utilities.js

linux下开源浏览器WebKit的源码,市面上的很多商用浏览器都是移植自WebKit

    return this.parentNode;
}

function onlyTextChild(ignoreWhitespace)
{
    if (!this)
        return null;

    var firstChild = ignoreWhitespace ? firstChildSkippingWhitespace.call(this) : this.firstChild;
    if (!firstChild || firstChild.nodeType !== Node.TEXT_NODE)
        return null;

    var sibling = ignoreWhitespace ? nextSiblingSkippingWhitespace.call(firstChild) : firstChild.nextSibling;
    return sibling ? null : firstChild;
}

function nodeTitleInfo(hasChildren, linkify)
{
    var info = {title: "", hasChildren: hasChildren};

    switch (this.nodeType) {
        case Node.DOCUMENT_NODE:
            info.title = "Document";
            break;

        case Node.ELEMENT_NODE:
            info.title = "<span class=\"webkit-html-tag\">&lt;" + this.nodeName.toLowerCase().escapeHTML();

            if (this.hasAttributes()) {
                for (var i = 0; i < this.attributes.length; ++i) {
                    var attr = this.attributes[i];
                    info.title += " <span class=\"webkit-html-attribute\"><span class=\"webkit-html-attribute-name\">" + attr.name.escapeHTML() + "</span>=&#8203;\"";

                    var value = attr.value;
                    if (linkify && (attr.name === "src" || attr.name === "href")) {
                        var value = value.replace(/([\/;:\)\]\}])/g, "$1\u200B");
                        info.title += linkify(attr.value, value, "webkit-html-attribute-value", this.nodeName.toLowerCase() == "a");
                    } else {
                        var value = value.escapeHTML();
                        value = value.replace(/([\/;:\)\]\}])/g, "$1&#8203;");
                        info.title += "<span class=\"webkit-html-attribute-value\">" + value + "</span>";
                    }
                    info.title += "\"</span>";
                }
            }
            info.title += "&gt;</span>&#8203;";

            // If this element only has a single child that is a text node,
            // just show that text and the closing tag inline rather than
            // create a subtree for them

            var textChild = onlyTextChild.call(this, Preferences.ignoreWhitespace);
            var showInlineText = textChild && textChild.textContent.length < Preferences.maxInlineTextChildLength;

            if (showInlineText) {
                info.title += "<span class=\"webkit-html-text-node\">" + textChild.nodeValue.escapeHTML() + "</span>&#8203;<span class=\"webkit-html-tag\">&lt;/" + this.nodeName.toLowerCase().escapeHTML() + "&gt;</span>";
                info.hasChildren = false;
            }
            break;

        case Node.TEXT_NODE:
            if (isNodeWhitespace.call(this))
                info.title = "(whitespace)";
            else
                info.title = "\"<span class=\"webkit-html-text-node\">" + this.nodeValue.escapeHTML() + "</span>\"";
            break

        case Node.COMMENT_NODE:
            info.title = "<span class=\"webkit-html-comment\">&lt;!--" + this.nodeValue.escapeHTML() + "--&gt;</span>";
            break;

        case Node.DOCUMENT_TYPE_NODE:
            info.title = "<span class=\"webkit-html-doctype\">&lt;!DOCTYPE " + this.nodeName;
            if (this.publicId) {
                info.title += " PUBLIC \"" + this.publicId + "\"";
                if (this.systemId)
                    info.title += " \"" + this.systemId + "\"";
            } else if (this.systemId)
                info.title += " SYSTEM \"" + this.systemId + "\"";
            if (this.internalSubset)
                info.title += " [" + this.internalSubset + "]";
            info.title += "&gt;</span>";
            break;
        default:
            info.title = this.nodeName.toLowerCase().collapseWhitespace().escapeHTML();
    }

    return info;
}

function getDocumentForNode(node) {
    return node.nodeType == Node.DOCUMENT_NODE ? node : node.ownerDocument;
}

function parentNodeOrFrameElement(node) {
    var parent = node.parentNode;
    if (parent)
        return parent;

    return getDocumentForNode(node).defaultView.frameElement;
}

function isAncestorIncludingParentFrames(a, b) {
    if (objectsAreSame(a, b))
        return false;
    for (var node = b; node; node = getDocumentForNode(node).defaultView.frameElement)
        if (objectsAreSame(a, node) || isAncestorNode.call(a, node))
            return true;
    return false;
}

