jdk.nashorn.api.scripting.NashornScriptEngineFactory Java Examples

@Test
public void factoryOptionsTest() {
    final ScriptEngineManager sm = new ScriptEngineManager();
    for (final ScriptEngineFactory fac : sm.getEngineFactories()) {
        if (fac instanceof NashornScriptEngineFactory) {
            final NashornScriptEngineFactory nfac = (NashornScriptEngineFactory)fac;
            // specify --no-syntax-extensions flag
            final String[] options = new String[] { "--no-syntax-extensions" };
            final ScriptEngine e = nfac.getScriptEngine(options);
            try {
                // try nashorn specific extension
                e.eval("var f = funtion(x) 2*x;");
                fail("should have thrown exception!");
            } catch (final Exception ex) {
                //empty
            }
            return;
        }
    }

    fail("Cannot find nashorn factory!");
}
 

public void runExternalJsTest() {
    final String[] paths = new String[]{
            "test/script/basic/compile-octane.js",
            "test/script/basic/jquery.js",
            "test/script/basic/prototype.js",
            "test/script/basic/runsunspider.js",
            "test/script/basic/underscore.js",
            "test/script/basic/yui.js",
            "test/script/basic/run-octane.js"
    };
    final NashornScriptEngineFactory factory = new NashornScriptEngineFactory();
    for (final String path : paths) {
        final ScriptEngine engine = factory.getScriptEngine(new String[]{"-scripting"}, getClass().getClassLoader(), getClassFilter());
        try {
            engine.eval(new URLReader(new File(path).toURI().toURL()));
        } catch (final Exception e) {
            fail("Script " + path + " fails with exception :" + e.getMessage());
        }
    }
}
 

/**
 * Test access to global lexically declared variables for shared script classes with single global.
 */
@Test
public static void megamorphicSingleGlobalLetTest() throws ScriptException, InterruptedException {
    final NashornScriptEngineFactory factory = new NashornScriptEngineFactory();
    final ScriptEngine e = factory.getScriptEngine(LANGUAGE_ES6);
    final String sharedGetterScript = "foo";
    final String sharedSetterScript = "foo = 1";

    for (int i = 0; i < MEGAMORPHIC_LOOP_COUNT; i++) {
        assertEquals(e.eval(sharedSetterScript), 1);
        assertEquals(e.eval(sharedGetterScript), 1);
        assertEquals(e.eval("delete foo; a" + i + " = 1; foo = " + i + ";"), i);
        assertEquals(e.eval(sharedGetterScript), i);
    }

    assertEquals(e.eval("let foo = 'foo';"), null);
    assertEquals(e.eval(sharedGetterScript), "foo");
    assertEquals(e.eval(sharedSetterScript), 1);
    assertEquals(e.eval(sharedGetterScript), 1);
    assertEquals(e.eval("this.foo"), MEGAMORPHIC_LOOP_COUNT - 1);
}
 

@Test
public void pathHandlingTest() {
    System.setProperty("nashorn.persistent.code.cache", codeCache);
    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();

    fac.getScriptEngine(ENGINE_OPTIONS_NOOPT);

    final Path expectedCodeCachePath = FileSystems.getDefault().getPath(oldUserDir + File.separator + codeCache);
    final Path actualCodeCachePath = FileSystems.getDefault().getPath(System.getProperty(
                        "nashorn.persistent.code.cache")).toAbsolutePath();
    // Check that nashorn code cache is created in current working directory
    assertEquals(actualCodeCachePath, expectedCodeCachePath);
    // Check that code cache dir exists and it's not empty
    final File file = new File(actualCodeCachePath.toUri());
    assertFalse(!file.isDirectory(), "No code cache directory was created!");
    assertFalse(file.list().length == 0, "Code cache directory is empty!");
}
 

@Test
public void changeUserDirTest() throws ScriptException, IOException {
    System.setProperty("nashorn.persistent.code.cache", codeCache);
    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();
    final ScriptEngine e = fac.getScriptEngine(ENGINE_OPTIONS_NOOPT);
    final Path codeCachePath = getCodeCachePath(false);
    final String newUserDir = "build/newUserDir";
    // Now changing current working directory
    System.setProperty("user.dir", System.getProperty("user.dir") + File.separator + newUserDir);
    try {
        // Check that a new compiled script is stored in existing code cache
        e.eval(code1);
        final DirectoryStream<Path> stream = Files.newDirectoryStream(codeCachePath);
        checkCompiledScripts(stream, 1);
        // Setting to default current working dir
    } finally {
        System.setProperty("user.dir", oldUserDir);
    }
}
 

