Merge pull request #2335 from Microsoft/es6ImportExportEmit

ES6 emit for new import / export syntax

Author: mhegazy

scripts/processDiagnosticMessages.ts

@@ -65,8 +65,7 @@ function buildInfoFileOutput(messageTable: InputDiagnosticMessageTable, nameMap:
         '        ' + convertPropertyName(nameMap[name]) +
         ': { code: ' + diagnosticDetails.code +
         ', category: DiagnosticCategory.' + diagnosticDetails.category +
-        ', key: "' + name.replace('"', '\\"') + '"' +
-        (diagnosticDetails.isEarly ? ', isEarly: true' : '') +
+        ', key: "' + name.replace(/[\"]/g, '\\"') + '"' +
         ' },\r\n';
     }
 

src/compiler/checker.ts

@@ -783,7 +783,7 @@ module ts {
         }
 
         function getExportsForModule(moduleSymbol: Symbol): SymbolTable {
-            if (compilerOptions.target < ScriptTarget.ES6) {
+            if (languageVersion < ScriptTarget.ES6) {
                 // A default export hides all other exports in CommonJS and AMD modules
                 let defaultSymbol = getExportAssignmentSymbol(moduleSymbol);
                 if (defaultSymbol) {
@@ -1812,6 +1812,11 @@ module ts {
                     case SyntaxKind.ParenthesizedType:
                         return isDeclarationVisible(<Declaration>node.parent);
 
+                    case SyntaxKind.ImportClause:
+                    case SyntaxKind.NamespaceImport:
+                    case SyntaxKind.ImportSpecifier:
+                        return false;
+
                     // Type parameters are always visible
                     case SyntaxKind.TypeParameter:
                     // Source file is always visible
@@ -10093,6 +10098,12 @@ module ts {
                         }
                     }
                 }
+                else {
+                    if (languageVersion >= ScriptTarget.ES6) {
+                        // Import equals declaration is deprecated in es6 or above
+                        grammarErrorOnNode(node, Diagnostics.Import_assignment_cannot_be_used_when_targeting_ECMAScript_6_or_higher_Consider_using_import_Asterisk_as_ns_from_mod_import_a_from_mod_or_import_d_from_mod_instead);
+                    }
+                }
             }
         }
 
@@ -10140,6 +10151,11 @@ module ts {
             }
 
             checkExternalModuleExports(container);
+
+            if (node.isExportEquals && languageVersion >= ScriptTarget.ES6) {
+                // export assignment is deprecated in es6 or above
+                grammarErrorOnNode(node, Diagnostics.Export_assignment_cannot_be_used_when_targeting_ECMAScript_6_or_higher_Consider_using_export_default_instead);
+            }
         }
 
         function getModuleStatements(node: Declaration): ModuleElement[] {
@@ -10182,7 +10198,7 @@ module ts {
             if (!links.exportsChecked) {
                 let defaultSymbol = getExportAssignmentSymbol(moduleSymbol);
                 if (defaultSymbol) {
-                    if (hasExportedMembers(moduleSymbol)) {
+                    if (languageVersion < ScriptTarget.ES6 && hasExportedMembers(moduleSymbol)) {
                         let declaration = getDeclarationOfAliasSymbol(defaultSymbol) || defaultSymbol.valueDeclaration;
                         error(declaration, Diagnostics.An_export_assignment_cannot_be_used_in_a_module_with_other_exported_elements);
                     }
@@ -11005,7 +11021,15 @@ module ts {
 
