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// Tests that the "return" method on iterators is called in yield*
// expressions.
function test() {
var returnCalled = 0;
var returnCalledExpected = 0;
var nextCalled = 0;
var nextCalledExpected = 0;
var throwCalled = 0;
var throwCalledExpected = 0;
var iterable = {};
iterable[Symbol.iterator] = makeIterator({
next: function() {
nextCalled++;
return { done: false };
},
ret: function() {
returnCalled++;
return { done: true, value: "iter.return" };
}
});
function* y() {
yield* iterable;
}
// G.p.throw on an iterator without "throw" calls IteratorClose.
var g1 = y();
g1.next();
assertThrowsInstanceOf(function() {
g1.throw("foo");
}, TypeError);
assertEq(returnCalled, ++returnCalledExpected);
assertEq(nextCalled, ++nextCalledExpected);
g1.next();
assertEq(nextCalled, nextCalledExpected);
// G.p.return calls "return", and if the result.done is true, return the
// result.
var g2 = y();
g2.next();
var v2 = g2.return("test return");
assertEq(v2.done, true);
assertEq(v2.value, "iter.return");
assertEq(returnCalled, ++returnCalledExpected);
assertEq(nextCalled, ++nextCalledExpected);
g2.next();
assertEq(nextCalled, nextCalledExpected);
// G.p.return calls "return", and if the result.done is false, continue
// yielding.
iterable[Symbol.iterator] = makeIterator({
next: function() {
nextCalled++;
return { done: false };
},
ret: function() {
returnCalled++;
return { done: false, value: "iter.return" };
}
});
var g3 = y();
g3.next();
var v3 = g3.return("test return");
assertEq(v3.done, false);
assertEq(v3.value, "iter.return");
assertEq(returnCalled, ++returnCalledExpected);
assertEq(nextCalled, ++nextCalledExpected);
g3.next();
assertEq(nextCalled, ++nextCalledExpected);
// G.p.return throwing does not re-call iter.return.
iterable[Symbol.iterator] = makeIterator({
ret: function() {
returnCalled++;
throw "in iter.return";
}
});
var g4 = y();
g4.next();
assertThrowsValue(function() {
g4.return("in test");
}, "in iter.return");
assertEq(returnCalled, ++returnCalledExpected);
// G.p.return expects iter.return to return an Object.
iterable[Symbol.iterator] = makeIterator({
ret: function() {
returnCalled++;
return 42;
}
});
var g5 = y();
g5.next();
assertThrowsInstanceOf(function() {
g5.return("foo");
}, TypeError);
assertEq(returnCalled, ++returnCalledExpected);
// IteratorClose expects iter.return to return an Object.
var g6 = y();
g6.next();
var exc;
try {
g6.throw("foo");
} catch (e) {
exc = e;
} finally {
assertEq(exc instanceof TypeError, true);
// The message test is here because instanceof TypeError doesn't
// distinguish the non-Object return TypeError and the
// throw-method-is-not-defined iterator protocol error.
assertEq(exc.toString().indexOf("non-object") > 0, true);
}
assertEq(returnCalled, ++returnCalledExpected);
// G.p.return passes its argument to "return".
iterable[Symbol.iterator] = makeIterator({
ret: function(x) {
assertEq(x, "in test");
returnCalled++;
return { done: true };
}
});
var g7 = y();
g7.next();
g7.return("in test");
assertEq(returnCalled, ++returnCalledExpected);
// If a throw method is present, do not call "return".
iterable[Symbol.iterator] = makeIterator({
throw: function(e) {
throwCalled++;
throw e;
},
ret: function(x) {
returnCalled++;
return { done: true };
}
});
var g8 = y();
g8.next();
assertThrowsValue(function() {
g8.throw("foo");
}, "foo");
assertEq(throwCalled, ++throwCalledExpected);
assertEq(returnCalled, returnCalledExpected);
}
test();
if (typeof reportCompare === "function")
reportCompare(0, 0);