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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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
#include "GeckoProfiler.h"
#include "LoadedScript.h"
#include "ModuleLoadRequest.h"
#include "ScriptLoadRequest.h"
#include "mozilla/dom/ScriptSettings.h" // AutoJSAPI
#include "mozilla/dom/ScriptTrace.h"
#include "js/Array.h" // JS::GetArrayLength
#include "js/CompilationAndEvaluation.h"
#include "js/ColumnNumber.h" // JS::ColumnNumberOneOrigin
#include "js/ContextOptions.h" // JS::ContextOptionsRef
#include "js/ErrorReport.h" // JSErrorBase
#include "js/friend/ErrorMessages.h" // js::GetErrorMessage, JSMSG_*
#include "js/Modules.h" // JS::FinishDynamicModuleImport, JS::{G,S}etModuleResolveHook, JS::Get{ModulePrivate,ModuleScript,RequestedModule{s,Specifier,SourcePos}}, JS::SetModule{DynamicImport,Metadata}Hook
#include "js/PropertyAndElement.h" // JS_DefineProperty, JS_GetElement
#include "js/SourceText.h"
#include "mozilla/Assertions.h" // MOZ_ASSERT
#include "mozilla/BasePrincipal.h"
#include "mozilla/dom/AutoEntryScript.h"
#include "mozilla/dom/ScriptLoadContext.h"
#include "mozilla/CycleCollectedJSContext.h" // nsAutoMicroTask
#include "mozilla/Preferences.h"
#include "mozilla/RefPtr.h" // mozilla::StaticRefPtr
#include "mozilla/StaticPrefs_dom.h"
#include "nsContentUtils.h"
#include "nsICacheInfoChannel.h" // nsICacheInfoChannel
#include "nsNetUtil.h" // NS_NewURI
#include "xpcpublic.h"
using mozilla::CycleCollectedJSContext;
using mozilla::Err;
using mozilla::Preferences;
using mozilla::UniquePtr;
using mozilla::WrapNotNull;
using mozilla::dom::AutoJSAPI;
namespace JS::loader {
mozilla::LazyLogModule ModuleLoaderBase::gCspPRLog("CSP");
mozilla::LazyLogModule ModuleLoaderBase::gModuleLoaderBaseLog(
"ModuleLoaderBase");
#undef LOG
#define LOG(args) \
MOZ_LOG(ModuleLoaderBase::gModuleLoaderBaseLog, mozilla::LogLevel::Debug, \
args)
#define LOG_ENABLED() \
MOZ_LOG_TEST(ModuleLoaderBase::gModuleLoaderBaseLog, mozilla::LogLevel::Debug)
//////////////////////////////////////////////////////////////
// ModuleLoaderBase::LoadingRequest
//////////////////////////////////////////////////////////////
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ModuleLoaderBase::LoadingRequest)
NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTION(ModuleLoaderBase::LoadingRequest, mRequest, mWaiting)
NS_IMPL_CYCLE_COLLECTING_ADDREF(ModuleLoaderBase::LoadingRequest)
NS_IMPL_CYCLE_COLLECTING_RELEASE(ModuleLoaderBase::LoadingRequest)
//////////////////////////////////////////////////////////////
// ModuleLoaderBase
//////////////////////////////////////////////////////////////
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ModuleLoaderBase)
NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTION(ModuleLoaderBase, mFetchingModules, mFetchedModules,
mDynamicImportRequests, mGlobalObject, mLoader)
NS_IMPL_CYCLE_COLLECTING_ADDREF(ModuleLoaderBase)
NS_IMPL_CYCLE_COLLECTING_RELEASE(ModuleLoaderBase)
// static
void ModuleLoaderBase::EnsureModuleHooksInitialized() {
AutoJSAPI jsapi;
jsapi.Init();
JSRuntime* rt = JS_GetRuntime(jsapi.cx());
if (JS::GetModuleResolveHook(rt)) {
return;
}
JS::SetModuleResolveHook(rt, HostResolveImportedModule);
JS::SetModuleMetadataHook(rt, HostPopulateImportMeta);
JS::SetScriptPrivateReferenceHooks(rt, HostAddRefTopLevelScript,
HostReleaseTopLevelScript);
JS::SetModuleDynamicImportHook(rt, HostImportModuleDynamically);
}
// 8.1.3.8.1 HostResolveImportedModule(referencingModule, moduleRequest)
/**
* Implement the HostResolveImportedModule abstract operation.
*
* Resolve a module specifier string and look this up in the module
* map, returning the result. This is only called for previously
* loaded modules and always succeeds.
*
* @param aReferencingPrivate A JS::Value which is either undefined
* or contains a LoadedScript private pointer.
* @param aModuleRequest A module request object.
* @returns module This is set to the module found.
*/
// static
JSObject* ModuleLoaderBase::HostResolveImportedModule(
JSContext* aCx, JS::Handle<JS::Value> aReferencingPrivate,
JS::Handle<JSObject*> aModuleRequest) {
JS::Rooted<JSObject*> module(aCx);
{
// LoadedScript should only live in this block, otherwise it will be a GC
// hazard
RefPtr<LoadedScript> script(
GetLoadedScriptOrNull(aCx, aReferencingPrivate));
JS::Rooted<JSString*> specifierString(
aCx, JS::GetModuleRequestSpecifier(aCx, aModuleRequest));
if (!specifierString) {
return nullptr;
}
// Let url be the result of resolving a module specifier given referencing
// module script and specifier.
nsAutoJSString string;
if (!string.init(aCx, specifierString)) {
return nullptr;
}
RefPtr<ModuleLoaderBase> loader = GetCurrentModuleLoader(aCx);
if (!loader) {
return nullptr;
}
auto result = loader->ResolveModuleSpecifier(script, string);
// This cannot fail because resolving a module specifier must have been
// previously successful with these same two arguments.
MOZ_ASSERT(result.isOk());
nsCOMPtr<nsIURI> uri = result.unwrap();
MOZ_ASSERT(uri, "Failed to resolve previously-resolved module specifier");
// Let resolved module script be moduleMap[url]. (This entry must exist for
// us to have gotten to this point.)
ModuleScript* ms = loader->GetFetchedModule(uri);
MOZ_ASSERT(ms, "Resolved module not found in module map");
MOZ_ASSERT(!ms->HasParseError());
MOZ_ASSERT(ms->ModuleRecord());
module.set(ms->ModuleRecord());
}
return module;
}
// static
bool ModuleLoaderBase::ImportMetaResolve(JSContext* cx, unsigned argc,
Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
RootedValue modulePrivate(
cx, js::GetFunctionNativeReserved(&args.callee(), ModulePrivateSlot));
// Step 4.1. Set specifier to ? ToString(specifier).