         function getExportNameSubstitution(symbol: Symbol, location: Node): string {
             if (isExternalModuleSymbol(symbol.parent)) {
-                return "exports." + unescapeIdentifier(symbol.name);
+                var symbolName = unescapeIdentifier(symbol.name);
+                // If this is es6 or higher, just use the name of the export
+                // no need to qualify it.
+                if (languageVersion >= ScriptTarget.ES6) {
+                    return symbolName;
+                }
+                else {
+                    return "exports." + symbolName;
+                }
             }
             let node = location;
             let containerSymbol = getParentOfSymbol(symbol);
@@ -11033,7 +11057,7 @@ module ts {
                     return getExportNameSubstitution(exportSymbol, node.parent);
                 }
                 // Named imports from ES6 import declarations are rewritten
-                if (symbol.flags & SymbolFlags.Alias) {
+                if (symbol.flags & SymbolFlags.Alias && languageVersion < ScriptTarget.ES6) {
                     return getAliasNameSubstitution(symbol);
                 }
             }
@@ -11069,7 +11093,6 @@ module ts {
                     return true;
                 }
             }
-            return forEachChild(node, isReferencedAliasDeclaration);
         }
 
         function isImplementationOfOverload(node: FunctionLikeDeclaration) {

src/compiler/diagnosticInformationMap.generated.ts

@@ -159,6 +159,9 @@ module ts {
         Unterminated_Unicode_escape_sequence: { code: 1199, category: DiagnosticCategory.Error, key: "Unterminated Unicode escape sequence." },
         Line_terminator_not_permitted_before_arrow: { code: 1200, category: DiagnosticCategory.Error, key: "Line terminator not permitted before arrow." },
         A_type_annotation_on_an_export_statement_is_only_allowed_in_an_ambient_external_module_declaration: { code: 1201, category: DiagnosticCategory.Error, key: "A type annotation on an export statement is only allowed in an ambient external module declaration." },
+        Import_assignment_cannot_be_used_when_targeting_ECMAScript_6_or_higher_Consider_using_import_Asterisk_as_ns_from_mod_import_a_from_mod_or_import_d_from_mod_instead: { code: 1202, category: DiagnosticCategory.Error, key: "Import assignment cannot be used when targeting ECMAScript 6 or higher. Consider using 'import * as ns from \"mod\"', 'import {a} from \"mod\"' or 'import d from \"mod\"' instead." },
+        Export_assignment_cannot_be_used_when_targeting_ECMAScript_6_or_higher_Consider_using_export_default_instead: { code: 1203, category: DiagnosticCategory.Error, key: "Export assignment cannot be used when targeting ECMAScript 6 or higher. Consider using 'export default' instead." },
+        Cannot_compile_external_modules_into_amd_or_commonjs_when_targeting_es6_or_higher: { code: 1204, category: DiagnosticCategory.Error, key: "Cannot compile external modules into amd or commonjs when targeting es6 or higher." },
         Duplicate_identifier_0: { code: 2300, category: DiagnosticCategory.Error, key: "Duplicate identifier '{0}'." },
         Initializer_of_instance_member_variable_0_cannot_reference_identifier_1_declared_in_the_constructor: { code: 2301, category: DiagnosticCategory.Error, key: "Initializer of instance member variable '{0}' cannot reference identifier '{1}' declared in the constructor." },
         Static_members_cannot_reference_class_type_parameters: { code: 2302, category: DiagnosticCategory.Error, key: "Static members cannot reference class type parameters." },

src/compiler/diagnosticMessages.json

@@ -627,6 +627,18 @@
         "category": "Error",
         "code": 1201
     },
+    "Import assignment cannot be used when targeting ECMAScript 6 or higher. Consider using 'import * as ns from \"mod\"', 'import {a} from \"mod\"' or 'import d from \"mod\"' instead.": {
+        "category": "Error",
+        "code": 1202
+    },
+    "Export assignment cannot be used when targeting ECMAScript 6 or higher. Consider using 'export default' instead.": {
+        "category": "Error",
+        "code": 1203
+    },
+    "Cannot compile external modules into amd or commonjs when targeting es6 or higher.": {
+        "category": "Error",
+        "code": 1204
+    },
 
     "Duplicate identifier '{0}'.": {
         "category": "Error",