Error when variable is circularly referenced in type annotation

Author: ahejlsberg

src/compiler/checker.ts

@@ -2278,12 +2278,19 @@ module ts {
                 }
             }
             else if (links.type === resolvingType) {
-                links.type = anyType;
-                if (compilerOptions.noImplicitAny) {
-                    let diagnostic = (<VariableLikeDeclaration>symbol.valueDeclaration).type ?
-                        Diagnostics._0_implicitly_has_type_any_because_it_is_referenced_directly_or_indirectly_in_its_own_type_annotation :
-                        Diagnostics._0_implicitly_has_type_any_because_it_is_does_not_have_a_type_annotation_and_is_referenced_directly_or_indirectly_in_its_own_initializer;
-                    error(symbol.valueDeclaration, diagnostic, symbolToString(symbol));
+                if ((<VariableLikeDeclaration>symbol.valueDeclaration).type) {
+                    // Variable has type annotation that circularly references the variable itself
+                    links.type = unknownType;
+                    error(symbol.valueDeclaration, Diagnostics._0_is_referenced_directly_or_indirectly_in_its_own_type_annotation,
+                        symbolToString(symbol));
+                }
+                else {
+                    // Variable has initializer that circularly references the variable itself
+                    links.type = anyType;
+                    if (compilerOptions.noImplicitAny) {
+                        error(symbol.valueDeclaration, Diagnostics._0_implicitly_has_type_any_because_it_is_does_not_have_a_type_annotation_and_is_referenced_directly_or_indirectly_in_its_own_initializer,
+                            symbolToString(symbol));
+                    }
                 }
             }
             return links.type;

src/compiler/diagnosticInformationMap.generated.ts

@@ -365,6 +365,7 @@ module ts {
         An_interface_can_only_extend_an_identifier_Slashqualified_name_with_optional_type_arguments: { code: 2499, category: DiagnosticCategory.Error, key: "An interface can only extend an identifier/qualified-name with optional type arguments." },
         A_class_can_only_implement_an_identifier_Slashqualified_name_with_optional_type_arguments: { code: 2500, category: DiagnosticCategory.Error, key: "A class can only implement an identifier/qualified-name with optional type arguments." },
         A_rest_element_cannot_contain_a_binding_pattern: { code: 2501, category: DiagnosticCategory.Error, key: "A rest element cannot contain a binding pattern." },
+        _0_is_referenced_directly_or_indirectly_in_its_own_type_annotation: { code: 2502, category: DiagnosticCategory.Error, key: "'{0}' is referenced directly or indirectly in its own type annotation." },
         Import_declaration_0_is_using_private_name_1: { code: 4000, category: DiagnosticCategory.Error, key: "Import declaration '{0}' is using private name '{1}'." },
         Type_parameter_0_of_exported_class_has_or_is_using_private_name_1: { code: 4002, category: DiagnosticCategory.Error, key: "Type parameter '{0}' of exported class has or is using private name '{1}'." },
         Type_parameter_0_of_exported_interface_has_or_is_using_private_name_1: { code: 4004, category: DiagnosticCategory.Error, key: "Type parameter '{0}' of exported interface has or is using private name '{1}'." },
@@ -516,7 +517,6 @@ module ts {
         Object_literal_s_property_0_implicitly_has_an_1_type: { code: 7018, category: DiagnosticCategory.Error, key: "Object literal's property '{0}' implicitly has an '{1}' type." },
         Rest_parameter_0_implicitly_has_an_any_type: { code: 7019, category: DiagnosticCategory.Error, key: "Rest parameter '{0}' implicitly has an 'any[]' type." },
         Call_signature_which_lacks_return_type_annotation_implicitly_has_an_any_return_type: { code: 7020, category: DiagnosticCategory.Error, key: "Call signature, which lacks return-type annotation, implicitly has an 'any' return type." },
-        _0_implicitly_has_type_any_because_it_is_referenced_directly_or_indirectly_in_its_own_type_annotation: { code: 7021, category: DiagnosticCategory.Error, key: "'{0}' implicitly has type 'any' because it is referenced directly or indirectly in its own type annotation." },
         _0_implicitly_has_type_any_because_it_is_does_not_have_a_type_annotation_and_is_referenced_directly_or_indirectly_in_its_own_initializer: { code: 7022, category: DiagnosticCategory.Error, key: "'{0}' implicitly has type 'any' because it is does not have a type annotation and is referenced directly or indirectly in its own initializer." },
         _0_implicitly_has_return_type_any_because_it_does_not_have_a_return_type_annotation_and_is_referenced_directly_or_indirectly_in_one_of_its_return_expressions: { code: 7023, category: DiagnosticCategory.Error, key: "'{0}' implicitly has return type 'any' because it does not have a return type annotation and is referenced directly or indirectly in one of its return expressions." },
         Function_implicitly_has_return_type_any_because_it_does_not_have_a_return_type_annotation_and_is_referenced_directly_or_indirectly_in_one_of_its_return_expressions: { code: 7024, category: DiagnosticCategory.Error, key: "Function implicitly has return type 'any' because it does not have a return type annotation and is referenced directly or indirectly in one of its return expressions." },

src/compiler/diagnosticMessages.json

@@ -1447,6 +1447,10 @@
         "category": "Error",
         "code": 2501
     },
+    "'{0}' is referenced directly or indirectly in its own type annotation.": {
+        "category": "Error",
+        "code": 2502
+    },
 
     "Import declaration '{0}' is using private name '{1}'.": {
         "category": "Error",
@@ -2055,10 +2059,6 @@
         "category": "Error",
         "code": 7020
     },
-    "'{0}' implicitly has type 'any' because it is referenced directly or indirectly in its own type annotation.": {
-        "category": "Error",
-        "code": 7021
-    },
     "'{0}' implicitly has type 'any' because it is does not have a type annotation and is referenced directly or indirectly in its own initializer.": {
         "category": "Error",
         "code": 7022