1 files changed, 328 insertions, 0 deletions
diff --git a/js/src/builtin/Module.js b/js/src/builtin/Module.js
new file mode 100644
index 000000000..7b70a7fe8
--- /dev/null
+++ b/js/src/builtin/Module.js
@@ -0,0 +1,328 @@
+/* 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/. */
+
+function CallModuleResolveHook(module, specifier, expectedMinimumState)
+{
+    let requestedModule = HostResolveImportedModule(module, specifier);
+    if (requestedModule.state < expectedMinimumState)
+        ThrowInternalError(JSMSG_BAD_MODULE_STATE);
+
+    return requestedModule;
+}
+
+// 15.2.1.16.2 GetExportedNames(exportStarSet)
+function ModuleGetExportedNames(exportStarSet = [])
+{
+    if (!IsObject(this) || !IsModule(this)) {
+        return callFunction(CallModuleMethodIfWrapped, this, exportStarSet,
+                            "ModuleGetExportedNames");
+    }
+
+    // Step 1
+    let module = this;
+
+    // Step 2
+    if (callFunction(ArrayIncludes, exportStarSet, module))
+        return [];
+
+    // Step 3
+    _DefineDataProperty(exportStarSet, exportStarSet.length, module);
+
+    // Step 4
+    let exportedNames = [];
+    let namesCount = 0;
+
+    // Step 5
+    let localExportEntries = module.localExportEntries;
+    for (let i = 0; i < localExportEntries.length; i++) {
+        let e = localExportEntries[i];
+        _DefineDataProperty(exportedNames, namesCount++, e.exportName);
+    }
+
+    // Step 6
+    let indirectExportEntries = module.indirectExportEntries;
+    for (let i = 0; i < indirectExportEntries.length; i++) {
+        let e = indirectExportEntries[i];
+        _DefineDataProperty(exportedNames, namesCount++, e.exportName);
+    }
+
+    // Step 7
+    let starExportEntries = module.starExportEntries;
+    for (let i = 0; i < starExportEntries.length; i++) {
+        let e = starExportEntries[i];
+        let requestedModule = CallModuleResolveHook(module, e.moduleRequest,
+                                                    MODULE_STATE_INSTANTIATED);
+        let starNames = callFunction(requestedModule.getExportedNames, requestedModule,
+                                     exportStarSet);
+        for (let j = 0; j < starNames.length; j++) {
+            let n = starNames[j];
+            if (n !== "default" && !callFunction(ArrayIncludes, exportedNames, n))
+                _DefineDataProperty(exportedNames, namesCount++, n);
+        }
+    }
+
+    return exportedNames;
+}
+
+// 15.2.1.16.3 ResolveExport(exportName, resolveSet, exportStarSet)
+function ModuleResolveExport(exportName, resolveSet = [], exportStarSet = [])
+{
+    if (!IsObject(this) || !IsModule(this)) {
+        return callFunction(CallModuleMethodIfWrapped, this, exportName, resolveSet,
+                            exportStarSet, "ModuleResolveExport");
+    }
+
+    // Step 1
+    let module = this;
+
+    // Step 2
+    for (let i = 0; i < resolveSet.length; i++) {
+        let r = resolveSet[i];
+        if (r.module === module && r.exportName === exportName)
+            return null;
+    }
+
+    // Step 3
+    _DefineDataProperty(resolveSet, resolveSet.length, {module: module, exportName: exportName});
+
+    // Step 4
+    let localExportEntries = module.localExportEntries;
+    for (let i = 0; i < localExportEntries.length; i++) {
+        let e = localExportEntries[i];
+        if (exportName === e.exportName)
+            return {module: module, bindingName: e.localName};
+    }
+
+    // Step 5
+    let indirectExportEntries = module.indirectExportEntries;
+    for (let i = 0; i < indirectExportEntries.length; i++) {
+        let e = indirectExportEntries[i];
+        if (exportName === e.exportName) {
+            let importedModule = CallModuleResolveHook(module, e.moduleRequest,
+                                                       MODULE_STATE_INSTANTIATED);
+            let indirectResolution = callFunction(importedModule.resolveExport, importedModule,
+                                                  e.importName, resolveSet, exportStarSet);
+            if (indirectResolution !== null)
+                return indirectResolution;
+        }
+    }
+
+    // Step 6
+    if (exportName === "default") {
+        // A default export cannot be provided by an export *.
