mirrors/bun.sh
1
0
Fork 0
mirror of https://github.com/oven-sh/bun synced 2026-02-15 21:32:05 +00:00
Code Issues Packages Projects Releases Wiki Activity

Runtime support for __esModule annotations (#3393)

Browse Source 
* Runtime support for `__esModule` annotations

* Ignore `__esModule` annotation when `"type": "module"` is set

---------

Co-authored-by: Jarred Sumner <709451+Jarred-Sumner@users.noreply.github.com>
This commit is contained in:
Jarred Sumner
2023-06-26 12:49:20 -07:00
committed by GitHub
parent 6d01e6e367
commit a732999da5
17 changed files with 221 additions and 15 deletions
Download Patch File Download Diff File Expand all files Collapse all files

113
src/bun.js/bindings/CommonJSModuleRecord.cpp
View File

@@ -586,13 +586,41 @@ void JSCommonJSModule::toSyntheticSource(JSC::JSGlobalObject* globalObject,
auto result = this->exportsObject();
auto& vm = globalObject->vm();
exportNames.append(vm.propertyNames->defaultKeyword);
exportValues.append(result);
// This exists to tell ImportMetaObject.ts that this is a CommonJS module.
exportNames.append(Identifier::fromUid(vm.symbolRegistry().symbolForKey("CommonJS"_s)));
exportValues.append(jsNumber(0));
// Bun's intepretation of the "__esModule" annotation:
//
// - If a "default" export does not exist OR the __esModule annotation is not present, then we
// set the default export to the exports object
//
// - If a "default" export also exists, then we set the default export
// to the value of it (matching Babel behavior)
//
// https://stackoverflow.com/questions/50943704/whats-the-purpose-of-object-definepropertyexports-esmodule-value-0
// https://github.com/nodejs/node/issues/40891
// https://github.com/evanw/bundler-esm-cjs-tests
// https://github.com/evanw/esbuild/issues/1591
// https://github.com/oven-sh/bun/issues/3383
//
// Note that this interpretation is slightly different
//
// - We do not ignore when "type": "module" or when the file
// extension is ".mjs". Build tools determine that based on the
// caller's behavior, but in a JS runtime, there is only one ModuleNamespaceObject.
//
// It would be possible to match the behavior at runtime, but
// it would need further engine changes which do not match the ES Module spec
//
// - We ignore the value of the annotation. We only look for the
// existence of the value being set. This is for performance reasons, but also
// this annotation is meant for tooling and the only usages of setting
// it to something that does NOT evaluate to "true" I could find were in
// unit tests of build tools. Happy to revisit this if users file an issue.
bool needsToAssignDefault = true;
if (result.isObject()) {
auto* exports = asObject(result);
@@ -601,21 +629,78 @@ void JSCommonJSModule::toSyntheticSource(JSC::JSGlobalObject* globalObject,
exportNames.reserveCapacity(size + 2);
exportValues.ensureCapacity(size + 2);
if (canPerformFastEnumeration(structure)) {
auto catchScope = DECLARE_CATCH_SCOPE(vm);
Identifier esModuleMarker = builtinNames(vm).__esModulePublicName();
bool hasESModuleMarker = !this->ignoreESModuleAnnotation && exports->hasProperty(globalObject, esModuleMarker);
if (catchScope.exception()) {
catchScope.clearException();
}
if (hasESModuleMarker) {
if (canPerformFastEnumeration(structure)) {
exports->structure()->forEachProperty(vm, [&](const PropertyTableEntry& entry) -> bool {
auto key = entry.key();
if (key->isSymbol() || entry.attributes() & PropertyAttribute::DontEnum || key == esModuleMarker)
return true;
needsToAssignDefault = needsToAssignDefault && key != vm.propertyNames->defaultKeyword;
JSValue value = exports->getDirect(entry.offset());
exportNames.append(Identifier::fromUid(vm, key));
exportValues.append(value);
return true;
});
} else {
JSC::PropertyNameArray properties(vm, JSC::PropertyNameMode::Strings, JSC::PrivateSymbolMode::Exclude);
exports->methodTable()->getOwnPropertyNames(exports, globalObject, properties, DontEnumPropertiesMode::Exclude);
if (catchScope.exception()) {
catchScope.clearExceptionExceptTermination();
return;
}
for (auto property : properties) {
