basic support for declaring properties on funcitons

src/compiler/binder.ts

@@ -265,6 +265,7 @@ namespace ts {
                             return "export=";
                         case SpecialPropertyAssignmentKind.ExportsProperty:
                         case SpecialPropertyAssignmentKind.ThisProperty:
+                        case SpecialPropertyAssignmentKind.Property:
                             // exports.x = ... or this.y = ...
                             return ((node as BinaryExpression).left as PropertyAccessExpression).name.text;
                         case SpecialPropertyAssignmentKind.PrototypeProperty:
@@ -1921,6 +1922,9 @@ namespace ts {
                             case SpecialPropertyAssignmentKind.ThisProperty:
                                 bindThisPropertyAssignment(<BinaryExpression>node);
                                 break;
+                            case SpecialPropertyAssignmentKind.Property:
+                                bindPropertyAssignment(<BinaryExpression>node);
+                                break;
                             case SpecialPropertyAssignmentKind.None:
                                 // Nothing to do
                                 break;
@@ -2225,6 +2229,32 @@ namespace ts {
             declareSymbol(funcSymbol.members, funcSymbol, leftSideOfAssignment, SymbolFlags.Property, SymbolFlags.PropertyExcludes);
         }
 
+        function bindPropertyAssignment(node: BinaryExpression) {
+            // We saw a node of the form 'x.y = z'. Declare a 'member' y on x if x was a function.
+
+            // Look up the function in the local scope, since prototype assignments should
+            // follow the function declaration
+            const leftSideOfAssignment = node.left as PropertyAccessExpression;
+            const target = leftSideOfAssignment.expression as Identifier;
+
+            // Fix up parent pointers since we're going to use these nodes before we bind into them
+            leftSideOfAssignment.parent = node;
+            target.parent = leftSideOfAssignment;
+
+            const funcSymbol = container.locals[target.text];
+            if (!funcSymbol || !(funcSymbol.flags & SymbolFlags.Function || isDeclarationOfFunctionExpression(funcSymbol))) {
+                return;
+            }
+
+            // Set up the members collection if it doesn't exist already
+            if (!funcSymbol.exports) {
+                funcSymbol.exports = createMap<Symbol>();
+            }
+
+            // Declare the method/property
+            declareSymbol(funcSymbol.exports, funcSymbol, leftSideOfAssignment, SymbolFlags.Property, SymbolFlags.PropertyExcludes);
+        }
+
         function bindCallExpression(node: CallExpression) {
             // We're only inspecting call expressions to detect CommonJS modules, so we can skip
             // this check if we've already seen the module indicator

src/compiler/checker.ts

@@ -4580,7 +4580,7 @@ namespace ts {
                 // Combinations of function, class, enum and module
                 let members = emptySymbols;
                 let constructSignatures: Signature[] = emptyArray;
-                if (symbol.flags & SymbolFlags.HasExports) {
+                if (symbol.exports) {
                     members = getExportsOfSymbol(symbol);
                 }
                 if (symbol.flags & SymbolFlags.Class) {
@@ -19871,22 +19871,29 @@ namespace ts {
             return getLeftSideOfImportEqualsOrExportAssignment(node) !== undefined;
         }
 
+        function getSpecialPropertyAssignmentSymbolFromEntityName(entityName: EntityName | PropertyAccessExpression) {
+            const specialPropertyAssignmentKind = getSpecialPropertyAssignmentKind(entityName.parent.parent);
+            switch (specialPropertyAssignmentKind) {
+                case SpecialPropertyAssignmentKind.ExportsProperty:
+                case SpecialPropertyAssignmentKind.PrototypeProperty:
+                    return getSymbolOfNode(entityName.parent);
+                case SpecialPropertyAssignmentKind.ThisProperty:
+                case SpecialPropertyAssignmentKind.ModuleExports:
+                case SpecialPropertyAssignmentKind.Property:
+                    return getSymbolOfNode(entityName.parent.parent);
+            }
+        }
+
         function getSymbolOfEntityNameOrPropertyAccessExpression(entityName: EntityName | PropertyAccessExpression): Symbol | undefined {
             if (isDeclarationName(entityName)) {
                 return getSymbolOfNode(entityName.parent);
             }
 
             if (isInJavaScriptFile(entityName) && entityName.parent.kind === SyntaxKind.PropertyAccessExpression) {
-                const specialPropertyAssignmentKind = getSpecialPropertyAssignmentKind(entityName.parent.parent);
-                switch (specialPropertyAssignmentKind) {
-                    case SpecialPropertyAssignmentKind.ExportsProperty:
-                    case SpecialPropertyAssignmentKind.PrototypeProperty:
-                        return getSymbolOfNode(entityName.parent);
-                    case SpecialPropertyAssignmentKind.ThisProperty:
-                    case SpecialPropertyAssignmentKind.ModuleExports:
-                        return getSymbolOfNode(entityName.parent.parent);
-                    default:
-                        // Fall through if it is not a special property assignment
+                // Check if this is a special property assignment
+                const specialPropertyAssignmentSymbol = getSpecialPropertyAssignmentSymbolFromEntityName(entityName);
+                if (specialPropertyAssignmentSymbol) {
+                    return specialPropertyAssignmentSymbol;
                 }
             }
 

src/compiler/types.ts

@@ -3133,7 +3133,9 @@
         /// className.prototype.name = expr
         PrototypeProperty,
         /// this.name = expr
-        ThisProperty
+        ThisProperty,
+        // F.name = expr
+        Property
     }
 
     export interface FileExtensionInfo {

src/compiler/utilities.ts

@@ -1374,6 +1374,10 @@ namespace ts {
         return false;
     }
 
+    export function isValidSpecialPropertyAssignmentParent(parentSymbol: Symbol) {
+        return parentSymbol && (parentSymbol.flags & SymbolFlags.Function || isDeclarationOfFunctionExpression(parentSymbol));
+    }
+
     /// Given a BinaryExpression, returns SpecialPropertyAssignmentKind for the various kinds of property
     /// assignments we treat as special in the binder
     export function getSpecialPropertyAssignmentKind(expression: Node): SpecialPropertyAssignmentKind {
@@ -1398,6 +1402,10 @@ namespace ts {
                 // module.exports = expr
                 return SpecialPropertyAssignmentKind.ModuleExports;
             }
+            else {
+                // F.x = expr
+                return SpecialPropertyAssignmentKind.Property;
+            }
         }
         else if (lhs.expression.kind === SyntaxKind.ThisKeyword) {
             return SpecialPropertyAssignmentKind.ThisProperty;
@@ -1417,6 +1425,7 @@ namespace ts {
             }
         }
 
+
         return SpecialPropertyAssignmentKind.None;
     }
 

tests/cases/fourslash/renameJsPropertyAssignment.ts

@@ -0,0 +1,11 @@
+/// <reference path='fourslash.ts'/>
+
+// @allowJs: true
+// @Filename: a.js
+////function bar() {
+////}
+////bar.[|foo|] = "foo";
+////console.log(bar./**/[|foo|]);
+
+goTo.marker();
+verify.renameLocations( /*findInStrings*/ false, /*findInComments*/ false);