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@azenla
Last active August 29, 2015 14:21
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// Copyright (c) 2015, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
// Javascript preamble, that lets the output of dart2js run on V8's d8 shell.
// Node wraps files and provides them with a different `this`. The global
// `this` can be accessed through `global`.
var self = this;
if (typeof global != "undefined") self = global; // Node.js.
(function(self) {
// Using strict mode to avoid accidentally defining global variables.
"use strict"; // Should be first statement of this function.
// Location (Uri.base)
var workingDirectory;
// TODO(sgjesse): This does not work on Windows.
if (typeof os == "object" && "system" in os) {
// V8.
workingDirectory = os.system("pwd");
var length = workingDirectory.length;
if (workingDirectory[length - 1] == '\n') {
workingDirectory = workingDirectory.substring(0, length - 1);
}
} else if (typeof process != "undefined" &&
typeof process.cwd == "function") {
// Node.js.
workingDirectory = process.cwd();
}
self.location = { href: "file://" + workingDirectory + "/" };
// Event loop.
// Task queue as cyclic list queue.
var taskQueue = new Array(8); // Length is power of 2.
var head = 0;
var tail = 0;
var mask = taskQueue.length - 1;
function addTask(elem) {
taskQueue[head] = elem;
head = (head + 1) & mask;
if (head == tail) _growTaskQueue();
}
function removeTask() {
if (head == tail) return;
var result = taskQueue[tail];
taskQueue[tail] = undefined;
tail = (tail + 1) & mask;
return result;
}
function _growTaskQueue() {
// head == tail.
var length = taskQueue.length;
var split = head;
taskQueue.length = length * 2;
if (split * 2 < length) { // split < length / 2
for (var i = 0; i < split; i++) {
taskQueue[length + i] = taskQueue[i];
taskQueue[i] = undefined;
}
head += length;
} else {
for (var i = split; i < length; i++) {
taskQueue[length + i] = taskQueue[i];
taskQueue[i] = undefined;
}
tail += length;
}
mask = taskQueue.length - 1;
}
// Mapping from timer id to timer function.
// The timer id is written on the function as .$timerId.
// That field is cleared when the timer is cancelled, but it is not returned
// from the queue until its time comes.
var timerIds = {};
var timerIdCounter = 1; // Counter used to assing ids.
// Zero-timer queue as simple array queue using push/shift.
var zeroTimerQueue = [];
function addTimer(f, ms) {
var id = timerIdCounter++;
f.$timerId = id;
timerIds[id] = f;
if (ms == 0) {
zeroTimerQueue.push(f);
} else {
addDelayedTimer(f, ms);
}
return id;
}
function nextZeroTimer() {
while (zeroTimerQueue.length > 0) {
var action = zeroTimerQueue.shift();
if (action.$timerId !== undefined) return action;
}
}
function nextEvent() {
var action = removeTask();
if (action) {
return action;
}
do {
action = nextZeroTimer();
if (action) break;
var nextList = nextDelayedTimerQueue();
if (!nextList) {
return;
}
var newTime = nextList.shift();
advanceTimeTo(newTime);
zeroTimerQueue = nextList;
} while (true)
var id = action.$timerId;
clearTimerId(action, id);
return action;
}
// Mocking time.
var timeOffset = 0;
var now = function() {
// Install the mock Date object only once.
// Following calls to "now" will just use the new (mocked) Date.now
// method directly.
installMockDate();
now = Date.now;
return Date.now();
};
var originalDate = Date;
var originalNow = originalDate.now;
function advanceTimeTo(time) {
timeOffset = time - originalNow();
}
function installMockDate() {
var NewDate = function Date(Y, M, D, h, m, s, ms) {
if (this instanceof Date) {
// Assume a construct call.