Number.secondsToString = function(seconds, formatterFunction, higherResolution)
{
    if (!formatterFunction)
        formatterFunction = String.sprintf;

    var ms = seconds * 1000;
    if (higherResolution && ms < 1000)
        return formatterFunction("%.3fms", ms);
    else if (ms < 1000)
        return formatterFunction("%.0fms", ms);

    if (seconds < 60)
        return formatterFunction("%.2fs", seconds);

    var minutes = seconds / 60;
    if (minutes < 60)
        return formatterFunction("%.1fmin", minutes);

    var hours = minutes / 60;
    if (hours < 24)
        return formatterFunction("%.1fhrs", hours);

    var days = hours / 24;
    return formatterFunction("%.1f days", days);
}

Number.bytesToString = function(bytes, formatterFunction)
{
    if (!formatterFunction)
        formatterFunction = String.sprintf;

    if (bytes < 1024)
        return formatterFunction("%.0fB", bytes);

    var kilobytes = bytes / 1024;
    if (kilobytes < 1024)
        return formatterFunction("%.2fKB", kilobytes);

    var megabytes = kilobytes / 1024;
    return formatterFunction("%.3fMB", megabytes);
}

Number.constrain = function(num, min, max)
{
    if (num < min)
        num = min;
    else if (num > max)
        num = max;
    return num;
}

HTMLTextAreaElement.prototype.moveCursorToEnd = function()
{
    var length = this.value.length;
    this.setSelectionRange(length, length);
}

Array.prototype.remove = function(value, onlyFirst)
{
    if (onlyFirst) {
        var index = this.indexOf(value);
        if (index !== -1)
            this.splice(index, 1);
        return;
    }

    var length = this.length;
    for (var i = 0; i < length; ++i) {
        if (this[i] === value)
            this.splice(i, 1);
    }
}

function insertionIndexForObjectInListSortedByFunction(anObject, aList, aFunction)
{
    // indexOf returns (-lowerBound - 1). Taking (-result - 1) works out to lowerBound.
    return (-indexOfObjectInListSortedByFunction(anObject, aList, aFunction) - 1);
}

function indexOfObjectInListSortedByFunction(anObject, aList, aFunction)
{
    var first = 0;
    var last = aList.length - 1;
    var floor = Math.floor;
    var mid, c;

    while (first <= last) {
        mid = floor((first + last) / 2);
        c = aFunction(anObject, aList[mid]);

        if (c > 0)
            first = mid + 1;
        else if (c < 0)
            last = mid - 1;
        else {
            //we return the first occurance of an item in the list.
            while (mid > 0 && aFunction(anObject, aList[mid - 1]) === 0)
                mid--;
            return mid;
        }
    }

    // By returning 1 less than the negative lower search bound, we can reuse this function
    // for both indexOf and insertionIndexFor, with some simple arithmetic.
    return (-first - 1);
}

String.sprintf = function(format)
{
    return String.vsprintf(format, Array.prototype.slice.call(arguments, 1));
}

