1 /*
   2  * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package jdk.nashorn.tools;
  27 
  28 import jdk.nashorn.api.scripting.NashornException;
  29 import jdk.nashorn.internal.codegen.Compiler;
  30 import jdk.nashorn.internal.codegen.Compiler.CompilationPhases;
  31 import jdk.nashorn.internal.ir.Expression;
  32 import jdk.nashorn.internal.ir.FunctionNode;
  33 import jdk.nashorn.internal.ir.debug.ASTWriter;
  34 import jdk.nashorn.internal.ir.debug.PrintVisitor;
  35 import jdk.nashorn.internal.objects.Global;
  36 import jdk.nashorn.internal.objects.NativeSymbol;
  37 import jdk.nashorn.internal.parser.Parser;
  38 import jdk.nashorn.internal.runtime.Context;
  39 import jdk.nashorn.internal.runtime.ErrorManager;
  40 import jdk.nashorn.internal.runtime.JSType;
  41 import jdk.nashorn.internal.runtime.Property;
  42 import jdk.nashorn.internal.runtime.ScriptEnvironment;
  43 import jdk.nashorn.internal.runtime.ScriptFunction;
  44 import jdk.nashorn.internal.runtime.ScriptObject;
  45 import jdk.nashorn.internal.runtime.ScriptRuntime;
  46 import jdk.nashorn.internal.runtime.ScriptingFunctions;
  47 import jdk.nashorn.internal.runtime.Symbol;
  48 import jdk.nashorn.internal.runtime.arrays.ArrayLikeIterator;
  49 import jdk.nashorn.internal.runtime.options.Options;
  50 
  51 import java.io.BufferedReader;
  52 import java.io.File;
  53 import java.io.FileReader;
  54 import java.io.IOException;
  55 import java.io.InputStream;
  56 import java.io.InputStreamReader;
  57 import java.io.OutputStream;
  58 import java.io.PrintStream;
  59 import java.io.PrintWriter;
  60 import java.io.StreamTokenizer;
  61 import java.io.StringReader;
  62 import java.nio.file.Files;
  63 import java.nio.file.Path;
  64 import java.nio.file.Paths;
  65 import java.util.ArrayList;
  66 import java.util.Arrays;
  67 import java.util.Iterator;
  68 import java.util.List;
  69 import java.util.Locale;
  70 import java.util.ResourceBundle;
  71 
  72 import static jdk.nashorn.internal.runtime.Source.sourceFor;
  73 
  74 /**
  75  * Command line Shell for processing JavaScript files.
  76  */
  77 public class Shell implements PartialParser {
  78 
  79     /**
  80      * Resource name for properties file
  81      */
  82     private static final String MESSAGE_RESOURCE = "jdk.nashorn.tools.resources.Shell";
  83     /**
  84      * Shell message bundle.
  85      */
  86     protected static final ResourceBundle bundle = ResourceBundle.getBundle(MESSAGE_RESOURCE, Locale.getDefault());
  87 
  88     /**
  89      * Exit code for command line tool - successful
  90      */
  91     public static final int SUCCESS = 0;
  92     /**
  93      * Exit code for command line tool - error on command line
  94      */
  95     public static final int COMMANDLINE_ERROR = 100;
  96     /**
  97      * Exit code for command line tool - error compiling script
  98      */
  99     public static final int COMPILATION_ERROR = 101;
 100     /**
 101      * Exit code for command line tool - error during runtime
 102      */
 103     public static final int RUNTIME_ERROR = 102;
 104     /**
 105      * Exit code for command line tool - i/o error
 106      */
 107     public static final int IO_ERROR = 103;
 108     /**
 109      * Exit code for command line tool - internal error
 110      */
 111     public static final int INTERNAL_ERROR = 104;
 112 
 113     /**
 114      * Constructor
 115      */
 116     protected Shell() {
 117     }
 118 
 119     /**
 120      * Main entry point with the default input, output and error streams.
