Do not emit the signature for implementation of overload in the declaration file

Author: sheetalkamat

src/compiler/checker.ts

@@ -5722,6 +5722,14 @@ module ts {
             return false;
         }
 
+        function isImplementationOfOverload(node: FunctionDeclaration) {
+            if (node.body) {
+                var symbol = getSymbolOfNode(node);
+                return getSignaturesOfSymbol(symbol).length > 1;
+            }
+            return false;
+        }
+
         function getNodeCheckFlags(node: Node): NodeCheckFlags {
             return getNodeLinks(node).flags;
         }
@@ -5742,7 +5750,8 @@ module ts {
                 getEnumMemberValue: getEnumMemberValue,
                 isTopLevelValueImportedViaEntityName: isTopLevelValueImportedViaEntityName,
                 shouldEmitDeclarations: shouldEmitDeclarations,
-                isReferencedInExportAssignment: isReferencedInExportAssignment
+                isReferencedInExportAssignment: isReferencedInExportAssignment,
+                isImplementationOfOverload: isImplementationOfOverload
             };
             checkProgram();
             return emitFiles(resolver);

src/compiler/emitter.ts

@@ -2125,9 +2125,9 @@ module ts {
         }
 
         function emitFunctionDeclaration(node: FunctionDeclaration) {
-            // TODO(shkamat): if this is overloaded declaration do not emit if body is present
             // If we are emitting Method/Constructor it isnt moduleElement and doesnt need canEmitModuleElement check
-            if (node.kind !== SyntaxKind.FunctionDeclaration || canEmitModuleElementDeclaration(node)) {
+            if ((node.kind !== SyntaxKind.FunctionDeclaration || canEmitModuleElementDeclaration(node)) &&
+                !resolver.isImplementationOfOverload(node)) {
                 emitDeclarationFlags(node);
                 if (node.kind === SyntaxKind.FunctionDeclaration) {
                     write("function ");

src/compiler/types.ts

@@ -602,6 +602,7 @@ module ts {
         getEnumMemberValue(node: EnumMember): number;
         shouldEmitDeclarations(): boolean;
         isReferencedInExportAssignment(node: Declaration): boolean;
+        isImplementationOfOverload(node: FunctionDeclaration): boolean;
     }
 
     export enum SymbolFlags {

tests/baselines/reference/commentsCommentParsing.js

@@ -242,7 +242,6 @@ declare function sum(a, b);
 declare function multiply(a, b, c?, d?, e?);
 declare function f1(a);
 declare function f1(b);
-declare function f1(aOrb, opt?);
 declare function subtract(a, b, c?, d?, e?, f?);
 declare function square(a);
 declare function divide(a, b);

tests/baselines/reference/commentsOverloads.js

@@ -259,16 +259,12 @@ var c5_i_2 = new c5("hello");
 //// [commentsOverloads.d.ts]
 declare function f1(a);
 declare function f1(b);
-declare function f1(aOrb);
 declare function f2(a);
 declare function f2(b);
-declare function f2(aOrb);
 declare function f3(a);
 declare function f3(b);
-declare function f3(aOrb);
 declare function f4(a);
 declare function f4(b);
-declare function f4(aOrb);
 interface i1 {
     (a);
     (b);
@@ -310,44 +306,34 @@ interface i4 {
 declare class c {
     prop1(a);
     prop1(b);
-    prop1(aorb);
     prop2(a);
     prop2(b);
-    prop2(aorb);
     prop3(a);
     prop3(b);
-    prop3(aorb);
     prop4(a);
     prop4(b);
-    prop4(aorb);
     prop5(a);
     prop5(b);
-    prop5(aorb);
 }
 declare class c1 {
     constructor (a);
     constructor (b);
-    constructor (aorb);
 }
 declare class c2 {
     constructor (a);
     constructor (b);
-    constructor (aorb);
 }
 declare class c3 {
     constructor (a);
     constructor (b);
-    constructor (aorb);
 }
 declare class c4 {
     constructor (a);
     constructor (b);
-    constructor (aorb);
 }
 declare class c5 {
     constructor (a);
     constructor (b);
-    constructor (aorb);
 }
 declare var c_i;
 declare var c1_i_1;

tests/baselines/reference/commentsdoNotEmitComments.js

@@ -142,7 +142,6 @@ declare class c {
     prop1;
     foo1(a);
     foo1(b);
-    foo1(aOrb);
 }
 declare var i;
 interface i1 {

tests/baselines/reference/commentsemitComments.js

@@ -142,7 +142,6 @@ declare class c {
     prop1;
     foo1(a);
     foo1(b);
-    foo1(aOrb);
 }
 declare var i;
 interface i1 {