+        ThrowSyntaxError(JSMSG_BAD_DEFAULT_EXPORT);
+    }
+
+    // Step 7
+    if (callFunction(ArrayIncludes, exportStarSet, module))
+        return null;
+
+    // Step 8
+    _DefineDataProperty(exportStarSet, exportStarSet.length, module);
+
+    // Step 9
+    let starResolution = null;
+
+    // Step 10
+    let starExportEntries = module.starExportEntries;
+    for (let i = 0; i < starExportEntries.length; i++) {
+        let e = starExportEntries[i];
+        let importedModule = CallModuleResolveHook(module, e.moduleRequest,
+                                                   MODULE_STATE_INSTANTIATED);
+        let resolution = callFunction(importedModule.resolveExport, importedModule,
+                                      exportName, resolveSet, exportStarSet);
+        if (resolution === "ambiguous")
+            return resolution;
+
+        if (resolution !== null) {
+            if (starResolution === null) {
+                starResolution = resolution;
+            } else {
+                if (resolution.module !== starResolution.module ||
+                    resolution.exportName !== starResolution.exportName)
+                {
+                    return "ambiguous";
+                }
+            }
+        }
+    }
+
+    return starResolution;
+}
+
+// 15.2.1.18 GetModuleNamespace(module)
+function GetModuleNamespace(module)
+{
+    // Step 2
+    let namespace = module.namespace;
+
+    // Step 3
+    if (typeof namespace === "undefined") {
+        let exportedNames = callFunction(module.getExportedNames, module);
+        let unambiguousNames = [];
+        for (let i = 0; i < exportedNames.length; i++) {
+            let name = exportedNames[i];
+            let resolution = callFunction(module.resolveExport, module, name);
+            if (resolution === null)
+                ThrowSyntaxError(JSMSG_MISSING_NAMESPACE_EXPORT);
+            if (resolution !== "ambiguous")
+                _DefineDataProperty(unambiguousNames, unambiguousNames.length, name);
+        }
+        namespace = ModuleNamespaceCreate(module, unambiguousNames);
+    }
+
+    // Step 4
+    return namespace;
+}
+
+// 9.4.6.13 ModuleNamespaceCreate(module, exports)
+function ModuleNamespaceCreate(module, exports)
+{
+    callFunction(std_Array_sort, exports);
+
+    let ns = NewModuleNamespace(module, exports);
+
+    // Pre-compute all bindings now rather than calling ResolveExport() on every
+    // access.
+    for (let i = 0; i < exports.length; i++) {
+        let name = exports[i];
+        let binding = callFunction(module.resolveExport, module, name);
+        assert(binding !== null && binding !== "ambiguous", "Failed to resolve binding");
+        AddModuleNamespaceBinding(ns, name, binding.module, binding.bindingName);
+    }
+
+    return ns;
+}
+
+function GetModuleEnvironment(module)
+{
+    assert(IsModule(module), "Non-module passed to GetModuleEnvironment");
+
+    // Check for a previous failed attempt to instantiate this module. This can
+    // only happen due to a bug in the module loader.
+    if (module.state == MODULE_STATE_FAILED)
+        ThrowInternalError(JSMSG_MODULE_INSTANTIATE_FAILED);
+
+    let env = UnsafeGetReservedSlot(module, MODULE_OBJECT_ENVIRONMENT_SLOT);
+    assert(env === undefined || IsModuleEnvironment(env),
+           "Module environment slot contains unexpected value");
+
+    return env;
+}
+
+function RecordInstantationFailure(module)
+{
+    // Set the module's environment slot to 'null' to indicate a failed module
+    // instantiation.