//
RootedValue v(cx, args.get(ImportMetaResolveSpecifierArg));
RootedString specifier(cx, JS::ToString(cx, v));
if (!specifier) {
return false;
}
// Step 4.2, 4.3 are implemented in ImportMetaResolveImpl.
RootedString url(cx, ImportMetaResolveImpl(cx, modulePrivate, specifier));
if (!url) {
return false;
}
// Step 4.4. Return the serialization of url.
args.rval().setString(url);
return true;
}
// static
JSString* ModuleLoaderBase::ImportMetaResolveImpl(
JSContext* aCx, JS::Handle<JS::Value> aReferencingPrivate,
JS::Handle<JSString*> aSpecifier) {
RootedString urlString(aCx);
{
// ModuleScript should only live in this block, otherwise it will be a GC
// hazard
RefPtr<ModuleScript> script =
static_cast<ModuleScript*>(aReferencingPrivate.toPrivate());
MOZ_ASSERT(script->IsModuleScript());
MOZ_ASSERT(JS::GetModulePrivate(script->ModuleRecord()) ==
aReferencingPrivate);
RefPtr<ModuleLoaderBase> loader = GetCurrentModuleLoader(aCx);
if (!loader) {
return nullptr;
}
nsAutoJSString specifier;
if (!specifier.init(aCx, aSpecifier)) {
return nullptr;
}
auto result = loader->ResolveModuleSpecifier(script, specifier);
if (result.isErr()) {
JS::Rooted<JS::Value> error(aCx);
nsresult rv = loader->HandleResolveFailure(
aCx, script, specifier, result.unwrapErr(), 0,
JS::ColumnNumberOneOrigin(), &error);
if (NS_FAILED(rv)) {
JS_ReportOutOfMemory(aCx);
return nullptr;
}
JS_SetPendingException(aCx, error);
return nullptr;
}
nsCOMPtr<nsIURI> uri = result.unwrap();
nsAutoCString url;
MOZ_ALWAYS_SUCCEEDS(uri->GetAsciiSpec(url));
urlString.set(JS_NewStringCopyZ(aCx, url.get()));
}
return urlString;
}
// static
bool ModuleLoaderBase::HostPopulateImportMeta(
JSContext* aCx, JS::Handle<JS::Value> aReferencingPrivate,
JS::Handle<JSObject*> aMetaObject) {
RefPtr<ModuleScript> script =
static_cast<ModuleScript*>(aReferencingPrivate.toPrivate());
MOZ_ASSERT(script->IsModuleScript());
MOZ_ASSERT(JS::GetModulePrivate(script->ModuleRecord()) ==
aReferencingPrivate);
nsAutoCString url;
MOZ_DIAGNOSTIC_ASSERT(script->BaseURL());
MOZ_ALWAYS_SUCCEEDS(script->BaseURL()->GetAsciiSpec(url));
JS::Rooted<JSString*> urlString(aCx, JS_NewStringCopyZ(aCx, url.get()));
if (!urlString) {
JS_ReportOutOfMemory(aCx);
return false;
}
if (!JS_DefineProperty(aCx, aMetaObject, "url", urlString,
JSPROP_ENUMERATE)) {
return false;
}
// Define 'resolve' function on the import.meta object.
JSFunction* resolveFunc = js::DefineFunctionWithReserved(
aCx, aMetaObject, "resolve", ImportMetaResolve, ImportMetaResolveNumArgs,
JSPROP_ENUMERATE);
if (!resolveFunc) {
return false;
}
// Store the 'active script' of the meta object into the function slot.
RootedObject resolveFuncObj(aCx, JS_GetFunctionObject(resolveFunc));
js::SetFunctionNativeReserved(resolveFuncObj, ModulePrivateSlot,
aReferencingPrivate);
return true;
}
// static
bool ModuleLoaderBase::HostImportModuleDynamically(
JSContext* aCx, JS::Handle<JS::Value> aReferencingPrivate,
JS::Handle<JSObject*> aModuleRequest, JS::Handle<JSObject*> aPromise) {
MOZ_DIAGNOSTIC_ASSERT(aModuleRequest);
MOZ_DIAGNOSTIC_ASSERT(aPromise);
RefPtr<LoadedScript> script(GetLoadedScriptOrNull(aCx, aReferencingPrivate));
JS::Rooted<JSString*> specifierString(
aCx, JS::GetModuleRequestSpecifier(aCx, aModuleRequest));
if (!specifierString) {
return false;
}
// Attempt to resolve the module specifier.
nsAutoJSString specifier;
if (!specifier.init(aCx, specifierString)) {
return false;
}
RefPtr<ModuleLoaderBase> loader = GetCurrentModuleLoader(aCx);
if (!loader) {
return false;
}
if (!loader->IsDynamicImportSupported()) {
JS_ReportErrorNumberASCII(aCx, js::GetErrorMessage, nullptr,
JSMSG_DYNAMIC_IMPORT_NOT_SUPPORTED);
return false;
}
auto result = loader->ResolveModuleSpecifier(script, specifier);
if (result.isErr()) {
JS::Rooted<JS::Value> error(aCx);
nsresult rv =
loader->HandleResolveFailure(aCx, script, specifier, result.unwrapErr(),
0, JS::ColumnNumberOneOrigin(), &error);
if (NS_FAILED(rv)) {
JS_ReportOutOfMemory(aCx);
return false;
}
JS_SetPendingException(aCx, error);
return false;
}
// Create a new top-level load request.
nsCOMPtr<nsIURI> uri = result.unwrap();
RefPtr<ModuleLoadRequest> request =
loader->CreateDynamicImport(aCx, uri, script, specifierString, aPromise);
if (!request) {
// Throws TypeError if CreateDynamicImport returns nullptr.
