diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
index 6626823379b6a..34978ed7fd617 100644
--- a/src/compiler/emitter.ts
+++ b/src/compiler/emitter.ts
@@ -2427,28 +2427,20 @@ module ts {
             }
 
             function emitMethod(node: MethodDeclaration) {
-                if (!isObjectLiteralMethod(node)) {
-                    return;
-                }
-                emitLeadingComments(node);
                 emit(node.name);
                 if (languageVersion < ScriptTarget.ES6) {
                     write(": function ");
                 }
                 emitSignatureAndBody(node);
-                emitTrailingComments(node);
             }
 
             function emitPropertyAssignment(node: PropertyDeclaration) {
-                emitLeadingComments(node);
                 emit(node.name);
                 write(": ");
                 emit(node.initializer);
-                emitTrailingComments(node);
             }
 
             function emitShorthandPropertyAssignment(node: ShorthandPropertyAssignment) {
-                emitLeadingComments(node);
                 emit(node.name);
                 // If short-hand property has a prefix, then regardless of the target version, we will emit it as normal property assignment. For example:
                 //  module m {
@@ -2465,7 +2457,6 @@ module ts {
                     // Short-hand, { x }, is equivalent of normal form { x: x }
                     emitExpressionIdentifier(node.name);
                 }
-                emitTrailingComments(node);
             }
 
             function tryEmitConstantValue(node: PropertyAccessExpression | ElementAccessExpression): boolean {
@@ -2685,14 +2676,11 @@ module ts {
             }
 
             function emitExpressionStatement(node: ExpressionStatement) {
-                emitLeadingComments(node);
                 emitParenthesized(node.expression, /*parenthesized*/ node.expression.kind === SyntaxKind.ArrowFunction);
                 write(";");
-                emitTrailingComments(node);
             }
 
             function emitIfStatement(node: IfStatement) {
-                emitLeadingComments(node);
                 var endPos = emitToken(SyntaxKind.IfKeyword, node.pos);
                 write(" ");
                 endPos = emitToken(SyntaxKind.OpenParenToken, endPos);
@@ -2710,7 +2698,6 @@ module ts {
                         emitEmbeddedStatement(node.elseStatement);
                     }
                 }
-                emitTrailingComments(node);
             }
 
             function emitDoStatement(node: DoStatement) {
@@ -2798,11 +2785,9 @@ module ts {
             }
 
             function emitReturnStatement(node: ReturnStatement) {
-                emitLeadingComments(node);
                 emitToken(SyntaxKind.ReturnKeyword, node.pos);
                 emitOptional(" ", node.expression);
                 write(";");
-                emitTrailingComments(node);
             }
 
             function emitWithStatement(node: WhileStatement) {
@@ -3126,7 +3111,6 @@ module ts {
             }
 
             function emitVariableDeclaration(node: VariableDeclaration) {
-                emitLeadingComments(node);
                 if (isBindingPattern(node.name)) {
                     if (languageVersion < ScriptTarget.ES6) {
                         emitDestructuring(node);
@@ -3140,11 +3124,9 @@ module ts {
                     emitModuleMemberName(node);
                     emitOptional(" = ", node.initializer);
                 }
-                emitTrailingComments(node);
             }
 
             function emitVariableStatement(node: VariableStatement) {
-                emitLeadingComments(node);
                 if (!(node.flags & NodeFlags.Export)) {
                     if (isLet(node.declarationList)) {
                         write("let ");
@@ -3158,11 +3140,9 @@ module ts {
                 }
                 emitCommaList(node.declarationList.declarations);
                 write(";");
-                emitTrailingComments(node);
             }
 
             function emitParameter(node: ParameterDeclaration) {
-                emitLeadingComments(node);
                 if (languageVersion < ScriptTarget.ES6) {
                     if (isBindingPattern(node.name)) {
                         var name = createTempVariable(node);
@@ -3183,7 +3163,6 @@ module ts {
                     emit(node.name);
                     emitOptional(" = ", node.initializer);
                 }
-                emitTrailingComments(node);
             }
 
             function emitDefaultValueAssignments(node: FunctionLikeDeclaration) {
@@ -3256,11 +3235,9 @@ module ts {
             }
 
             function emitAccessor(node: AccessorDeclaration) {
-                emitLeadingComments(node);
                 write(node.kind === SyntaxKind.GetAccessor ? "get " : "set ");
                 emit(node.name);
                 emitSignatureAndBody(node);
-                emitTrailingComments(node);
             }
 
             function emitFunctionDeclaration(node: FunctionLikeDeclaration) {
@@ -3330,7 +3307,10 @@ module ts {
                     write(" ");
                     emitStart(node.body);
                     write("return ");
-                    emitNode(node.body);
+
+                    // Don't emit comments on this body.  We'll have already taken care of it above 
+                    // when we called emitDetachedComments.
+                    emitNode(node.body, /*disableComments:*/ true);
                     emitEnd(node.body);
                     write(";");
                     emitTempDeclarations(/*newLine*/ false);
@@ -3347,7 +3327,7 @@ module ts {
                         writeLine();
                         emitLeadingComments(node.body);
                         write("return ");
-                        emit(node.body);
+                        emit(node.body, /*disableComments:*/ true);
                         write(";");
                         emitTrailingComments(node.body);
                     }
@@ -3528,7 +3508,6 @@ module ts {
             }
 
             function emitClassDeclaration(node: ClassDeclaration) {
-                emitLeadingComments(node);
                 write("var ");
                 emit(node.name);
                 write(" = (function (");
@@ -3578,7 +3557,6 @@ module ts {
                     emitEnd(node);
                     write(";");
                 }
-                emitTrailingComments(node);
 
                 function emitConstructorOfClass() {
                     var saveTempCount = tempCount;
@@ -3657,13 +3635,17 @@ module ts {
                 emitPinnedOrTripleSlashComments(node);
             }
 
+            function shouldEmitEnumDeclaration(node: EnumDeclaration) {
+                var isConstEnum = isConst(node);
+                return !isConstEnum || compilerOptions.preserveConstEnums;
+            }
+
             function emitEnumDeclaration(node: EnumDeclaration) {
                 // const enums are completely erased during compilation.
-                var isConstEnum = isConst(node);
-                if (isConstEnum && !compilerOptions.preserveConstEnums) {
+                if (!shouldEmitEnumDeclaration(node)) {
                     return;
                 }
-                emitLeadingComments(node);
+
                 if (!(node.flags & NodeFlags.Export)) {
                     emitStart(node);
                     write("var ");
@@ -3680,7 +3662,7 @@ module ts {
                 write(") {");
                 increaseIndent();
                 scopeEmitStart(node);
-                emitEnumMemberDeclarations(isConstEnum);
+                emitLines(node.members);
                 decreaseIndent();
                 writeLine();
                 emitToken(SyntaxKind.CloseBraceToken, node.members.end);
@@ -3701,32 +3683,27 @@ module ts {
                     emitEnd(node);
                     write(";");
                 }
-                emitTrailingComments(node);
+            }
 
-                function emitEnumMemberDeclarations(isConstEnum: boolean) {
-                    forEach(node.members, member => {
-                        writeLine();
-                        emitLeadingComments(member);
-                        emitStart(member);
-                        write(resolver.getLocalNameOfContainer(node));
-                        write("[");
-                        write(resolver.getLocalNameOfContainer(node));
-                        write("[");
-                        emitExpressionForPropertyName(member.name);
-                        write("] = ");
-                        if (member.initializer && !isConstEnum) {
-                            emit(member.initializer);
-                        }
-                        else {
-                            write(resolver.getEnumMemberValue(member).toString());
-                        }
-                        write("] = ");
-                        emitExpressionForPropertyName(member.name);
-                        emitEnd(member);
-                        write(";");
-                        emitTrailingComments(member);
-                    });
+            function emitEnumMember(node: EnumMember) {
+                var enumParent = <EnumDeclaration>node.parent;
+                emitStart(node);
+                write(resolver.getLocalNameOfContainer(enumParent));
+                write("[");
+                write(resolver.getLocalNameOfContainer(enumParent));
+                write("[");
+                emitExpressionForPropertyName(node.name);
+                write("] = ");
+                if (node.initializer && !isConst(enumParent)) {
+                    emit(node.initializer);
+                }
+                else {
+                    write(resolver.getEnumMemberValue(node).toString());
                 }
+                write("] = ");
+                emitExpressionForPropertyName(node.name);
+                emitEnd(node);
+                write(";");
             }
 
             function getInnerMostModuleDeclarationFromDottedModule(moduleDeclaration: ModuleDeclaration): ModuleDeclaration {
@@ -3736,14 +3713,18 @@ module ts {
                 }
             }
 
