fn new_undefined() {
 
 macro_rules! test_length {
     ($arr:ident) => ({
-        let arr = $arr::new(4.into());
+        let arr = $arr::new(&4.into());
         assert_eq!(arr.length(), 4);
         assert!(arr.byte_length() != 0);
         assert_eq!(arr.byte_offset(), 0);
@@ -46,7 +46,7 @@ fn new_length() {
 
 macro_rules! test_subarray {
     ($arr:ident) => ({
-        assert_eq!($arr::new(4.into()).subarray(0, 1).length(), 1);
+        assert_eq!($arr::new(&4.into()).subarray(0, 1).length(), 1);
     })
 }
 #[wasm_bindgen_test]
@@ -56,7 +56,7 @@ fn new_subarray() {
 
 macro_rules! test_fill {
     ($arr:ident) => ({
-        let arr = $arr::new(4.into());
+        let arr = $arr::new(&4.into());
         arr.for_each(&mut |x, _, _| {
             assert_eq!(x as f64, 0.0);
         });
diff --git a/crates/js-sys/tests/wasm/WeakMap.rs b/crates/js-sys/tests/wasm/WeakMap.rs
index 26d76f12..b6c4c405 100644
--- a/crates/js-sys/tests/wasm/WeakMap.rs
+++ b/crates/js-sys/tests/wasm/WeakMap.rs
@@ -24,7 +24,7 @@ fn new() {
 fn get_and_set() {
     let map = WeakMap::new();
     let key = some_key();
-    map.set(&key, "value".into());
+    map.set(&key, &"value".into());
     assert_eq!(map.get(&key), "value");
     assert_eq!(map.get(&Object::new()), JsValue::undefined());
     assert_eq!(map.get(&some_key()), JsValue::undefined());
@@ -34,7 +34,7 @@ fn get_and_set() {
 fn has() {
     let map = WeakMap::new();
     let key = some_key();
-    map.set(&key, "value".into());
+    map.set(&key, &"value".into());
     assert!(map.has(&key));
     assert!(!map.has(&Object::new()));
     assert!(!map.has(&some_key()));
@@ -45,7 +45,7 @@ fn delete() {
     let map = WeakMap::new();
     let key = some_key();
     assert!(!map.has(&key));
-    map.set(&key, "value".into());
+    map.set(&key, &"value".into());
     assert!(map.has(&key));
     map.delete(&key);
     assert!(!map.has(&key));
diff --git a/crates/js-sys/tests/wasm/WebAssembly.rs b/crates/js-sys/tests/wasm/WebAssembly.rs
index f7d71e79..14fc5307 100644
--- a/crates/js-sys/tests/wasm/WebAssembly.rs
+++ b/crates/js-sys/tests/wasm/WebAssembly.rs
@@ -3,7 +3,7 @@ use js_sys::*;
 
 #[wasm_bindgen_test]
 fn validate() {
-    assert!(!WebAssembly::validate(ArrayBuffer::new(42).into()).unwrap());
+    assert!(!WebAssembly::validate(&ArrayBuffer::new(42).into()).unwrap());
 
-    assert!(WebAssembly::validate(2.into()).is_err());
+    assert!(WebAssembly::validate(&2.into()).is_err());
 }
diff --git a/crates/js-sys/tests/wasm/main.rs b/crates/js-sys/tests/wasm/main.rs
old mode 100644
new mode 100755
diff --git a/crates/test/src/rt.rs b/crates/test/src/rt.rs
index de863a96..746aa815 100644
--- a/crates/test/src/rt.rs
+++ b/crates/test/src/rt.rs
@@ -92,7 +92,7 @@ impl Context {
     pub fn run(&self, tests: Vec<JsValue>) -> bool {
         let this = JsValue::null();
         let args = Array::new();
-        args.push(JsValue::from(self as *const Context as u32));
+        args.push(&JsValue::from(self as *const Context as u32));
 
         let noun = if tests.len() == 1 { "test" } else { "tests" };
         console_log!("running {} {}", tests.len(), noun);
diff --git a/examples/closures/src/lib.rs b/examples/closures/src/lib.rs
old mode 100644
new mode 100755
index 27ea2c24..02e98ab2
--- a/examples/closures/src/lib.rs
+++ b/examples/closures/src/lib.rs
@@ -4,7 +4,6 @@ extern crate wasm_bindgen;
 extern crate js_sys;
 
 use js_sys::Date;
-use js_sys::JsString;
 use wasm_bindgen::prelude::*;
 
 #[wasm_bindgen]
@@ -55,8 +54,8 @@ pub fn run() {
         document
             .get_element_by_id("current-time")
             .set_inner_html(&String::from(
-                Date::new(JsValue::undefined())
-                    .to_locale_string("en-GB".into(), JsValue::undefined()),
+                Date::new(&JsValue::undefined())
+                    .to_locale_string(&"en-GB".into(), &JsValue::undefined()),
             ));
     }