if (UNLIKELY(property.isEmpty() || property.isNull() || property == esModuleMarker || property.isPrivateName() || property.isSymbol()))
continue;
// ignore constructor
if (property == vm.propertyNames->constructor)
continue;
JSC::PropertySlot slot(exports, PropertySlot::InternalMethodType::Get);
if (!exports->getPropertySlot(globalObject, property, slot))
continue;
exportNames.append(property);
JSValue getterResult = slot.getValue(globalObject, property);
// If it throws, we keep them in the exports list, but mark it as undefined
// This is consistent with what Node.js does.
if (catchScope.exception()) {
catchScope.clearException();
getterResult = jsUndefined();
}
exportValues.append(getterResult);
needsToAssignDefault = needsToAssignDefault && property != vm.propertyNames->defaultKeyword;
}
}
} else if (canPerformFastEnumeration(structure)) {
exports->structure()->forEachProperty(vm, [&](const PropertyTableEntry& entry) -> bool {
auto key = entry.key();
if (key->isSymbol() || key == vm.propertyNames->defaultKeyword || entry.attributes() & PropertyAttribute::DontEnum)
if (key->isSymbol() || entry.attributes() & PropertyAttribute::DontEnum || key == vm.propertyNames->defaultKeyword)
return true;
exportNames.append(Identifier::fromUid(vm, key));
JSValue value = exports->getDirect(entry.offset());
exportNames.append(Identifier::fromUid(vm, key));
exportValues.append(value);
return true;
});
} else {
auto catchScope = DECLARE_CATCH_SCOPE(vm);
JSC::PropertyNameArray properties(vm, JSC::PropertyNameMode::Strings, JSC::PrivateSymbolMode::Exclude);
exports->methodTable()->getOwnPropertyNames(exports, globalObject, properties, DontEnumPropertiesMode::Exclude);
if (catchScope.exception()) {
@@ -624,11 +709,11 @@ void JSCommonJSModule::toSyntheticSource(JSC::JSGlobalObject* globalObject,
}
for (auto property : properties) {
if (UNLIKELY(property.isEmpty() || property.isNull() || property.isPrivateName() || property.isSymbol()))
if (UNLIKELY(property.isEmpty() || property.isNull() || property == vm.propertyNames->defaultKeyword || property.isPrivateName() || property.isSymbol()))
continue;
// ignore constructor
if (property == vm.propertyNames->constructor || property == vm.propertyNames->defaultKeyword)
if (property == vm.propertyNames->constructor)
continue;
JSC::PropertySlot slot(exports, PropertySlot::InternalMethodType::Get);
@@ -650,6 +735,11 @@ void JSCommonJSModule::toSyntheticSource(JSC::JSGlobalObject* globalObject,
}
}
}
if (needsToAssignDefault) {
exportNames.append(vm.propertyNames->defaultKeyword);
exportValues.append(result);
}
}
JSValue JSCommonJSModule::exportsObject()
@@ -759,6 +849,7 @@ bool JSCommonJSModule::evaluate(
{
auto& vm = globalObject->vm();
auto sourceProvider = Zig::SourceProvider::create(jsCast<Zig::GlobalObject*>(globalObject), source, JSC::SourceProviderSourceType::Program);
this->ignoreESModuleAnnotation = source.tag == ResolvedSourceTagPackageJSONTypeModule;
JSC::SourceCode rawInputSource(
WTFMove(sourceProvider));
@@ -766,6 +857,7 @@ bool JSCommonJSModule::evaluate(
return true;
this->sourceCode.set(vm, this, JSC::JSSourceCode::create(vm, WTFMove(rawInputSource)));
WTF::NakedPtr<JSC::Exception> exception;
evaluateCommonJSModuleOnce(vm, globalObject, this, this->m_dirname.get(), this->m_filename.get(), exception);
@@ -796,6 +888,7 @@ std::optional<JSC::SourceCode> createCommonJSModule(
JSValue entry = globalObject->requireMap()->get(globalObject, specifierValue);
auto sourceProvider = Zig::SourceProvider::create(jsCast<Zig::GlobalObject*>(globalObject), source, JSC::SourceProviderSourceType::Program);
bool ignoreESModuleAnnotation = source.tag == ResolvedSourceTagPackageJSONTypeModule;
SourceOrigin sourceOrigin = sourceProvider->sourceOrigin();
if (entry) {
@@ -827,6 +920,8 @@ std::optional<JSC::SourceCode> createCommonJSModule(
globalObject->requireMap()->set(globalObject, requireMapKey, moduleObject);
}
moduleObject->ignoreESModuleAnnotation = ignoreESModuleAnnotation;
return JSC::SourceCode(
JSC::SyntheticSourceProvider::create(
[](JSC::JSGlobalObject* lexicalGlobalObject,