Update JSScript SPI based on feedback

https://bugs.webkit.org/show_bug.cgi?id=194517

Reviewed by Keith Miller.

This patch updates the JSScript SPI in the following ways:
- JSScript can now represent both modules and programs. This is a property
of the script determined during creation.
- JSScript now takes a sourceURL during construction. For modules, this acts
as the module identifier.
- JSScript now has SPI for writing the cache out to disk. We don't do this
automatically.
- JSScript will load the bytecode cache on creation if it exists.
- We retrofit these new requirements on the prior JSScript SPI that
we're going to remove as soon as we can: https://bugs.webkit.org/show_bug.cgi?id=194909.
Previous SPI assumes all JSScripts are modules. Previous SPI also assigns
a sourceURL to the JSScript based on what the module loader decided the
identifier should be. We'll remove this once we remove the old SPI.

This patch also adds SPI to JSContext to evaluate a JSScript. For modules,
this is like returning the result of doing dynamic import. For programs,
this does normal program evaluation.

This patch also fixes a bug in generateBytecode/generateModuleBytecode where
we would try to cache the bytecode even if recursivelyGenerateUnlinkedCodeBlock
returned null. E.g, if the script had a syntax error.

When writing tests, I also discovered that someone previously broke
testapi. This patch also fixes those failures. They were broken when
we switched to using a testapiScripts directory to hold our test .js
scripts.

* API/JSAPIGlobalObject.h:
* API/JSAPIGlobalObject.mm:
(JSC::JSAPIGlobalObject::moduleLoaderResolve):
(JSC::JSAPIGlobalObject::moduleLoaderFetch):
(JSC::JSAPIGlobalObject::loadAndEvaluateJSScriptModule):
* API/JSBase.cpp:
(JSEvaluateScriptInternal):
(JSEvaluateScript):
* API/JSBaseInternal.h: Added.
* API/JSContext.mm:
(-[JSContext evaluateScript:withSourceURL:]):
(-[JSContext evaluateJSScript:]):
* API/JSContextPrivate.h:
* API/JSScript.h:
* API/JSScript.mm:
(+[JSScript scriptWithSource:inVirtualMachine:]):
(+[JSScript scriptFromASCIIFile:inVirtualMachine:withCodeSigning:andBytecodeCache:]):
(createError):
(+[JSScript scriptOfType:inVirtualMachine:withSourceURL:andSource:andBytecodeCache:error:]):
(+[JSScript scriptOfType:inVirtualMachine:memoryMappedFromASCIIFile:withSourceURL:andBytecodeCache:error:]):
(-[JSScript cacheBytecodeWithError:]):
(-[JSScript sourceURL]):
(-[JSScript type]):
(-[JSScript jsSourceCode]):
(-[JSScript writeCache:]):
(-[JSScript setSourceURL:]):
(-[JSScript forceRecreateJSSourceCode]):
(-[JSScript writeCache]): Deleted.
(-[JSScript jsSourceCode:]): Deleted.
* API/JSScriptInternal.h:
* API/tests/FunctionOverridesTest.cpp:
(testFunctionOverrides):
* API/tests/testapi.c:
(main):
* API/tests/testapi.mm:
(tempFile):
(testModuleBytecodeCache):
(testProgramBytecodeCache):
(testBytecodeCacheWithSyntaxError):
(testProgramJSScriptException):
(testLoadBasicFileLegacySPI):
(+[JSContextMemoryMappedLoaderDelegate newContext]):
(-[JSContextMemoryMappedLoaderDelegate context:fetchModuleForIdentifier:withResolveHandler:andRejectHandler:]):
(testLoadBasicFile):
(+[JSContextAugmentedLoaderDelegate newContext]):
(-[JSContextAugmentedLoaderDelegate context:fetchModuleForIdentifier:withResolveHandler:andRejectHandler:]):
(testJSScriptURL):
(testObjectiveCAPI):
(testBytecodeCache): Deleted.
* API/tests/testapiScripts/foo.js: Added.
* JavaScriptCore.xcodeproj/project.pbxproj:
* runtime/Completion.cpp:
(JSC::generateBytecode):
(JSC::generateModuleBytecode):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@241929 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Author: [email protected]

