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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
var EXPORTED_SYMBOLS = ["HandlerService"];
const { AppConstants } = ChromeUtils.import(
);
const { XPCOMUtils } = ChromeUtils.importESModule(
);
const {
saveToDisk,
alwaysAsk,
useHelperApp,
handleInternally,
useSystemDefault,
} = Ci.nsIHandlerInfo;
const TOPIC_PDFJS_HANDLER_CHANGED = "pdfjs:handlerChanged";
const lazy = {};
ChromeUtils.defineESModuleGetters(lazy, {
});
const { Integration } = ChromeUtils.importESModule(
);
Integration.downloads.defineModuleGetter(
lazy,
"DownloadIntegration",
);
XPCOMUtils.defineLazyServiceGetter(
lazy,
"externalProtocolService",
"@mozilla.org/uriloader/external-protocol-service;1",
"nsIExternalProtocolService"
);
XPCOMUtils.defineLazyServiceGetter(
lazy,
"MIMEService",
"@mozilla.org/mime;1",
"nsIMIMEService"
);
XPCOMUtils.defineLazyModuleGetters(lazy, {
});
function HandlerService() {
// Observe handlersvc-json-replace so we can switch to the datasource
Services.obs.addObserver(this, "handlersvc-json-replace", true);
}
HandlerService.prototype = {
QueryInterface: ChromeUtils.generateQI([
"nsISupportsWeakReference",
"nsIHandlerService",
"nsIObserver",
]),
__store: null,
get _store() {
if (!this.__store) {
this.__store = new lazy.JSONFile({
path: PathUtils.join(
Services.dirsvc.get("ProfD", Ci.nsIFile).path,
"handlers.json"
),
dataPostProcessor: this._dataPostProcessor.bind(this),
});
}
// Always call this even if this.__store was set, since it may have been
// set by asyncInit, which might not have completed yet.
this._ensureStoreInitialized();
return this.__store;
},
__storeInitialized: false,
_ensureStoreInitialized() {
if (!this.__storeInitialized) {
this.__storeInitialized = true;
this.__store.ensureDataReady();
this._injectDefaultProtocolHandlersIfNeeded();
this._migrateProtocolHandlersIfNeeded();
Services.obs.notifyObservers(null, "handlersvc-store-initialized");
// Bug 1736924: run migration for browser.download.improvements_to_download_panel if applicable.
// Since we need DownloadsViewInternally to verify mimetypes, we run this after
// DownloadsViewInternally is registered via the 'handlersvc-store-initialized' notification.
this._migrateDownloadsImprovementsIfNeeded();
this._migrateSVGXMLIfNeeded();
}
},
_dataPostProcessor(data) {
return data.defaultHandlersVersion
? data
: {
defaultHandlersVersion: {},
mimeTypes: {},
schemes: {},
isDownloadsImprovementsAlreadyMigrated: false,
};
},
/**
* Injects new default protocol handlers if the version in the preferences is
* newer than the one in the data store.
*/
_injectDefaultProtocolHandlersIfNeeded() {
try {
let defaultHandlersVersion = Services.prefs.getIntPref(
"gecko.handlerService.defaultHandlersVersion",
0
);
if (defaultHandlersVersion < lazy.kHandlerListVersion) {
this._injectDefaultProtocolHandlers();
Services.prefs.setIntPref(
"gecko.handlerService.defaultHandlersVersion",
lazy.kHandlerListVersion
);
// Now save the result:
this._store.saveSoon();
}
} catch (ex) {
Cu.reportError(ex);
}
},
_injectDefaultProtocolHandlers() {
let locale = Services.locale.appLocaleAsBCP47;
// Initialize handlers to default and update based on locale.
let localeHandlers = lazy.kHandlerList.default;
if (lazy.kHandlerList[locale]) {
for (let scheme in lazy.kHandlerList[locale].schemes) {
localeHandlers.schemes[scheme] =
lazy.kHandlerList[locale].schemes[scheme];
}
}
// Now, we're going to cheat. Terribly. The idiologically correct way
// of implementing the following bit of code would be to fetch the
// handler info objects from the protocol service, manipulate those,
// and then store each of them.
// However, that's expensive. It causes us to talk to the OS about
// default apps, which causes the OS to go hit the disk.