+            function shouldEmitModuleDeclaration(node: ModuleDeclaration) {
+                return isInstantiatedModule(node, compilerOptions.preserveConstEnums);
+            }
+
             function emitModuleDeclaration(node: ModuleDeclaration) {
                 // Emit only if this module is non-ambient.
-                var shouldEmit = isInstantiatedModule(node, compilerOptions.preserveConstEnums);
+                var shouldEmit = shouldEmitModuleDeclaration(node);
 
                 if (!shouldEmit) {
                     return emitPinnedOrTripleSlashComments(node);
                 }
-                emitLeadingComments(node);
+
                 emitStart(node);
                 write("var ");
                 emit(node.name);
@@ -3788,7 +3769,6 @@ module ts {
                 emitModuleMemberName(node);
                 write(" = {}));");
                 emitEnd(node);
-                emitTrailingComments(node);
             }
 
             function emitImportDeclaration(node: ImportDeclaration) {
@@ -3978,7 +3958,7 @@ module ts {
                 emitLeadingComments(node.endOfFileToken);
             }
 
-            function emitNode(node: Node): void {
+            function emitNode(node: Node, disableComments?:boolean): void {
                 if (!node) {
                     return;
                 }
@@ -3986,6 +3966,46 @@ module ts {
                 if (node.flags & NodeFlags.Ambient) {
                     return emitPinnedOrTripleSlashComments(node);
                 }
+
+                var emitComments = !disableComments && shouldEmitLeadingAndTrailingComments(node);
+                if (emitComments) {
+                    emitLeadingComments(node);
+                }
+
+                emitJavaScriptWorker(node);
+
+                if (emitComments) {
+                    emitTrailingComments(node);
+                }
+            }
+
+            function shouldEmitLeadingAndTrailingComments(node: Node) {
+                switch (node.kind) {
+                    // All of these entities are emitted in a specialized fashion.  As such, we allow
+                    // the specilized methods for each to handle the comments on the nodes.
+                    case SyntaxKind.InterfaceDeclaration:
+                    case SyntaxKind.FunctionDeclaration:
+                    case SyntaxKind.ImportDeclaration:
+                    case SyntaxKind.TypeAliasDeclaration:
+                    case SyntaxKind.ExportAssignment:
+                        return false;
+
+                    case SyntaxKind.ModuleDeclaration:
+                        // Only emit the leading/trailing comments for a module if we're actually 
+                        // emitting the module as well.
+                        return shouldEmitModuleDeclaration(<ModuleDeclaration>node);
+
+                    case SyntaxKind.EnumDeclaration:
+                        // Only emit the leading/trailing comments for an enum if we're actually 
+                        // emitting the module as well.
+                        return shouldEmitEnumDeclaration(<EnumDeclaration>node);
+                }
+
+                // Emit comments for everything else.
+                return true;
+            }
+
+            function emitJavaScriptWorker(node: Node) {
                 // Check if the node can be emitted regardless of the ScriptTarget
                 switch (node.kind) {
                     case SyntaxKind.Identifier:
@@ -4123,6 +4143,8 @@ module ts {
                         return emitInterfaceDeclaration(<InterfaceDeclaration>node);
                     case SyntaxKind.EnumDeclaration:
                         return emitEnumDeclaration(<EnumDeclaration>node);
+                    case SyntaxKind.EnumMember:
+                        return emitEnumMember(<EnumMember>node);
                     case SyntaxKind.ModuleDeclaration:
                         return emitModuleDeclaration(<ModuleDeclaration>node);
                     case SyntaxKind.ImportDeclaration:
@@ -4152,17 +4174,19 @@ module ts {
 
             function getLeadingCommentsToEmit(node: Node) {
                 // Emit the leading comments only if the parent's pos doesn't match because parent should take care of emitting these comments
-                if (node.parent.kind === SyntaxKind.SourceFile || node.pos !== node.parent.pos) {
-                    var leadingComments: CommentRange[];
-                    if (hasDetachedComments(node.pos)) {
-                        // get comments without detached comments
-                        leadingComments = getLeadingCommentsWithoutDetachedComments();
-                    }
-                    else {
-                        // get the leading comments from the node
-                        leadingComments = getLeadingCommentRangesOfNode(node, currentSourceFile);
+                if (node.parent) {
+                    if (node.parent.kind === SyntaxKind.SourceFile || node.pos !== node.parent.pos) {
+                        var leadingComments: CommentRange[];
+                        if (hasDetachedComments(node.pos)) {
+                            // get comments without detached comments
+                            leadingComments = getLeadingCommentsWithoutDetachedComments();
+                        }
+                        else {
+                            // get the leading comments from the node
+                            leadingComments = getLeadingCommentRangesOfNode(node, currentSourceFile);
+                        }
+                        return leadingComments;
                     }
-                    return leadingComments;
                 }
             }
 
@@ -4175,10 +4199,12 @@ module ts {
 
             function emitTrailingDeclarationComments(node: Node) {
                 // Emit the trailing comments only if the parent's end doesn't match
-                if (node.parent.kind === SyntaxKind.SourceFile || node.end !== node.parent.end) {
-                    var trailingComments = getTrailingCommentRanges(currentSourceFile.text, node.end);
-                    // trailing comments are emitted at space/*trailing comment1 */space/*trailing comment*/
-                    emitComments(currentSourceFile, writer, trailingComments, /*trailingSeparator*/ false, newLine, writeComment);                    
+                if (node.parent) {
+                    if (node.parent.kind === SyntaxKind.SourceFile || node.end !== node.parent.end) {
+                        var trailingComments = getTrailingCommentRanges(currentSourceFile.text, node.end);
+                        // trailing comments are emitted at space/*trailing comment1 */space/*trailing comment*/
+                        emitComments(currentSourceFile, writer, trailingComments, /*trailingSeparator*/ false, newLine, writeComment);
+                    }
                 }
             }
 