Source/JavaScriptCore/API/JSAPIGlobalObject.h

@@ -27,6 +27,8 @@
 
 #include "JSGlobalObject.h"
 
+OBJC_CLASS JSScript;
+
 namespace JSC {
 
 class JSAPIGlobalObject : public JSGlobalObject {
@@ -55,6 +57,8 @@ class JSAPIGlobalObject : public JSGlobalObject {
     static JSInternalPromise* moduleLoaderFetch(JSGlobalObject*, ExecState*, JSModuleLoader*, JSValue, JSValue, JSValue);
     static JSObject* moduleLoaderCreateImportMetaProperties(JSGlobalObject*, ExecState*, JSModuleLoader*, JSValue, JSModuleRecord*, JSValue);
 
+    JSValue loadAndEvaluateJSScriptModule(const JSLockHolder&, JSScript *);
+
 private:
     JSAPIGlobalObject(VM& vm, Structure* structure)
         : Base(vm, structure, &s_globalObjectMethodTable)

Source/JavaScriptCore/API/JSAPIGlobalObject.mm

@@ -34,16 +34,17 @@
 #import "Error.h"
 #import "Exception.h"
 #import "JSContextInternal.h"
+#import "JSInternalPromise.h"
 #import "JSInternalPromiseDeferred.h"
 #import "JSNativeStdFunction.h"
+#import "JSPromiseDeferred.h"
 #import "JSScriptInternal.h"
 #import "JSSourceCode.h"
 #import "JSValueInternal.h"
 #import "JSVirtualMachineInternal.h"
 #import "JavaScriptCore.h"
 #import "ObjectConstructor.h"
 #import "SourceOrigin.h"
-
 #import <wtf/URL.h>
 
 namespace JSC {
@@ -75,12 +76,20 @@
     ASSERT(key.isString() || key.isSymbol());
     String name =  key.toWTFString(exec);
 
-    URL referrerURL(URL(), jsCast<JSString*>(referrer)->tryGetValue());
-    RELEASE_ASSERT(referrerURL.isValid());
-
-    URL url = URL(referrerURL, name);
-    if (url.isValid())
-        return Identifier::fromString(exec, url);
+    if (JSString* referrerString = jsDynamicCast<JSString*>(vm, referrer)) {
+        String value = referrerString->value(exec);
+        URL referrerURL({ }, value);
+        RETURN_IF_EXCEPTION(scope, { });
+        RELEASE_ASSERT(referrerURL.isValid());
+
+        URL url = URL(referrerURL, name);
+        if (url.isValid())
+            return Identifier::fromString(exec, url);
+    } else {
+        URL url = URL({ }, name);
+        if (url.isValid())
+            return Identifier::fromString(exec, url);
+    }
 
     throwVMError(exec, scope, "Could not form valid URL from identifier and base"_s);
     return { };
@@ -162,20 +171,43 @@
         return deferred->reject(exec, createError(exec, "No module loader provided."));
 
     auto deferredPromise = Strong<JSInternalPromiseDeferred>(vm, deferred);
-    auto strongKey = Strong<JSString>(vm, jsSecureCast<JSString*>(vm, key));
     auto* resolve = JSNativeStdFunction::create(vm, globalObject, 1, "resolve", [=] (ExecState* exec) {
         // This captures the globalObject but that's ok because our structure keeps it alive anyway.
+        VM& vm = exec->vm();
         JSContext *context = [JSContext contextWithJSGlobalContextRef:toGlobalRef(globalObject->globalExec())];
         id script = valueToObject(context, toRef(exec, exec->argument(0)));
 
