Address PR feedback for trailing commas

Author: JsonFreeman

Jakefile

@@ -55,7 +55,7 @@ var servicesSources = [
     "services.ts",
     "shims.ts",
     "signatureHelp.ts",
-	"utilities.ts"
+    "utilities.ts"
 ].map(function (f) {
     return path.join(servicesDirectory, f);
 }));

src/compiler/emitter.ts

@@ -700,23 +700,46 @@ module ts {
                 }
             }
 
-            function emitCommaList(nodes: Node[], count?: number) {
-                if (!(count >= 0)) count = nodes.length;
+            function emitTrailingCommaIfPresent(nodeList: NodeArray<Node>, isMultiline: boolean): void {
+                if (nodeList.hasTrailingComma) {
+                    write(",");
+                    if (isMultiline) {
+                        writeLine();
+                    }
+                }
+            }
+
+            function emitCommaList(nodes: NodeArray<Node>, includeTrailingComma: boolean, count?: number) {
+                if (!(count >= 0)) {
+                    count = nodes.length;
+                }
                 if (nodes) {
                     for (var i = 0; i < count; i++) {
-                        if (i) write(", ");
+                        if (i) {
+                            write(", ");
+                        }
                         emit(nodes[i]);
                     }
+
+                    if (includeTrailingComma) {
+                        emitTrailingCommaIfPresent(nodes, /*isMultiline*/ false);
+                    }
                 }
             }
 
-            function emitMultiLineList(nodes: Node[]) {
+            function emitMultiLineList(nodes: NodeArray<Node>, includeTrailingComma: boolean) {
                 if (nodes) {
                     for (var i = 0; i < nodes.length; i++) {
-                        if (i) write(",");
+                        if (i) {
+                            write(",");
+                        }
                         writeLine();
                         emit(nodes[i]);
                     }
+
+                    if (includeTrailingComma) {
+                        emitTrailingCommaIfPresent(nodes, /*isMultiline*/ true);
+                    }
                 }
             }
 
@@ -824,29 +847,18 @@ module ts {
                 }
             }
 
-            function emitTrailingCommaIfPresent(nodeList: NodeArray<Node>, isMultiline: boolean): void {
-                if (nodeList.hasTrailingComma) {
-                    write(",");
-                    if (isMultiline) {
-                        writeLine();
-                    }
-                }
-            }
-
             function emitArrayLiteral(node: ArrayLiteral) {
                 if (node.flags & NodeFlags.MultiLine) {
                     write("[");
                     increaseIndent();
-                    emitMultiLineList(node.elements);
-                    emitTrailingCommaIfPresent(node.elements, /*isMultiline*/ true);
+                    emitMultiLineList(node.elements, /*includeTrailingComma*/ true);
                     decreaseIndent();
                     writeLine();
                     write("]");
                 }
                 else {
                     write("[");
-                    emitCommaList(node.elements);
-                    emitTrailingCommaIfPresent(node.elements, /*isMultiline*/ false);
+                    emitCommaList(node.elements, /*includeTrailingComma*/ true);
                     write("]");
                 }
             }
@@ -858,24 +870,14 @@ module ts {
                 else if (node.flags & NodeFlags.MultiLine) {
                     write("{");
                     increaseIndent();
-                    emitMultiLineList(node.properties);
-
-                    if (compilerOptions.target === ScriptTarget.ES5) {
-                        emitTrailingCommaIfPresent(node.properties, /*isMultiline*/ true);
-                    }
-
+                    emitMultiLineList(node.properties, /*includeTrailingComma*/ compilerOptions.target >= ScriptTarget.ES5);
                     decreaseIndent();
                     writeLine();
                     write("}");
                 }
                 else {
                     write("{ ");
-                    emitCommaList(node.properties);
-
-                    if (compilerOptions.target === ScriptTarget.ES5) {
-                        emitTrailingCommaIfPresent(node.properties, /*isMultiline*/ false);
-                    }
-
+                    emitCommaList(node.properties, /*includeTrailingComma*/ compilerOptions.target >= ScriptTarget.ES5);
                     write(" }");
                 }
             }
@@ -921,13 +923,13 @@ module ts {
                     emitThis(node.func);
                     if (node.arguments.length) {
                         write(", ");
-                        emitCommaList(node.arguments);
+                        emitCommaList(node.arguments, /*includeTrailingComma*/ false);
                     }
                     write(")");
                 }
                 else {
                     write("(");
-                    emitCommaList(node.arguments);
+                    emitCommaList(node.arguments, /*includeTrailingComma*/ false);
                     write(")");
                 }
             }
@@ -937,7 +939,7 @@ module ts {
                 emit(node.func);
                 if (node.arguments) {
                     write("(");
-                    emitCommaList(node.arguments);
+                    emitCommaList(node.arguments, /*includeTrailingComma*/ false);
                     write(")");
                 }
             }
@@ -1110,7 +1112,7 @@ module ts {
                 if (node.declarations) {
                     emitToken(SyntaxKind.VarKeyword, endPos);
                     write(" ");
-                    emitCommaList(node.declarations);
+                    emitCommaList(node.declarations, /*includeTrailingComma*/ false);
                 }
                 if (node.initializer) {
                     emit(node.initializer);
@@ -1258,7 +1260,7 @@ module ts {
             function emitVariableStatement(node: VariableStatement) {
                 emitLeadingComments(node);
                 if (!(node.flags & NodeFlags.Export)) write("var ");
-                emitCommaList(node.declarations);
+                emitCommaList(node.declarations, /*includeTrailingComma*/ false);
                 write(";");
                 emitTrailingComments(node);
             }
@@ -1367,7 +1369,7 @@ module ts {
                 increaseIndent();
                 write("(");
                 if (node) {
-                    emitCommaList(node.parameters, node.parameters.length - (hasRestParameters(node) ? 1 : 0));
+                    emitCommaList(node.parameters, /*includeTrailingComma*/ false, node.parameters.length - (hasRestParameters(node) ? 1 : 0));
                 }
                 write(")");
                 decreaseIndent();