Disallow statements between overloads

src/compiler/checker.ts

@@ -4872,47 +4872,101 @@ module ts {
             var hasOverloads = false;
             var bodyDeclaration: FunctionDeclaration;
             var lastSeenNonAmbientDeclaration: FunctionDeclaration;
+            var previousDeclaration: FunctionDeclaration;
+
             var declarations = symbol.declarations;
             var isConstructor = (symbol.flags & SymbolFlags.Constructor) !== 0;
+
+            function reportImplementationExpectedError(node: FunctionDeclaration): void {
+                var seen = false;
+                var subsequentNode = forEachChild(node.parent, c => {
+                    if (seen) {
+                        return c;
+                    }
+                    else {
+                        seen = c === node;
+                    }
+                });
+                if (subsequentNode) {
+                    if (subsequentNode.kind === node.kind) {
+                        var errorNode: Node = (<FunctionDeclaration>subsequentNode).name || subsequentNode;
+                        if (node.name && (<FunctionDeclaration>subsequentNode).name && node.name.text === (<FunctionDeclaration>subsequentNode).name.text) {
+                            // the only situation when this is possible (same kind\same name but different symbol) - mixed static and instance class members
+                            Debug.assert(node.kind === SyntaxKind.Method);
+                            Debug.assert((node.flags & NodeFlags.Static) !== (subsequentNode.flags & NodeFlags.Static));
+                            var diagnostic = node.flags & NodeFlags.Static ? Diagnostics.Function_overload_must_be_static : Diagnostics.Function_overload_must_not_be_static;
+                            error(errorNode, diagnostic);
+                            return;
+                        }
+                        else if ((<FunctionDeclaration>subsequentNode).body) {
+                            error(errorNode, Diagnostics.Function_implementation_name_must_be_0, identifierToString(node.name));
+                            return;
+                        }
+                    }
+                }
+                var errorNode: Node = node.name || node;
+                if (isConstructor) {
+                    error(errorNode, Diagnostics.Constructor_implementation_is_missing);
+                }
+                else {
+                    error(errorNode, Diagnostics.Function_implementation_is_missing_or_not_immediately_following_the_declaration);
+                }
+            }
+
+            // when checking exported function declarations across modules check only duplicate implementations
+            // names and consistensy of modifiers are verified when we check local symbol
+            var isExportSymbolInsideModule = symbol.parent && symbol.parent.flags & SymbolFlags.Module;
             for (var i = 0; i < declarations.length; i++) {
                 var node = <FunctionDeclaration>declarations[i];
+                var inAmbientContext = isInAmbientContext(node);
+                var inAmbientContextOrInterface = node.parent.kind === SyntaxKind.InterfaceDeclaration || node.parent.kind === SyntaxKind.TypeLiteral || inAmbientContext;
+                if (inAmbientContextOrInterface) {
+                    // check if declarations are consecutive only if they are non-ambient
+                    // 1. ambient declarations can be interleaved
+                    // i.e. this is legal
+                    //     declare function foo();
+                    //     declare function bar();
+                    //     declare function foo();
+                    // 2. mixing ambient and non-ambient declarations is a separate error that will be reported - do not want to report an extra one
+                    previousDeclaration = undefined;
+                }
+
                 if (node.kind === SyntaxKind.FunctionDeclaration || node.kind === SyntaxKind.Method || node.kind === SyntaxKind.Constructor) {
                     var currentNodeFlags = getEffectiveDeclarationFlags(node, flagsToCheck);
                     someNodeFlags |= currentNodeFlags;
                     allNodeFlags &= currentNodeFlags;
 
-                    var inAmbientContext = isInAmbientContext(node);
-                    var inAmbientContextOrInterface = node.parent.kind === SyntaxKind.InterfaceDeclaration || node.parent.kind === SyntaxKind.TypeLiteral || inAmbientContext;
-                    if (!inAmbientContextOrInterface) {
-                        lastSeenNonAmbientDeclaration = node;
+                    if (node.body && bodyDeclaration) {
+                        if (isConstructor) {
+                            error(node, Diagnostics.Multiple_constructor_implementations_are_not_allowed);
+                        }
+                        else {
+                            error(node, Diagnostics.Duplicate_function_implementation);
+                        }
+                    }
+                    else if (!isExportSymbolInsideModule && previousDeclaration && previousDeclaration.parent === node.parent && previousDeclaration.end !== node.pos) {
+                        reportImplementationExpectedError(previousDeclaration);
                     }
 