diff --git a/tests/baselines/reference/arrowFunctionContexts.js b/tests/baselines/reference/arrowFunctionContexts.js
index abb8fd0ab7acb..cdf902a6c379e 100644
--- a/tests/baselines/reference/arrowFunctionContexts.js
+++ b/tests/baselines/reference/arrowFunctionContexts.js
@@ -103,6 +103,7 @@ var __extends = this.__extends || function (d, b) {
     __.prototype = b.prototype;
     d.prototype = new __();
 };
+// Arrow function used in with statement
 with (window) {
     var p = function () { return this; };
 }
@@ -142,6 +143,7 @@ var M;
 // Repeat above for module members that are functions? (necessary to redo all of them?)
 var M2;
 (function (M2) {
+    // Arrow function used in with statement
     with (window) {
         var p = function () { return this; };
     }
diff --git a/tests/baselines/reference/augmentedTypesEnum2.js b/tests/baselines/reference/augmentedTypesEnum2.js
index 434e508f14c04..f0c86e5640b8a 100644
--- a/tests/baselines/reference/augmentedTypesEnum2.js
+++ b/tests/baselines/reference/augmentedTypesEnum2.js
@@ -31,7 +31,7 @@ var e2;
 (function (e2) {
     e2[e2["One"] = 0] = "One";
 })(e2 || (e2 = {}));
-;
+; // error
 var e2 = (function () {
     function e2() {
     }
diff --git a/tests/baselines/reference/augmentedTypesInterface.js b/tests/baselines/reference/augmentedTypesInterface.js
index a5039f8b1d011..e28864fd547c7 100644
--- a/tests/baselines/reference/augmentedTypesInterface.js
+++ b/tests/baselines/reference/augmentedTypesInterface.js
@@ -47,5 +47,5 @@ var i3;
 (function (i3) {
     i3[i3["One"] = 0] = "One";
 })(i3 || (i3 = {}));
-;
+; // error
 //import i4 = require('');  // error 
diff --git a/tests/baselines/reference/augmentedTypesModules.js b/tests/baselines/reference/augmentedTypesModules.js
index a9bff3fa74b82..3b7544996a18f 100644
--- a/tests/baselines/reference/augmentedTypesModules.js
+++ b/tests/baselines/reference/augmentedTypesModules.js
@@ -124,21 +124,21 @@ var m1d;
 var m1d = 1; // error
 function m2() {
 }
-;
+; // ok since the module is not instantiated
 var m2a;
 (function (m2a) {
     var y = 2;
 })(m2a || (m2a = {}));
 function m2a() {
 }
-;
+; // error since the module is instantiated
 var m2b;
 (function (m2b) {
     m2b.y = 2;
 })(m2b || (m2b = {}));
 function m2b() {
 }
-;
+; // error since the module is instantiated
 // should be errors to have function first
 function m2c() {
 }
diff --git a/tests/baselines/reference/augmentedTypesModules2.js b/tests/baselines/reference/augmentedTypesModules2.js
index d1551b6244e9c..70fd31f03e076 100644
--- a/tests/baselines/reference/augmentedTypesModules2.js
+++ b/tests/baselines/reference/augmentedTypesModules2.js
@@ -31,21 +31,21 @@ module m2g { export class C { foo() { } } }
 //// [augmentedTypesModules2.js]
 function m2() {
 }
-;
+; // ok since the module is not instantiated
 var m2a;
 (function (m2a) {
     var y = 2;
 })(m2a || (m2a = {}));
 function m2a() {
 }
-;
+; // error since the module is instantiated
 var m2b;
 (function (m2b) {
     m2b.y = 2;
 })(m2b || (m2b = {}));
 function m2b() {
 }
-;
+; // error since the module is instantiated
 function m2c() {
 }
 ;
@@ -59,7 +59,7 @@ var m2cc;
 })(m2cc || (m2cc = {}));
 function m2cc() {
 }
-;
+; // error to have module first
 function m2f() {
 }
 ;
diff --git a/tests/baselines/reference/commaOperatorOtherValidOperation.js b/tests/baselines/reference/commaOperatorOtherValidOperation.js
index 4d556472adc60..383b7c5058e33 100644
--- a/tests/baselines/reference/commaOperatorOtherValidOperation.js
+++ b/tests/baselines/reference/commaOperatorOtherValidOperation.js
@@ -22,6 +22,7 @@ function foo1<T1, T2>()
 
 
 //// [commaOperatorOtherValidOperation.js]
+//Comma operator in for loop
 for (var i = 0, j = 10; i < j; i++, j--) {
 }
 //Comma operator in fuction arguments and return
diff --git a/tests/baselines/reference/commentsOnObjectLiteral1.js b/tests/baselines/reference/commentsOnObjectLiteral1.js
index 1c47ed68d8d4c..feb6a521b8db4 100644
--- a/tests/baselines/reference/commentsOnObjectLiteral1.js
+++ b/tests/baselines/reference/commentsOnObjectLiteral1.js
@@ -8,4 +8,8 @@ var Person = makeClass(
 );
 
 //// [commentsOnObjectLiteral1.js]
-var Person = makeClass({});
+var Person = makeClass(
+/**
+  @scope Person
+*/
+{});
diff --git a/tests/baselines/reference/commentsVarDecl.js b/tests/baselines/reference/commentsVarDecl.js
index 5105e03879da5..5ff2a3c1c6a85 100644
--- a/tests/baselines/reference/commentsVarDecl.js
+++ b/tests/baselines/reference/commentsVarDecl.js
@@ -66,7 +66,9 @@ var n = 30;
 /** var deckaration with comment on type as well*/
 var y = 20;
 /// var deckaration with comment on type as well
-var yy = 20;
+var yy = 
+/// value comment
+20;
 /** comment2 */
 var z = function (x, y) { return x + y; };
 var z2;
diff --git a/tests/baselines/reference/constDeclarations-scopes.js b/tests/baselines/reference/constDeclarations-scopes.js
index aa1d59aee811e..b1be921849c4c 100644
--- a/tests/baselines/reference/constDeclarations-scopes.js
+++ b/tests/baselines/reference/constDeclarations-scopes.js
@@ -189,6 +189,7 @@ while (false) {
     label2: label3: label4: const c = 0;
     n = c;
 }
+// Try/catch/finally
 try {
     const c = 0;
     n = c;
@@ -201,12 +202,14 @@ finally {
     const c = 0;
     n = c;
 }
+// Switch
 switch (0) {
     case 0:
         const c = 0;
         n = c;
         break;
 }
+// blocks
 {
     const c = 0;
     n = c;
diff --git a/tests/baselines/reference/constDeclarations-scopes2.js b/tests/baselines/reference/constDeclarations-scopes2.js
index 1d0f252ab4f2d..d407cf56801bd 100644
--- a/tests/baselines/reference/constDeclarations-scopes2.js
+++ b/tests/baselines/reference/constDeclarations-scopes2.js
@@ -20,6 +20,7 @@ for (const c = 0; c < 10; n = c ) {
 const c = "string";
 var n;
 var b;
+// for scope
 for (const c = 0; c < 10; n = c) {
     // for block
     const c = false;
diff --git a/tests/baselines/reference/constDeclarations-validContexts.js b/tests/baselines/reference/constDeclarations-validContexts.js
index 8be43633d7071..8238f69ca15b7 100644
--- a/tests/baselines/reference/constDeclarations-validContexts.js
+++ b/tests/baselines/reference/constDeclarations-validContexts.js
@@ -153,6 +153,7 @@ if (true) {
 while (false) {
     label2: label3: label4: const c9 = 0;
 }
+// Try/catch/finally
 try {
     const c10 = 0;
 }
@@ -162,6 +163,7 @@ catch (e) {
 finally {
     const c12 = 0;
 }
+// Switch
 switch (0) {
     case 0:
         const c13 = 0;
@@ -170,6 +172,7 @@ switch (0) {
         const c14 = 0;
         break;
 }
+// blocks
 {
     const c15 = 0;
     {
diff --git a/tests/baselines/reference/escapedIdentifiers.js b/tests/baselines/reference/escapedIdentifiers.js
index cabeb7f1d5d2d..5de505e4cb7fc 100644
--- a/tests/baselines/reference/escapedIdentifiers.js
+++ b/tests/baselines/reference/escapedIdentifiers.js
@@ -204,19 +204,20 @@ constructorTestObject.arg\u0031 = 1;
 constructorTestObject.arg2 = 'string';
 constructorTestObject.arg\u0033 = true;
 constructorTestObject.arg4 = 2;
+// Lables
 l\u0061bel1: while (false) {
     while (false)
-        continue label1;
+        continue label1; // it will go to next iteration of outer loop 
 }
 label2: while (false) {
     while (false)
-        continue l\u0061bel2;
+        continue l\u0061bel2; // it will go to next iteration of outer loop 
 }
 label3: while (false) {
     while (false)
-        continue label3;
+        continue label3; // it will go to next iteration of outer loop 
 }
 l\u0061bel4: while (false) {
     while (false)
-        continue l\u0061bel4;
+        continue l\u0061bel4; // it will go to next iteration of outer loop 
 }
diff --git a/tests/baselines/reference/forStatementsMultipleInvalidDecl.js b/tests/baselines/reference/forStatementsMultipleInvalidDecl.js
index 73db1ff3c7d26..4dbfe7e62bc76 100644
--- a/tests/baselines/reference/forStatementsMultipleInvalidDecl.js
+++ b/tests/baselines/reference/forStatementsMultipleInvalidDecl.js
@@ -93,6 +93,7 @@ var M;
     }
     M.F2 = F2;
 })(M || (M = {}));
+// all of these are errors
 for (var a;;) {
 }
 for (var a = 1;;) {
diff --git a/tests/baselines/reference/genericChainedCalls.js b/tests/baselines/reference/genericChainedCalls.js
index 618d34cbc5a63..71d83a906bf33 100644
--- a/tests/baselines/reference/genericChainedCalls.js
+++ b/tests/baselines/reference/genericChainedCalls.js
@@ -15,7 +15,8 @@ var s3 = s2.func(num => num.toString())
 