JS_ReportErrorNumberASCII(aCx, js::GetErrorMessage, nullptr,
JSMSG_DYNAMIC_IMPORT_NOT_SUPPORTED);
return false;
}
nsresult rv = loader->StartDynamicImport(request);
if (NS_SUCCEEDED(rv)) {
loader->OnDynamicImportStarted(request);
}
return true;
}
AutoOverrideModuleLoader::AutoOverrideModuleLoader(ModuleLoaderBase* aTarget,
ModuleLoaderBase* aLoader)
: mTarget(aTarget) {
mTarget->SetOverride(aLoader);
}
AutoOverrideModuleLoader::~AutoOverrideModuleLoader() {
mTarget->ResetOverride();
}
void ModuleLoaderBase::SetOverride(ModuleLoaderBase* aLoader) {
MOZ_ASSERT(!mOverriddenBy);
MOZ_ASSERT(!aLoader->mOverriddenBy);
MOZ_ASSERT(mGlobalObject == aLoader->mGlobalObject);
mOverriddenBy = aLoader;
}
bool ModuleLoaderBase::IsOverridden() { return !!mOverriddenBy; }
bool ModuleLoaderBase::IsOverriddenBy(ModuleLoaderBase* aLoader) {
return mOverriddenBy == aLoader;
}
void ModuleLoaderBase::ResetOverride() {
MOZ_ASSERT(mOverriddenBy);
mOverriddenBy = nullptr;
}
// static
ModuleLoaderBase* ModuleLoaderBase::GetCurrentModuleLoader(JSContext* aCx) {
auto reportError = mozilla::MakeScopeExit([aCx]() {
JS_ReportErrorASCII(aCx, "No ScriptLoader found for the current context");
});
JS::Rooted<JSObject*> object(aCx, JS::CurrentGlobalOrNull(aCx));
if (!object) {
return nullptr;
}
nsIGlobalObject* global = xpc::NativeGlobal(object);
if (!global) {
return nullptr;
}
ModuleLoaderBase* loader = global->GetModuleLoader(aCx);
if (!loader) {
return nullptr;
}
MOZ_ASSERT(loader->mGlobalObject == global);
reportError.release();
if (loader->mOverriddenBy) {
MOZ_ASSERT(loader->mOverriddenBy->mGlobalObject == global);
return loader->mOverriddenBy;
}
return loader;
}
// static
LoadedScript* ModuleLoaderBase::GetLoadedScriptOrNull(
JSContext* aCx, JS::Handle<JS::Value> aReferencingPrivate) {
if (aReferencingPrivate.isUndefined()) {
return nullptr;
}
auto* script = static_cast<LoadedScript*>(aReferencingPrivate.toPrivate());
MOZ_ASSERT_IF(
script->IsModuleScript(),
JS::GetModulePrivate(script->AsModuleScript()->ModuleRecord()) ==
aReferencingPrivate);
return script;
}
JS::Value PrivateFromLoadedScript(LoadedScript* aScript) {
if (!aScript) {
return JS::UndefinedValue();
}
return JS::PrivateValue(aScript);
}
nsresult ModuleLoaderBase::StartModuleLoad(ModuleLoadRequest* aRequest) {
return StartOrRestartModuleLoad(aRequest, RestartRequest::No);
}
nsresult ModuleLoaderBase::RestartModuleLoad(ModuleLoadRequest* aRequest) {
return StartOrRestartModuleLoad(aRequest, RestartRequest::Yes);
}
nsresult ModuleLoaderBase::StartOrRestartModuleLoad(ModuleLoadRequest* aRequest,
RestartRequest aRestart) {
MOZ_ASSERT(aRequest->mLoader == this);
MOZ_ASSERT(aRequest->IsFetching() || aRequest->IsPendingFetchingError());
aRequest->SetUnknownDataType();
// If we're restarting the request, the module should already be in the
// "fetching" map.
MOZ_ASSERT_IF(aRestart == RestartRequest::Yes,
IsModuleFetching(aRequest->mURI));
// Check with the derived class whether we should load this module.
nsresult rv = NS_OK;
if (!CanStartLoad(aRequest, &rv)) {
return rv;
}
// Check whether the module has been fetched or is currently being fetched,
// and if so wait for it rather than starting a new fetch.
ModuleLoadRequest* request = aRequest->AsModuleRequest();
if (aRestart == RestartRequest::No && ModuleMapContainsURL(request->mURI)) {
LOG(("ScriptLoadRequest (%p): Waiting for module fetch", aRequest));
WaitForModuleFetch(request);
return NS_OK;
}
rv = StartFetch(aRequest);
NS_ENSURE_SUCCESS(rv, rv);
// We successfully started fetching a module so put its URL in the module
// map and mark it as fetching.
if (aRestart == RestartRequest::No) {
SetModuleFetchStarted(aRequest->AsModuleRequest());
}
return NS_OK;
}
bool ModuleLoaderBase::ModuleMapContainsURL(nsIURI* aURL) const {
return IsModuleFetching(aURL) || IsModuleFetched(aURL);
}
bool ModuleLoaderBase::IsModuleFetching(nsIURI* aURL) const {
return mFetchingModules.Contains(aURL);
}
bool ModuleLoaderBase::IsModuleFetched(nsIURI* aURL) const {
return mFetchedModules.Contains(aURL);
}
nsresult ModuleLoaderBase::GetFetchedModuleURLs(nsTArray<nsCString>& aURLs) {
for (const auto& entry : mFetchedModules) {
nsIURI* uri = entry.GetData()->BaseURL();
nsAutoCString spec;
nsresult rv = uri->GetSpec(spec);
NS_ENSURE_SUCCESS(rv, rv);
aURLs.AppendElement(spec);
}
return NS_OK;
}
void ModuleLoaderBase::SetModuleFetchStarted(ModuleLoadRequest* aRequest) {
// Update the module map to indicate that a module is currently being fetched.
MOZ_ASSERT(aRequest->IsFetching() || aRequest->IsPendingFetchingError());
MOZ_ASSERT(!ModuleMapContainsURL(aRequest->mURI));
RefPtr<LoadingRequest> loadingRequest = new LoadingRequest();
loadingRequest->mRequest = aRequest;
mFetchingModules.InsertOrUpdate(aRequest->mURI, loadingRequest);
}
void ModuleLoaderBase::SetModuleFetchFinishedAndResumeWaitingRequests(
ModuleLoadRequest* aRequest, nsresult aResult) {
// Update module map with the result of fetching a single module script.
//
// If any requests for the same URL are waiting on this one to complete, call
// ModuleLoaded or LoadFailed to resume or fail them as appropriate.
MOZ_ASSERT(aRequest->mLoader == this);
LOG(
("ScriptLoadRequest (%p): Module fetch finished (script == %p, result == "
"%u)",
aRequest, aRequest->mModuleScript.get(), unsigned(aResult)));
auto entry = mFetchingModules.Lookup(aRequest->mURI);
if (!entry) {
LOG(
("ScriptLoadRequest (%p): Key not found in mFetchingModules, "
"assuming we have an inline module or have finished fetching already",
aRequest));
return;
}
// It's possible for a request to be cancelled and removed from the fetching
// modules map and a new request started for the same URI and added to the
// map. In this case we don't want the first cancelled request to complete the
// later request (which will cause it to fail) so we ignore it.