@Test
public void changeUserDirTest() throws ScriptException, IOException {
    System.setProperty("nashorn.persistent.code.cache", codeCache);
    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();
    final ScriptEngine e = fac.getScriptEngine(ENGINE_OPTIONS_NOOPT);
    final Path codeCachePath = getCodeCachePath(false);
    final String newUserDir = "build/newUserDir";
    // Now changing current working directory
    System.setProperty("user.dir", System.getProperty("user.dir") + File.separator + newUserDir);
    try {
        // Check that a new compiled script is stored in existing code cache
        e.eval(code1);
        final DirectoryStream<Path> stream = Files.newDirectoryStream(codeCachePath);
        checkCompiledScripts(stream, 1);
        // Setting to default current working dir
    } finally {
        System.setProperty("user.dir", oldUserDir);
    }
}
 

@Test
public void classFilterTest2() throws ScriptException {
    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();
    final ScriptEngine e = fac.getScriptEngine(new String[0], Thread.currentThread().getContextClassLoader(),
        new ClassFilter() {
            @Override
            public boolean exposeToScripts(final String fullName) {
                // don't allow anything that is not "java."
                return fullName.startsWith("java.");
            }
        });

    assertEquals(e.eval("typeof javax.script.ScriptEngine"), "object");
    assertEquals(e.eval("typeof java.util.Vector"), "function");

    try {
        e.eval("Java.type('javax.script.ScriptContext')");
        fail("should not reach here");
    } catch (final ScriptException | RuntimeException se) {
        if (! (se.getCause() instanceof ClassNotFoundException)) {
            fail("ClassNotFoundException expected");
        }
    }
}
 

@Test
public void evalFileNameWithSpecialCharsTest() throws ScriptException {
    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();
    final ScriptEngine engine = fac.getScriptEngine(new String[] { "--verify-code=true" });
    final ScriptContext ctxt = new SimpleScriptContext();
    // use file name with "dangerous" chars.
    ctxt.setAttribute(ScriptEngine.FILENAME, "<myscript>", ScriptContext.ENGINE_SCOPE);
    engine.eval("var a = 3;");
    ctxt.setAttribute(ScriptEngine.FILENAME, "[myscript]", ScriptContext.ENGINE_SCOPE);
    engine.eval("var h = 'hello';");
    ctxt.setAttribute(ScriptEngine.FILENAME, ";/\\$.", ScriptContext.ENGINE_SCOPE);
    engine.eval("var foo = 'world';");
    // name used by jjs shell tool for the interactive mode
    ctxt.setAttribute(ScriptEngine.FILENAME, "<shell>", ScriptContext.ENGINE_SCOPE);
    engine.eval("var foo = 'world';");
}
 

@Test
public void evalFileNameWithSpecialCharsTest() throws ScriptException {
    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();
    final ScriptEngine engine = fac.getScriptEngine(new String[] { "--verify-code=true" });
    final ScriptContext ctxt = new SimpleScriptContext();
    // use file name with "dangerous" chars.
    ctxt.setAttribute(ScriptEngine.FILENAME, "<myscript>", ScriptContext.ENGINE_SCOPE);
    engine.eval("var a = 3;");
    ctxt.setAttribute(ScriptEngine.FILENAME, "[myscript]", ScriptContext.ENGINE_SCOPE);
    engine.eval("var h = 'hello';");
    ctxt.setAttribute(ScriptEngine.FILENAME, ";/\\$.", ScriptContext.ENGINE_SCOPE);
    engine.eval("var foo = 'world';");
    // name used by jjs shell tool for the interactive mode
    ctxt.setAttribute(ScriptEngine.FILENAME, "<shell>", ScriptContext.ENGINE_SCOPE);
    engine.eval("var foo = 'world';");
}
 

@Test
public void nashornConfigSecurityTest() {
    if (System.getSecurityManager() == null) {
        // pass vacuously
        return;
    }

    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();
    try {
        fac.getScriptEngine(new ClassFilter() {
           @Override
           public boolean exposeToScripts(final String name) {
               return true;
           }
        });
        fail("SecurityException should have been thrown");
    } catch (final SecurityException e) {
        //empty
    }
}
 