 
 //// [genericChainedCalls.js]
-var r1 = v1.func(function (num) { return num.toString(); }).func(function (str) { return str.length; }).func(function (num) { return num.toString(); });
+var r1 = v1.func(function (num) { return num.toString(); }).func(function (str) { return str.length; }) // error, number doesn't have a length
+.func(function (num) { return num.toString(); });
 var s1 = v1.func(function (num) { return num.toString(); });
 var s2 = s1.func(function (str) { return str.length; }); // should also error
 var s3 = s2.func(function (num) { return num.toString(); });
diff --git a/tests/baselines/reference/implicitAnyDeclareFunctionWithoutFormalType.js b/tests/baselines/reference/implicitAnyDeclareFunctionWithoutFormalType.js
index 72d68da22872b..6332f4444871e 100644
--- a/tests/baselines/reference/implicitAnyDeclareFunctionWithoutFormalType.js
+++ b/tests/baselines/reference/implicitAnyDeclareFunctionWithoutFormalType.js
@@ -18,22 +18,22 @@ function foo(x) {
 ;
 function bar(x, y) {
 }
-;
+; // error at "y"; no error at "x"
 function func2(a, b, c) {
 }
-;
+; // error at "a,b,c"
 function func3() {
     var args = [];
     for (var _i = 0; _i < arguments.length; _i++) {
         args[_i - 0] = arguments[_i];
     }
 }
-;
+; // error at "args" 
 function func4(z, w) {
     if (z === void 0) { z = null; }
     if (w === void 0) { w = undefined; }
 }
-;
+; // error at "z,w"
 // these shouldn't be errors
 function noError1(x, y) {
     if (x === void 0) { x = 3; }
diff --git a/tests/baselines/reference/implicitAnyDeclareVariablesWithoutTypeAndInit.js b/tests/baselines/reference/implicitAnyDeclareVariablesWithoutTypeAndInit.js
index 95b617d79ee9c..ae09bf2e40e6d 100644
--- a/tests/baselines/reference/implicitAnyDeclareVariablesWithoutTypeAndInit.js
+++ b/tests/baselines/reference/implicitAnyDeclareVariablesWithoutTypeAndInit.js
@@ -16,7 +16,7 @@ var x1: any; var y1 = new x1;
 var x; // error at "x"
 function func(k) {
 }
-;
+; //error at "k"
 func(x);
 // this shouldn't be an error
 var bar = 3;
diff --git a/tests/baselines/reference/implicitAnyInCatch.js b/tests/baselines/reference/implicitAnyInCatch.js
index 9952c7ca327a3..29a2e03a130b9 100644
--- a/tests/baselines/reference/implicitAnyInCatch.js
+++ b/tests/baselines/reference/implicitAnyInCatch.js
@@ -15,6 +15,7 @@ class C {
 
 
 //// [implicitAnyInCatch.js]
+// this should not be an error
 try {
 }
 catch (error) {
diff --git a/tests/baselines/reference/letDeclarations-scopes.js b/tests/baselines/reference/letDeclarations-scopes.js
index d0f70693d7c07..dbe18311eff7f 100644
--- a/tests/baselines/reference/letDeclarations-scopes.js
+++ b/tests/baselines/reference/letDeclarations-scopes.js
@@ -205,6 +205,7 @@ for (let l = 0; n = l; l++) {
 }
 for (let l in {}) {
 }
+// Try/catch/finally
 try {
     let l = 0;
     n = l;
@@ -217,12 +218,14 @@ finally {
     let l = 0;
     n = l;
 }
+// Switch
 switch (0) {
     case 0:
         let l = 0;
         n = l;
         break;
 }
+// blocks
 {
     let l = 0;
     n = l;
diff --git a/tests/baselines/reference/letDeclarations-validContexts.js b/tests/baselines/reference/letDeclarations-validContexts.js
index fe9ed903bf5a1..ee821794b12d1 100644
--- a/tests/baselines/reference/letDeclarations-validContexts.js
+++ b/tests/baselines/reference/letDeclarations-validContexts.js
@@ -173,6 +173,7 @@ if (true) {
 while (false) {
     label2: label3: label4: let l9 = 0;
 }
+// Try/catch/finally
 try {
     let l10 = 0;
 }
@@ -182,6 +183,7 @@ catch (e) {
 finally {
     let l12 = 0;
 }
+// Switch
 switch (0) {
     case 0:
         let l13 = 0;
@@ -190,6 +192,7 @@ switch (0) {
         let l14 = 0;
         break;
 }
+// blocks
 {
     let l15 = 0;
     {
@@ -247,6 +250,7 @@ var o = {
         let l29 = 0;
     }
 };
+// labels
 label: let l30 = 0;
 {
     label2: let l31 = 0;
diff --git a/tests/baselines/reference/overEagerReturnTypeSpecialization.js b/tests/baselines/reference/overEagerReturnTypeSpecialization.js
index 18c61a2aa78de..67d2005eca99c 100644
--- a/tests/baselines/reference/overEagerReturnTypeSpecialization.js
+++ b/tests/baselines/reference/overEagerReturnTypeSpecialization.js
@@ -16,5 +16,7 @@ var r2: I1<number> = v1.func(num => num.toString()) // Correctly returns an I1<s
 