// All we're trying to do is insert some web apps into the list. We
// don't care what's already in the file, we just want to do the
// equivalent of appending into the database. So let's just go do that:
for (let scheme of Object.keys(localeHandlers.schemes)) {
if (scheme == "mailto" && AppConstants.MOZ_APP_NAME == "thunderbird") {
// Thunderbird IS a mailto handler, it doesn't need handlers added.
continue;
}
let existingSchemeInfo = this._store.data.schemes[scheme];
if (!existingSchemeInfo) {
// Haven't seen this scheme before. Default to asking which app the
// user wants to use:
existingSchemeInfo = {
// Signal to future readers that we didn't ask the OS anything.
// When the entry is first used, get the info from the OS.
stubEntry: true,
// The first item in the list is the preferred handler, and
// there isn't one, so we fill in null:
handlers: [null],
};
this._store.data.schemes[scheme] = existingSchemeInfo;
}
let { handlers } = existingSchemeInfo;
for (let newHandler of localeHandlers.schemes[scheme].handlers) {
// If there is already a handler registered with the same template
// URL, ignore the new one:
let matchingTemplate = handler =>
handler && handler.uriTemplate == newHandler.uriTemplate;
if (!handlers.some(matchingTemplate)) {
handlers.push(newHandler);
}
}
}
},
/**
* Execute any migrations. Migrations are defined here for any changes or removals for
* existing handlers. Additions are still handled via the localized prefs infrastructure.
*
* This depends on the browser.handlers.migrations pref being set by migrateUI in
* nsBrowserGlue (for Fx Desktop) or similar mechanisms for other products.
* This is a comma-separated list of identifiers of migrations that need running.
* This avoids both re-running older migrations and keeping an additional
* pref around permanently.
*/
_migrateProtocolHandlersIfNeeded() {
const kMigrations = {
"30boxes": () => {
const k30BoxesRegex = /^https?:\/\/(?:www\.)?30boxes.com\/external\/widget/i;
let webcalHandler = lazy.externalProtocolService.getProtocolHandlerInfo(
"webcal"
);
if (this.exists(webcalHandler)) {
this.fillHandlerInfo(webcalHandler, "");
let shouldStore = false;
// First remove 30boxes from possible handlers.
let handlers = webcalHandler.possibleApplicationHandlers;
for (let i = handlers.length - 1; i >= 0; i--) {
let app = handlers.queryElementAt(i, Ci.nsIHandlerApp);
if (
app instanceof Ci.nsIWebHandlerApp &&
k30BoxesRegex.test(app.uriTemplate)
) {
shouldStore = true;
handlers.removeElementAt(i);
}
}
// Then remove as a preferred handler.
if (webcalHandler.preferredApplicationHandler) {
let app = webcalHandler.preferredApplicationHandler;
if (
app instanceof Ci.nsIWebHandlerApp &&
k30BoxesRegex.test(app.uriTemplate)
) {
webcalHandler.preferredApplicationHandler = null;
shouldStore = true;
}
}
// Then store, if we changed anything.
if (shouldStore) {
this.store(webcalHandler);
}
}
},
"secure-mail": () => {
const kSubstitutions = new Map([
[
],
[
],
[
],
[
],
]);
function maybeReplaceURL(app) {
if (app instanceof Ci.nsIWebHandlerApp) {
let { uriTemplate } = app;
let sub = kSubstitutions.get(uriTemplate);
if (sub) {
app.uriTemplate = sub;
return true;
}
}
return false;
}
let mailHandler = lazy.externalProtocolService.getProtocolHandlerInfo(
"mailto"
);
if (this.exists(mailHandler)) {
this.fillHandlerInfo(mailHandler, "");
let handlers = mailHandler.possibleApplicationHandlers;
let shouldStore = false;
for (let i = handlers.length - 1; i >= 0; i--) {
let app = handlers.queryElementAt(i, Ci.nsIHandlerApp);
// Note: will evaluate the RHS because it's a binary rather than
// logical or.
shouldStore |= maybeReplaceURL(app);
}
// Then check the preferred handler.
if (mailHandler.preferredApplicationHandler) {
shouldStore |= maybeReplaceURL(
mailHandler.preferredApplicationHandler
);
}
// Then store, if we changed anything. Note that store() handles
// duplicates, so we don't have to.
