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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
// Trailing comma in functions and generators.
// 14.1 Function Definitions
// FunctionDeclaration[Yield, Default]:
// function BindingIdentifier[?Yield] ( FormalParameters[~Yield] ) { FunctionBody[~Yield] }
// 14.4 Generator Function Definitions
// GeneratorDeclaration[Yield, Default]:
// function * BindingIdentifier[?Yield] ( FormalParameters[+Yield] ) { GeneratorBody }
function functionDeclaration(argList, parameters = "", returnExpr = "") {
return eval(`
function f(${argList}) {
var fun = f;
return ${returnExpr};
}
f(${parameters});
`);
}
function generatorDeclaration(argList, parameters = "", returnExpr = "") {
return eval(`
function* f(${argList}) {
var fun = f;
return ${returnExpr};
}
f(${parameters}).next().value;
`);
}
const tests = [
functionDeclaration,
generatorDeclaration,
];
// Ensure parameters are passed correctly.
for (let test of tests) {
assertEq(test("a, ", "10", "a"), 10);
assertEq(test("a, b, ", "10, 20", "a + b"), 30);
assertEq(test("a = 30, ", "", "a"), 30);
assertEq(test("a = 30, b = 40, ", "", "a + b"), 70);
assertEq(test("[a], ", "[10]", "a"), 10);
assertEq(test("[a], [b], ", "[10], [20]", "a + b"), 30);
assertEq(test("[a] = [30], ", "", "a"), 30);
assertEq(test("[a] = [30], [b] = [40], ", "", "a + b"), 70);
assertEq(test("{a}, ", "{a: 10}", "a"), 10);
assertEq(test("{a}, {b}, ", "{a: 10}, {b: 20}", "a + b"), 30);
assertEq(test("{a} = {a: 30}, ", "", "a"), 30);
assertEq(test("{a} = {a: 30}, {b} = {b: 40}, ", "", "a + b"), 70);
}
// Ensure function length doesn't change.
for (let test of tests) {
assertEq(test("a, ", "", "fun.length"), 1);
assertEq(test("a, b, ", "", "fun.length"), 2);
assertEq(test("[a], ", "[]", "fun.length"), 1);
assertEq(test("[a], [b], ", "[], []", "fun.length"), 2);
assertEq(test("{a}, ", "{}", "fun.length"), 1);
assertEq(test("{a}, {b}, ", "{}, {}", "fun.length"), 2);
}
for (let test of tests) {
// Trailing comma in empty parameters list.
assertThrowsInstanceOf(() => test(","), SyntaxError);
// Leading comma.
assertThrowsInstanceOf(() => test(", a"), SyntaxError);
assertThrowsInstanceOf(() => test(", ...a"), SyntaxError);
// Multiple trailing comma.
assertThrowsInstanceOf(() => test("a, , "), SyntaxError);
assertThrowsInstanceOf(() => test("a..., , "), SyntaxError);
// Trailing comma after rest parameter.
assertThrowsInstanceOf(() => test("...a, "), SyntaxError);
assertThrowsInstanceOf(() => test("a, ...b, "), SyntaxError);
// Elision.
assertThrowsInstanceOf(() => test("a, , b"), SyntaxError);
}
if (typeof reportCompare === "function")
reportCompare(0, 0);