 121      *
 122      * @param args The command line arguments
 123      */
 124     public static void main(final String[] args) {
 125         try {
 126             final int exitCode = main(System.in, System.out, System.err, args);
 127             if (exitCode != SUCCESS) {
 128                 System.exit(exitCode);
 129             }
 130         } catch (final IOException e) {
 131             System.err.println(e); //bootstrapping, Context.err may not exist
 132             System.exit(IO_ERROR);
 133         }
 134     }
 135 
 136     /**
 137      * Starting point for executing a {@code Shell}. Starts a shell with the
 138      * given arguments and streams and lets it run until exit.
 139      *
 140      * @param in input stream for Shell
 141      * @param out output stream for Shell
 142      * @param err error stream for Shell
 143      * @param args arguments to Shell
 144      *
 145      * @return exit code
 146      *
 147      * @throws IOException if there's a problem setting up the streams
 148      */
 149     public static int main(final InputStream in, final OutputStream out, final OutputStream err, final String[] args) throws IOException {
 150         return new Shell().run(in, out, err, args);
 151     }
 152 
 153     /**
 154      * Run method logic.
 155      *
 156      * @param in input stream for Shell
 157      * @param out output stream for Shell
 158      * @param err error stream for Shell
 159      * @param args arguments to Shell
 160      *
 161      * @return exit code
 162      *
 163      * @throws IOException if there's a problem setting up the streams
 164      */
 165     protected final int run(final InputStream in, final OutputStream out, final OutputStream err, final String[] args) throws IOException {
 166         final Context context = makeContext(in, out, err, args);
 167         if (context == null) {
 168             return COMMANDLINE_ERROR;
 169         }
 170 
 171         final Global global = context.createGlobal();
 172         final ScriptEnvironment env = context.getEnv();
 173         if (!env._no_deprecation_warning) {
 174             System.err.println("Warning: The jjs tool is planned to be removed from a future JDK release");
 175         }
 176         final List<String> files = env.getFiles();
 177         if (files.isEmpty()) {
 178             return readEvalPrint(context, global);
 179         }
 180 
 181         if (env._compile_only) {
 182             return compileScripts(context, global, files);
 183         }
 184 
 185         if (env._fx) {
 186             return runFXScripts(context, global, files);
 187         }
 188 
 189         return runScripts(context, global, files);
 190     }
 191 
 192     /**
 193      * Make a new Nashorn Context to compile and/or run JavaScript files.
 194      *
 195      * @param in input stream for Shell
 196      * @param out output stream for Shell
 197      * @param err error stream for Shell
 198      * @param args arguments to Shell
 199      *
 200      * @return null if there are problems with option parsing.
 201      */
 202     private static Context makeContext(final InputStream in, final OutputStream out, final OutputStream err, final String[] args) {
 203         final PrintStream pout = out instanceof PrintStream ? (PrintStream) out : new PrintStream(out);
 204         final PrintStream perr = err instanceof PrintStream ? (PrintStream) err : new PrintStream(err);
 205         final PrintWriter wout = new PrintWriter(pout, true);
 206         final PrintWriter werr = new PrintWriter(perr, true);
 207 
 208         // Set up error handler.
 209         final ErrorManager errors = new ErrorManager(werr);
 210         // Set up options.
 211         final Options options = new Options("nashorn", werr);
 212 
 213         // parse options
 214         if (args != null) {
 215             try {
 216                 final String[] prepArgs = preprocessArgs(args);
 217                 options.process(prepArgs);
 218             } catch (final IllegalArgumentException e) {
 219                 werr.println(bundle.getString("shell.usage"));
 220                 options.displayHelp(e);
 221                 return null;
 222             }
 223         }
 224 
 225         // detect scripting mode by any source's first character being '#'
 226         if (!options.getBoolean("scripting")) {
 227             for (final String fileName : options.getFiles()) {
 228                 final File firstFile = new File(fileName);
 229                 if (firstFile.isFile()) {
 230                     try (final FileReader fr = new FileReader(firstFile)) {
 231                         final int firstChar = fr.read();
 232                         // starts with '#
 233                         if (firstChar == '#') {
 234                             options.set("scripting", true);
 235                             break;
 236                         }
 237                     } catch (final IOException e) {
 238                         // ignore this. File IO errors will be reported later anyway
 239                     }
 240                 }
 241             }
 242         }
 243 
 244         return new Context(options, errors, wout, werr, Thread.currentThread().getContextClassLoader());
 245     }
 246 
 247     /**
 248      * Preprocess the command line arguments passed in by the shell. This method checks, for the first non-option
 249      * argument, whether the file denoted by it begins with a shebang line. If so, it is assumed that execution in
 250      * shebang mode is intended. The consequence of this is that the identified script file will be treated as the
 251      * <em>only</em> script file, and all subsequent arguments will be regarded as arguments to the script.
