////  BaseScriptEngine.cpp//  libraries/script-engine/src////  Created by Timothy Dedischew on 02/01/17.//  Copyright 2017 High Fidelity, Inc.////  Distributed under the Apache License, Version 2.0.//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html// #include "BaseScriptEngine.h" #include <QtCore/QString>#include <QtCore/QThread>#include <QtCore/QUrl>#include <QtScript/QScriptValue>#include <QtScript/QScriptValueIterator>#include <QtScript/QScriptContextInfo> #include "ScriptEngineLogging.h"#include "Profile.h" const QString BaseScriptEngine::_SETTINGS_ENABLE_EXTENDED_EXCEPTIONS {    "com.highfidelity.experimental.enableExtendedJSExceptions"}; const QString BaseScriptEngine::SCRIPT_EXCEPTION_FORMAT { "[%0] %1 in %2:%3" };const QString BaseScriptEngine::SCRIPT_BACKTRACE_SEP { "\n    " }; // engine-aware JS Error copier and factoryQScriptValue BaseScriptEngine::makeError(const QScriptValue& _other, const QString& type) {    auto other = _other;    if (other.isString()) {        other = newObject();        other.setProperty("message", _other.toString());    }    auto proto = globalObject().property(type);    if (!proto.isFunction()) {        proto = globalObject().property(other.prototype().property("constructor").property("name").toString());    }    if (!proto.isFunction()) {#ifdef DEBUG_JS_EXCEPTIONS        qCDebug(scriptengine) << "BaseScriptEngine::makeError -- couldn't find constructor for" << type << " -- using Error instead";#endif        proto = globalObject().property("Error");    }    if (other.engine() != this) {        // JS Objects are parented to a specific script engine instance        // -- this effectively ~clones it locally by routing through a QVariant and back        other = toScriptValue(other.toVariant());    }    // ~ var err = new Error(other.message)    auto err = proto.construct(QScriptValueList({other.property("message")}));     // transfer over any existing properties    QScriptValueIterator it(other);    while (it.hasNext()) {        it.next();        err.setProperty(it.name(), it.value());    }    return err;} // check syntax and when there are issues returns an actual "SyntaxError" with the detailsQScriptValue BaseScriptEngine::lintScript(const QString& sourceCode, const QString& fileName, const int lineNumber) {    const auto syntaxCheck = checkSyntax(sourceCode);    if (syntaxCheck.state() != QScriptSyntaxCheckResult::Valid) {        auto err = globalObject().property("SyntaxError")            .construct(QScriptValueList({syntaxCheck.errorMessage()}));        err.setProperty("fileName", fileName);        err.setProperty("lineNumber", syntaxCheck.errorLineNumber());        err.setProperty("expressionBeginOffset", syntaxCheck.errorColumnNumber());        err.setProperty("stack", currentContext()->backtrace().join(SCRIPT_BACKTRACE_SEP));        {            const auto error = syntaxCheck.errorMessage();            const auto line = QString::number(syntaxCheck.errorLineNumber());            const auto column = QString::number(syntaxCheck.errorColumnNumber());            // for compatibility with legacy reporting            const auto message = QString("[SyntaxError] %1 in %2:%3(%4)").arg(error, fileName, line, column);            err.setProperty("formatted", message);        }        return err;    }    return undefinedValue();} // this pulls from the best available information to create a detailed snapshot of the current exceptionQScriptValue BaseScriptEngine::cloneUncaughtException(const QString& extraDetail) {    if (!hasUncaughtException()) {        return QScriptValue();    }    auto exception = uncaughtException();    // ensure the error object is engine-local    auto err = makeError(exception);     // not sure why Qt does't offer uncaughtExceptionFileName -- but the line number    // on its own is often useless/wrong if arbitrarily married to a filename.    // when the error object already has this info, it seems to be the most reliable    auto fileName = exception.property("fileName").toString();    auto lineNumber = exception.property("lineNumber").toInt32();     // the backtrace, on the other hand, seems most reliable taken from uncaughtExceptionBacktrace    auto backtrace = uncaughtExceptionBacktrace();    if (backtrace.isEmpty()) {        // fallback to the error object        backtrace = exception.property("stack").toString().split(SCRIPT_BACKTRACE_SEP);    }    // the ad hoc "detail" property can be used now to embed additional clues    auto detail = exception.property("detail").toString();    if (detail.isEmpty()) {        detail = extraDetail;    } else if (!extraDetail.isEmpty()) {        detail += "(" + extraDetail + ")";    }    if (lineNumber <= 0) {        lineNumber = uncaughtExceptionLineNumber();    }    if (fileName.isEmpty()) {        // climb the stack frames looking for something useful to display        for(auto ctx = currentContext(); ctx && fileName.isEmpty(); ctx = ctx->parentContext()) {            QScriptContextInfo info { ctx };            if (!info.fileName().isEmpty()) {                // take fileName:lineNumber as a pair                fileName = info.fileName();                lineNumber = info.lineNumber();                if (backtrace.isEmpty()) {                    backtrace = ctx->backtrace();                }                break;            }        }    }    err.setProperty("fileName", fileName);    err.setProperty("lineNumber", lineNumber );    err.setProperty("detail", detail);    err.setProperty("stack", backtrace.join(SCRIPT_BACKTRACE_SEP)); #ifdef DEBUG_JS_EXCEPTIONS    err.setProperty("_fileName", exception.property("fileName").toString());    err.setProperty("_stack", uncaughtExceptionBacktrace().join(SCRIPT_BACKTRACE_SEP));    err.setProperty("_lineNumber", uncaughtExceptionLineNumber());#endif    return err;} QString BaseScriptEngine::formatException(const QScriptValue& exception) {    QString note { "UncaughtException" };    QString result;     if (!exception.isObject()) {        return result;    }    const auto message = exception.toString();    const auto fileName = exception.property("fileName").toString();    const auto lineNumber = exception.property("lineNumber").toString();    const auto stacktrace =  exception.property("stack").toString();     if (_enableExtendedJSExceptions.get()) {        // This setting toggles display of the hints now being added during the loading process.        // Example difference:        //   [UncaughtExceptions] Error: Can't find variable: foobar in atp:/myentity.js\n...        //   [UncaughtException (construct {1eb5d3fa-23b1-411c-af83-163af7220e3f})] Error: Can't find variable: foobar in atp:/myentity.js\n...        if (exception.property("detail").isValid()) {            note += " " + exception.property("detail").toString();        }    }     result = QString(SCRIPT_EXCEPTION_FORMAT).arg(note, message, fileName, lineNumber);    if (!stacktrace.isEmpty()) {        result += QString("\n[Backtrace]%1%2").arg(SCRIPT_BACKTRACE_SEP).arg(stacktrace);    }    return result;} QScriptValue BaseScriptEngine::evaluateInClosure(const QScriptValue& closure, const QScriptProgram& program) {    PROFILE_RANGE(script, "evaluateInClosure");    if (QThread::currentThread() != thread()) {        qCCritical(scriptengine) << "*** CRITICAL *** ScriptEngine::evaluateInClosure() is meant to be called from engine thread only.";        // note: a recursive mutex might be needed around below code if this method ever becomes Q_INVOKABLE        return QScriptValue();    }     //_debugDump("evaluateInClosure.closure", closure);     const auto fileName = program.fileName();    const auto shortName = QUrl(fileName).fileName();     QScriptValue result;    QScriptValue oldGlobal;    auto global = closure.property("global");    if (global.isObject()) {#ifdef DEBUG_JS        qCDebug(scriptengine) << " setting