 //// [overEagerReturnTypeSpecialization.js]
 //Note: Below simpler repro
-var r1 = v1.func(function (num) { return num.toString(); }).func(function (str) { return str.length; }); // should error
-var r2 = v1.func(function (num) { return num.toString(); }).func(function (str) { return str.length; }); // should be ok 
+var r1 = v1.func(function (num) { return num.toString(); }) // Correctly returns an I1<string>
+.func(function (str) { return str.length; }); // should error
+var r2 = v1.func(function (num) { return num.toString(); }) // Correctly returns an I1<string>
+.func(function (str) { return str.length; }); // should be ok 
diff --git a/tests/baselines/reference/parserSbp_7.9_A9_T3.js b/tests/baselines/reference/parserSbp_7.9_A9_T3.js
index 60c8c4ad6eba6..192ca6172117a 100644
--- a/tests/baselines/reference/parserSbp_7.9_A9_T3.js
+++ b/tests/baselines/reference/parserSbp_7.9_A9_T3.js
@@ -19,6 +19,13 @@ do {
 //// [parserSbp_7.9_A9_T3.js]
 // Copyright 2009 the Sputnik authors.  All rights reserved.
 // This code is governed by the BSD license found in the LICENSE file.
+/**
+ * Check Do-While Statement for automatic semicolon insertion
+ *
+ * @path bestPractice/Sbp_7.9_A9_T3.js
+ * @description Execute do { \n ; \n }while(false) true
+ */
+//CHECK#1
 do {
     ;
 } while (false);
diff --git a/tests/baselines/reference/promiseChaining.js b/tests/baselines/reference/promiseChaining.js
index 20961542b2277..ce15e2d44c161 100644
--- a/tests/baselines/reference/promiseChaining.js
+++ b/tests/baselines/reference/promiseChaining.js
@@ -19,7 +19,7 @@ var Chain = (function () {
     Chain.prototype.then = function (cb) {
         var result = cb(this.value);
         // should get a fresh type parameter which each then call
-        var z = this.then(function (x) { return result; }).then(function (x) { return "abc"; }).then(function (x) { return x.length; }); // No error
+        var z = this.then(function (x) { return result; }) /*S*/.then(function (x) { return "abc"; }) /*string*/.then(function (x) { return x.length; }); // No error
         return new Chain(result);
     };
     return Chain;
diff --git a/tests/baselines/reference/promiseChaining1.js b/tests/baselines/reference/promiseChaining1.js
index ee79d3268ba98..001f1ffc1a676 100644
--- a/tests/baselines/reference/promiseChaining1.js
+++ b/tests/baselines/reference/promiseChaining1.js
@@ -19,7 +19,7 @@ var Chain2 = (function () {
     Chain2.prototype.then = function (cb) {
         var result = cb(this.value);
         // should get a fresh type parameter which each then call
-        var z = this.then(function (x) { return result; }).then(function (x) { return "abc"; }).then(function (x) { return x.length; }); // Should error on "abc" because it is not a Function
+        var z = this.then(function (x) { return result; }) /*S*/.then(function (x) { return "abc"; }) /*Function*/.then(function (x) { return x.length; }); // Should error on "abc" because it is not a Function
         return new Chain2(result);
     };
     return Chain2;
diff --git a/tests/baselines/reference/recursiveInitializer.js b/tests/baselines/reference/recursiveInitializer.js
index c7a723c35d770..82abf2b50af9d 100644
--- a/tests/baselines/reference/recursiveInitializer.js
+++ b/tests/baselines/reference/recursiveInitializer.js
@@ -23,10 +23,10 @@ var f = (x: string) => f(x);
 // number unless otherwise specified
 var n1 = n1++;
 var n2 = n2 + n2;
-var n3 = n3 + n3;
+var n3 /* any */ = n3 + n3;
 // string unless otherwise specified
 var s1 = s1 + '';
-var s2 = s2 + s2;
+var s2 /* any */ = s2 + s2;
 var s3 = s3 + s3;
 var s4 = '' + s4;
 // boolean unless otherwise specified
diff --git a/tests/baselines/reference/scopingInCatchBlocks.js b/tests/baselines/reference/scopingInCatchBlocks.js
index 8590173147c86..2d3ca7098b59f 100644
--- a/tests/baselines/reference/scopingInCatchBlocks.js
+++ b/tests/baselines/reference/scopingInCatchBlocks.js
@@ -19,9 +19,9 @@ catch (ex1) {
 try {
 }
 catch (ex1) {
-}
+} // should not error
 try {
 }
 catch (ex1) {
-}
+} // should not error
 var x = ex1; // should error
diff --git a/tests/baselines/reference/sourceMapValidationClasses.js b/tests/baselines/reference/sourceMapValidationClasses.js
index 96724f7c3c770..e3b705bc4b025 100644
--- a/tests/baselines/reference/sourceMapValidationClasses.js
+++ b/tests/baselines/reference/sourceMapValidationClasses.js
@@ -57,9 +57,9 @@ var Foo;
         var greeter = new Greeter("Hello, world!");
         var str = greeter.greet();
         function foo2(greeting) {
-            var restGreetings = [];
+            var restGreetings /* more greeting */ = [];
             for (var _i = 1; _i < arguments.length; _i++) {
-                restGreetings[_i - 1] = arguments[_i];
+                restGreetings /* more greeting */[_i - 1] = arguments[_i];
             }
             var greeters = []; /* inline block comment */
             greeters[0] = new Greeter(greeting);
@@ -69,6 +69,7 @@ var Foo;
             return greeters;
         }
         var b = foo2("Hello", "World", "!");
+        // This is simple signle line comment
         for (var j = 0; j < b.length; j++) {
             b[j].greet();
         }
diff --git a/tests/baselines/reference/sourceMapValidationClasses.js.map b/tests/baselines/reference/sourceMapValidationClasses.js.map
index 2a1b381e11639..68ded9631e2e9 100644
--- a/tests/baselines/reference/sourceMapValidationClasses.js.map
+++ b/tests/baselines/reference/sourceMapValidationClasses.js.map
@@ -1,2 +1,2 @@
 //// [sourceMapValidationClasses.js.map]