if (shouldStore) {
this.store(mailHandler);
}
}
},
};
let migrationsToRun = Services.prefs.getCharPref(
"browser.handlers.migrations",
""
);
migrationsToRun = migrationsToRun ? migrationsToRun.split(",") : [];
for (let migration of migrationsToRun) {
migration.trim();
try {
kMigrations[migration]();
} catch (ex) {
Cu.reportError(ex);
}
}
if (migrationsToRun.length) {
Services.prefs.clearUserPref("browser.handlers.migrations");
}
},
_onDBChange() {
return (async () => {
if (this.__store) {
await this.__store.finalize();
}
this.__store = null;
this.__storeInitialized = false;
})().catch(Cu.reportError);
},
// nsIObserver
observe(subject, topic, data) {
if (topic != "handlersvc-json-replace") {
return;
}
let promise = this._onDBChange();
promise.then(() => {
Services.obs.notifyObservers(null, "handlersvc-json-replace-complete");
});
},
// nsIHandlerService
asyncInit() {
if (!this.__store) {
this.__store = new lazy.JSONFile({
path: PathUtils.join(
Services.dirsvc.get("ProfD", Ci.nsIFile).path,
"handlers.json"
),
dataPostProcessor: this._dataPostProcessor.bind(this),
});
this.__store
.load()
.then(() => {
// __store can be null if we called _onDBChange in the mean time.
if (this.__store) {
this._ensureStoreInitialized();
}
})
.catch(Cu.reportError);
}
},
/**
* Update already existing handlers for non-internal mimetypes to have prefs set from alwaysAsk
* to saveToDisk. However, if reading an internal mimetype and set to alwaysAsk, update to use handleInternally.
* This migration is needed since browser.download.improvements_to_download_panel does not
* override user preferences if preferredAction = alwaysAsk. By doing so, we can ensure that file prompt
* behaviours remain consistent for most files.
*
* See Bug 1736924 for more information.
*/
_noInternalHandlingDefault: new Set([
"text/xml",
"application/xml",
"image/svg+xml",
]),
_migrateDownloadsImprovementsIfNeeded() {
// Migrate if the preference is enabled AND if the migration has never been run before.
// Otherwise, we risk overwriting preferences for existing profiles!
if (
Services.prefs.getBoolPref(
"browser.download.improvements_to_download_panel"
) &&
!Services.policies.getActivePolicies()?.Handlers &&
!this._store.data.isDownloadsImprovementsAlreadyMigrated &&
AppConstants.MOZ_APP_NAME != "thunderbird"
) {
for (let [type, mimeInfo] of Object.entries(this._store.data.mimeTypes)) {
let isViewableInternally =
lazy.DownloadIntegration.shouldViewDownloadInternally(type) &&
!this._noInternalHandlingDefault.has(type);
let isAskOnly = mimeInfo && mimeInfo.ask;
if (isAskOnly) {
if (isViewableInternally) {
mimeInfo.action = handleInternally;
} else {
mimeInfo.action = saveToDisk;
}
// Sets alwaysAskBeforeHandling to false. Needed to ensure that:
// preferredAction appears as expected in preferences table; and
// downloads behaviour is updated to never show UCT window.
mimeInfo.ask = false;
}
}
this._store.data.isDownloadsImprovementsAlreadyMigrated = true;
this._store.saveSoon();
}
},
_migrateSVGXMLIfNeeded() {
// Migrate if the preference is enabled AND if the migration has never been run before.
// We need to make sure we only run this once.
if (
Services.prefs.getBoolPref(
"browser.download.improvements_to_download_panel"
) &&
!Services.policies.getActivePolicies()?.Handlers &&
!this._store.data.isSVGXMLAlreadyMigrated
) {
for (let type of this._noInternalHandlingDefault) {
if (Object.hasOwn(this._store.data.mimeTypes, type)) {
let mimeInfo = this._store.data.mimeTypes[type];
if (!mimeInfo.ask && mimeInfo.action == handleInternally) {
mimeInfo.action = saveToDisk;
}
}
}
this._store.data.isSVGXMLAlreadyMigrated = true;
this._store.saveSoon();
}
},
// nsIHandlerService
enumerate() {
let handlers = Cc["@mozilla.org/array;1"].createInstance(
Ci.nsIMutableArray
);
for (let [type, typeInfo] of Object.entries(this._store.data.mimeTypes)) {
let primaryExtension = typeInfo.extensions?.[0] ?? null;
let handler = lazy.MIMEService.getFromTypeAndExtension(
type,
primaryExtension
);
handlers.appendElement(handler);
}
for (let type of Object.keys(this._store.data.schemes)) {
// nsIExternalProtocolService.getProtocolHandlerInfo can be expensive
// on Windows, so we return a proxy to delay retrieving the nsIHandlerInfo
// until one of its properties is accessed.
