Report error on export assignment with es6 and above target

Conflicts:
	src/compiler/checker.ts
	tests/baselines/reference/es6ImportDefaultBinding.errors.txt
	tests/baselines/reference/es6ImportDefaultBindingFollowedWithNamedImport1.errors.txt
	tests/baselines/reference/es6ImportDefaultBindingMergeErrors.errors.txt
	tests/baselines/reference/es6ImportEqualsDeclaration.errors.txt
	tests/cases/compiler/es6ImportNameSpaceImportMergeErrors.ts
	tests/cases/compiler/es6ImportNameSpaceImportNoNamedExports.ts
	tests/cases/compiler/es6ImportNamedImportInExportAssignment.ts
	tests/cases/compiler/es6ImportNamedImportInIndirectExportAssignment.ts
	tests/cases/compiler/es6ImportNamedImportNoNamedExports.ts

src/compiler/checker.ts

@@ -9940,6 +9940,11 @@ module ts {
                 checkExpressionCached(node.expression);
             }
             checkExternalModuleExports(container);
+
+            if (compilerOptions.target >= 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[] {

src/compiler/diagnosticInformationMap.generated.ts

@@ -158,6 +158,7 @@ module ts {
         An_extended_Unicode_escape_value_must_be_between_0x0_and_0x10FFFF_inclusive: { code: 1198, category: DiagnosticCategory.Error, key: "An extended Unicode escape value must be between 0x0 and 0x10FFFF inclusive." },
         Unterminated_Unicode_escape_sequence: { code: 1199, category: DiagnosticCategory.Error, key: "Unterminated Unicode escape sequence." },
         Import_assignment_cannot_be_used_when_targeting_ECMAScript_6_or_higher_Consider_using_import_Asterisk_from_mod_import_a_from_mod_or_import_d_from_mod_instead: { code: 1200, category: DiagnosticCategory.Error, key: "Import assignment cannot be used when targeting ECMAScript 6 or higher. Consider using 'import * 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: 1201, category: DiagnosticCategory.Error, key: "Export assignment cannot be used when targeting ECMAScript 6 or higher. Consider using 'export default' instead." },
         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

@@ -623,6 +623,10 @@
         "category": "Error",
         "code": 1200
     },
+    "Export assignment cannot be used when targeting ECMAScript 6 or higher. Consider using 'export default' instead.": {
+        "category": "Error",
+        "code": 1201
+    },
 
     "Duplicate identifier '{0}'.": {
         "category": "Error",

tests/baselines/reference/es6ExportAssignment.errors.txt

@@ -0,0 +1,12 @@
+tests/cases/compiler/es6ExportAssignment.ts(3,1): error TS1148: Cannot compile external modules unless the '--module' flag is provided.
+tests/cases/compiler/es6ExportAssignment.ts(3,1): error TS1201: Export assignment cannot be used when targeting ECMAScript 6 or higher. Consider using 'export default' instead.
+
+
+==== tests/cases/compiler/es6ExportAssignment.ts (2 errors) ====
+    
+    var a = 10;
+    export = a;
+    ~~~~~~~~~~~
+!!! error TS1148: Cannot compile external modules unless the '--module' flag is provided.
+    ~~~~~~~~~~~
+!!! error TS1201: Export assignment cannot be used when targeting ECMAScript 6 or higher. Consider using 'export default' instead.

tests/baselines/reference/es6ExportAssignment.js

@@ -0,0 +1,8 @@
+//// [es6ExportAssignment.ts]
+
+var a = 10;
+export = a;
+
+//// [es6ExportAssignment.js]
+var a = 10;
+module.exports = a;

tests/baselines/reference/es6ImportEqualsDeclaration.errors.txt

@@ -1,15 +1,18 @@
 tests/cases/compiler/client.ts(1,1): error TS1200: Import assignment cannot be used when targeting ECMAScript 6 or higher. Consider using 'import * from "mod"', 'import {a} from "mod"' or 'import d from "mod"' instead.
 tests/cases/compiler/server.ts(3,1): error TS1148: Cannot compile external modules unless the '--module' flag is provided.
+tests/cases/compiler/server.ts(3,1): error TS1201: Export assignment cannot be used when targeting ECMAScript 6 or higher. Consider using 'export default' instead.
 
 
 ==== tests/cases/compiler/client.ts (1 errors) ====
     import a = require("server");
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 !!! error TS1200: Import assignment cannot be used when targeting ECMAScript 6 or higher. Consider using 'import * from "mod"', 'import {a} from "mod"' or 'import d from "mod"' instead.
-==== tests/cases/compiler/server.ts (1 errors) ====
+==== tests/cases/compiler/server.ts (2 errors) ====
     
     var a = 10;
     export = a;
     ~~~~~~~~~~~
 !!! error TS1148: Cannot compile external modules unless the '--module' flag is provided.
+    ~~~~~~~~~~~
+!!! error TS1201: Export assignment cannot be used when targeting ECMAScript 6 or higher. Consider using 'export default' instead.
     

tests/cases/compiler/es6ExportAssignment.ts

@@ -0,0 +1,4 @@
+// @target: es6
+
+var a = 10;
+export = a;