diff --git a/crates/js-sys/src/lib.rs b/crates/js-sys/src/lib.rs index c11902de..8a78d4c8 100644 --- a/crates/js-sys/src/lib.rs +++ b/crates/js-sys/src/lib.rs @@ -1072,6 +1072,14 @@ extern "C" { arg3: &JsValue, ) -> Result; + /// The bind() method creates a new function that, when called, has its this keyword set to the provided value, + /// with a given sequence of arguments preceding any provided when the new function is called. + /// + /// [MDN documentation](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/bind) + #[wasm_bindgen(method, js_name = bind)] + pub fn bind(this: &Function, context: &JsValue) -> Function; + + /// The bind() method creates a new function that, when called, has its this keyword set to the provided value, /// with a given sequence of arguments preceding any provided when the new function is called. /// diff --git a/crates/js-sys/tests/wasm/Function.js b/crates/js-sys/tests/wasm/Function.js index f445792d..a687622d 100644 --- a/crates/js-sys/tests/wasm/Function.js +++ b/crates/js-sys/tests/wasm/Function.js @@ -5,6 +5,15 @@ exports.get_function_to_bind = function() { exports.get_value_to_bind_to = function() { return { x: 2 }; }; +exports.list = function() { + return Array.prototype.slice.call(arguments); +}; +exports.add_arguments = function() { + return function(arg1, arg2) {return arg1 + arg2} +}; exports.call_function = function(f) { return f(); }; +exports.call_function_arg = function(f, arg1) { + return f(arg1); +}; diff --git a/crates/js-sys/tests/wasm/Function.rs b/crates/js-sys/tests/wasm/Function.rs index 34faf1a9..e83d6318 100644 --- a/crates/js-sys/tests/wasm/Function.rs +++ b/crates/js-sys/tests/wasm/Function.rs @@ -34,17 +34,42 @@ fn apply() { extern "C" { fn get_function_to_bind() -> Function; fn get_value_to_bind_to() -> JsValue; + fn list() -> Function; + fn add_arguments() -> Function; fn call_function(f: Function) -> JsValue; + fn call_function_arg(f: &Function, arg0: JsValue) -> JsValue; + } #[wasm_bindgen_test] fn bind() { + let f = get_function_to_bind(); + let new_f = f.bind(&get_value_to_bind_to()); + assert_eq!(call_function(f), 1); + assert_eq!(call_function(new_f), 2); +} + +#[wasm_bindgen_test] +fn bind0() { let f = get_function_to_bind(); let new_f = f.bind0(&get_value_to_bind_to()); assert_eq!(call_function(f), 1); assert_eq!(call_function(new_f), 2); } +#[wasm_bindgen_test] +fn bind1() { + //let a_list = list(); + //let prepended_list = a_list.bind1(&JsValue::NULL, &JsValue::from(2)); + + let adder = add_arguments(); + let add_42 = adder.bind1(&JsValue::NULL, &JsValue::from(42)); + + assert_eq!(call_function_arg(&add_42, JsValue::from(1)), 43); + assert_eq!(call_function_arg(&add_42, JsValue::from(378)), 420); +} + + #[wasm_bindgen_test] fn length() { assert_eq!(MAX.length(), 2);