global = closure.global" << shortName;#endif        oldGlobal = globalObject();        setGlobalObject(global);    }     auto ctx = pushContext();     auto thiz = closure.property("this");    if (thiz.isObject()) {#ifdef DEBUG_JS        qCDebug(scriptengine) << " setting this = closure.this" << shortName;#endif        ctx->setThisObject(thiz);    }     ctx->pushScope(closure);#ifdef DEBUG_JS    qCDebug(scriptengine) << QString("[%1] evaluateInClosure %2").arg(isEvaluating()).arg(shortName);#endif    {        ExceptionEmitter tryCatch(this, __FUNCTION__);        result = BaseScriptEngine::evaluate(program);        if (tryCatch.hasPending()) {            auto err = tryCatch.pending();#ifdef DEBUG_JS_EXCEPTIONS            qCWarning(scriptengine) << __FUNCTION__ << "---------- hasCaught:" << err.toString() << result.toString();            err.setProperty("_result", result);#endif            result = err;        }    }#ifdef DEBUG_JS    qCDebug(scriptengine) << QString("[%1] //evaluateInClosure %2").arg(isEvaluating()).arg(shortName);#endif    popContext();     if (oldGlobal.isValid()) {#ifdef DEBUG_JS        qCDebug(scriptengine) << " restoring global" << shortName;#endif        setGlobalObject(oldGlobal);    }     return result;} // Lambda QScriptValue BaseScriptEngine::newLambdaFunction(std::function<QScriptValue(QScriptContext *, QScriptEngine*)> operation, const QScriptValue& data, const QScriptEngine::ValueOwnership& ownership) {    auto lambda = new Lambda(this, operation, data);    auto object = newQObject(lambda, ownership);    auto call = object.property("call");    call.setPrototype(object); // ctx->callee().prototype() === Lambda QObject    call.setData(data);        // ctx->callee().data() will === data param    return call;}QString Lambda::toString() const {    return QString("[Lambda%1]").arg(data.isValid() ? " " + data.toString() : data.toString());} Lambda::~Lambda() {#ifdef DEBUG_JS_LAMBDA_FUNCS    qDebug() << "~Lambda" << "this" << this;#endif} Lambda::Lambda(QScriptEngine *engine, std::function<QScriptValue(QScriptContext *, QScriptEngine*)> operation, QScriptValue data)    : engine(engine), operation(operation), data(data) {#ifdef DEBUG_JS_LAMBDA_FUNCS    qDebug() << "Lambda" << data.toString();#endif}QScriptValue Lambda::call() {    return operation(engine->currentContext(), engine);} // BaseScriptEngine::ExceptionEmitter void BaseScriptEngine::_emitUnhandledException(const QScriptValue& exception) {    emit unhandledException(exception);}BaseScriptEngine::ExceptionEmitter::ExceptionEmitter(BaseScriptEngine* engine, const QString& debugName)    : _engine(engine), _debugName(debugName) {}bool BaseScriptEngine::ExceptionEmitter::hasPending() {    return _engine->hasUncaughtException();}QScriptValue BaseScriptEngine::ExceptionEmitter::pending() {    return _engine->cloneUncaughtException(_debugName);}QScriptValue BaseScriptEngine::ExceptionEmitter::consume() {    if (hasPending()) {        _consumedException = pending();        _engine->clearExceptions();    }    return _consumedException;}bool BaseScriptEngine::ExceptionEmitter::wouldEmit() {    return !_engine->isEvaluating() && _engine->hasUncaughtException();}BaseScriptEngine::ExceptionEmitter::~ExceptionEmitter() {    if (wouldEmit()) {        _engine->_emitUnhandledException(consume());    }}  #ifdef DEBUG_JSvoid BaseScriptEngine::_debugDump(const QString& header, const QScriptValue& object, const QString& footer) {    if (!header.isEmpty()) {        qCDebug(scriptengine) << header;    }    if (!object.isObject()) {        qCDebug(scriptengine) << "(!isObject)" << object.toVariant().toString() << object.toString();        return;    }    QScriptValueIterator it(object);    while (it.hasNext()) {        it.next();        qCDebug(scriptengine) << it.name() << ":" << it.value().toString();    }    if (!footer.isEmpty()) {        qCDebug(scriptengine) << footer;    }}#endif