RefPtr<LoadingRequest> loadingRequest = entry.Data();
if (loadingRequest->mRequest != aRequest) {
MOZ_ASSERT(aRequest->IsCanceled());
LOG(
("ScriptLoadRequest (%p): Ignoring completion of cancelled request "
"that was removed from the map",
aRequest));
return;
}
MOZ_ALWAYS_TRUE(mFetchingModules.Remove(aRequest->mURI));
RefPtr<ModuleScript> moduleScript(aRequest->mModuleScript);
MOZ_ASSERT(NS_FAILED(aResult) == !moduleScript);
mFetchedModules.InsertOrUpdate(aRequest->mURI, RefPtr{moduleScript});
LOG(("ScriptLoadRequest (%p): Resuming waiting requests", aRequest));
MOZ_ASSERT(loadingRequest->mRequest == aRequest);
ResumeWaitingRequests(loadingRequest, bool(moduleScript));
}
void ModuleLoaderBase::ResumeWaitingRequests(LoadingRequest* aLoadingRequest,
bool aSuccess) {
for (ModuleLoadRequest* request : aLoadingRequest->mWaiting) {
ResumeWaitingRequest(request, aSuccess);
}
}
void ModuleLoaderBase::ResumeWaitingRequest(ModuleLoadRequest* aRequest,
bool aSuccess) {
if (aSuccess) {
aRequest->ModuleLoaded();
} else {
aRequest->LoadFailed();
}
}
void ModuleLoaderBase::WaitForModuleFetch(ModuleLoadRequest* aRequest) {
nsIURI* uri = aRequest->mURI;
MOZ_ASSERT(ModuleMapContainsURL(uri));
if (auto entry = mFetchingModules.Lookup(uri)) {
RefPtr<LoadingRequest> loadingRequest = entry.Data();
loadingRequest->mWaiting.AppendElement(aRequest);
return;
}
RefPtr<ModuleScript> ms;
MOZ_ALWAYS_TRUE(mFetchedModules.Get(uri, getter_AddRefs(ms)));
ResumeWaitingRequest(aRequest, bool(ms));
}
ModuleScript* ModuleLoaderBase::GetFetchedModule(nsIURI* aURL) const {
if (LOG_ENABLED()) {
nsAutoCString url;
aURL->GetAsciiSpec(url);
LOG(("GetFetchedModule %s", url.get()));
}
bool found;
ModuleScript* ms = mFetchedModules.GetWeak(aURL, &found);
MOZ_ASSERT(found);
return ms;
}
nsresult ModuleLoaderBase::OnFetchComplete(ModuleLoadRequest* aRequest,
nsresult aRv) {
MOZ_ASSERT(aRequest->mLoader == this);
MOZ_ASSERT(!aRequest->mModuleScript);
nsresult rv = aRv;
if (NS_SUCCEEDED(rv)) {
rv = CreateModuleScript(aRequest);
// If a module script was created, it should either have a module record
// object or a parse error.
if (ModuleScript* ms = aRequest->mModuleScript) {
MOZ_DIAGNOSTIC_ASSERT(bool(ms->ModuleRecord()) != ms->HasParseError());
}
aRequest->ClearScriptSource();
if (NS_FAILED(rv)) {
aRequest->LoadFailed();
return rv;
}
}
MOZ_ASSERT(NS_SUCCEEDED(rv) == bool(aRequest->mModuleScript));
SetModuleFetchFinishedAndResumeWaitingRequests(aRequest, rv);
if (!aRequest->IsErrored()) {
StartFetchingModuleDependencies(aRequest);
}
return NS_OK;
}
nsresult ModuleLoaderBase::CreateModuleScript(ModuleLoadRequest* aRequest) {
MOZ_ASSERT(!aRequest->mModuleScript);
MOZ_ASSERT(aRequest->mBaseURL);
LOG(("ScriptLoadRequest (%p): Create module script", aRequest));
AutoJSAPI jsapi;
if (!jsapi.Init(mGlobalObject)) {
return NS_ERROR_FAILURE;
}
nsresult rv;
{
JSContext* cx = jsapi.cx();
JS::Rooted<JSObject*> module(cx);
JS::CompileOptions options(cx);
JS::RootedScript introductionScript(cx);
rv = mLoader->FillCompileOptionsForRequest(cx, aRequest, &options,
&introductionScript);
if (NS_SUCCEEDED(rv)) {
JS::Rooted<JSObject*> global(cx, mGlobalObject->GetGlobalJSObject());
rv = CompileFetchedModule(cx, global, options, aRequest, &module);
}
MOZ_DIAGNOSTIC_ASSERT(NS_SUCCEEDED(rv) == (module != nullptr));
if (module) {
JS::RootedValue privateValue(cx);
JS::RootedScript moduleScript(cx, JS::GetModuleScript(module));
JS::InstantiateOptions instantiateOptions(options);
if (!JS::UpdateDebugMetadata(cx, moduleScript, instantiateOptions,
privateValue, nullptr, introductionScript,
nullptr)) {
return NS_ERROR_OUT_OF_MEMORY;
}
}
MOZ_ASSERT(aRequest->mLoadedScript->IsModuleScript());
MOZ_ASSERT(aRequest->mLoadedScript->GetFetchOptions() ==
aRequest->mFetchOptions);
MOZ_ASSERT(aRequest->mLoadedScript->GetURI() == aRequest->mURI);
aRequest->mLoadedScript->SetBaseURL(aRequest->mBaseURL);
RefPtr<ModuleScript> moduleScript =
aRequest->mLoadedScript->AsModuleScript();
aRequest->mModuleScript = moduleScript;
moduleScript->SetForPreload(aRequest->mLoadContext->IsPreload());
moduleScript->SetHadImportMap(HasImportMapRegistered());
if (!module) {
LOG(("ScriptLoadRequest (%p): compilation failed (%d)", aRequest,
unsigned(rv)));
JS::Rooted<JS::Value> error(cx);
if (!jsapi.HasException() || !jsapi.StealException(&error) ||
error.isUndefined()) {
aRequest->mModuleScript = nullptr;
return NS_ERROR_FAILURE;
}
moduleScript->SetParseError(error);
aRequest->ModuleErrored();
return NS_OK;
}
moduleScript->SetModuleRecord(module);
// Validate requested modules and treat failure to resolve module specifiers
// the same as a parse error.
rv = ResolveRequestedModules(aRequest, nullptr);
if (NS_FAILED(rv)) {
if (!aRequest->IsErrored()) {
aRequest->mModuleScript = nullptr;
return rv;
}
aRequest->ModuleErrored();
return NS_OK;
}
}
LOG(("ScriptLoadRequest (%p): module script == %p", aRequest,
aRequest->mModuleScript.get()));
return rv;
}
nsresult ModuleLoaderBase::GetResolveFailureMessage(ResolveError aError,
const nsAString& aSpecifier,
nsAString& aResult) {
AutoTArray<nsString, 1> errorParams;
errorParams.AppendElement(aSpecifier);
nsresult rv = nsContentUtils::FormatLocalizedString(
nsContentUtils::eDOM_PROPERTIES, ResolveErrorInfo::GetString(aError),
errorParams, aResult);
NS_ENSURE_SUCCESS(rv, rv);
return NS_OK;
}
nsresult ModuleLoaderBase::HandleResolveFailure(
JSContext* aCx, LoadedScript* aScript, const nsAString& aSpecifier,
ResolveError aError, uint32_t aLineNumber,
JS::ColumnNumberOneOrigin aColumnNumber,
JS::MutableHandle<JS::Value> aErrorOut) {
JS::Rooted<JSString*> filename(aCx);
if (aScript) {
nsAutoCString url;
aScript->BaseURL()->GetAsciiSpec(url);
filename = JS_NewStringCopyZ(aCx, url.get());
} else {
filename = JS_NewStringCopyZ(aCx, "(unknown)");
}
if (!filename) {
return NS_ERROR_OUT_OF_MEMORY;
}
nsAutoString errorText;
nsresult rv = GetResolveFailureMessage(aError, aSpecifier, errorText);
NS_ENSURE_SUCCESS(rv, rv);
JS::Rooted<JSString*> string(aCx, JS_NewUCStringCopyZ(aCx, errorText.get()));
if (!string) {
return NS_ERROR_OUT_OF_MEMORY;
}
if (!JS::CreateError(aCx, JSEXN_TYPEERR, nullptr, filename, aLineNumber,
aColumnNumber, nullptr, string, JS::NothingHandleValue,
aErrorOut)) {
return NS_ERROR_OUT_OF_MEMORY;
}
return NS_OK;
}
ResolveResult ModuleLoaderBase::ResolveModuleSpecifier(
LoadedScript* aScript, const nsAString& aSpecifier) {
// Import Maps are not supported on workers/worklets.