//
// Note: our caller still needs to yield periodically when iterating
// the enumerator and accessing handler properties to avoid monopolizing
// the main thread.
//
let handler = new Proxy(
{
QueryInterface: ChromeUtils.generateQI(["nsIHandlerInfo"]),
type,
get _handlerInfo() {
delete this._handlerInfo;
return (this._handlerInfo = lazy.externalProtocolService.getProtocolHandlerInfo(
type
));
},
},
{
get(target, name) {
return target[name] || target._handlerInfo[name];
},
set(target, name, value) {
target._handlerInfo[name] = value;
},
}
);
handlers.appendElement(handler);
}
return handlers.enumerate(Ci.nsIHandlerInfo);
},
// nsIHandlerService
store(handlerInfo) {
let handlerList = this._getHandlerListByHandlerInfoType(handlerInfo);
// Retrieve an existing entry if present, instead of creating a new one, so
// that we preserve unknown properties for forward compatibility.
let storedHandlerInfo = handlerList[handlerInfo.type];
if (!storedHandlerInfo) {
storedHandlerInfo = {};
handlerList[handlerInfo.type] = storedHandlerInfo;
}
// Only a limited number of preferredAction values is allowed.
if (
handlerInfo.preferredAction == saveToDisk ||
handlerInfo.preferredAction == useSystemDefault ||
handlerInfo.preferredAction == handleInternally ||
// For files (ie mimetype rather than protocol handling info), ensure
// we can store the "always ask" state, too:
(handlerInfo.preferredAction == alwaysAsk &&
this._isMIMEInfo(handlerInfo) &&
Services.prefs.getBoolPref(
"browser.download.improvements_to_download_panel"
))
) {
storedHandlerInfo.action = handlerInfo.preferredAction;
} else {
storedHandlerInfo.action = useHelperApp;
}
if (handlerInfo.alwaysAskBeforeHandling) {
storedHandlerInfo.ask = true;
} else {
delete storedHandlerInfo.ask;
}
// Build a list of unique nsIHandlerInfo instances to process later.
let handlers = [];
if (handlerInfo.preferredApplicationHandler) {
handlers.push(handlerInfo.preferredApplicationHandler);
}
for (let handler of handlerInfo.possibleApplicationHandlers.enumerate(
Ci.nsIHandlerApp
)) {
// If the caller stored duplicate handlers, we save them only once.
if (!handlers.some(h => h.equals(handler))) {
handlers.push(handler);
}
}
// If any of the nsIHandlerInfo instances cannot be serialized, it is not
// included in the final list. The first element is always the preferred
// handler, or null if there is none.
let serializableHandlers = handlers
.map(h => this.handlerAppToSerializable(h))
.filter(h => h);
if (serializableHandlers.length) {
if (!handlerInfo.preferredApplicationHandler) {
serializableHandlers.unshift(null);
}
storedHandlerInfo.handlers = serializableHandlers;
} else {
delete storedHandlerInfo.handlers;
}
if (this._isMIMEInfo(handlerInfo)) {
let extensions = storedHandlerInfo.extensions || [];
for (let extension of handlerInfo.getFileExtensions()) {
extension = extension.toLowerCase();
// If the caller stored duplicate extensions, we save them only once.
if (!extensions.includes(extension)) {
extensions.push(extension);
}
}
if (extensions.length) {
storedHandlerInfo.extensions = extensions;
} else {
delete storedHandlerInfo.extensions;
}
}
// If we're saving *anything*, it stops being a stub:
delete storedHandlerInfo.stubEntry;
this._store.saveSoon();
// Now notify PDF.js. This is hacky, but a lot better than expecting all
// the consumers to do it...
