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// Copyright 2014 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Flags: --allow-natives-syntax
var Debug = debug.Debug;
unique_id = 0;
var Generator = (function*(){}).constructor;
function assertIteratorResult(value, done, result) {
assertEquals({value: value, done: done}, result);
}
function MakeGenerator() {
// Prevents eval script caching.
unique_id++;
return Generator('callback',
"/* " + unique_id + "*/\n" +
"yield callback();\n" +
"return 'Cat';\n");
}
function MakeFunction() {
// Prevents eval script caching.
unique_id++;
return Function('callback',
"/* " + unique_id + "*/\n" +
"callback();\n" +
"return 'Cat';\n");
}
// First, try MakeGenerator with no perturbations.
(function(){
var generator = MakeGenerator();
function callback() {};
var iter = generator(callback);
assertIteratorResult(undefined, false, iter.next());
assertIteratorResult("Cat", true, iter.next());
})();
function ExecuteInDebugContext(f) {
var result;
var exception = null;
Debug.setListener(function(event) {
if (event == Debug.DebugEvent.Break) {
try {
result = f();
} catch (e) {
// Rethrow this exception later.
exception = e;
}
}
});
debugger;
Debug.setListener(null);
if (exception !== null) throw exception;
return result;
}
function patch(fun, from, to) {
function debug() {
%LiveEditPatchScript(fun, Debug.scriptSource(fun).replace(from, to));
}
ExecuteInDebugContext(debug);
}
// Try to edit a MakeGenerator while it's running, then again while it's
// stopped.
(function(){
var generator = MakeGenerator();
var gen_patch_attempted = false;
function attempt_gen_patch() {
assertFalse(gen_patch_attempted);
gen_patch_attempted = true;
assertThrowsEquals(function() {
patch(generator, '\'Cat\'', '\'Capybara\'')
}, 'LiveEdit failed: BLOCKED_BY_FUNCTION_BELOW_NON_DROPPABLE_FRAME');
};
var iter = generator(attempt_gen_patch);
assertIteratorResult(undefined, false, iter.next());
// Patch should not succeed because there is a live generator activation on
// the stack.
assertIteratorResult("Cat", true, iter.next());
assertTrue(gen_patch_attempted);
// At this point one iterator is live, but closed, so the patch will succeed.
patch(generator, "'Cat'", "'Capybara'");
iter = generator(function(){});
assertIteratorResult(undefined, false, iter.next());
// Patch successful.
assertIteratorResult("Capybara", true, iter.next());
// Patching will fail however when a live iterator is suspended.
iter = generator(function(){});
assertIteratorResult(undefined, false, iter.next());
assertThrowsEquals(function() {
patch(generator, '\'Capybara\'', '\'Tapir\'')
}, 'LiveEdit failed: BLOCKED_BY_RUNNING_GENERATOR');
assertIteratorResult("Capybara", true, iter.next());
// Try to patch functions with activations inside and outside generator
// function activations. We should succeed in the former case, but not in the
// latter.
var fun_outside = MakeFunction();
var fun_inside = MakeFunction();
var fun_patch_attempted = false;
var fun_patch_restarted = false;
function attempt_fun_patches() {
if (fun_patch_attempted) {
assertFalse(fun_patch_restarted);
fun_patch_restarted = true;
return;
}
fun_patch_attempted = true;
// Patching outside a generator activation must fail.
assertThrowsEquals(function() {
patch(fun_outside, '\'Cat\'', '\'Cobra\'')
}, 'LiveEdit failed: BLOCKED_BY_FUNCTION_BELOW_NON_DROPPABLE_FRAME');
// Patching inside a generator activation may succeed.
patch(fun_inside, "'Cat'", "'Koala'");
}
iter = generator(function() { return fun_inside(attempt_fun_patches) });
assertEquals('Cat',
fun_outside(function () {
assertIteratorResult('Koala', false, iter.next());
assertTrue(fun_patch_restarted);
}));
})();
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