MOZ_ASSERT_IF(!NS_IsMainThread(), mImportMap == nullptr);
// Forward to the updated 'Resolve a module specifier' algorithm defined in
// the Import Maps spec.
return ImportMap::ResolveModuleSpecifier(mImportMap.get(), mLoader, aScript,
aSpecifier);
}
nsresult ModuleLoaderBase::ResolveRequestedModules(
ModuleLoadRequest* aRequest, nsCOMArray<nsIURI>* aUrlsOut) {
ModuleScript* ms = aRequest->mModuleScript;
AutoJSAPI jsapi;
if (!jsapi.Init(mGlobalObject)) {
return NS_ERROR_FAILURE;
}
JSContext* cx = jsapi.cx();
JS::Rooted<JSObject*> moduleRecord(cx, ms->ModuleRecord());
uint32_t length = JS::GetRequestedModulesCount(cx, moduleRecord);
for (uint32_t i = 0; i < length; i++) {
JS::Rooted<JSString*> str(
cx, JS::GetRequestedModuleSpecifier(cx, moduleRecord, i));
MOZ_ASSERT(str);
nsAutoJSString specifier;
if (!specifier.init(cx, str)) {
return NS_ERROR_FAILURE;
}
// Let url be the result of resolving a module specifier given module script
// and requested.
ModuleLoaderBase* loader = aRequest->mLoader;
auto result = loader->ResolveModuleSpecifier(ms, specifier);
if (result.isErr()) {
uint32_t lineNumber = 0;
JS::ColumnNumberOneOrigin columnNumber;
JS::GetRequestedModuleSourcePos(cx, moduleRecord, i, &lineNumber,
&columnNumber);
JS::Rooted<JS::Value> error(cx);
nsresult rv =
loader->HandleResolveFailure(cx, ms, specifier, result.unwrapErr(),
lineNumber, columnNumber, &error);
NS_ENSURE_SUCCESS(rv, rv);
ms->SetParseError(error);
return NS_ERROR_FAILURE;
}
nsCOMPtr<nsIURI> uri = result.unwrap();
if (aUrlsOut) {
aUrlsOut->AppendElement(uri.forget());
}
}
return NS_OK;
}
void ModuleLoaderBase::StartFetchingModuleDependencies(
ModuleLoadRequest* aRequest) {
LOG(("ScriptLoadRequest (%p): Start fetching module dependencies", aRequest));
if (aRequest->IsCanceled()) {
return;
}
MOZ_ASSERT(aRequest->mModuleScript);
MOZ_ASSERT(!aRequest->mModuleScript->HasParseError());
MOZ_ASSERT(aRequest->IsFetching() || aRequest->IsCompiling());
auto visitedSet = aRequest->mVisitedSet;
MOZ_ASSERT(visitedSet->Contains(aRequest->mURI));
aRequest->mState = ModuleLoadRequest::State::LoadingImports;
nsCOMArray<nsIURI> urls;
nsresult rv = ResolveRequestedModules(aRequest, &urls);
if (NS_FAILED(rv)) {
aRequest->mModuleScript = nullptr;
aRequest->ModuleErrored();
return;
}
// Remove already visited URLs from the list. Put unvisited URLs into the
// visited set.
int32_t i = 0;
while (i < urls.Count()) {
nsIURI* url = urls[i];
if (visitedSet->Contains(url)) {
urls.RemoveObjectAt(i);
} else {
visitedSet->PutEntry(url);
i++;
}
}
if (urls.Count() == 0) {
// There are no descendants to load so this request is ready.
aRequest->DependenciesLoaded();
return;
}
MOZ_ASSERT(aRequest->mAwaitingImports == 0);
aRequest->mAwaitingImports = urls.Count();
// For each url in urls, fetch a module script graph given url, module
// script's CORS setting, and module script's settings object.
for (auto* url : urls) {
StartFetchingModuleAndDependencies(aRequest, url);
}
}
void ModuleLoaderBase::StartFetchingModuleAndDependencies(
ModuleLoadRequest* aParent, nsIURI* aURI) {
MOZ_ASSERT(aURI);
RefPtr<ModuleLoadRequest> childRequest = CreateStaticImport(aURI, aParent);
aParent->mImports.AppendElement(childRequest);
if (LOG_ENABLED()) {
nsAutoCString url1;
aParent->mURI->GetAsciiSpec(url1);
nsAutoCString url2;
aURI->GetAsciiSpec(url2);
LOG(("ScriptLoadRequest (%p): Start fetching dependency %p", aParent,
childRequest.get()));
LOG(("StartFetchingModuleAndDependencies \"%s\" -> \"%s\"", url1.get(),
url2.get()));
}
MOZ_ASSERT(!childRequest->mWaitingParentRequest);
childRequest->mWaitingParentRequest = aParent;
nsresult rv = StartModuleLoad(childRequest);
if (NS_FAILED(rv)) {
MOZ_ASSERT(!childRequest->mModuleScript);
LOG(("ScriptLoadRequest (%p): rejecting %p", aParent,
childRequest.get()));
mLoader->ReportErrorToConsole(childRequest, rv);
childRequest->LoadFailed();
}
}
void ModuleLoadRequest::ChildLoadComplete(bool aSuccess) {
RefPtr<ModuleLoadRequest> parent = mWaitingParentRequest;
MOZ_ASSERT(parent);
MOZ_ASSERT(parent->mAwaitingImports != 0);
mWaitingParentRequest = nullptr;
parent->mAwaitingImports--;
if (parent->IsFinished()) {
MOZ_ASSERT_IF(!aSuccess, parent->IsErrored());
return;
}
if (!aSuccess) {
parent->ModuleErrored();
} else if (parent->mAwaitingImports == 0) {
parent->DependenciesLoaded();
}
}
nsresult ModuleLoaderBase::StartDynamicImport(ModuleLoadRequest* aRequest) {
MOZ_ASSERT(aRequest->mLoader == this);
LOG(("ScriptLoadRequest (%p): Start dynamic import", aRequest));
mDynamicImportRequests.AppendElement(aRequest);
nsresult rv = StartModuleLoad(aRequest);
if (NS_FAILED(rv)) {
mLoader->ReportErrorToConsole(aRequest, rv);
FinishDynamicImportAndReject(aRequest, rv);
}
return rv;
}
void ModuleLoaderBase::FinishDynamicImportAndReject(ModuleLoadRequest* aRequest,
nsresult aResult) {
AutoJSAPI jsapi;
MOZ_ASSERT(NS_FAILED(aResult));
if (!jsapi.Init(mGlobalObject)) {
return;
}
FinishDynamicImport(jsapi.cx(), aRequest, aResult, nullptr);
}
/* static */
void ModuleLoaderBase::FinishDynamicImport(
JSContext* aCx, ModuleLoadRequest* aRequest, nsresult aResult,
JS::Handle<JSObject*> aEvaluationPromise) {
LOG(("ScriptLoadRequest (%p): Finish dynamic import %x %d", aRequest,
unsigned(aResult), JS_IsExceptionPending(aCx)));
MOZ_ASSERT_IF(NS_SUCCEEDED(aResult),
GetCurrentModuleLoader(aCx) == aRequest->mLoader);
// For failure case, aRequest may have already been unlinked by CC.