         MarkedArgumentBuffer args;
-        if (UNLIKELY(![script isKindOfClass:[JSScript class]])) {
-            args.append(createTypeError(exec, "First argument of resolution callback is not a JSScript"));
+
+        auto rejectPromise = [&] (String message) {
+            args.append(createTypeError(exec, message));
             call(exec, deferredPromise->JSPromiseDeferred::reject(), args, "This should never be seen...");
             return encodedJSUndefined();
+        };
+
+        if (UNLIKELY(![script isKindOfClass:[JSScript class]]))
+            return rejectPromise("First argument of resolution callback is not a JSScript"_s);
+
+        JSScript* jsScript = static_cast<JSScript *>(script);
+
+        JSSourceCode* source = [jsScript jsSourceCode];
+        if (UNLIKELY([jsScript type] != kJSScriptTypeModule))
+            return rejectPromise("The JSScript that was provided did not have expected type of kJSScriptTypeModule."_s);
+
+        // FIXME: The SPI we're deprecating did not require sourceURL, so we just
+        // ignore this check for such use cases until we can remove that SPI. Once
+        // we do that, we can remove the null check for sourceURL:
+        // https://bugs.webkit.org/show_bug.cgi?id=194909
+        if (NSURL *sourceURL = [jsScript sourceURL]) {
+            String oldModuleKey { [sourceURL absoluteString] };
+            if (UNLIKELY(Identifier::fromString(&vm, oldModuleKey) != moduleKey))
+                return rejectPromise(makeString("The same JSScript was provided for two different identifiers, previously: ", oldModuleKey, " and now: ", moduleKey.string()));
+        } else {
+            [jsScript setSourceURL:[NSURL URLWithString:static_cast<NSString *>(moduleKey.string())]];
+            source = [jsScript forceRecreateJSSourceCode];
         }
 
-        args.append([static_cast<JSScript *>(script) jsSourceCode:moduleKey]);
+        args.append(source);
         call(exec, deferredPromise->JSPromiseDeferred::resolve(), args, "This should never be seen...");
         return encodedJSUndefined();
     });
@@ -210,6 +242,22 @@
     return metaProperties;
 }
 
+JSValue JSAPIGlobalObject::loadAndEvaluateJSScriptModule(const JSLockHolder&, JSScript *script)
+{
+    ASSERT(script.type == kJSScriptTypeModule);
+    VM& vm = this->vm();
+    ExecState* exec = globalExec();
+    auto scope = DECLARE_THROW_SCOPE(vm);
+
+    Identifier key = Identifier::fromString(exec, String { [[script sourceURL] absoluteString] });
+    JSInternalPromise* promise = importModule(exec, key, jsUndefined(), jsUndefined());
+    RETURN_IF_EXCEPTION(scope, { });
+    auto result = JSPromiseDeferred::tryCreate(exec, this);
+    RETURN_IF_EXCEPTION(scope, { });
+    result->resolve(exec, promise);
+    return result->promise();
+}
+
 }
 
 #endif // JSC_OBJC_API_ENABLED

Source/JavaScriptCore/API/JSBase.cpp

@@ -25,6 +25,7 @@
 
 #include "config.h"
 #include "JSBase.h"
+#include "JSBaseInternal.h"
 #include "JSBasePrivate.h"
 
 #include "APICast.h"
@@ -47,25 +48,15 @@
 
 using namespace JSC;
 
-JSValueRef JSEvaluateScript(JSContextRef ctx, JSStringRef script, JSObjectRef thisObject, JSStringRef sourceURL, int startingLineNumber, JSValueRef* exception)
+JSValueRef JSEvaluateScriptInternal(const JSLockHolder&, ExecState* exec, JSContextRef ctx, JSObjectRef thisObject, const SourceCode& source, JSValueRef* exception)
 {
-    if (!ctx) {
-        ASSERT_NOT_REACHED();
-        return 0;
-    }
-    ExecState* exec = toJS(ctx);
-    VM& vm = exec->vm();
-    JSLockHolder locker(vm);
+    UNUSED_PARAM(ctx);
 
     JSObject* jsThisObject = toJS(thisObject);
 
-    startingLineNumber = std::max(1, startingLineNumber);
-
     // evaluate sets "this" to the global object if it is NULL
+    VM& vm = exec->vm();
     JSGlobalObject* globalObject = vm.vmEntryGlobalObject(exec);
-    auto sourceURLString = sourceURL ? sourceURL->string() : String();
-    SourceCode source = makeSource(script->string(), SourceOrigin { sourceURLString }, URL({ }, sourceURLString), TextPosition(OrdinalNumber::fromOneBasedInt(startingLineNumber), OrdinalNumber()));
-
     NakedPtr<Exception> evaluationException;
     JSValue returnValue = profiledEvaluate(globalObject->globalExec(), ProfilingReason::API, source, jsThisObject, evaluationException);
 