                     if (node.body) {
-                        if (bodyDeclaration) {
-                            if (isConstructor) {
-                                error(node, Diagnostics.Multiple_constructor_implementations_are_not_allowed);
-                            }
-                            else {
-                                error(node, Diagnostics.Duplicate_function_implementation);
-                            }
-                        }
-                        else {
+                        if (!bodyDeclaration) {
                             bodyDeclaration = node;
                         }
                     }
                     else {
                         hasOverloads = true;
                     }
+
+                    previousDeclaration = node;
+
+                    if (!inAmbientContextOrInterface) {
+                        lastSeenNonAmbientDeclaration = node;
+                    }
                 }
             }
 
-            if (lastSeenNonAmbientDeclaration && !lastSeenNonAmbientDeclaration.body) {
-                if (isConstructor) {
-                    error(lastSeenNonAmbientDeclaration, Diagnostics.Constructor_implementation_expected);
-                }
-                else {
-                    error(lastSeenNonAmbientDeclaration, Diagnostics.Function_implementation_expected);
-                }
+            if (!isExportSymbolInsideModule && lastSeenNonAmbientDeclaration && !lastSeenNonAmbientDeclaration.body) {
+                reportImplementationExpectedError(lastSeenNonAmbientDeclaration);
             }
 
             if (hasOverloads) {
@@ -4985,7 +5039,7 @@ module ts {
                 }
             });
 
-            var commonDeclarationSpace = exportedDeclarationSpaces & nonExportedDeclarationSpaces
+            var commonDeclarationSpace = exportedDeclarationSpaces & nonExportedDeclarationSpaces;
 
             if (commonDeclarationSpace) {
                 // declaration spaces for exported and non-exported declarations intersect

src/compiler/diagnosticInformationMap.generated.ts

@@ -158,9 +158,12 @@ module ts {
         Duplicate_number_index_signature: { code: 2233, category: DiagnosticCategory.Error, key: "Duplicate number index signature." },
         All_declarations_of_an_interface_must_have_identical_type_parameters: { code: 2234, category: DiagnosticCategory.Error, key: "All declarations of an interface must have identical type parameters." },
         Expression_resolves_to_variable_declaration_i_that_compiler_uses_to_initialize_rest_parameter: { code: 2235, category: DiagnosticCategory.Error, key: "Expression resolves to variable declaration '_i' that compiler uses to initialize rest parameter." },
-        Constructor_implementation_expected: { code: 2240, category: DiagnosticCategory.Error, key: "Constructor implementation expected." },
+        Function_implementation_name_must_be_0: { code: 2239, category: DiagnosticCategory.Error, key: "Function implementation name must be '{0}'." },
+        Constructor_implementation_is_missing: { code: 2240, category: DiagnosticCategory.Error, key: "Constructor implementation is missing." },
         An_export_assignment_cannot_be_used_in_a_module_with_other_exported_elements: { code: 2245, category: DiagnosticCategory.Error, key: "An export assignment cannot be used in a module with other exported elements." },
         A_parameter_property_is_only_allowed_in_a_constructor_implementation: { code: 2246, category: DiagnosticCategory.Error, key: "A parameter property is only allowed in a constructor implementation." },
+        Function_overload_must_be_static: { code: 2247, category: DiagnosticCategory.Error, key: "Function overload must be static." },
+        Function_overload_must_not_be_static: { code: 2248, category: DiagnosticCategory.Error, key: "Function overload must not be static." },
         Circular_definition_of_import_alias_0: { code: 3000, category: DiagnosticCategory.Error, key: "Circular definition of import alias '{0}'." },
         Cannot_find_name_0: { code: 3001, category: DiagnosticCategory.Error, key: "Cannot find name '{0}'." },
         Module_0_has_no_exported_member_1: { code: 3002, category: DiagnosticCategory.Error, key: "Module '{0}' has no exported member '{1}'." },
@@ -276,7 +279,7 @@ module ts {
         Types_of_parameters_0_and_1_are_incompatible_Colon: { code: -9999999, category: DiagnosticCategory.Error, key: "Types of parameters '{0}' and '{1}' are incompatible:" },
         Unknown_identifier_0: { code: -9999999, category: DiagnosticCategory.Error, key: "Unknown identifier '{0}'." },
         Property_0_is_inaccessible: { code: -9999999, category: DiagnosticCategory.Error, key: "Property '{0}' is inaccessible." },
-        Function_implementation_expected: { code: -9999999, category: DiagnosticCategory.Error, key: "Function implementation expected." },
+        Function_implementation_is_missing_or_not_immediately_following_the_declaration: { code: -9999999, category: DiagnosticCategory.Error, key: "Function implementation is missing or not immediately following the declaration." },
         Property_0_of_type_1_is_not_assignable_to_string_index_type_2: { code: -9999999, category: DiagnosticCategory.Error, key: "Property '{0}' of type '{1}' is not assignable to string index type '{2}'." },
         Property_0_of_type_1_is_not_assignable_to_numeric_index_type_2: { code: -9999999, category: DiagnosticCategory.Error, key: "Property '{0}' of type '{1}' is not assignable to numeric index type '{2}'." },
         Numeric_index_type_0_is_not_assignable_to_string_index_type_1: { code: -9999999, category: DiagnosticCategory.Error, key: "Numeric index type '{0}' is not assignable to string index type '{1}'." },