-{"version":3,"file":"sourceMapValidationClasses.js","sourceRoot":"","sources":["sourceMapValidationClasses.ts"],"names":["Foo","Foo.Bar","Foo.Bar.Greeter","Foo.Bar.Greeter.constructor","Foo.Bar.Greeter.greet","Foo.Bar.foo","Foo.Bar.foo2"],"mappings":"AAAA,IAAO,GAAG,CAmCT;AAnCD,WAAO,GAAG;IAACA,IAAAA,GAAGA,CAmCbA;IAnCUA,WAAAA,GAAGA,EAACA,CAACA;QACZC,YAAYA,CAACA;QAEbA,IAAMA,OAAOA;YACTC,SADEA,OAAOA,CACUA,QAAgBA;gBAAhBC,aAAQA,GAARA,QAAQA,CAAQA;YACnCA,CAACA;YAEDD,uBAAKA,GAALA;gBACIE,MAAMA,CAACA,MAAMA,GAAGA,IAAIA,CAACA,QAAQA,GAAGA,OAAOA,CAACA;YAC5CA,CAACA;YACLF,cAACA;QAADA,CAACA,AAPDD,IAOCA;QAGDA,SAASA,GAAGA,CAACA,QAAgBA;YACzBI,MAAMA,CAACA,IAAIA,OAAOA,CAACA,QAAQA,CAACA,CAACA;QACjCA,CAACA;QAEDJ,IAAIA,OAAOA,GAAGA,IAAIA,OAAOA,CAACA,eAAeA,CAACA,CAACA;QAC3CA,IAAIA,GAAGA,GAAGA,OAAOA,CAACA,KAAKA,EAAEA,CAACA;QAE1BA,SAASA,IAAIA,CAACA,QAAgBA;YAAEK,uBAA8CA;iBAA9CA,WAA8CA,CAA9CA,sBAA8CA,CAA9CA,IAA8CA;gBAA9CA,sCAA8CA;;YAC1EA,IAAIA,QAAQA,GAAcA,EAAEA,EAAEA,0BAA0BA,AAA3BA;YAC7BA,QAAQA,CAACA,CAACA,CAACA,GAAGA,IAAIA,OAAOA,CAACA,QAAQA,CAACA,CAACA;YACpCA,GAAGA,CAACA,CAACA,GAAGA,CAACA,CAACA,GAAGA,CAACA,EAAEA,CAACA,GAAGA,aAAaA,CAACA,MAAMA,EAAEA,CAACA,EAAEA,EAAEA,CAACA;gBAC5CA,QAAQA,CAACA,IAAIA,CAACA,IAAIA,OAAOA,CAACA,aAAaA,CAACA,CAACA,CAACA,CAACA,CAACA,CAACA;YACjDA,CAACA;YAEDA,MAAMA,CAACA,QAAQA,CAACA;QACpBA,CAACA;QAEDL,IAAIA,CAACA,GAAGA,IAAIA,CAACA,OAAOA,EAAEA,OAAOA,EAAEA,GAAGA,CAACA,CAACA;QAEpCA,GAAGA,CAACA,CAACA,GAAGA,CAACA,CAACA,GAAGA,CAACA,EAAEA,CAACA,GAAGA,CAACA,CAACA,MAAMA,EAAEA,CAACA,EAAEA,EAAEA,CAACA;YAChCA,CAACA,CAACA,CAACA,CAACA,CAACA,KAAKA,EAAEA,CAACA;QACjBA,CAACA;IACLA,CAACA,EAnCUD,GAAGA,GAAHA,OAAGA,KAAHA,OAAGA,QAmCbA;AAADA,CAACA,EAnCM,GAAG,KAAH,GAAG,QAmCT"}
\ No newline at end of file
+{"version":3,"file":"sourceMapValidationClasses.js","sourceRoot":"","sources":["sourceMapValidationClasses.ts"],"names":["Foo","Foo.Bar","Foo.Bar.Greeter","Foo.Bar.Greeter.constructor","Foo.Bar.Greeter.greet","Foo.Bar.foo","Foo.Bar.foo2"],"mappings":"AAAA,IAAO,GAAG,CAmCT;AAnCD,WAAO,GAAG;IAACA,IAAAA,GAAGA,CAmCbA;IAnCUA,WAAAA,GAAGA,EAACA,CAACA;QACZC,YAAYA,CAACA;QAEbA,IAAMA,OAAOA;YACTC,SADEA,OAAOA,CACUA,QAAgBA;gBAAhBC,aAAQA,GAARA,QAAQA,CAAQA;YACnCA,CAACA;YAEDD,uBAAKA,GAALA;gBACIE,MAAMA,CAACA,MAAMA,GAAGA,IAAIA,CAACA,QAAQA,GAAGA,OAAOA,CAACA;YAC5CA,CAACA;YACLF,cAACA;QAADA,CAACA,AAPDD,IAOCA;QAGDA,SAASA,GAAGA,CAACA,QAAgBA;YACzBI,MAAMA,CAACA,IAAIA,OAAOA,CAACA,QAAQA,CAACA,CAACA;QACjCA,CAACA;QAEDJ,IAAIA,OAAOA,GAAGA,IAAIA,OAAOA,CAACA,eAAeA,CAACA,CAACA;QAC3CA,IAAIA,GAAGA,GAAGA,OAAOA,CAACA,KAAKA,EAAEA,CAACA;QAE1BA,SAASA,IAAIA,CAACA,QAAgBA;YAAEK,kBAAiBA,mBAAmBA,MAAUA;iBAA9CA,WAA8CA,CAA9CA,sBAA8CA,CAA9CA,IAA8CA;gBAA9CA,cAAiBA,mBAAmBA,yBAAUA;;YAC1EA,IAAIA,QAAQA,GAAcA,EAAEA,EAAEA,0BAA0BA,AAA3BA;YAC7BA,QAAQA,CAACA,CAACA,CAACA,GAAGA,IAAIA,OAAOA,CAACA,QAAQA,CAACA,CAACA;YACpCA,GAAGA,CAACA,CAACA,GAAGA,CAACA,CAACA,GAAGA,CAACA,EAAEA,CAACA,GAAGA,aAAaA,CAACA,MAAMA,EAAEA,CAACA,EAAEA,EAAEA,CAACA;gBAC5CA,QAAQA,CAACA,IAAIA,CAACA,IAAIA,OAAOA,CAACA,aAAaA,CAACA,CAACA,CAACA,CAACA,CAACA,CAACA;YACjDA,CAACA;YAEDA,MAAMA,CAACA,QAAQA,CAACA;QACpBA,CAACA;QAEDL,IAAIA,CAACA,GAAGA,IAAIA,CAACA,OAAOA,EAAEA,OAAOA,EAAEA,GAAGA,CAACA,CAACA;QAEpCA,AADAA,qCAAqCA;QACrCA,GAAGA,CAACA,CAACA,GAAGA,CAACA,CAACA,GAAGA,CAACA,EAAEA,CAACA,GAAGA,CAACA,CAACA,MAAMA,EAAEA,CAACA,EAAEA,EAAEA,CAACA;YAChCA,CAACA,CAACA,CAACA,CAACA,CAACA,KAAKA,EAAEA,CAACA;QACjBA,CAACA;IACLA,CAACA,EAnCUD,GAAGA,GAAHA,OAAGA,KAAHA,OAAGA,QAmCbA;AAADA,CAACA,EAnCM,GAAG,KAAH,GAAG,QAmCT"}
\ No newline at end of file
diff --git a/tests/baselines/reference/sourceMapValidationClasses.sourcemap.txt b/tests/baselines/reference/sourceMapValidationClasses.sourcemap.txt
index d82ac6c3e0516..6cd77b696fffc 100644
--- a/tests/baselines/reference/sourceMapValidationClasses.sourcemap.txt
+++ b/tests/baselines/reference/sourceMapValidationClasses.sourcemap.txt
@@ -433,7 +433,7 @@ sourceFile:sourceMapValidationClasses.ts
 3 >                 ^^^^
 4 >                     ^
 5 >                      ^^^^^^^^
-6 >                              ^^^^^^->
+6 >                              ^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1 >
   >
   >    
@@ -447,14 +447,20 @@ sourceFile:sourceMapValidationClasses.ts
 4 >Emitted(20, 23) Source(21, 19) + SourceIndex(0) name (Foo.Bar)
 5 >Emitted(20, 31) Source(21, 35) + SourceIndex(0) name (Foo.Bar)
 ---
->>>            var restGreetings = [];
+>>>            var restGreetings /* more greeting */ = [];
 1->^^^^^^^^^^^^
-2 >            ^^^^^^^^^^^^^^^^^^^^^^^
-3 >                                   ^^^^^^^^^^^^^^^^^^^^^^^^^->
+2 >            ^^^^^^^^^^^^^^^^^^
+3 >                              ^^^^^^^^^^^^^^^^^^^
+4 >                                                 ^^^^^^
+5 >                                                       ^^^^^->
 1->, 
-2 >            ...restGreetings /* more greeting */: string[]
+2 >            ...restGreetings 
+3 >                              /* more greeting */
+4 >                                                 : string[]
 1->Emitted(21, 13) Source(21, 37) + SourceIndex(0) name (Foo.Bar.foo2)
-2 >Emitted(21, 36) Source(21, 83) + SourceIndex(0) name (Foo.Bar.foo2)
+2 >Emitted(21, 31) Source(21, 54) + SourceIndex(0) name (Foo.Bar.foo2)
+3 >Emitted(21, 50) Source(21, 73) + SourceIndex(0) name (Foo.Bar.foo2)
+4 >Emitted(21, 56) Source(21, 83) + SourceIndex(0) name (Foo.Bar.foo2)
 ---
 >>>            for (var _i = 1; _i < arguments.length; _i++) {
 1->^^^^^^^^^^^^^^^^^
@@ -463,6 +469,7 @@ sourceFile:sourceMapValidationClasses.ts
 4 >                             ^^^^^^^^^^^^^^^^^^^^^^
 5 >                                                   ^
 6 >                                                    ^^^^
+7 >                                                        ^^^^^^^^^^^^^^^^^^^->
 1->
 2 >                 ...restGreetings /* more greeting */: string[]
 3 >                            
@@ -476,13 +483,19 @@ sourceFile:sourceMapValidationClasses.ts
 5 >Emitted(22, 53) Source(21, 37) + SourceIndex(0) name (Foo.Bar.foo2)
 6 >Emitted(22, 57) Source(21, 83) + SourceIndex(0) name (Foo.Bar.foo2)
 ---
->>>                restGreetings[_i - 1] = arguments[_i];
-1 >^^^^^^^^^^^^^^^^
-2 >                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-1 >
-2 >                ...restGreetings /* more greeting */: string[]
-1 >Emitted(23, 17) Source(21, 37) + SourceIndex(0) name (Foo.Bar.foo2)
-2 >Emitted(23, 55) Source(21, 83) + SourceIndex(0) name (Foo.Bar.foo2)
+>>>                restGreetings /* more greeting */[_i - 1] = arguments[_i];
+1->^^^^^^^^^^^^^^^^
+2 >                ^^^^^^^^^^^^^^
+3 >                              ^^^^^^^^^^^^^^^^^^^
+4 >                                                 ^^^^^^^^^^^^^^^^^^^^^^^^^
+1->
+2 >                ...restGreetings 
+3 >                              /* more greeting */
+4 >                                                 : string[]
+1->Emitted(23, 17) Source(21, 37) + SourceIndex(0) name (Foo.Bar.foo2)
+2 >Emitted(23, 31) Source(21, 54) + SourceIndex(0) name (Foo.Bar.foo2)
+3 >Emitted(23, 50) Source(21, 73) + SourceIndex(0) name (Foo.Bar.foo2)
+4 >Emitted(23, 75) Source(21, 83) + SourceIndex(0) name (Foo.Bar.foo2)
 ---
 >>>            }