@@ -80,7 +71,7 @@ JSValueRef JSEvaluateScript(JSContextRef ctx, JSStringRef script, JSObjectRef th
         // We could stash it in the inspector in case an inspector is ever opened.
         globalObject->inspectorController().reportAPIException(exec, evaluationException);
 #endif
-        return 0;
+        return nullptr;
     }
 
     if (returnValue)
@@ -90,6 +81,24 @@ JSValueRef JSEvaluateScript(JSContextRef ctx, JSStringRef script, JSObjectRef th
     return toRef(exec, jsUndefined());
 }
 
+JSValueRef JSEvaluateScript(JSContextRef ctx, JSStringRef script, JSObjectRef thisObject, JSStringRef sourceURL, int startingLineNumber, JSValueRef* exception)
+{
+    if (!ctx) {
+        ASSERT_NOT_REACHED();
+        return nullptr;
+    }
+    ExecState* exec = toJS(ctx);
+    VM& vm = exec->vm();
+    JSLockHolder locker(vm);
+
+    startingLineNumber = std::max(1, startingLineNumber);
+
+    auto sourceURLString = sourceURL ? sourceURL->string() : String();
+    SourceCode source = makeSource(script->string(), SourceOrigin { sourceURLString }, URL({ }, sourceURLString), TextPosition(OrdinalNumber::fromOneBasedInt(startingLineNumber), OrdinalNumber()));
+
+    return JSEvaluateScriptInternal(locker, exec, ctx, thisObject, source, exception);
+}
+
 bool JSCheckScriptSyntax(JSContextRef ctx, JSStringRef script, JSStringRef sourceURL, int startingLineNumber, JSValueRef* exception)
 {
     if (!ctx) {

Source/JavaScriptCore/API/JSBaseInternal.h

@@ -0,0 +1,36 @@
+/*
+ * Copyright (C) 2019 Apple Inc.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#pragma once
+
+#include <JavaScriptCore/JSBase.h>
+#include <JavaScriptCore/WebKitAvailability.h>
+
+namespace JSC {
+class JSLockHolder;
+class ExecState;
+}
+
+extern "C" JSValueRef JSEvaluateScriptInternal(const JSC::JSLockHolder&, JSC::ExecState*, JSContextRef, JSObjectRef thisObject, const JSC::SourceCode&, JSValueRef* exception);

Source/JavaScriptCore/API/JSContext.mm

@@ -27,6 +27,7 @@
 
 #import "APICast.h"
 #import "Completion.h"
+#import "JSBaseInternal.h"
 #import "JSCInlines.h"
 #import "JSContextInternal.h"
 #import "JSContextPrivate.h"
@@ -112,10 +113,38 @@ - (JSValue *)evaluateScript:(NSString *)script withSourceURL:(NSURL *)sourceURL
 
     if (exceptionValue)
         return [self valueFromNotifyException:exceptionValue];
-
     return [JSValue valueWithJSValueRef:result inContext:self];
 }
 
+- (JSValue *)evaluateJSScript:(JSScript *)script
+{
+    JSC::ExecState* exec = toJS(m_context);
+    JSC::VM& vm = exec->vm();
+    JSC::JSLockHolder locker(vm);
+
+    if (script.type == kJSScriptTypeProgram) {
+        JSValueRef exceptionValue = nullptr;
+        JSValueRef result = JSEvaluateScriptInternal(locker, exec, m_context, nullptr, [script jsSourceCode]->sourceCode(), &exceptionValue);
+
+        if (exceptionValue)
+            return [self valueFromNotifyException:exceptionValue];
+        return [JSValue valueWithJSValueRef:result inContext:self];
+    }
+
+    auto* globalObject = JSC::jsDynamicCast<JSC::JSAPIGlobalObject*>(vm, exec->lexicalGlobalObject());
+    if (!globalObject)
+        return [JSValue valueWithNewPromiseRejectedWithReason:[JSValue valueWithNewErrorFromMessage:@"Context does not support module loading" inContext:self] inContext:self];
+
+    auto scope = DECLARE_CATCH_SCOPE(vm);
+    JSC::JSValue result = globalObject->loadAndEvaluateJSScriptModule(locker, script);
+    if (scope.exception()) {
+        JSValueRef exceptionValue = toRef(exec, scope.exception()->value());
+        scope.clearException();
+        return [JSValue valueWithNewPromiseRejectedWithReason:[JSValue valueWithJSValueRef:exceptionValue inContext:self] inContext:self];
+    }
+    return [JSValue valueWithJSValueRef:toRef(vm, result) inContext:self];
+}
+
 - (void)setException:(JSValue *)value
 {
     JSC::ExecState* exec = toJS(m_context);