switch (arguments.length) {
case 0: return new originalDate(originalNow() + timeOffset);
case 1: return new originalDate(Y);
case 2: return new originalDate(Y, M);
case 3: return new originalDate(Y, M, D);
case 4: return new originalDate(Y, M, D, h);
case 5: return new originalDate(Y, M, D, h, m);
case 6: return new originalDate(Y, M, D, h, m, s);
default: return new originalDate(Y, M, D, h, m, s, ms);
}
}
return new originalDate(originalNow() + timeOffset).toString();
};
NewDate.UTC = originalDate.UTC;
NewDate.parse = originalDate.parse;
NewDate.now = function now() { return originalNow() + timeOffset; };
NewDate.prototype = originalDate.prototype;
originalDate.prototype.constructor = NewDate;
Date = NewDate;
}
// Heap priority queue with key index.
// Each entry is list of [timeout, callback1 ... callbackn].
var timerHeap = [];
var timerIndex = {};
function addDelayedTimer(f, ms) {
var timeout = now() + ms;
var timerList = timerIndex[timeout];
if (timerList == null) {
timerList = [timeout, f];
timerIndex[timeout] = timerList;
var index = timerHeap.length;
timerHeap.length += 1;
bubbleUp(index, timeout, timerList);
} else {
timerList.push(f);
}
}
function nextDelayedTimerQueue() {
if (timerHeap.length == 0) return null;
var result = timerHeap[0];
var last = timerHeap.pop();
if (timerHeap.length > 0) {
bubbleDown(0, last[0], last);
}
return result;
}
function bubbleUp(index, key, value) {
while (index != 0) {
var parentIndex = (index - 1) >> 1;
var parent = timerHeap[parentIndex];
var parentKey = parent[0];
if (key > parentKey) break;
timerHeap[index] = parent;
index = parentIndex;
}
timerHeap[index] = value;
}
function bubbleDown(index, key, value) {
while (true) {
var leftChildIndex = index * 2 + 1;
if (leftChildIndex >= timerHeap.length) break;
var minChildIndex = leftChildIndex;
var minChild = timerHeap[leftChildIndex];
var minChildKey = minChild[0];
var rightChildIndex = leftChildIndex + 1;
if (rightChildIndex < timerHeap.length) {
var rightChild = timerHeap[rightChildIndex];
var rightKey = rightChild[0];
if (rightKey < minChildKey) {
minChildIndex = rightChildIndex;
minChild = rightChild;
minChildKey = rightKey;
}
}
if (minChildKey > key) break;
timerHeap[index] = minChild;
index = minChildIndex;
}
timerHeap[index] = value;
}
function addInterval(f, ms) {
var id = timerIdCounter++;
function repeat() {
// Reactivate with the same id.
repeat.$timerId = id;
timerIds[id] = repeat;
addDelayedTimer(repeat, ms);
f();
}
repeat.$timerId = id;
timerIds[id] = repeat;
addDelayedTimer(repeat, ms);
return id;
}
function cancelTimer(id) {
var f = timerIds[id];
if (f == null) return;
clearTimerId(f, id);
}
function clearTimerId(f, id) {
f.$timerId = undefined;
delete timerIds[id];
}
function eventLoop(action) {
while (action) {
try {
action();
} catch (e) {
if (typeof onerror == "function") {
onerror(e, null, -1);
} else {
throw e;
}
}
action = nextEvent();
}
}
// Global properties. "self" refers to the global object, so adding a
// property to "self" defines a global variable.
self.self = self
self.dartMainRunner = function(main, args) {
// Initialize.
var action = function() { main(args); }
eventLoop(action);
};
self.setTimeout = addTimer;
self.clearTimeout = cancelTimer;
self.setInterval = addInterval;
self.clearInterval = cancelTimer;
self.scheduleImmediate = addTask;
self.require = require;
self.global = global;
// Support for deferred loading.
self.dartDeferredLibraryLoader = function(uri, successCallback, errorCallback) {
try {
load(uri);
successCallback();
} catch (error) {
errorCallback(error);
}
};
})(self);
require('vm').runInThisContext(require('fs').readFileSync(require('path').normalize(process.argv[2])).toString());
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