 252      * <p>
 253      * This method canonicalizes the command line arguments to the form {@code <options> <script> -- <arguments>} if a
 254      * shebang script is identified. On platforms that pass shebang arguments as single strings, the shebang arguments
 255      * will be broken down into single arguments; whitespace is used as separator.
 256      * <p>
 257      * Shebang mode is entered regardless of whether the script is actually run directly from the shell, or indirectly
 258      * via the {@code jjs} executable. It is the user's / script author's responsibility to ensure that the arguments
 259      * given on the shebang line do not lead to a malformed argument sequence. In particular, the shebang arguments
 260      * should not contain any whitespace for purposes other than separating arguments, as the different platforms deal
 261      * with whitespace in different and incompatible ways.
 262      * <p>
 263      * @implNote Example:<ul>
 264      * <li>Shebang line in {@code script.js}: {@code #!/path/to/jjs --language=es6}</li>
 265      * <li>Command line: {@code ./script.js arg2}</li>
 266      * <li>{@code args} array passed to Nashorn: {@code --language=es6,./script.js,arg}</li>
 267      * <li>Required canonicalized arguments array: {@code --language=es6,./script.js,--,arg2}</li>
 268      * </ul>
 269      *
 270      * @param args the command line arguments as passed into Nashorn.
 271      * @return the passed and possibly canonicalized argument list
 272      */
 273     private static String[] preprocessArgs(final String[] args) {
 274         if (args.length == 0) {
 275             return args;
 276         }
 277 
 278         final List<String> processedArgs = new ArrayList<>();
 279         processedArgs.addAll(Arrays.asList(args));
 280 
 281         // Nashorn supports passing multiple shebang arguments. On platforms that pass anything following the
 282         // shebang interpreter notice as one argument, the first element of the argument array needs to be special-cased
 283         // as it might actually contain several arguments. Mac OS X splits shebang arguments, other platforms don't.
 284         // This special handling is also only necessary if the first argument actually starts with an option.
 285         if (args[0].startsWith("-") && !System.getProperty("os.name", "generic").startsWith("Mac OS X")) {
 286             processedArgs.addAll(0, tokenizeString(processedArgs.remove(0)));
 287         }
 288 
 289         int shebangFilePos = -1; // -1 signifies "none found"
 290         // identify a shebang file and its position in the arguments array (if any)
 291         for (int i = 0; i < processedArgs.size(); ++i) {
 292             final String a = processedArgs.get(i);
 293             if (!a.startsWith("-")) {
 294                 final Path p = Paths.get(a);
 295                 String l = "";
 296                 try (final BufferedReader r = Files.newBufferedReader(p)) {
 297                     l = r.readLine();
 298                 } catch (final IOException ioe) {
 299                     // ignore
 300                 }
 301                 if (l != null && l.startsWith("#!")) {
 302                     shebangFilePos = i;
 303                 }
 304                 // We're only checking the first non-option argument. If it's not a shebang file, we're in normal
 305                 // execution mode.
 306                 break;
 307             }
 308         }
 309         if (shebangFilePos != -1) {
 310             // Insert the argument separator after the shebang script file.