+    assert(IsModule(module), "Non-module passed to RecordInstantationFailure");
+    SetModuleState(module, MODULE_STATE_FAILED);
+    UnsafeSetReservedSlot(module, MODULE_OBJECT_ENVIRONMENT_SLOT, undefined);
+}
+
+// 15.2.1.16.4 ModuleDeclarationInstantiation()
+function ModuleDeclarationInstantiation()
+{
+    if (!IsObject(this) || !IsModule(this))
+        return callFunction(CallModuleMethodIfWrapped, this, "ModuleDeclarationInstantiation");
+
+    // Step 1
+    let module = this;
+
+    // Step 5
+    if (GetModuleEnvironment(module) !== undefined)
+        return;
+
+    // Step 7
+    CreateModuleEnvironment(module);
+    let env = GetModuleEnvironment(module);
+
+    SetModuleState(this, MODULE_STATE_INSTANTIATED);
+
+    try {
+        // Step 8
+        let requestedModules = module.requestedModules;
+        for (let i = 0; i < requestedModules.length; i++) {
+            let required = requestedModules[i];
+            let requiredModule = CallModuleResolveHook(module, required, MODULE_STATE_PARSED);
+            callFunction(requiredModule.declarationInstantiation, requiredModule);
+        }
+
+        // Step 9
+        let indirectExportEntries = module.indirectExportEntries;
+        for (let i = 0; i < indirectExportEntries.length; i++) {
+            let e = indirectExportEntries[i];
+            let resolution = callFunction(module.resolveExport, module, e.exportName);
+            if (resolution === null)
+                ThrowSyntaxError(JSMSG_MISSING_INDIRECT_EXPORT, e.exportName);
+            if (resolution === "ambiguous")
+                ThrowSyntaxError(JSMSG_AMBIGUOUS_INDIRECT_EXPORT, e.exportName);
+        }
+
+        // Step 12
+        let importEntries = module.importEntries;
+        for (let i = 0; i < importEntries.length; i++) {
+            let imp = importEntries[i];
+            let importedModule = CallModuleResolveHook(module, imp.moduleRequest,
+                                                       MODULE_STATE_INSTANTIATED);
+            if (imp.importName === "*") {
+                let namespace = GetModuleNamespace(importedModule);
+                CreateNamespaceBinding(env, imp.localName, namespace);
+            } else {
+                let resolution = callFunction(importedModule.resolveExport, importedModule,
+                                              imp.importName);
+                if (resolution === null)
+                    ThrowSyntaxError(JSMSG_MISSING_IMPORT, imp.importName);
+                if (resolution === "ambiguous")
+                    ThrowSyntaxError(JSMSG_AMBIGUOUS_IMPORT, imp.importName);
+                CreateImportBinding(env, imp.localName, resolution.module, resolution.bindingName);
+            }
+        }
+
+        // Step 16.iv
+        InstantiateModuleFunctionDeclarations(module);
+    } catch (e) {
+        RecordInstantationFailure(module);
+        throw e;
+    }
+}
+_SetCanonicalName(ModuleDeclarationInstantiation, "ModuleDeclarationInstantiation");
+
+// 15.2.1.16.5 ModuleEvaluation()
+function ModuleEvaluation()
+{
+    if (!IsObject(this) || !IsModule(this))
+        return callFunction(CallModuleMethodIfWrapped, this, "ModuleEvaluation");
+
+    // Step 1
+    let module = this;
+
+    if (module.state < MODULE_STATE_INSTANTIATED)
+        ThrowInternalError(JSMSG_BAD_MODULE_STATE);
+
+    // Step 4
+    if (module.state == MODULE_STATE_EVALUATED)
+        return undefined;
+
+    // Step 5
+    SetModuleState(this, MODULE_STATE_EVALUATED);
+
+    // Step 6
+    let requestedModules = module.requestedModules;
+    for (let i = 0; i < requestedModules.length; i++) {
+        let required = requestedModules[i];
+        let requiredModule = CallModuleResolveHook(module, required, MODULE_STATE_INSTANTIATED);
+        callFunction(requiredModule.evaluation, requiredModule);
+    }
+
+    return EvaluateModule(module);
+}
+_SetCanonicalName(ModuleEvaluation, "ModuleEvaluation");
+
+function ModuleNamespaceEnumerate()
+{
+    if (!IsObject(this) || !IsModuleNamespace(this))
+        return callFunction(CallModuleMethodIfWrapped, this, "ModuleNamespaceEnumerate");
+
+    return CreateListIterator(ModuleNamespaceExports(this));
+}