 >>>            var greeters = []; /* inline block comment */
@@ -717,7 +730,7 @@ sourceFile:sourceMapValidationClasses.ts
 11>                                       ^^^
 12>                                          ^
 13>                                           ^
-14>                                            ^->
+14>                                            ^^->
 1->
   >
   >    
@@ -747,8 +760,21 @@ sourceFile:sourceMapValidationClasses.ts
 12>Emitted(32, 44) Source(31, 40) + SourceIndex(0) name (Foo.Bar)
 13>Emitted(32, 45) Source(31, 41) + SourceIndex(0) name (Foo.Bar)
 ---
->>>        for (var j = 0; j < b.length; j++) {
+>>>        // This is simple signle line comment
 1->^^^^^^^^
+2 >        
+3 >        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+1->
+  >    // This is simple signle line comment
+  >    
+2 >        
+3 >        // This is simple signle line comment
+1->Emitted(33, 9) Source(33, 5) + SourceIndex(0) name (Foo.Bar)
+2 >Emitted(33, 9) Source(32, 5) + SourceIndex(0) name (Foo.Bar)
+3 >Emitted(33, 46) Source(32, 42) + SourceIndex(0) name (Foo.Bar)
+---
+>>>        for (var j = 0; j < b.length; j++) {
+1 >^^^^^^^^
 2 >        ^^^
 3 >           ^
 4 >            ^
@@ -768,8 +794,7 @@ sourceFile:sourceMapValidationClasses.ts
 18>                                       ^^
 19>                                         ^^
 20>                                           ^
-1->
-  >    // This is simple signle line comment
+1 >
   >    
 2 >        for
 3 >            
@@ -790,26 +815,26 @@ sourceFile:sourceMapValidationClasses.ts
 18>                                       ++
 19>                                         ) 
 20>                                           {
-1->Emitted(33, 9) Source(33, 5) + SourceIndex(0) name (Foo.Bar)
-2 >Emitted(33, 12) Source(33, 8) + SourceIndex(0) name (Foo.Bar)
-3 >Emitted(33, 13) Source(33, 9) + SourceIndex(0) name (Foo.Bar)
-4 >Emitted(33, 14) Source(33, 10) + SourceIndex(0) name (Foo.Bar)
-5 >Emitted(33, 17) Source(33, 13) + SourceIndex(0) name (Foo.Bar)
-6 >Emitted(33, 18) Source(33, 14) + SourceIndex(0) name (Foo.Bar)
-7 >Emitted(33, 19) Source(33, 15) + SourceIndex(0) name (Foo.Bar)
-8 >Emitted(33, 22) Source(33, 18) + SourceIndex(0) name (Foo.Bar)
-9 >Emitted(33, 23) Source(33, 19) + SourceIndex(0) name (Foo.Bar)
-10>Emitted(33, 25) Source(33, 21) + SourceIndex(0) name (Foo.Bar)
-11>Emitted(33, 26) Source(33, 22) + SourceIndex(0) name (Foo.Bar)
-12>Emitted(33, 29) Source(33, 25) + SourceIndex(0) name (Foo.Bar)
-13>Emitted(33, 30) Source(33, 26) + SourceIndex(0) name (Foo.Bar)
-14>Emitted(33, 31) Source(33, 27) + SourceIndex(0) name (Foo.Bar)
-15>Emitted(33, 37) Source(33, 33) + SourceIndex(0) name (Foo.Bar)
-16>Emitted(33, 39) Source(33, 35) + SourceIndex(0) name (Foo.Bar)
-17>Emitted(33, 40) Source(33, 36) + SourceIndex(0) name (Foo.Bar)
-18>Emitted(33, 42) Source(33, 38) + SourceIndex(0) name (Foo.Bar)
-19>Emitted(33, 44) Source(33, 40) + SourceIndex(0) name (Foo.Bar)
-20>Emitted(33, 45) Source(33, 41) + SourceIndex(0) name (Foo.Bar)
+1 >Emitted(34, 9) Source(33, 5) + SourceIndex(0) name (Foo.Bar)
+2 >Emitted(34, 12) Source(33, 8) + SourceIndex(0) name (Foo.Bar)
+3 >Emitted(34, 13) Source(33, 9) + SourceIndex(0) name (Foo.Bar)
+4 >Emitted(34, 14) Source(33, 10) + SourceIndex(0) name (Foo.Bar)
+5 >Emitted(34, 17) Source(33, 13) + SourceIndex(0) name (Foo.Bar)
+6 >Emitted(34, 18) Source(33, 14) + SourceIndex(0) name (Foo.Bar)
+7 >Emitted(34, 19) Source(33, 15) + SourceIndex(0) name (Foo.Bar)
+8 >Emitted(34, 22) Source(33, 18) + SourceIndex(0) name (Foo.Bar)
+9 >Emitted(34, 23) Source(33, 19) + SourceIndex(0) name (Foo.Bar)
+10>Emitted(34, 25) Source(33, 21) + SourceIndex(0) name (Foo.Bar)
+11>Emitted(34, 26) Source(33, 22) + SourceIndex(0) name (Foo.Bar)
+12>Emitted(34, 29) Source(33, 25) + SourceIndex(0) name (Foo.Bar)
+13>Emitted(34, 30) Source(33, 26) + SourceIndex(0) name (Foo.Bar)
+14>Emitted(34, 31) Source(33, 27) + SourceIndex(0) name (Foo.Bar)
+15>Emitted(34, 37) Source(33, 33) + SourceIndex(0) name (Foo.Bar)
+16>Emitted(34, 39) Source(33, 35) + SourceIndex(0) name (Foo.Bar)
+17>Emitted(34, 40) Source(33, 36) + SourceIndex(0) name (Foo.Bar)
+18>Emitted(34, 42) Source(33, 38) + SourceIndex(0) name (Foo.Bar)
+19>Emitted(34, 44) Source(33, 40) + SourceIndex(0) name (Foo.Bar)
+20>Emitted(34, 45) Source(33, 41) + SourceIndex(0) name (Foo.Bar)
 ---
 >>>            b[j].greet();
 1 >^^^^^^^^^^^^
@@ -831,15 +856,15 @@ sourceFile:sourceMapValidationClasses.ts
 7 >                 greet
 8 >                      ()
 9 >                        ;
-1 >Emitted(34, 13) Source(34, 9) + SourceIndex(0) name (Foo.Bar)
-2 >Emitted(34, 14) Source(34, 10) + SourceIndex(0) name (Foo.Bar)
-3 >Emitted(34, 15) Source(34, 11) + SourceIndex(0) name (Foo.Bar)
-4 >Emitted(34, 16) Source(34, 12) + SourceIndex(0) name (Foo.Bar)
-5 >Emitted(34, 17) Source(34, 13) + SourceIndex(0) name (Foo.Bar)
-6 >Emitted(34, 18) Source(34, 14) + SourceIndex(0) name (Foo.Bar)
-7 >Emitted(34, 23) Source(34, 19) + SourceIndex(0) name (Foo.Bar)
-8 >Emitted(34, 25) Source(34, 21) + SourceIndex(0) name (Foo.Bar)
-9 >Emitted(34, 26) Source(34, 22) + SourceIndex(0) name (Foo.Bar)
+1 >Emitted(35, 13) Source(34, 9) + SourceIndex(0) name (Foo.Bar)
+2 >Emitted(35, 14) Source(34, 10) + SourceIndex(0) name (Foo.Bar)
+3 >Emitted(35, 15) Source(34, 11) + SourceIndex(0) name (Foo.Bar)
+4 >Emitted(35, 16) Source(34, 12) + SourceIndex(0) name (Foo.Bar)
+5 >Emitted(35, 17) Source(34, 13) + SourceIndex(0) name (Foo.Bar)
+6 >Emitted(35, 18) Source(34, 14) + SourceIndex(0) name (Foo.Bar)
+7 >Emitted(35, 23) Source(34, 19) + SourceIndex(0) name (Foo.Bar)
+8 >Emitted(35, 25) Source(34, 21) + SourceIndex(0) name (Foo.Bar)
+9 >Emitted(35, 26) Source(34, 22) + SourceIndex(0) name (Foo.Bar)
 ---
 >>>        }
 1 >^^^^^^^^
@@ -848,8 +873,8 @@ sourceFile:sourceMapValidationClasses.ts
 1 >
   >    
 2 >        }
-1 >Emitted(35, 9) Source(35, 5) + SourceIndex(0) name (Foo.Bar)
-2 >Emitted(35, 10) Source(35, 6) + SourceIndex(0) name (Foo.Bar)
+1 >Emitted(36, 9) Source(35, 5) + SourceIndex(0) name (Foo.Bar)
+2 >Emitted(36, 10) Source(35, 6) + SourceIndex(0) name (Foo.Bar)
 ---
 >>>    })(Bar = Foo.Bar || (Foo.Bar = {}));
 1->^^^^
@@ -906,15 +931,15 @@ sourceFile:sourceMapValidationClasses.ts
   >                                        b[j].greet();