MOZ_ASSERT_IF(
NS_FAILED(aResult),
GetCurrentModuleLoader(aCx) == aRequest->mLoader || !aRequest->mLoader);
// If aResult is a failed result, we don't have an EvaluationPromise. If it
// succeeded, evaluationPromise may still be null, but in this case it will
// be handled by rejecting the dynamic module import promise in the JSAPI.
MOZ_ASSERT_IF(NS_FAILED(aResult), !aEvaluationPromise);
// Complete the dynamic import, report failures indicated by aResult or as a
// pending exception on the context.
if (!aRequest->mDynamicPromise) {
// Import has already been completed.
return;
}
if (NS_FAILED(aResult) &&
aResult != NS_SUCCESS_DOM_SCRIPT_EVALUATION_THREW_UNCATCHABLE) {
MOZ_ASSERT(!JS_IsExceptionPending(aCx));
nsAutoCString url;
aRequest->mURI->GetSpec(url);
JS_ReportErrorNumberASCII(aCx, js::GetErrorMessage, nullptr,
JSMSG_DYNAMIC_IMPORT_FAILED, url.get());
}
JS::Rooted<JS::Value> referencingScript(
aCx, PrivateFromLoadedScript(aRequest->mDynamicReferencingScript));
JS::Rooted<JSString*> specifier(aCx, aRequest->mDynamicSpecifier);
JS::Rooted<JSObject*> promise(aCx, aRequest->mDynamicPromise);
JS::Rooted<JSObject*> moduleRequest(aCx,
JS::CreateModuleRequest(aCx, specifier));
JS::FinishDynamicModuleImport(aCx, aEvaluationPromise, referencingScript,
moduleRequest, promise);
// FinishDynamicModuleImport clears any pending exception.
MOZ_ASSERT(!JS_IsExceptionPending(aCx));
aRequest->ClearDynamicImport();
}
ModuleLoaderBase::ModuleLoaderBase(ScriptLoaderInterface* aLoader,
nsIGlobalObject* aGlobalObject)
: mGlobalObject(aGlobalObject), mLoader(aLoader) {
MOZ_ASSERT(mGlobalObject);
MOZ_ASSERT(mLoader);
EnsureModuleHooksInitialized();
}
ModuleLoaderBase::~ModuleLoaderBase() {
mDynamicImportRequests.CancelRequestsAndClear();
LOG(("ModuleLoaderBase::~ModuleLoaderBase %p", this));
}
void ModuleLoaderBase::Shutdown() {
CancelAndClearDynamicImports();
for (const auto& entry : mFetchingModules) {
RefPtr<LoadingRequest> loadingRequest(entry.GetData());
if (loadingRequest) {
ResumeWaitingRequests(loadingRequest, false);
}
}
for (const auto& entry : mFetchedModules) {
if (entry.GetData()) {
entry.GetData()->Shutdown();
}
}
mFetchingModules.Clear();
mFetchedModules.Clear();
mGlobalObject = nullptr;
mLoader = nullptr;
}
bool ModuleLoaderBase::HasFetchingModules() const {
return !mFetchingModules.IsEmpty();
}
bool ModuleLoaderBase::HasPendingDynamicImports() const {
return !mDynamicImportRequests.isEmpty();
}
void ModuleLoaderBase::CancelDynamicImport(ModuleLoadRequest* aRequest,
nsresult aResult) {
// aRequest may have already been unlinked by CC.
MOZ_ASSERT(aRequest->mLoader == this || !aRequest->mLoader);
RefPtr<ScriptLoadRequest> req = mDynamicImportRequests.Steal(aRequest);
if (!aRequest->IsCanceled()) {
aRequest->Cancel();
// FinishDynamicImport must happen exactly once for each dynamic import
// request. If the load is aborted we do it when we remove the request
// from mDynamicImportRequests.
FinishDynamicImportAndReject(aRequest, aResult);
}
}
void ModuleLoaderBase::RemoveDynamicImport(ModuleLoadRequest* aRequest) {
MOZ_ASSERT(aRequest->IsDynamicImport());
mDynamicImportRequests.Remove(aRequest);
}
#ifdef DEBUG
bool ModuleLoaderBase::HasDynamicImport(
const ModuleLoadRequest* aRequest) const {
MOZ_ASSERT(aRequest->mLoader == this);
return mDynamicImportRequests.Contains(
const_cast<ModuleLoadRequest*>(aRequest));
}
#endif
JS::Value ModuleLoaderBase::FindFirstParseError(ModuleLoadRequest* aRequest) {
MOZ_ASSERT(aRequest);
ModuleScript* moduleScript = aRequest->mModuleScript;
MOZ_ASSERT(moduleScript);
if (moduleScript->HasParseError()) {
return moduleScript->ParseError();
}
for (ModuleLoadRequest* childRequest : aRequest->mImports) {
MOZ_DIAGNOSTIC_ASSERT(moduleScript->HadImportMap() ==
childRequest->mModuleScript->HadImportMap());
JS::Value error = FindFirstParseError(childRequest);
if (!error.isUndefined()) {
return error;
}
}
return JS::UndefinedValue();
}
bool ModuleLoaderBase::InstantiateModuleGraph(ModuleLoadRequest* aRequest) {
// Instantiate a top-level module and record any error.