@Test
public void nashornConfigSecurityTest2() {
    if (System.getSecurityManager() == null) {
        // pass vacuously
        return;
    }

    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();
    try {
        fac.getScriptEngine(new String[0], null, new ClassFilter() {
           @Override
           public boolean exposeToScripts(final String name) {
               return true;
           }
        });
        fail("SecurityException should have been thrown");
    } catch (final SecurityException e) {
        //empty
    }
}
 

/**
 * Test access to global lexically declared variables for shared script classes with single global.
 */
@Test
public static void megamorphicSingleGlobalLetTest() throws ScriptException, InterruptedException {
    final NashornScriptEngineFactory factory = new NashornScriptEngineFactory();
    final ScriptEngine e = factory.getScriptEngine(LANGUAGE_ES6);
    final String sharedGetterScript = "foo";
    final String sharedSetterScript = "foo = 1";

    for (int i = 0; i < MEGAMORPHIC_LOOP_COUNT; i++) {
        assertEquals(e.eval(sharedSetterScript), 1);
        assertEquals(e.eval(sharedGetterScript), 1);
        assertEquals(e.eval("delete foo; a" + i + " = 1; foo = " + i + ";"), i);
        assertEquals(e.eval(sharedGetterScript), i);
    }

    assertEquals(e.eval("let foo = 'foo';"), null);
    assertEquals(e.eval(sharedGetterScript), "foo");
    assertEquals(e.eval(sharedSetterScript), 1);
    assertEquals(e.eval(sharedGetterScript), 1);
    assertEquals(e.eval("this.foo"), MEGAMORPHIC_LOOP_COUNT - 1);
}
 

@Test
public void pathHandlingTest() {
    System.setProperty("nashorn.persistent.code.cache", codeCache);
    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();

    fac.getScriptEngine(ENGINE_OPTIONS_NOOPT);

    final Path expectedCodeCachePath = FileSystems.getDefault().getPath(oldUserDir + File.separator + codeCache);
    final Path actualCodeCachePath = FileSystems.getDefault().getPath(System.getProperty(
                        "nashorn.persistent.code.cache")).toAbsolutePath();
    // Check that nashorn code cache is created in current working directory
    assertEquals(actualCodeCachePath, expectedCodeCachePath);
    // Check that code cache dir exists and it's not empty
    final File file = new File(actualCodeCachePath.toUri());
    assertFalse(!file.isDirectory(), "No code cache directory was created!");
    assertFalse(file.list().length == 0, "Code cache directory is empty!");
}
 

@Test
public void changeUserDirTest() throws ScriptException, IOException {
    System.setProperty("nashorn.persistent.code.cache", codeCache);
    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();
    final ScriptEngine e = fac.getScriptEngine(ENGINE_OPTIONS_NOOPT);
    final Path codeCachePath = getCodeCachePath(false);
    final String newUserDir = "build/newUserDir";
    // Now changing current working directory
    System.setProperty("user.dir", System.getProperty("user.dir") + File.separator + newUserDir);
    try {
        // Check that a new compiled script is stored in existing code cache
        e.eval(code1);
        final DirectoryStream<Path> stream = Files.newDirectoryStream(codeCachePath);
        checkCompiledScripts(stream, 1);
        // Setting to default current working dir
    } finally {
        System.setProperty("user.dir", oldUserDir);
    }
}
 

@Test
public void factoryClassLoaderTest() {
    final ScriptEngineManager sm = new ScriptEngineManager();
    for (final ScriptEngineFactory fac : sm.getEngineFactories()) {
        if (fac instanceof NashornScriptEngineFactory) {
            final NashornScriptEngineFactory nfac = (NashornScriptEngineFactory)fac;
            final MyClassLoader loader = new MyClassLoader();
            // set the classloader as app class loader
            final ScriptEngine e = nfac.getScriptEngine(loader);
            try {
                e.eval("Packages.foo");
                // check that the class loader was attempted
                assertTrue(loader.reached(), "did not reach class loader!");
            } catch (final ScriptException se) {
                se.printStackTrace();
                fail(se.getMessage());
            }
            return;
        }
    }

    fail("Cannot find nashorn factory!");
}
 

/**
 * Test access to global lexically declared variables for shared script classes with single global.
 */
@Test
public static void megamorphicInheritedGlobalLetTest() throws ScriptException, InterruptedException {
    final NashornScriptEngineFactory factory = new NashornScriptEngineFactory();
    final ScriptEngine e = factory.getScriptEngine(LANGUAGE_ES6);
    final String sharedGetterScript = "foo";
    final String sharedSetterScript = "foo = 1";