Source/JavaScriptCore/API/JSContextPrivate.h

@@ -74,6 +74,16 @@
 /*! @abstract The delegate the context will use when trying to load a module. Note, this delegate will be ignored for contexts returned by UIWebView. */
 @property (nonatomic, weak) id <JSModuleLoaderDelegate> moduleLoaderDelegate JSC_API_AVAILABLE(macosx(JSC_MAC_TBA), ios(JSC_IOS_TBA));
 
+/*!
+ @method
+ @abstract Run a JSScript.
+ @param script the JSScript to evaluate.
+ @discussion If the provided JSScript was created with kJSScriptTypeProgram, the script will run synchronously and return the result of evaluation.
+
+ Otherwise, if the script was created with kJSScriptTypeModule, the module will be run asynchronously and will return a promise resolved when the module and any transitive dependencies are loaded. The module loader will treat the script as if it had been returned from a delegate call to moduleLoaderDelegate. This mirrors the JavaScript dynamic import operation.
+ */
+- (JSValue *)evaluateJSScript:(JSScript *)script;
+
 @end
 
 #endif

Source/JavaScriptCore/API/JSScript.h

@@ -31,37 +31,84 @@ NS_ASSUME_NONNULL_BEGIN
 
 @class JSVirtualMachine;
 
+/*!
+ @enum JSScriptType
+ @abstract     A constant identifying the execution type of a JSScript.
+ @constant     kJSScriptTypeProgram  The type of a normal JavaScript program.
+ @constant     kJSScriptTypeModule   The type of a module JavaScript program.
+ */
+typedef NS_ENUM(NSInteger, JSScriptType) {
+    kJSScriptTypeProgram,
+    kJSScriptTypeModule,
+};
+
+
 JSC_CLASS_AVAILABLE(macosx(JSC_MAC_TBA), ios(JSC_IOS_TBA))
 @interface JSScript : NSObject
 
+/*!
+ This SPI is deprecated and should not be used. Use "scriptOfType:withSource:andSourceURL:andBytecodeCache:inVirtualMachine:error:" instead.
+ */
++ (nullable instancetype)scriptWithSource:(NSString *)source inVirtualMachine:(JSVirtualMachine *)vm JSC_API_DEPRECATED("Use +scriptOfType:withSource:andSourceURL:andBytecodeCache:inVirtualMachine:error: instead.", macosx(JSC_MAC_TBA, JSC_MAC_TBA), ios(JSC_IOS_TBA, JSC_IOS_TBA));
+
+/*!
+ This SPI is deprecated and should not be used. Use "scriptOfType:memoryMappedFromASCIIFile:withSourceURL:andBytecodeCache:inVirtualMachine:error:" instead.
+ */
++ (nullable instancetype)scriptFromASCIIFile:(NSURL *)filePath inVirtualMachine:(JSVirtualMachine *)vm withCodeSigning:(nullable NSURL *)codeSigningPath andBytecodeCache:(nullable NSURL *)cachePath JSC_API_DEPRECATED("Use +scriptOfType:memoryMappedFromASCIIFile:withSourceURL:andBytecodeCache:inVirtualMachine:error: instead.", macosx(JSC_MAC_TBA, JSC_MAC_TBA), ios(JSC_IOS_TBA, JSC_IOS_TBA));
+
+/*!
+ This API is deprecated and should not be used.
+ */
++ (nullable instancetype)scriptFromUTF8File:(NSURL *)filePath inVirtualMachine:(JSVirtualMachine *)vm withCodeSigning:(nullable NSURL *)codeSigningPath andBytecodeCache:(nullable NSURL *)cachePath JSC_API_DEPRECATED("Do not use this. Use +scriptOfType:memoryMappedFromASCIIFile:withSourceURL:andBytecodeCache:inVirtualMachine:error: or +scriptOfType:withSource:andSourceURL:andBytecodeCache:inVirtualMachine:error: instead", macosx(JSC_MAC_TBA, JSC_MAC_TBA), ios(JSC_IOS_TBA, JSC_IOS_TBA));
+
 /*!
  @method
  @abstract Create a JSScript for the specified virtual machine.
+ @param type The type of JavaScript source.
  @param source The source code to use when the script is evaluated by the JS vm.
+ @param sourceURL The source URL to associate with this script. For modules, this is the module identifier.
+ @param cachePath A URL containing the path where the VM should cache for future execution. On creation, we use this path to load the cached bytecode off disk. If the cached bytecode at this location is stale, you should delete that file before calling this constructor.
  @param vm The JSVirtualMachine the script can be evaluated in.
+ @param error A description of why the script could not be created if the result is nil.
  @result The new script.
+ @discussion The file at cachePath should not be externally modified for the lifecycle of vm.
  */
-+ (nullable instancetype)scriptWithSource:(NSString *)source inVirtualMachine:(JSVirtualMachine *)vm;
++ (nullable instancetype)scriptOfType:(JSScriptType)type withSource:(NSString *)source andSourceURL:(NSURL *)sourceURL andBytecodeCache:(nullable NSURL *)cachePath inVirtualMachine:(JSVirtualMachine *)vm error:(out NSError * _Nullable * _Nullable)error;
 
