airbug/bugcore

/*
 * Copyright (c) 2016 airbug Inc. http://airbug.com
 *
 * bugcore may be freely distributed under the MIT license.
 */


//-------------------------------------------------------------------------------
// Annotations
//-------------------------------------------------------------------------------

//@Export('StackTraceUtil')

//@Require('Class')
//@Require('Obj')
//@Require('StringUtil')


//-------------------------------------------------------------------------------
// Context
//-------------------------------------------------------------------------------

require('bugpack').context("*", function(bugpack) {

    //-------------------------------------------------------------------------------
    // BugPack
    //-------------------------------------------------------------------------------

    var Class       = bugpack.require('Class');
    var Obj         = bugpack.require('Obj');
    var StringUtil  = bugpack.require('StringUtil');


    //-------------------------------------------------------------------------------
    // Declare Class
    //-------------------------------------------------------------------------------

    /**
     * @class
     * @extends {Obj}
     */
    var StackTraceUtil = Class.extend(Obj, {
        _name: "StackTraceUtil"
    });


    //-------------------------------------------------------------------------------
    // Static Methods
    //-------------------------------------------------------------------------------

    /**
     * Open source code taken from http://www.eriwen.com/javascript/js-stack-trace/
     * @static
     * @return {string}
     */
    StackTraceUtil.generateStackTrace = function() {
        var callstack = [];
        var isCallstackPopulated = false;

        //NOTE BRN: See more info about this line https://code.google.com/p/v8/wiki/JavaScriptStackTraceApi
        Error.stackTraceLimit = Infinity;

        var error = new Error();
        if (error.stack) { //Firefox & nodejs
            callstack = error.stack.split('\n');
            callstack.shift();
            isCallstackPopulated = true;
        } else if (window.opera && error.message) { //Opera
            var lines = error.message.split('\n');
            for (var i = 0, len = lines.length; i < len; i++) {
                if (lines[i].match(/^\s*[A-Za-z0-9\-_\$]+\(/)) {
                    var entry = lines[i];
                    //Append next line also since it has the file info
                    if (lines[i+1]) {
                        entry += ' at ' + lines[i+1];
                        i++;
                    }
                    callstack.push(entry);
                }
            }
            //Remove call to printStackTrace()
            callstack.shift();
            isCallstackPopulated = true;
        } else {
            var exception = StackTraceUtil.createException();
            if (exception.stack) {
                callstack = exception.stack.split('\n');
                callstack.shift();
                callstack.shift();
                isCallstackPopulated = true;
            }
        }
        if (!isCallstackPopulated) { //IE
            callstack = StackTraceUtil.generateStackFromCaller();
        }
        return callstack.join("\n");
    };


    //-------------------------------------------------------------------------------
    // Static Private Methods
    //-------------------------------------------------------------------------------

    /**
     * @static
     * @private
     * @return {Array.<string>}
     */
    StackTraceUtil.generateStackFromCaller = function() {
        var callstack = [];
        try {
            var currentFunction = arguments.callee.caller;
            while (currentFunction) {
                var fn = currentFunction.toString();
                var fname = fn.substring(0, fn.indexOf("{")) || 'anonymous';
                fname = StringUtil.trim(fname);
                callstack.push(fname);
                currentFunction = currentFunction.caller;
            }
        } catch(error) {
            //TODO BRN: Verify this error is from strict mode
            console.log("Cannot create stack trace in strict mode");
        }
        return callstack;
    };

    /**
     * @static
     * @private
     * @return {*}
     */
    StackTraceUtil.createException = function() {
        try {
            this.undef();
        } catch (e) {
            return e;
        }
    };


    //-------------------------------------------------------------------------------
    // Exports
    //-------------------------------------------------------------------------------

    bugpack.export('StackTraceUtil', StackTraceUtil);
});