    for (int i = 0; i < MEGAMORPHIC_LOOP_COUNT; i++) {
        assertEquals(e.eval(sharedSetterScript), 1);
        assertEquals(e.eval(sharedGetterScript), 1);
        assertEquals(e.eval("delete foo; a" + i + " = 1; Object.prototype.foo = " + i + ";"), i);
        assertEquals(e.eval(sharedGetterScript), i);
    }

    assertEquals(e.eval("let foo = 'foo';"), null);
    assertEquals(e.eval(sharedGetterScript), "foo");
    assertEquals(e.eval(sharedSetterScript), 1);
    assertEquals(e.eval(sharedGetterScript), 1);
    assertEquals(e.eval("this.foo"), MEGAMORPHIC_LOOP_COUNT - 1);
}
 

@Test
/**
 * Test repeated evals with --loader-per-compile=false
 * We used to get "class redefinition error".
 */
public void noLoaderPerCompilerTest() {
    final ScriptEngineManager sm = new ScriptEngineManager();
    for (final ScriptEngineFactory fac : sm.getEngineFactories()) {
        if (fac instanceof NashornScriptEngineFactory) {
            final NashornScriptEngineFactory nfac = (NashornScriptEngineFactory)fac;
            final String[] options = new String[] { "--loader-per-compile=false" };
            final ScriptEngine e = nfac.getScriptEngine(options);
            try {
                e.eval("2 + 3");
                e.eval("4 + 4");
            } catch (final ScriptException se) {
                se.printStackTrace();
                fail(se.getMessage());
            }
            return;
        }
    }
    fail("Cannot find nashorn factory!");
}
 

@Test
/**
 * Test that we can use same script name in repeated evals with --loader-per-compile=false
 * We used to get "class redefinition error" as name was derived from script name.
 */
public void noLoaderPerCompilerWithSameNameTest() {
    final ScriptEngineManager sm = new ScriptEngineManager();
    for (final ScriptEngineFactory fac : sm.getEngineFactories()) {
        if (fac instanceof NashornScriptEngineFactory) {
            final NashornScriptEngineFactory nfac = (NashornScriptEngineFactory)fac;
            final String[] options = new String[] { "--loader-per-compile=false" };
            final ScriptEngine e = nfac.getScriptEngine(options);
            e.put(ScriptEngine.FILENAME, "test.js");
            try {
                e.eval("2 + 3");
                e.eval("4 + 4");
            } catch (final ScriptException se) {
                se.printStackTrace();
                fail(se.getMessage());
            }
            return;
        }
    }
    fail("Cannot find nashorn factory!");
}
 

@Test
public void globalPerEngineTest() throws ScriptException {
    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();
    final String[] options = new String[] { "--global-per-engine" };
    final ScriptEngine e = fac.getScriptEngine(options);

    e.eval("function foo() {}");

    final ScriptContext newCtx = new SimpleScriptContext();
    newCtx.setBindings(e.createBindings(), ScriptContext.ENGINE_SCOPE);

    // all global definitions shared and so 'foo' should be
    // visible in new Bindings as well.
    assertTrue(e.eval("typeof foo", newCtx).equals("function"));

    e.eval("function bar() {}", newCtx);

    // bar should be visible in default context
    assertTrue(e.eval("typeof bar").equals("function"));
}
 

@Test
public void classFilterTest() throws ScriptException {
    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();
    final ScriptEngine e = fac.getScriptEngine(new ClassFilter() {
        @Override
        public boolean exposeToScripts(final String fullName) {
            // don't allow anything that is not "java."
            return fullName.startsWith("java.");
        }
    });

    assertEquals(e.eval("typeof javax.script.ScriptEngine"), "object");
    assertEquals(e.eval("typeof java.util.Vector"), "function");

    try {
        e.eval("Java.type('javax.script.ScriptContext')");
        fail("should not reach here");
    } catch (final ScriptException | RuntimeException se) {
        if (! (se.getCause() instanceof ClassNotFoundException)) {
            fail("ClassNotFoundException expected");
        }
    }
}
 