 311             processedArgs.add(shebangFilePos + 1, "--");
 312         }
 313         return processedArgs.stream().toArray(String[]::new);
 314     }
 315 
 316     public static List<String> tokenizeString(final String str) {
 317         final StreamTokenizer tokenizer = new StreamTokenizer(new StringReader(str));
 318         tokenizer.resetSyntax();
 319         tokenizer.wordChars(0, 255);
 320         tokenizer.whitespaceChars(0, ' ');
 321         tokenizer.commentChar('#');
 322         tokenizer.quoteChar('"');
 323         tokenizer.quoteChar('\'');
 324         final List<String> tokenList = new ArrayList<>();
 325         final StringBuilder toAppend = new StringBuilder();
 326         while (nextToken(tokenizer) != StreamTokenizer.TT_EOF) {
 327             final String s = tokenizer.sval;
 328             // The tokenizer understands about honoring quoted strings and recognizes
 329             // them as one token that possibly contains multiple space-separated words.
 330             // It does not recognize quoted spaces, though, and will split after the
 331             // escaping \ character. This is handled here.
 332             if (s.endsWith("\\")) {
 333                 // omit trailing \, append space instead
 334                 toAppend.append(s.substring(0, s.length() - 1)).append(' ');
 335             } else {
 336                 tokenList.add(toAppend.append(s).toString());
 337                 toAppend.setLength(0);
 338             }
 339         }
 340         if (toAppend.length() != 0) {
 341             tokenList.add(toAppend.toString());
 342         }
 343         return tokenList;
 344     }
 345 
 346     private static int nextToken(final StreamTokenizer tokenizer) {
 347         try {
 348             return tokenizer.nextToken();
 349         } catch (final IOException ioe) {
 350             return StreamTokenizer.TT_EOF;
 351         }
 352     }
 353 
 354     /**
 355      * Compiles the given script files in the command line
 356      * This is called only when using the --compile-only flag
 357      *
 358      * @param context the nashorn context
 359      * @param global the global scope
 360      * @param files the list of script files to compile
 361      *
 362      * @return error code
 363      * @throws IOException when any script file read results in I/O error
 364      */
 365     private static int compileScripts(final Context context, final Global global, final List<String> files) throws IOException {
 366         final Global oldGlobal = Context.getGlobal();
 367         final boolean globalChanged = (oldGlobal != global);
 368         final ScriptEnvironment env = context.getEnv();
 369         try {
 370             if (globalChanged) {
 371                 Context.setGlobal(global);
 372             }
 373             final ErrorManager errors = context.getErrorManager();
 374 
 375             // For each file on the command line.
 376             for (final String fileName : files) {
 377                 final FunctionNode functionNode = new Parser(env, sourceFor(fileName, new File(fileName)), errors, env._strict, 0, context.getLogger(Parser.class)).parse();
 378 
 379                 if (errors.getNumberOfErrors() != 0) {
 380                     return COMPILATION_ERROR;
 381                 }
 382 
 383                 Compiler.forNoInstallerCompilation(
 384                        context,
 385                        functionNode.getSource(),
 386                        env._strict | functionNode.isStrict()).
 387                        compile(functionNode, CompilationPhases.COMPILE_ALL_NO_INSTALL);
 388 
 389                 if (env._print_ast) {
 390                     context.getErr().println(new ASTWriter(functionNode));
 391                 }
 392 
 393                 if (env._print_parse) {
 394                     context.getErr().println(new PrintVisitor(functionNode));
 395                 }
 396 
 397                 if (errors.getNumberOfErrors() != 0) {
 398                     return COMPILATION_ERROR;
 399                 }
 400             }
 401         } finally {
 402             env.getOut().flush();
 403             env.getErr().flush();
 404             if (globalChanged) {
 405                 Context.setGlobal(oldGlobal);
 406             }
 407         }
 408 
 409         return SUCCESS;
 410     }
 411 
 412     /**
 413      * Runs the given JavaScript files in the command line
 414      *
 415      * @param context the nashorn context
 416      * @param global the global scope
 417      * @param files the list of script files to run
 418      *
 419      * @return error code
 420      * @throws IOException when any script file read results in I/O error
 421      */
 422     private int runScripts(final Context context, final Global global, final List<String> files) throws IOException {
 423         final Global oldGlobal = Context.getGlobal();
 424         final boolean globalChanged = (oldGlobal != global);
 425         try {
 426             if (globalChanged) {
 427                 Context.setGlobal(global);
 428             }
 429             final ErrorManager errors = context.getErrorManager();
 430 
 431             // For each file on the command line.