src/compiler/diagnosticMessages.json

@@ -623,8 +623,12 @@
     "Expression resolves to variable declaration '_i' that compiler uses to initialize rest parameter.": {
         "category": "Error",
         "code": 2235
-	},
-    "Constructor implementation expected.": {
+    },
+    "Function implementation name must be '{0}'.": {
+        "category": "Error",
+        "code": 2239
+    },
+    "Constructor implementation is missing.": {
         "category": "Error",
         "code": 2240
     },
@@ -636,6 +640,14 @@
         "category": "Error",
         "code": 2246
     },
+    "Function overload must be static.": {
+        "category": "Error",
+        "code": 2247
+    },
+    "Function overload must not be static.": {
+        "category": "Error",
+        "code": 2248
+    },
     "Circular definition of import alias '{0}'.": {
         "category": "Error",
         "code": 3000
@@ -900,7 +912,6 @@
         "category": "Error",
         "code": 7020
     },
-
     "Variable declaration list cannot be empty.": {
         "category": "Error",
         "code": -9999999
@@ -1121,7 +1132,7 @@
         "category": "Error",
         "code": -9999999
     },
-    "Function implementation expected.": {
+    "Function implementation is missing or not immediately following the declaration.": {
         "category": "Error",
         "code": -9999999
     },

tests/baselines/reference/ClassDeclaration10.errors.txt

@@ -2,8 +2,8 @@
     class C {
        constructor();
        ~~~~~~~~~~~~~~
-!!! Constructor implementation expected.
+!!! Constructor implementation is missing.
        foo();
-       ~~~~~~
-!!! Function implementation expected.
+       ~~~
+!!! Function implementation is missing or not immediately following the declaration.
     }

tests/baselines/reference/ClassDeclaration11.errors.txt

@@ -2,6 +2,6 @@
     class C {
        constructor();
        ~~~~~~~~~~~~~~
-!!! Constructor implementation expected.
+!!! Constructor implementation is missing.
        foo() { }
     }

tests/baselines/reference/ClassDeclaration13.errors.txt

@@ -1,7 +1,7 @@
 ==== tests/cases/compiler/ClassDeclaration13.ts (1 errors) ====
     class C {
        foo();
-       ~~~~~~
-!!! Function implementation expected.
        bar() { }
+       ~~~
+!!! Function implementation name must be 'foo'.
     }

tests/baselines/reference/ClassDeclaration14.errors.txt

@@ -1,9 +1,9 @@
 ==== tests/cases/compiler/ClassDeclaration14.ts (2 errors) ====
     class C {
        foo();
-       ~~~~~~
-!!! Function implementation expected.
+       ~~~
+!!! Function implementation is missing or not immediately following the declaration.
        constructor();
        ~~~~~~~~~~~~~~
-!!! Constructor implementation expected.
+!!! Constructor implementation is missing.
     }

tests/baselines/reference/ClassDeclaration15.errors.txt

@@ -1,7 +1,7 @@
 ==== tests/cases/compiler/ClassDeclaration15.ts (1 errors) ====
     class C {
        foo();
-       ~~~~~~
-!!! Function implementation expected.
+       ~~~
+!!! Function implementation is missing or not immediately following the declaration.
        constructor() { }
     }