@Test
public void classFilterTest2() throws ScriptException {
    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();
    final ScriptEngine e = fac.getScriptEngine(new String[0], Thread.currentThread().getContextClassLoader(),
        new ClassFilter() {
            @Override
            public boolean exposeToScripts(final String fullName) {
                // don't allow anything that is not "java."
                return fullName.startsWith("java.");
            }
        });

    assertEquals(e.eval("typeof javax.script.ScriptEngine"), "object");
    assertEquals(e.eval("typeof java.util.Vector"), "function");

    try {
        e.eval("Java.type('javax.script.ScriptContext')");
        fail("should not reach here");
    } catch (final ScriptException | RuntimeException se) {
        if (! (se.getCause() instanceof ClassNotFoundException)) {
            fail("ClassNotFoundException expected");
        }
    }
}
 

@Test
public void pathHandlingTest() {
    System.setProperty("nashorn.persistent.code.cache", codeCache);
    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();

    fac.getScriptEngine(ENGINE_OPTIONS_NOOPT);

    final Path expectedCodeCachePath = FileSystems.getDefault().getPath(oldUserDir + File.separator + codeCache);
    final Path actualCodeCachePath = FileSystems.getDefault().getPath(System.getProperty(
                        "nashorn.persistent.code.cache")).toAbsolutePath();
    // Check that nashorn code cache is created in current working directory
    assertEquals(actualCodeCachePath, expectedCodeCachePath);
    // Check that code cache dir exists and it's not empty
    final File file = new File(actualCodeCachePath.toUri());
    assertFalse(!file.isDirectory(), "No code cache directory was created!");
    assertFalse(file.list().length == 0, "Code cache directory is empty!");
}
 

@Test
public void evalFileNameWithSpecialCharsTest() throws ScriptException {
    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();
    final ScriptEngine engine = fac.getScriptEngine(new String[] { "--verify-code=true" });
    final ScriptContext ctxt = new SimpleScriptContext();
    // use file name with "dangerous" chars.
    ctxt.setAttribute(ScriptEngine.FILENAME, "<myscript>", ScriptContext.ENGINE_SCOPE);
    engine.eval("var a = 3;");
    ctxt.setAttribute(ScriptEngine.FILENAME, "[myscript]", ScriptContext.ENGINE_SCOPE);
    engine.eval("var h = 'hello';");
    ctxt.setAttribute(ScriptEngine.FILENAME, ";/\\$.", ScriptContext.ENGINE_SCOPE);
    engine.eval("var foo = 'world';");
    // name used by jjs shell tool for the interactive mode
    ctxt.setAttribute(ScriptEngine.FILENAME, "<shell>", ScriptContext.ENGINE_SCOPE);
    engine.eval("var foo = 'world';");
}
 

@Test
public void globalPerEngineTest() throws ScriptException {
    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();
    final String[] options = new String[] { "--global-per-engine" };
    final ScriptEngine e = fac.getScriptEngine(options);

    e.eval("function foo() {}");

    final ScriptContext newCtx = new SimpleScriptContext();
    newCtx.setBindings(e.createBindings(), ScriptContext.ENGINE_SCOPE);

    // all global definitions shared and so 'foo' should be
    // visible in new Bindings as well.
    assertTrue(e.eval("typeof foo", newCtx).equals("function"));

    e.eval("function bar() {}", newCtx);

    // bar should be visible in default context
    assertTrue(e.eval("typeof bar").equals("function"));
}
 

public void runExternalJsTest() {
    final String[] paths = new String[]{
            "test/script/basic/compile-octane.js",
            "test/script/basic/jquery.js",
            "test/script/basic/prototype.js",
            "test/script/basic/runsunspider.js",
            "test/script/basic/underscore.js",
            "test/script/basic/yui.js",
            "test/script/basic/run-octane.js"
    };
    final NashornScriptEngineFactory factory = new NashornScriptEngineFactory();
    for (final String path : paths) {
        final ScriptEngine engine = factory.getScriptEngine(new String[]{"-scripting"}, getClass().getClassLoader(), getClassFilter());
        try {
            engine.eval(new URLReader(new File(path).toURI().toURL()));
        } catch (final Exception e) {
            fail("Script " + path + " fails with exception :" + e.getMessage());
        }
    }
}
 

@Test
public void nashornConfigSecurityTest2() {
    if (System.getSecurityManager() == null) {
        // pass vacuously
        return;
    }

