From 3969b89b234cc642ccbc40f8fbebe3b29c74a80d Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <drosen@microsoft.com>
Date: Mon, 21 Dec 2015 13:40:59 -0800
Subject: [PATCH] Fixups for #6163.

---
 src/compiler/emitter.ts | 34 +++++++++++++++++++---------------
 1 file changed, 19 insertions(+), 15 deletions(-)

diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
index 88d9d20c4c0..996dac118ef 100644
--- a/src/compiler/emitter.ts
+++ b/src/compiler/emitter.ts
@@ -4280,25 +4280,29 @@ var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, Promi
 
                 // TODO (yuisu) : we should not have special cases to condition emitting comments
                 // but have one place to fix check for these conditions.
-                if (node.kind !== SyntaxKind.MethodDeclaration &&
-                    node.kind !== SyntaxKind.MethodSignature &&
-                    node.parent &&
-                    node.parent.kind !== SyntaxKind.PropertyAssignment &&
-                    node.parent.kind !== SyntaxKind.CallExpression &&
-                    node.parent.kind !== SyntaxKind.ArrayLiteralExpression) {
-                    // 1. Methods will emit the comments as part of emitting method declaration
-
+                const { kind, parent } = node;
+                if (kind !== SyntaxKind.MethodDeclaration &&
+                    kind !== SyntaxKind.MethodSignature &&
+                    parent &&
+                    parent.kind !== SyntaxKind.PropertyAssignment &&
+                    parent.kind !== SyntaxKind.CallExpression &&
+                    parent.kind !== SyntaxKind.ArrayLiteralExpression) {
+                    // 1. Methods will emit comments at their assignment declaration sites.
+                    //
                     // 2. If the function is a property of object literal, emitting leading-comments
-                    // is done by emitNodeWithoutSourceMap which then call this function.
-                    // In particular, we would like to avoid emit comments twice in following case:
-                    //      For example:
+                    //    is done by emitNodeWithoutSourceMap which then call this function.
+                    //    In particular, we would like to avoid emit comments twice in following case:
+                    //
                     //          var obj = {
                     //              id:
                     //                  /*comment*/ () => void
                     //          }
-
+                    //
                     // 3. If the function is an argument in call expression, emitting of comments will be
-                    // taken care of in emit list of arguments inside of emitCallexpression
+                    //    taken care of in emit list of arguments inside of 'emitCallExpression'.
+                    //
+                    // 4. If the function is in an array literal, 'emitLinePreservingList' will take care
+                    //    of leading comments.
                     emitLeadingComments(node);
                 }
 
@@ -4325,12 +4329,12 @@ var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, Promi
                 }
 
                 emitSignatureAndBody(node);
-                if (modulekind !== ModuleKind.ES6 && node.kind === SyntaxKind.FunctionDeclaration && node.parent === currentSourceFile && node.name) {
+                if (modulekind !== ModuleKind.ES6 && kind === SyntaxKind.FunctionDeclaration && parent === currentSourceFile && node.name) {
                     emitExportMemberAssignments((<FunctionDeclaration>node).name);
                 }
 
                 emitEnd(node);
-                if (node.kind !== SyntaxKind.MethodDeclaration && node.kind !== SyntaxKind.MethodSignature) {
+                if (kind !== SyntaxKind.MethodDeclaration && kind !== SyntaxKind.MethodSignature) {
                     emitTrailingComments(node);
                 }
             }