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// See "Wasm Function.prototype.call.bind optimization" in WasmInstance.cpp
// for more information.
function wrapFunc(params, func) {
let funcCallBind = Function.prototype.call.bind(func);
return wasmEvalText(`(module
(func (import "" "f") (param ${params.join(" ")}))
(func (export "f") (param ${params.join(" ")})
${params.map((x, i) => `local.get ${i}`).join("\n")}
call 0
)
)`, {"": {"f": funcCallBind}}).exports.f;
}
// Test passing all kinds of externref values to func through the 'this'
// parameter.
{
let func = function (expected) {
"use strict";
assertEq(this, expected);
};
let test = wrapFunc(["externref", "externref"], func);
for (let val of WasmExternrefValues) {
test(val, val);
}
}
// Same as above but with two non-this params.
{
let func = function (a, b) {
"use strict";
assertEq(this, a);
assertEq(a, b);
};
let test = wrapFunc(["externref", "externref", "externref"], func);
for (let val of WasmExternrefValues) {
test(val, val, val);
}
}
// Test passing primitives as the 'this' value.
{
let func = function (expected) {
"use strict";
assertEq(this, expected);
};
let vals = [0, 1, 2, 3, 4, 5];
for (let valType of ["i32", "i64", "f32", "f64"]) {
let test = wrapFunc([valType, valType], func);
for (let val of vals) {
if (valType === "i64") {
val = BigInt(val);
}
test(val, val);
}
}
}
// Function.prototype.call on a non-strict function will coerce null/undefined
// to the global object.
{
let func = function (expected) {
assertEq(this, expected);
};
let test = wrapFunc(["externref", "externref"], func);
test(null, globalThis);
test(undefined, globalThis);
}
// Test binding extra JS arguments still works (this should skip the
// optimization)
{
function func(x) {
"use strict";
assertEq(this, 1);
assertEq(x, 2);
}
// Bind '2' to be the first normal arg to 'call', which will then become
// the 'this' parameter always.
let funcCallBind = Function.prototype.call.bind(func, 1);
let {test} = wasmEvalText(`(module
(func (import "" "f") (param i32))
(export "test" (func 0))
)`, {"": {"f": funcCallBind}}).exports;
test(2);
}
// Test a missing this parameter.
{
let test = wrapFunc([], function () {
"use strict";
assertEq(this, undefined);
});
test();
}