if (handlerInfo.type == "application/pdf") {
Services.obs.notifyObservers(null, TOPIC_PDFJS_HANDLER_CHANGED);
}
},
// nsIHandlerService
fillHandlerInfo(handlerInfo, overrideType) {
let type = overrideType || handlerInfo.type;
let storedHandlerInfo = this._getHandlerListByHandlerInfoType(handlerInfo)[
type
];
if (!storedHandlerInfo) {
throw new Components.Exception(
"handlerSvc fillHandlerInfo: don't know this type",
Cr.NS_ERROR_NOT_AVAILABLE
);
}
let isStub = !!storedHandlerInfo.stubEntry;
// In the normal case, this is not a stub, so we can just read stored info
// and write to the handlerInfo object we were passed.
if (!isStub) {
handlerInfo.preferredAction = storedHandlerInfo.action;
handlerInfo.alwaysAskBeforeHandling = !!storedHandlerInfo.ask;
} else {
// If we've got a stub, ensure the defaults are still set:
lazy.externalProtocolService.setProtocolHandlerDefaults(
handlerInfo,
handlerInfo.hasDefaultHandler
);
if (
handlerInfo.preferredAction == alwaysAsk &&
handlerInfo.alwaysAskBeforeHandling
) {
// `store` will default to `useHelperApp` because `alwaysAsk` is
// not one of the 3 recognized options; for compatibility, do
// the same here.
handlerInfo.preferredAction = useHelperApp;
}
}
// If it *is* a stub, don't override alwaysAskBeforeHandling or the
// preferred actions. Instead, just append the stored handlers, without
// overriding the preferred app, and then schedule a task to store proper
// info for this handler.
this._appendStoredHandlers(handlerInfo, storedHandlerInfo.handlers, isStub);
if (this._isMIMEInfo(handlerInfo) && storedHandlerInfo.extensions) {
for (let extension of storedHandlerInfo.extensions) {
handlerInfo.appendExtension(extension);
}
} else if (this._mockedHandler) {
this._insertMockedHandler(handlerInfo);
}
},
/**
* Private method to inject stored handler information into an nsIHandlerInfo
* instance.
* @param handlerInfo the nsIHandlerInfo instance to write to
* @param storedHandlers the stored handlers
* @param keepPreferredApp whether to keep the handlerInfo's
* preferredApplicationHandler or override it
* (default: false, ie override it)
*/
_appendStoredHandlers(handlerInfo, storedHandlers, keepPreferredApp) {
// If the first item is not null, it is also the preferred handler. Since
// we cannot modify the stored array, use a boolean to keep track of this.
let isFirstItem = true;
for (let handler of storedHandlers || [null]) {
let handlerApp = this.handlerAppFromSerializable(handler || {});
if (isFirstItem) {
isFirstItem = false;
// Do not overwrite the preferred app unless that's allowed
if (!keepPreferredApp) {
handlerInfo.preferredApplicationHandler = handlerApp;
}
}
if (handlerApp) {
handlerInfo.possibleApplicationHandlers.appendElement(handlerApp);
}
}
},
/**
* @param handler
* A nsIHandlerApp handler app
* @returns Serializable representation of a handler app object.
*/
handlerAppToSerializable(handler) {
if (handler instanceof Ci.nsILocalHandlerApp) {
return {
name: handler.name,
path: handler.executable.path,
};
} else if (handler instanceof Ci.nsIWebHandlerApp) {
return {
name: handler.name,
uriTemplate: handler.uriTemplate,
};
} else if (handler instanceof Ci.nsIDBusHandlerApp) {
return {
name: handler.name,
service: handler.service,
method: handler.method,
objectPath: handler.objectPath,
dBusInterface: handler.dBusInterface,
};
} else if (handler instanceof Ci.nsIGIOMimeApp) {
return {
name: handler.name,
command: handler.command,
};
}
// If the handler is an unknown handler type, return null.
// Android default application handler is the case.
return null;
},
/**
* @param handlerObj
* Serializable representation of a handler object.