String.tokenizeFormatString = function(format)
{
    var tokens = [];
    var substitutionIndex = 0;

    function addStringToken(str)
    {
        tokens.push({ type: "string", value: str });
    }

    function addSpecifierToken(specifier, precision, substitutionIndex)
    {
        tokens.push({ type: "specifier", specifier: specifier, precision: precision, substitutionIndex: substitutionIndex });
    }

    var index = 0;
    for (var precentIndex = format.indexOf("%", index); precentIndex !== -1; precentIndex = format.indexOf("%", index)) {
        addStringToken(format.substring(index, precentIndex));
        index = precentIndex + 1;

        if (format[index] === "%") {
            addStringToken("%");
            ++index;
            continue;
        }

        if (!isNaN(format[index])) {
            // The first character is a number, it might be a substitution index.
            var number = parseInt(format.substring(index));
            while (!isNaN(format[index]))
                ++index;
            // If the number is greater than zero and ends with a "$",
            // then this is a substitution index.
            if (number > 0 && format[index] === "$") {
                substitutionIndex = (number - 1);
                ++index;
            }
        }

        var precision = -1;
        if (format[index] === ".") {
            // This is a precision specifier. If no digit follows the ".",
            // then the precision should be zero.
            ++index;
            precision = parseInt(format.substring(index));
            if (isNaN(precision))
                precision = 0;
            while (!isNaN(format[index]))
                ++index;
        }

        addSpecifierToken(format[index], precision, substitutionIndex);

        ++substitutionIndex;
        ++index;
    }

    addStringToken(format.substring(index));

    return tokens;
}

String.standardFormatters = {
    d: function(substitution)
    {
        substitution = parseInt(substitution);
        return !isNaN(substitution) ? substitution : 0;
    },

    f: function(substitution, token)
    {
        substitution = parseFloat(substitution);
        if (substitution && token.precision > -1)
            substitution = substitution.toFixed(token.precision);
        return !isNaN(substitution) ? substitution : (token.precision > -1 ? Number(0).toFixed(token.precision) : 0);
    },

    s: function(substitution)
    {
        return substitution;
    },
};

String.vsprintf = function(format, substitutions)
{
    return String.format(format, substitutions, String.standardFormatters, "", function(a, b) { return a + b; }).formattedResult;
}

String.format = function(format, substitutions, formatters, initialValue, append)
{
    if (!format || !substitutions || !substitutions.length)
        return { formattedResult: append(initialValue, format), unusedSubstitutions: substitutions };

    function prettyFunctionName()
    {
        return "String.format(\"" + format + "\", \"" + substitutions.join("\", \"") + "\")";
    }

    function warn(msg)
    {
        console.warn(prettyFunctionName() + ": " + msg);
    }

    function error(msg)
    {
        console.error(prettyFunctionName() + ": " + msg);
    }

    var result = initialValue;
    var tokens = String.tokenizeFormatString(format);
    var usedSubstitutionIndexes = {};

    for (var i = 0; i < tokens.length; ++i) {
        var token = tokens[i];

        if (token.type === "string") {
            result = append(result, token.value);
            continue;
        }

        if (token.type !== "specifier") {
            error("Unknown token type \"" + token.type + "\" found.");
            continue;
        }

        if (token.substitutionIndex >= substitutions.length) {
            // If there are not enough substitutions for the current substitutionIndex
            // just output the format specifier literally and move on.
            error("not enough substitution arguments. Had " + substitutions.length + " but needed " + (token.substitutionIndex + 1) + ", so substitution was skipped.");
            result = append(result, "%" + (token.precision > -1 ? token.precision : "") + token.specifier);
            continue;
        }

        usedSubstitutionIndexes[token.substitutionIndex] = true;

        if (!(token.specifier in formatters)) {
            // Encountered an unsupported format character, treat as a string.
            warn("unsupported format character \u201C" + token.specifier + "\u201D. Treating as a string.");
            result = append(result, substitutions[token.substitutionIndex]);
            continue;
        }

        result = append(result, formatters[token.specifier](substitutions[token.substitutionIndex], token));
    }

    var unusedSubstitutions = [];
    for (var i = 0; i < substitutions.length; ++i) {
        if (i in usedSubstitutionIndexes)
            continue;
        unusedSubstitutions.push(substitutions[i]);
    }

    return { formattedResult: result, unusedSubstitutions: unusedSubstitutions };
}