tests/baselines/reference/declFileConstructors.js

@@ -224,7 +224,6 @@ export declare class ConstructorWithRestParamters {
 export declare class ConstructorWithOverloads {
     constructor (a);
     constructor (a);
-    constructor (a);
 }
 export declare class ConstructorWithPublicParameterProperty {
     x;
@@ -255,7 +254,6 @@ declare class GlobalConstructorWithRestParamters {
 declare class GlobalConstructorWithOverloads {
     constructor (a);
     constructor (a);
-    constructor (a);
 }
 declare class GlobalConstructorWithPublicParameterProperty {
     x;

tests/baselines/reference/declFileForClassWithPrivateOverloadedFunction.js

@@ -20,5 +20,4 @@ var C = (function () {
 declare class C {
     private foo(x);
     private foo(x);
-    private foo(x);
 }

tests/baselines/reference/declFileFunctions.js

@@ -118,11 +118,9 @@ export declare function fooWithParameters(a, b);
 export declare function fooWithRestParameters(a, ...rests);
 export declare function fooWithOverloads(a);
 export declare function fooWithOverloads(a);
-export declare function fooWithOverloads(a);
 //// [declFileFunctions_1.d.ts]
 declare function globalfoo();
 declare function globalfooWithParameters(a, b);
 declare function globalfooWithRestParameters(a, ...rests);
 declare function globalfooWithOverloads(a);
 declare function globalfooWithOverloads(a);
-declare function globalfooWithOverloads(a);

tests/baselines/reference/declFileMethods.js

@@ -332,25 +332,21 @@ export declare class c1 {
     fooWithRestParameters(a, ...rests);
     fooWithOverloads(a);
     fooWithOverloads(a);
-    fooWithOverloads(a);
     private privateFoo();
     private privateFooWithParameters(a, b);
     private privateFooWithRestParameters(a, ...rests);
     private privateFooWithOverloads(a);
     private privateFooWithOverloads(a);
-    private privateFooWithOverloads(a);
     static staticFoo();
     static staticFooWithParameters(a, b);
     static staticFooWithRestParameters(a, ...rests);
     static staticFooWithOverloads(a);
     static staticFooWithOverloads(a);
-    static staticFooWithOverloads(a);
     private static privateStaticFoo();
     private static privateStaticFooWithParameters(a, b);
     private static privateStaticFooWithRestParameters(a, ...rests);
     private static privateStaticFooWithOverloads(a);
     private static privateStaticFooWithOverloads(a);
-    private static privateStaticFooWithOverloads(a);
 }
 export interface I1 {
     foo();
@@ -366,25 +362,21 @@ declare class c2 {
     fooWithRestParameters(a, ...rests);
     fooWithOverloads(a);
     fooWithOverloads(a);
-    fooWithOverloads(a);
     private privateFoo();
     private privateFooWithParameters(a, b);
     private privateFooWithRestParameters(a, ...rests);
     private privateFooWithOverloads(a);
     private privateFooWithOverloads(a);
-    private privateFooWithOverloads(a);
     static staticFoo();
     static staticFooWithParameters(a, b);
     static staticFooWithRestParameters(a, ...rests);
     static staticFooWithOverloads(a);
     static staticFooWithOverloads(a);
-    static staticFooWithOverloads(a);
     private static privateStaticFoo();
     private static privateStaticFooWithParameters(a, b);
     private static privateStaticFooWithRestParameters(a, ...rests);
     private static privateStaticFooWithOverloads(a);
     private static privateStaticFooWithOverloads(a);
-    private static privateStaticFooWithOverloads(a);
 }
 interface I2 {
     foo();

tests/baselines/reference/declFileTypeofFunction.js

@@ -66,10 +66,8 @@ function foo5(x) {
 //// [declFileTypeofFunction.d.ts]
 declare function f(n);
 declare function f(n);
-declare function f();
 declare function g(n);
 declare function g(n);
-declare function g();
 declare var b;
 declare function b1();
 declare function foo();

tests/baselines/reference/funcdecl.js

@@ -153,7 +153,6 @@ declare function withRestParams(a, ...myRestParameter);
 declare var withRestParamsVar;
 declare function overload1(n);
 declare function overload1(s);
-declare function overload1(ns);
 declare var withOverloadSignature;
 declare function f(n);
 declare module m2 {

tests/baselines/reference/methodSignatureDeclarationEmit1.js

@@ -20,5 +20,4 @@ var C = (function () {
 declare class C {
     foo(n);
     foo(s);
-    foo(a);
 }