MOZ_ASSERT(aRequest);
MOZ_ASSERT(aRequest->mLoader == this);
MOZ_ASSERT(aRequest->IsTopLevel());
LOG(("ScriptLoadRequest (%p): Instantiate module graph", aRequest));
AUTO_PROFILER_LABEL("ModuleLoaderBase::InstantiateModuleGraph", JS);
ModuleScript* moduleScript = aRequest->mModuleScript;
MOZ_ASSERT(moduleScript);
JS::Value parseError = FindFirstParseError(aRequest);
if (!parseError.isUndefined()) {
moduleScript->SetErrorToRethrow(parseError);
LOG(("ScriptLoadRequest (%p): found parse error", aRequest));
return true;
}
MOZ_ASSERT(moduleScript->ModuleRecord());
AutoJSAPI jsapi;
if (NS_WARN_IF(!jsapi.Init(mGlobalObject))) {
return false;
}
JS::Rooted<JSObject*> module(jsapi.cx(), moduleScript->ModuleRecord());
if (!xpc::Scriptability::AllowedIfExists(module)) {
return true;
}
if (!JS::ModuleLink(jsapi.cx(), module)) {
LOG(("ScriptLoadRequest (%p): Instantiate failed", aRequest));
MOZ_ASSERT(jsapi.HasException());
JS::RootedValue exception(jsapi.cx());
if (!jsapi.StealException(&exception)) {
return false;
}
MOZ_ASSERT(!exception.isUndefined());
moduleScript->SetErrorToRethrow(exception);
}
return true;
}
nsresult ModuleLoaderBase::InitDebuggerDataForModuleGraph(
JSContext* aCx, ModuleLoadRequest* aRequest) {
// JS scripts can be associated with a DOM element for use by the debugger,
// but preloading can cause scripts to be compiled before DOM script element
// nodes have been created. This method ensures that this association takes
// place before the first time a module script is run.
MOZ_ASSERT(aRequest);
ModuleScript* moduleScript = aRequest->mModuleScript;
if (moduleScript->DebuggerDataInitialized()) {
return NS_OK;
}
for (ModuleLoadRequest* childRequest : aRequest->mImports) {
nsresult rv = InitDebuggerDataForModuleGraph(aCx, childRequest);
NS_ENSURE_SUCCESS(rv, rv);
}
JS::Rooted<JSObject*> module(aCx, moduleScript->ModuleRecord());
MOZ_ASSERT(module);
// The script is now ready to be exposed to the debugger.
JS::Rooted<JSScript*> script(aCx, JS::GetModuleScript(module));
JS::ExposeScriptToDebugger(aCx, script);
moduleScript->SetDebuggerDataInitialized();
return NS_OK;
}
void ModuleLoaderBase::ProcessDynamicImport(ModuleLoadRequest* aRequest) {
if (!aRequest->mModuleScript) {
FinishDynamicImportAndReject(aRequest, NS_ERROR_FAILURE);
return;
}
InstantiateAndEvaluateDynamicImport(aRequest);
}
void ModuleLoaderBase::InstantiateAndEvaluateDynamicImport(
ModuleLoadRequest* aRequest) {
MOZ_ASSERT(aRequest->mModuleScript);
if (!InstantiateModuleGraph(aRequest)) {
aRequest->mModuleScript = nullptr;
}
nsresult rv = NS_ERROR_FAILURE;
if (aRequest->mModuleScript) {
rv = EvaluateModule(aRequest);
}
if (NS_FAILED(rv)) {
FinishDynamicImportAndReject(aRequest, rv);
}
}
nsresult ModuleLoaderBase::EvaluateModule(ModuleLoadRequest* aRequest) {
MOZ_ASSERT(aRequest->mLoader == this);
mozilla::nsAutoMicroTask mt;
mozilla::dom::AutoEntryScript aes(mGlobalObject, "EvaluateModule",
NS_IsMainThread());
return EvaluateModuleInContext(aes.cx(), aRequest,
JS::ReportModuleErrorsAsync);
}
nsresult ModuleLoaderBase::EvaluateModuleInContext(
JSContext* aCx, ModuleLoadRequest* aRequest,
JS::ModuleErrorBehaviour errorBehaviour) {
MOZ_ASSERT(aRequest->mLoader == this);
MOZ_ASSERT_IF(!mGlobalObject->GetModuleLoader(aCx)->IsOverridden(),
mGlobalObject->GetModuleLoader(aCx) == this);
MOZ_ASSERT_IF(mGlobalObject->GetModuleLoader(aCx)->IsOverridden(),
mGlobalObject->GetModuleLoader(aCx)->IsOverriddenBy(this));
AUTO_PROFILER_LABEL("ModuleLoaderBase::EvaluateModule", JS);
nsAutoCString profilerLabelString;
if (aRequest->HasScriptLoadContext()) {
aRequest->GetScriptLoadContext()->GetProfilerLabel(profilerLabelString);
}
LOG(("ScriptLoadRequest (%p): Evaluate Module", aRequest));
AUTO_PROFILER_MARKER_TEXT("ModuleEvaluation", JS,
MarkerInnerWindowIdFromJSContext(aCx),
profilerLabelString);
ModuleLoadRequest* request = aRequest->AsModuleRequest();
MOZ_ASSERT(request->mModuleScript);
MOZ_ASSERT_IF(request->HasScriptLoadContext(),
!request->GetScriptLoadContext()->mCompileOrDecodeTask);
ModuleScript* moduleScript = request->mModuleScript;
if (moduleScript->HasErrorToRethrow()) {
LOG(("ScriptLoadRequest (%p): module has error to rethrow", aRequest));
JS::Rooted<JS::Value> error(aCx, moduleScript->ErrorToRethrow());
JS_SetPendingException(aCx, error);
// For a dynamic import, the promise is rejected. Otherwise an error
// is either reported by AutoEntryScript.
if (request->IsDynamicImport()) {
FinishDynamicImport(aCx, request, NS_OK, nullptr);
}
return NS_OK;
}
JS::Rooted<JSObject*> module(aCx, moduleScript->ModuleRecord());
MOZ_ASSERT(module);
MOZ_ASSERT(CurrentGlobalOrNull(aCx) == GetNonCCWObjectGlobal(module));
if (!xpc::Scriptability::AllowedIfExists(module)) {
return NS_OK;
}
nsresult rv = InitDebuggerDataForModuleGraph(aCx, request);
NS_ENSURE_SUCCESS(rv, rv);
if (request->HasScriptLoadContext()) {
TRACE_FOR_TEST(aRequest->GetScriptLoadContext()->GetScriptElement(),
"scriptloader_evaluate_module");
}
JS::Rooted<JS::Value> rval(aCx);
mLoader->MaybePrepareModuleForBytecodeEncodingBeforeExecute(aCx, request);
bool ok = JS::ModuleEvaluate(aCx, module, &rval);
// ModuleEvaluate will usually set a pending exception if it returns false,
// unless the user cancels execution.