 /*!
  @method
  @abstract Create a JSScript for the specified virtual machine with a path to a codesigning and bytecode caching.
+ @param type The type of JavaScript source.
  @param filePath A URL containing the path to a JS source code file on disk.
+ @param sourceURL The source URL to associate with this script. For modules, this is the module identifier.
+ @param cachePath A URL containing the path where the VM should cache for future execution. On creation, we use this path to load the cached bytecode off disk. If the cached bytecode at this location is stale, you should delete that file before calling this constructor.
  @param vm The JSVirtualMachine the script can be evaluated in.
- @param codeSigningPath A URL containing the path to the codeSigning file for filePath on disk.
- @param cachePath A URL containing the path where the VM should cache for future execution.
+ @param error A description of why the script could not be created if the result is nil.
  @result The new script.
- @discussion the files at filePath, codeSigningPath, and cachePath should not be externally modified  for the lifecycle of vm. Note that codeSigningPath and cachePath are not used currently, but that will change in the near future.
+ @discussion The files at filePath and cachePath should not be externally modified for the lifecycle of vm. This method will file back the memory for the source.
 
  If the file at filePath is not ascii this method will return nil.
  */
-+ (nullable instancetype)scriptFromASCIIFile:(NSURL *)filePath inVirtualMachine:(JSVirtualMachine *)vm withCodeSigning:(nullable NSURL *)codeSigningPath andBytecodeCache:(nullable NSURL *)cachePath;
++ (nullable instancetype)scriptOfType:(JSScriptType)type memoryMappedFromASCIIFile:(NSURL *)filePath withSourceURL:(NSURL *)sourceURL andBytecodeCache:(nullable NSURL *)cachePath inVirtualMachine:(JSVirtualMachine *)vm error:(out NSError * _Nullable * _Nullable)error;
+
+/*!
+ @method
+ @abstract Cache the bytecode for this JSScript to disk at the path passed in during creation.
+ @param error A description of why the script could not be cached if the result is FALSE.
+ */
+- (BOOL)cacheBytecodeWithError:(out NSError * _Nullable * _Nullable)error;
 
+/*!
+ @method
+ @abstract Returns the JSScriptType of this JSScript.
+ */
+- (JSScriptType)type;
 
 /*!
- This is deprecated and is equivalent to scriptFromASCIIFile:inVirtualMachine:withCodeSigning:andBytecodeCache:.
+ @method
+ @abstract Returns the sourceURL of this JSScript.
  */
-+ (nullable instancetype)scriptFromUTF8File:(NSURL *)filePath inVirtualMachine:(JSVirtualMachine *)vm withCodeSigning:(nullable NSURL *)codeSigningPath andBytecodeCache:(nullable NSURL *)cachePath;
+- (NSURL *)sourceURL;
 
 @end