 432             for (final String fileName : files) {
 433                 if ("-".equals(fileName)) {
 434                     final int res = readEvalPrint(context, global);
 435                     if (res != SUCCESS) {
 436                         return res;
 437                     }
 438                     continue;
 439                 }
 440 
 441                 final File file = new File(fileName);
 442                 final ScriptFunction script = context.compileScript(sourceFor(fileName, file), global);
 443                 if (script == null || errors.getNumberOfErrors() != 0) {
 444                     if (context.getEnv()._parse_only && !errors.hasErrors()) {
 445                         continue; // No error, continue to consume all files in list
 446                     }
 447                     return COMPILATION_ERROR;
 448                 }
 449 
 450                 try {
 451                     apply(script, global);
 452                 } catch (final NashornException e) {
 453                     errors.error(e.toString());
 454                     if (context.getEnv()._dump_on_error) {
 455                         e.printStackTrace(context.getErr());
 456                     }
 457 
 458                     return RUNTIME_ERROR;
 459                 }
 460             }
 461         } finally {
 462             context.getOut().flush();
 463             context.getErr().flush();
 464             if (globalChanged) {
 465                 Context.setGlobal(oldGlobal);
 466             }
 467         }
 468 
 469         return SUCCESS;
 470     }
 471 
 472     /**
 473      * Runs launches "fx:bootstrap.js" with the given JavaScript files provided
 474      * as arguments.
 475      *
 476      * @param context the nashorn context
 477      * @param global the global scope
 478      * @param files the list of script files to provide
 479      *
 480      * @return error code
 481      * @throws IOException when any script file read results in I/O error
 482      */
 483     private static int runFXScripts(final Context context, final Global global, final List<String> files) throws IOException {
 484         final Global oldGlobal = Context.getGlobal();
 485         final boolean globalChanged = (oldGlobal != global);
 486         try {
 487             if (globalChanged) {
 488                 Context.setGlobal(global);
 489             }
 490 
 491             global.addOwnProperty("$GLOBAL", Property.NOT_ENUMERABLE, global);
 492             global.addOwnProperty("$SCRIPTS", Property.NOT_ENUMERABLE, files);
 493             context.load(global, "fx:bootstrap.js");
 494         } catch (final NashornException e) {
 495             context.getErrorManager().error(e.toString());
 496             if (context.getEnv()._dump_on_error) {
 497                 e.printStackTrace(context.getErr());
 498             }
 499 
 500             return RUNTIME_ERROR;
 501         } finally {
 502             context.getOut().flush();
 503             context.getErr().flush();
 504             if (globalChanged) {
 505                 Context.setGlobal(oldGlobal);
 506             }
 507         }
 508 
 509         return SUCCESS;
 510     }
 511 
 512     /**
 513      * Hook to ScriptFunction "apply". A performance metering shell may
 514      * introduce enter/exit timing here.
 515      *
 516      * @param target target function for apply
 517      * @param self self reference for apply
 518      *
 519      * @return result of the function apply
 520      */
 521     protected Object apply(final ScriptFunction target, final Object self) {
 522         return ScriptRuntime.apply(target, self);
 523     }
 524 
 525     /**
 526      * Parse potentially partial code and keep track of the start of last expression.
 527      * This 'partial' parsing support is meant to be used for code-completion.
 528      *
 529      * @param context the nashorn context
 530      * @param code code that is to be parsed
 531      * @return the start index of the last expression parsed in the (incomplete) code.