MOZ_ASSERT_IF(ok, !JS_IsExceptionPending(aCx));
if (!ok || IsModuleEvaluationAborted(request)) {
LOG(("ScriptLoadRequest (%p): evaluation failed", aRequest));
// For a dynamic import, the promise is rejected. Otherwise an error is
// reported by AutoEntryScript.
rv = NS_ERROR_ABORT;
}
// ModuleEvaluate returns a promise unless the user cancels the execution in
// which case rval will be undefined. We should treat it as a failed
// evaluation, and reject appropriately.
JS::Rooted<JSObject*> evaluationPromise(aCx);
if (rval.isObject()) {
evaluationPromise.set(&rval.toObject());
}
if (request->IsDynamicImport()) {
if (NS_FAILED(rv)) {
FinishDynamicImportAndReject(request, rv);
} else {
FinishDynamicImport(aCx, request, NS_OK, evaluationPromise);
}
} else {
// If this is not a dynamic import, and if the promise is rejected,
// the value is unwrapped from the promise value.
if (!JS::ThrowOnModuleEvaluationFailure(aCx, evaluationPromise,
errorBehaviour)) {
LOG(("ScriptLoadRequest (%p): evaluation failed on throw", aRequest));
// For a dynamic import, the promise is rejected. Otherwise an error is
// reported by AutoEntryScript.
}
}
rv = mLoader->MaybePrepareModuleForBytecodeEncodingAfterExecute(request,
NS_OK);
mLoader->MaybeTriggerBytecodeEncoding();
return rv;
}
void ModuleLoaderBase::CancelAndClearDynamicImports() {
while (ScriptLoadRequest* req = mDynamicImportRequests.getFirst()) {
// This also removes the request from the list.
CancelDynamicImport(req->AsModuleRequest(), NS_ERROR_ABORT);
}
}
UniquePtr<ImportMap> ModuleLoaderBase::ParseImportMap(
ScriptLoadRequest* aRequest) {
AutoJSAPI jsapi;
if (!jsapi.Init(GetGlobalObject())) {
return nullptr;
}
MOZ_ASSERT(aRequest->IsTextSource());
MaybeSourceText maybeSource;
nsresult rv = aRequest->GetScriptSource(jsapi.cx(), &maybeSource,
aRequest->mLoadContext.get());
if (NS_FAILED(rv)) {
return nullptr;
}
JS::SourceText<char16_t>& text = maybeSource.ref<SourceText<char16_t>>();
ReportWarningHelper warning{mLoader, aRequest};
// Step 2. Parse an import map string given input and baseURL, catching any
// exceptions. If this threw an exception, then set result's error to rethrow
// to that exception. Otherwise, set result's import map to the return value.
//
// Step 1. If result's error to rethrow is not null, then report the exception
// given by result's error to rethrow and return.
//
// Impl note: We didn't implement 'Import map parse result' from the spec,
// As the struct has another item called 'error to rethow' to store the
// exception thrown during parsing import-maps, and report that exception
// while registering an import map. Currently only inline import-maps are
// supported, therefore parsing and registering import-maps will be executed
// consecutively. To simplify the implementation, we didn't create the 'error
// to rethow' item and report the exception immediately(done in ~AutoJSAPI).
return ImportMap::ParseString(jsapi.cx(), text, aRequest->mBaseURL, warning);
}
void ModuleLoaderBase::RegisterImportMap(UniquePtr<ImportMap> aImportMap) {
// Check for aImportMap is done in ScriptLoader.
MOZ_ASSERT(aImportMap);
// The step 1(report the exception if there's an error) is done in
// ParseImportMap.
//
// Step 2. Assert: global's import map is an empty import map.
// Impl note: The default import map from the spec is an empty import map, but
// from the implementation it defaults to nullptr, so we check if the global's
// import map is null here.
//
// Also see
MOZ_ASSERT(!mImportMap);
// Step 3. Set global's import map to result's import map.
mImportMap = std::move(aImportMap);
// Any import resolution has been invalidated by the addition of the import
// map. If speculative preloading is currently fetching any modules then
// cancel their requests and remove them from the map.
//
// The cancelled requests will still complete later so we have to check this
// in SetModuleFetchFinishedAndResumeWaitingRequests.
for (const auto& entry : mFetchingModules) {
LoadingRequest* loadingRequest = entry.GetData();
MOZ_DIAGNOSTIC_ASSERT(loadingRequest->mRequest->mLoadContext->IsPreload());
loadingRequest->mRequest->Cancel();
for (const auto& request : loadingRequest->mWaiting) {
MOZ_DIAGNOSTIC_ASSERT(request->mLoadContext->IsPreload());
request->Cancel();
}
}
mFetchingModules.Clear();
// If speculative preloading has added modules to the module map, remove
// them.
for (const auto& entry : mFetchedModules) {
ModuleScript* script = entry.GetData();
if (script) {
MOZ_DIAGNOSTIC_ASSERT(
script->ForPreload(),
"Non-preload module loads should block import maps");
MOZ_DIAGNOSTIC_ASSERT(!script->HadImportMap(),
"Only one import map can be registered");
if (JSObject* module = script->ModuleRecord()) {
MOZ_DIAGNOSTIC_ASSERT(!JS::ModuleIsLinked(module));
}
script->Shutdown();
}
}
mFetchedModules.Clear();
}
void ModuleLoaderBase::CopyModulesTo(ModuleLoaderBase* aDest) {
MOZ_ASSERT(aDest->mFetchingModules.IsEmpty());
MOZ_ASSERT(aDest->mFetchedModules.IsEmpty());
MOZ_ASSERT(mFetchingModules.IsEmpty());
for (const auto& entry : mFetchedModules) {
RefPtr<ModuleScript> moduleScript = entry.GetData();
if (!moduleScript) {
continue;
}
aDest->mFetchedModules.InsertOrUpdate(entry.GetKey(), moduleScript);
}
}
void ModuleLoaderBase::MoveModulesTo(ModuleLoaderBase* aDest) {
MOZ_ASSERT(mFetchingModules.IsEmpty());
MOZ_ASSERT(aDest->mFetchingModules.IsEmpty());
for (const auto& entry : mFetchedModules) {
RefPtr<ModuleScript> moduleScript = entry.GetData();
if (!moduleScript) {
continue;
}
#ifdef DEBUG
if (auto existingEntry = aDest->mFetchedModules.Lookup(entry.GetKey())) {
MOZ_ASSERT(moduleScript == existingEntry.Data());
}
#endif
aDest->mFetchedModules.InsertOrUpdate(entry.GetKey(), moduleScript);
}
mFetchedModules.Clear();
}
#undef LOG
#undef LOG_ENABLED
} // namespace JS::loader