tests/baselines/reference/ClassDeclaration21.errors.txt

@@ -1,7 +1,7 @@
 ==== tests/cases/compiler/ClassDeclaration21.ts (1 errors) ====
     class C {
         0();
-        ~~~~
-!!! Function implementation expected.
         1() { }
+        ~
+!!! Function implementation name must be '0'.
     }

tests/baselines/reference/ClassDeclaration22.errors.txt

@@ -1,7 +1,7 @@
 ==== tests/cases/compiler/ClassDeclaration22.ts (1 errors) ====
     class C {
         "foo"();
-        ~~~~~~~~
-!!! Function implementation expected.
         "bar"() { }
+        ~~~~~
+!!! Function implementation name must be '"foo"'.
     }

tests/baselines/reference/ClassDeclaration25.errors.txt

@@ -5,10 +5,10 @@
     }
     class List<U> implements IList<U> {
         data(): U;
-        ~~~~~~~~~~
-!!! Function implementation expected.
+        ~~~~
+!!! Function implementation is missing or not immediately following the declaration.
         next(): string;
-        ~~~~~~~~~~~~~~~
-!!! Function implementation expected.
+        ~~~~
+!!! Function implementation is missing or not immediately following the declaration.
     }
 

tests/baselines/reference/ClassDeclaration8.errors.txt

@@ -2,5 +2,5 @@
     class C {
       constructor();
       ~~~~~~~~~~~~~~
-!!! Constructor implementation expected.
+!!! Constructor implementation is missing.
     }

tests/baselines/reference/ClassDeclaration9.errors.txt

@@ -1,6 +1,6 @@
 ==== tests/cases/compiler/ClassDeclaration9.ts (1 errors) ====
     class C {
        foo();
-       ~~~~~~
-!!! Function implementation expected.
+       ~~~
+!!! Function implementation is missing or not immediately following the declaration.
     }

tests/baselines/reference/FunctionDeclaration3.errors.txt

@@ -1,4 +1,4 @@
 ==== tests/cases/compiler/FunctionDeclaration3.ts (1 errors) ====
     function foo();
-    ~~~~~~~~~~~~~~~
-!!! Function implementation expected.
+             ~~~
+!!! Function implementation is missing or not immediately following the declaration.

tests/baselines/reference/FunctionDeclaration4.errors.txt

@@ -1,5 +1,5 @@
 ==== tests/cases/compiler/FunctionDeclaration4.ts (1 errors) ====
     function foo();
-    ~~~~~~~~~~~~~~~
-!!! Function implementation expected.
-    function bar() { }
+    function bar() { }
+             ~~~
+!!! Function implementation name must be 'foo'.

tests/baselines/reference/FunctionDeclaration6.errors.txt

@@ -1,7 +1,7 @@
 ==== tests/cases/compiler/FunctionDeclaration6.ts (1 errors) ====
     {
         function foo();
-        ~~~~~~~~~~~~~~~
-!!! Function implementation expected.
         function bar() { }
+                 ~~~
+!!! Function implementation name must be 'foo'.
     }

tests/baselines/reference/FunctionDeclaration7.errors.txt

@@ -1,6 +1,6 @@
 ==== tests/cases/compiler/FunctionDeclaration7.ts (1 errors) ====
     module M {
        function foo();
-       ~~~~~~~~~~~~~~~
-!!! Function implementation expected.
+                ~~~
+!!! Function implementation is missing or not immediately following the declaration.
     }

tests/baselines/reference/assignmentCompatFunctionsWithOptionalArgs.errors.txt

@@ -1,7 +1,7 @@
 ==== tests/cases/compiler/assignmentCompatFunctionsWithOptionalArgs.ts (3 errors) ====
     function foo(x: { id: number; name?: string; }): void;
-    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-!!! Function implementation expected.
+             ~~~
+!!! Function implementation is missing or not immediately following the declaration.
     foo({ id: 1234 });                 // Ok
     foo({ id: 1234, name: "hello" });  // Ok
     foo({ id: 1234, name: false });    // Error, name of wrong type

tests/baselines/reference/callOverloads1.errors.txt

@@ -8,8 +8,8 @@
     }
 
     function Foo(); // error
-    ~~~~~~~~~~~~~~~
-!!! Function implementation expected.
+             ~~~
+!!! Function implementation is missing or not immediately following the declaration.
              ~~~
 !!! Duplicate identifier 'Foo'.
     function F1(s:string);