    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();
    try {
        fac.getScriptEngine(new String[0], null, new ClassFilter() {
           @Override
           public boolean exposeToScripts(final String name) {
               return true;
           }
        });
        fail("SecurityException should have been thrown");
    } catch (final SecurityException e) {
        //empty
    }
}
 

@Test
public void megamorphicPropertyReadTest() throws ScriptException {
    final NashornScriptEngineFactory factory = new NashornScriptEngineFactory();
    final ScriptEngine engine = factory.getScriptEngine();
    final Bindings scope = engine.getBindings(ScriptContext.ENGINE_SCOPE);
    boolean ret;

    // Why 16 is the upper limit of this loop? The default nashorn dynalink megamorphic threshold is 16.
    // See jdk.nashorn.internal.runtime.linker.Bootstrap.NASHORN_DEFAULT_UNSTABLE_RELINK_THRESHOLD
    // We do, 'eval' of the same in this loop twice. So, 16*2 = 32 times that callsite in the script
    // is exercised - much beyond the default megamorphic threshold.

    for (int i = 0; i < 16; i++) {
        scope.remove(VAR_NAME);
        ret = lookupVar(engine, VAR_NAME);
        assertFalse(ret, "Expected false in iteration " + i);
        scope.put(VAR_NAME, "foo");
        ret = lookupVar(engine, VAR_NAME);
        assertTrue(ret, "Expected true in iteration " + i);
    }
}
 

@Test
public void classFilterTest() throws ScriptException {
    final NashornScriptEngineFactory fac = new NashornScriptEngineFactory();
    final ScriptEngine e = fac.getScriptEngine(new ClassFilter() {
        @Override
        public boolean exposeToScripts(final String fullName) {
            // don't allow anything that is not "java."
            return fullName.startsWith("java.");
        }
    });

    assertEquals(e.eval("typeof javax.script.ScriptEngine"), "object");
    assertEquals(e.eval("typeof java.util.Vector"), "function");

    try {
        e.eval("Java.type('javax.script.ScriptContext')");
        fail("should not reach here");
    } catch (final ScriptException | RuntimeException se) {
        if (! (se.getCause() instanceof ClassNotFoundException)) {
            fail("ClassNotFoundException expected");
        }
    }
}
 

/**
 * Ensure that the old behaviour (every object is a Map) is unchanged.
 */
@Test
public void testNonWrapping() throws ScriptException {
    final ScriptEngine engine = new NashornScriptEngineFactory().getScriptEngine();
    final Object val = engine.eval("({x: [1, {y: [2, {z: [3]}]}, [4, 5]]})");
    final Map<String, Object> root = asMap(val);
    final Map<String, Object> x = asMap(root.get("x"));
    assertEquals(x.get("0"), 1);
    final Map<String, Object> x1 = asMap(x.get("1"));
    final Map<String, Object> y = asMap(x1.get("y"));
    assertEquals(y.get("0"), 2);
    final Map<String, Object> y1 = asMap(y.get("1"));
    final Map<String, Object> z = asMap(y1.get("z"));
    assertEquals(z.get("0"), 3);
    final Map<String, Object> x2 = asMap(x.get("2"));
    assertEquals(x2.get("0"), 4);
    assertEquals(x2.get("1"), 5);
}
 

/**
 * Test access to global lexically declared variables for shared script classes with single global.
 */
@Test
public static void megamorphicSingleGlobalLetTest() throws ScriptException, InterruptedException {
    final NashornScriptEngineFactory factory = new NashornScriptEngineFactory();
    final ScriptEngine e = factory.getScriptEngine(LANGUAGE_ES6);
    final String sharedGetterScript = "foo";
    final String sharedSetterScript = "foo = 1";

    for (int i = 0; i < MEGAMORPHIC_LOOP_COUNT; i++) {
        assertEquals(e.eval(sharedSetterScript), 1);
        assertEquals(e.eval(sharedGetterScript), 1);
        assertEquals(e.eval("delete foo; a" + i + " = 1; foo = " + i + ";"), i);
        assertEquals(e.eval(sharedGetterScript), i);
    }

    assertEquals(e.eval("let foo = 'foo';"), null);
    assertEquals(e.eval(sharedGetterScript), "foo");
    assertEquals(e.eval(sharedSetterScript), 1);
    assertEquals(e.eval(sharedGetterScript), 1);
    assertEquals(e.eval("this.foo"), MEGAMORPHIC_LOOP_COUNT - 1);
}