* @returns {nsIHandlerApp} the handler app, if any; otherwise null
*/
handlerAppFromSerializable(handlerObj) {
let handlerApp;
if ("path" in handlerObj) {
try {
let file = new lazy.FileUtils.File(handlerObj.path);
if (!file.exists()) {
return null;
}
handlerApp = Cc[
"@mozilla.org/uriloader/local-handler-app;1"
].createInstance(Ci.nsILocalHandlerApp);
handlerApp.executable = file;
} catch (ex) {
return null;
}
} else if ("uriTemplate" in handlerObj) {
handlerApp = Cc[
"@mozilla.org/uriloader/web-handler-app;1"
].createInstance(Ci.nsIWebHandlerApp);
handlerApp.uriTemplate = handlerObj.uriTemplate;
} else if ("service" in handlerObj) {
handlerApp = Cc[
"@mozilla.org/uriloader/dbus-handler-app;1"
].createInstance(Ci.nsIDBusHandlerApp);
handlerApp.service = handlerObj.service;
handlerApp.method = handlerObj.method;
handlerApp.objectPath = handlerObj.objectPath;
handlerApp.dBusInterface = handlerObj.dBusInterface;
} else if ("command" in handlerObj && "@mozilla.org/gio-service;1" in Cc) {
try {
handlerApp = Cc["@mozilla.org/gio-service;1"]
.getService(Ci.nsIGIOService)
.createAppFromCommand(handlerObj.command, handlerObj.name);
} catch (ex) {
return null;
}
} else {
return null;
}
handlerApp.name = handlerObj.name;
return handlerApp;
},
/**
* The function returns a reference to the "mimeTypes" or "schemes" object
* based on which type of handlerInfo is provided.
*/
_getHandlerListByHandlerInfoType(handlerInfo) {
return this._isMIMEInfo(handlerInfo)
? this._store.data.mimeTypes
: this._store.data.schemes;
},
/**
* Determines whether an nsIHandlerInfo instance represents a MIME type.
*/
_isMIMEInfo(handlerInfo) {
// We cannot rely only on the instanceof check because on Android both MIME
// types and protocols are instances of nsIMIMEInfo. We still do the check
// so that properties of nsIMIMEInfo become available to the callers.
return (
handlerInfo instanceof Ci.nsIMIMEInfo && handlerInfo.type.includes("/")
);
},
// nsIHandlerService
exists(handlerInfo) {
return (
handlerInfo.type in this._getHandlerListByHandlerInfoType(handlerInfo)
);
},
// nsIHandlerService
remove(handlerInfo) {
delete this._getHandlerListByHandlerInfoType(handlerInfo)[handlerInfo.type];
this._store.saveSoon();
},
// nsIHandlerService
getTypeFromExtension(fileExtension) {
let extension = fileExtension.toLowerCase();
let mimeTypes = this._store.data.mimeTypes;
for (let type of Object.keys(mimeTypes)) {
if (
mimeTypes[type].extensions &&
mimeTypes[type].extensions.includes(extension)
) {
return type;
}
}
return "";
},
_mockedHandler: null,
_mockedProtocol: null,
_insertMockedHandler(handlerInfo) {
if (handlerInfo.type == this._mockedProtocol) {
handlerInfo.preferredApplicationHandler = this._mockedHandler;
handlerInfo.possibleApplicationHandlers.insertElementAt(
this._mockedHandler,
0
);
}
},
// test-only: mock the handler instance for a particular protocol/scheme
mockProtocolHandler(protocol) {
if (!protocol) {
this._mockedProtocol = null;
this._mockedHandler = null;
return;
}
this._mockedProtocol = protocol;
this._mockedHandler = {
QueryInterface: ChromeUtils.generateQI([Ci.nsILocalHandlerApp]),
launchWithURI(uri, context) {
Services.obs.notifyObservers(uri, "mocked-protocol-handler");
},
name: "Mocked handler",
detailedDescription: "Mocked handler for tests",
equals(x) {
return x == this;
},
get executable() {
if (AppConstants.platform == "macosx") {
// We need an app path that isn't us, nor in our app bundle, and
// Apple no longer allows us to read the default-shipped apps
// in /Applications/ - except for Safari, it would appear!
let f = Cc["@mozilla.org/file/local;1"].createInstance(Ci.nsIFile);
f.initWithPath("/Applications/Safari.app");
return f;
}
return Services.dirsvc.get("XCurProcD", Ci.nsIFile);
},
parameterCount: 0,
clearParameters() {},
appendParameter() {},
getParameter() {},
parameterExists() {
return false;
},
};
},
};