 532      */
 533     @Override
 534     public final int getLastExpressionStart(final Context context, final String code) {
 535         final int[] exprStart = { -1 };
 536 
 537         final Parser p = new Parser(context.getEnv(), sourceFor("<partial_code>", code),new Context.ThrowErrorManager()) {
 538             @Override
 539             protected Expression expression() {
 540                 exprStart[0] = this.start;
 541                 return super.expression();
 542             }
 543 
 544             @Override
 545             protected Expression assignmentExpression(final boolean noIn) {
 546                 exprStart[0] = this.start;
 547                 return super.assignmentExpression(noIn);
 548             }
 549         };
 550 
 551         try {
 552             p.parse();
 553         } catch (final Exception ignored) {
 554             // throw any parser exception, but we are partial parsing anyway
 555         }
 556 
 557         return exprStart[0];
 558     }
 559 
 560 
 561     /**
 562      * read-eval-print loop for Nashorn shell.
 563      *
 564      * @param context the nashorn context
 565      * @param global  global scope object to use
 566      * @return return code
 567      */
 568     protected int readEvalPrint(final Context context, final Global global) {
 569         final String prompt = bundle.getString("shell.prompt");
 570         final BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
 571         final PrintWriter err = context.getErr();
 572         final Global oldGlobal = Context.getGlobal();
 573         final boolean globalChanged = (oldGlobal != global);
 574         final ScriptEnvironment env = context.getEnv();
 575 
 576         try {
 577             if (globalChanged) {
 578                 Context.setGlobal(global);
 579             }
 580 
 581             global.addShellBuiltins();
 582 
 583             while (true) {
 584                 err.print(prompt);
 585                 err.flush();
 586 
 587                 String source = "";
 588                 try {
 589                     source = in.readLine();
 590                 } catch (final IOException ioe) {
 591                     err.println(ioe.toString());
 592                 }
 593 
 594                 if (source == null) {
 595                     break;
 596                 }
 597 
 598                 if (source.isEmpty()) {
 599                     continue;
 600                 }
 601 
 602                 try {
 603                     final Object res = context.eval(global, source, global, "<shell>");
 604                     if (res != ScriptRuntime.UNDEFINED) {
 605                         err.println(toString(res, global));
 606                     }
 607                 } catch (final Exception e) {
 608                     err.println(e);
 609                     if (env._dump_on_error) {
 610                         e.printStackTrace(err);
 611                     }
 612                 }
 613             }
 614         } finally {
 615             if (globalChanged) {
 616                 Context.setGlobal(oldGlobal);
 617             }
 618         }
 619 
 620         return SUCCESS;
 621     }
 622 
 623     /**
 624      * Converts {@code result} to a printable string. The reason we don't use {@link JSType#toString(Object)}
 625      * or {@link ScriptRuntime#safeToString(Object)} is that we want to be able to render Symbol values
 626      * even if they occur within an Array, and therefore have to implement our own Array to String
 627      * conversion.
 628      *
 629      * @param result the result
 630      * @param global the global object
 631      * @return the string representation
 632      */
 633     protected static String toString(final Object result, final Global global) {
 634         if (result instanceof Symbol) {
 635             // Normal implicit conversion of symbol to string would throw TypeError
 636             return result.toString();
 637         }
 638 
 639         if (result instanceof NativeSymbol) {
 640             return JSType.toPrimitive(result).toString();
 641         }
 642 
 643         if (isArrayWithDefaultToString(result, global)) {
 644             // This should yield the same string as Array.prototype.toString but
 645             // will not throw if the array contents include symbols.
 646             final StringBuilder sb = new StringBuilder();
 647             final Iterator<Object> iter = ArrayLikeIterator.arrayLikeIterator(result, true);
 648 
 649             while (iter.hasNext()) {
 650                 final Object obj = iter.next();
 651 
 652                 if (obj != null && obj != ScriptRuntime.UNDEFINED) {
 653                     sb.append(toString(obj, global));
 654                 }
 655 
 656                 if (iter.hasNext()) {
 657                     sb.append(',');
 658                 }
 659             }
 660 
 661             return sb.toString();
 662         }
 663 
 664         return JSType.toString(result);
 665     }
 666 
 667     private static boolean isArrayWithDefaultToString(final Object result, final Global global) {
 668         if (result instanceof ScriptObject) {
 669             final ScriptObject sobj = (ScriptObject) result;
 670             return sobj.isArray() && sobj.get("toString") == global.getArrayPrototype().get("toString");
 671         }
 672         return false;
 673     }
 674 }