[Transforms] Fix emit comment in synthesized function expression (#8234)

* Do not emit leading comment of synthesized function expression in object literal property assignment

* Update baselines

src/compiler/printer.ts

@@ -1981,7 +1981,9 @@ const _super = (function (geti, seti) {
                 //          }
                 // "comment1" is not considered to be leading comment for node.initializer
                 // but rather a trailing comment on the previous node.
-                emitLeadingComments(node.initializer, getTrailingComments(collapseRangeToStart(node.initializer)));
+                if (!shouldSkipLeadingCommentsForNode(node.initializer)) {
+                    emitLeadingComments(node.initializer, getTrailingComments(collapseRangeToStart(node.initializer)));
+                }
                 emitExpression(node.initializer);
             }
 

src/compiler/transformers/es6.ts

@@ -1175,13 +1175,25 @@ namespace ts {
             const propertyName = createExpressionForPropertyName(visitNode(firstAccessor.name, visitor, isPropertyName));
             propertyName.end = firstAccessor.name.end;
 
+            let getAccessorExpression: FunctionExpression;
+            if (getAccessor) {
+                getAccessorExpression = transformFunctionLikeToExpression(getAccessor, /*location*/ getAccessor, /*name*/ undefined);
+                setNodeEmitFlags(getAccessorExpression, NodeEmitFlags.NoLeadingComments | getNodeEmitFlags(getAccessorExpression));
+            }
+
+            let setAccessorExpression: FunctionExpression;
+            if (setAccessor) {
+                setAccessorExpression = transformFunctionLikeToExpression(setAccessor, /*location*/ setAccessor, /*name*/ undefined);
+                setNodeEmitFlags(setAccessorExpression, NodeEmitFlags.NoLeadingComments | getNodeEmitFlags(setAccessorExpression));
+            }
+
             return setNodeEmitFlags(
                 createObjectDefineProperty(
                     target,
                     propertyName,
                     /*descriptor*/ {
-                        get: getAccessor && transformFunctionLikeToExpression(getAccessor, /*location*/ getAccessor, /*name*/ undefined),
-                        set: setAccessor && transformFunctionLikeToExpression(setAccessor, /*location*/ setAccessor, /*name*/ undefined),
+                        get: getAccessorExpression,
+                        set: setAccessorExpression,
                         enumerable: true,
                         configurable: true
                     },
@@ -2283,9 +2295,11 @@ namespace ts {
             // Methods on classes are handled in visitClassDeclaration/visitClassExpression.
             // Methods with computed property names are handled in visitObjectLiteralExpression.
             Debug.assert(!isComputedPropertyName(node.name));
+            const functionExpression = transformFunctionLikeToExpression(node, /*location*/ node, /*name*/ undefined);
+            setNodeEmitFlags(functionExpression, NodeEmitFlags.NoLeadingComments | getNodeEmitFlags(functionExpression));
             return createPropertyAssignment(
                 node.name,
-                transformFunctionLikeToExpression(node, /*location*/ node, /*name*/ undefined),
+                functionExpression,
                 /*location*/ node
             );
         }

tests/baselines/reference/callSignaturesWithParameterInitializers2.js

@@ -48,8 +48,7 @@ var b = {
     foo: function (x) {
         if (x === void 0) { x = 1; }
     },
-    foo: // error
-    function (x) {
+    foo: function (x) {
         if (x === void 0) { x = 1; }
     }
 };

tests/baselines/reference/stringIndexerConstrainsPropertyDeclarations.js

@@ -103,8 +103,7 @@ var C = (function () {
     function C() {
     } // ok
     Object.defineProperty(C.prototype, "X", {
-        get: // error
-        function () {
+        get: function () {
             return '';
         },
         set: function (v) { } // ok