   >                                    }
   >                                }
-1->Emitted(36, 5) Source(36, 1) + SourceIndex(0) name (Foo.Bar)
-2 >Emitted(36, 6) Source(36, 2) + SourceIndex(0) name (Foo.Bar)
-3 >Emitted(36, 8) Source(1, 12) + SourceIndex(0) name (Foo)
-4 >Emitted(36, 11) Source(1, 15) + SourceIndex(0) name (Foo)
-5 >Emitted(36, 14) Source(1, 12) + SourceIndex(0) name (Foo)
-6 >Emitted(36, 21) Source(1, 15) + SourceIndex(0) name (Foo)
-7 >Emitted(36, 26) Source(1, 12) + SourceIndex(0) name (Foo)
-8 >Emitted(36, 33) Source(1, 15) + SourceIndex(0) name (Foo)
-9 >Emitted(36, 41) Source(36, 2) + SourceIndex(0) name (Foo)
+1->Emitted(37, 5) Source(36, 1) + SourceIndex(0) name (Foo.Bar)
+2 >Emitted(37, 6) Source(36, 2) + SourceIndex(0) name (Foo.Bar)
+3 >Emitted(37, 8) Source(1, 12) + SourceIndex(0) name (Foo)
+4 >Emitted(37, 11) Source(1, 15) + SourceIndex(0) name (Foo)
+5 >Emitted(37, 14) Source(1, 12) + SourceIndex(0) name (Foo)
+6 >Emitted(37, 21) Source(1, 15) + SourceIndex(0) name (Foo)
+7 >Emitted(37, 26) Source(1, 12) + SourceIndex(0) name (Foo)
+8 >Emitted(37, 33) Source(1, 15) + SourceIndex(0) name (Foo)
+9 >Emitted(37, 41) Source(36, 2) + SourceIndex(0) name (Foo)
 ---
 >>>})(Foo || (Foo = {}));
 1 >
@@ -967,12 +992,12 @@ sourceFile:sourceMapValidationClasses.ts
   >                      b[j].greet();
   >                  }
   >              }
-1 >Emitted(37, 1) Source(36, 1) + SourceIndex(0) name (Foo)
-2 >Emitted(37, 2) Source(36, 2) + SourceIndex(0) name (Foo)
-3 >Emitted(37, 4) Source(1, 8) + SourceIndex(0)
-4 >Emitted(37, 7) Source(1, 11) + SourceIndex(0)
-5 >Emitted(37, 12) Source(1, 8) + SourceIndex(0)
-6 >Emitted(37, 15) Source(1, 11) + SourceIndex(0)
-7 >Emitted(37, 23) Source(36, 2) + SourceIndex(0)
+1 >Emitted(38, 1) Source(36, 1) + SourceIndex(0) name (Foo)
+2 >Emitted(38, 2) Source(36, 2) + SourceIndex(0) name (Foo)
+3 >Emitted(38, 4) Source(1, 8) + SourceIndex(0)
+4 >Emitted(38, 7) Source(1, 11) + SourceIndex(0)
+5 >Emitted(38, 12) Source(1, 8) + SourceIndex(0)
+6 >Emitted(38, 15) Source(1, 11) + SourceIndex(0)
+7 >Emitted(38, 23) Source(36, 2) + SourceIndex(0)
 ---
 >>>//# sourceMappingURL=sourceMapValidationClasses.js.map
\ No newline at end of file
diff --git a/tests/baselines/reference/sourceMapValidationEnums.js.map b/tests/baselines/reference/sourceMapValidationEnums.js.map
index 721e0a3b48bb4..1627788c6b6db 100644
--- a/tests/baselines/reference/sourceMapValidationEnums.js.map
+++ b/tests/baselines/reference/sourceMapValidationEnums.js.map
@@ -1,2 +1,2 @@
 //// [sourceMapValidationEnums.js.map]
-{"version":3,"file":"sourceMapValidationEnums.js","sourceRoot":"","sources":["sourceMapValidationEnums.ts"],"names":["e","e2","e3"],"mappings":"AAAA,IAAK,CAIJ;AAJD,WAAK,CAAC;IACFA,mBAACA;IACDA,mBAACA;IACDA,mBAACA;AACLA,CAACA,EAJI,CAAC,KAAD,CAAC,QAIL;AACD,IAAK,EAKJ;AALD,WAAK,EAAE;IACHC,aAAIA,EAAEA,OAAAA;IACNA,aAAIA,EAAEA,OAAAA;IACNA,sBAACA;IACDA,wBAAEA;AACNA,CAACA,EALI,EAAE,KAAF,EAAE,QAKN;AACD,IAAK,EACJ;AADD,WAAK,EAAE;AACPC,CAACA,EADI,EAAE,KAAF,EAAE,QACN"}
\ No newline at end of file
+{"version":3,"file":"sourceMapValidationEnums.js","sourceRoot":"","sources":["sourceMapValidationEnums.ts"],"names":["e","e2","e3"],"mappings":"AAAA,IAAK,CAIJ;AAJD,WAAK,CAAC;IACFA,mBAACA,CAAAA;IACDA,mBAACA,CAAAA;IACDA,mBAACA,CAAAA;AACLA,CAACA,EAJI,CAAC,KAAD,CAAC,QAIL;AACD,IAAK,EAKJ;AALD,WAAK,EAAE;IACHC,aAAIA,EAAEA,OAAAA,CAAAA;IACNA,aAAIA,EAAEA,OAAAA,CAAAA;IACNA,sBAACA,CAAAA;IACDA,wBAAEA,CAAAA;AACNA,CAACA,EALI,EAAE,KAAF,EAAE,QAKN;AACD,IAAK,EACJ;AADD,WAAK,EAAE;AACPC,CAACA,EADI,EAAE,KAAF,EAAE,QACN"}
\ No newline at end of file
diff --git a/tests/baselines/reference/sourceMapValidationEnums.sourcemap.txt b/tests/baselines/reference/sourceMapValidationEnums.sourcemap.txt
index 18148fc281b38..337aa0989d3b6 100644
--- a/tests/baselines/reference/sourceMapValidationEnums.sourcemap.txt
+++ b/tests/baselines/reference/sourceMapValidationEnums.sourcemap.txt
@@ -39,31 +39,40 @@ sourceFile:sourceMapValidationEnums.ts
 >>>    e[e["x"] = 0] = "x";
 1->^^^^
 2 >    ^^^^^^^^^^^^^^^^^^^
-3 >                       ^^->
+3 >                       ^
+4 >                        ^->
 1-> {
   >    
 2 >    x
+3 >                       
 1->Emitted(3, 5) Source(2, 5) + SourceIndex(0) name (e)
 2 >Emitted(3, 24) Source(2, 6) + SourceIndex(0) name (e)
+3 >Emitted(3, 25) Source(2, 6) + SourceIndex(0) name (e)
 ---
 >>>    e[e["y"] = 1] = "y";
 1->^^^^
 2 >    ^^^^^^^^^^^^^^^^^^^
-3 >                       ^^->
+3 >                       ^
+4 >                        ^->
 1->,
   >    
 2 >    y
+3 >                       
 1->Emitted(4, 5) Source(3, 5) + SourceIndex(0) name (e)
 2 >Emitted(4, 24) Source(3, 6) + SourceIndex(0) name (e)
+3 >Emitted(4, 25) Source(3, 6) + SourceIndex(0) name (e)
 ---
 >>>    e[e["x"] = 2] = "x";
 1->^^^^
 2 >    ^^^^^^^^^^^^^^^^^^^
+3 >                       ^
 1->,
   >    
 2 >    x
+3 >                       
 1->Emitted(5, 5) Source(4, 5) + SourceIndex(0) name (e)
 2 >Emitted(5, 24) Source(4, 6) + SourceIndex(0) name (e)
+3 >Emitted(5, 25) Source(4, 6) + SourceIndex(0) name (e)
 ---
 >>>})(e || (e = {}));
 1 >
@@ -128,51 +137,63 @@ sourceFile:sourceMapValidationEnums.ts
 2 >    ^^^^^^^^^^^^^
 3 >                 ^^
 4 >                   ^^^^^^^
-5 >                          ^^->
+5 >                          ^
+6 >                           ^->
 1-> {
   >    
 2 >    x = 
 3 >                 10
 4 >                   
+5 >                          
 1->Emitted(9, 5) Source(7, 5) + SourceIndex(0) name (e2)
 2 >Emitted(9, 18) Source(7, 9) + SourceIndex(0) name (e2)
 3 >Emitted(9, 20) Source(7, 11) + SourceIndex(0) name (e2)
 4 >Emitted(9, 27) Source(7, 11) + SourceIndex(0) name (e2)
+5 >Emitted(9, 28) Source(7, 11) + SourceIndex(0) name (e2)
 ---
 >>>    e2[e2["y"] = 10] = "y";
 1->^^^^
 2 >    ^^^^^^^^^^^^^
 3 >                 ^^
 4 >                   ^^^^^^^
-5 >                          ^^->
+5 >                          ^
+6 >                           ^->
 1->,
   >    
 2 >    y = 
 3 >                 10
 4 >                   
+5 >                          
 1->Emitted(10, 5) Source(8, 5) + SourceIndex(0) name (e2)
 2 >Emitted(10, 18) Source(8, 9) + SourceIndex(0) name (e2)
 3 >Emitted(10, 20) Source(8, 11) + SourceIndex(0) name (e2)
 4 >Emitted(10, 27) Source(8, 11) + SourceIndex(0) name (e2)
+5 >Emitted(10, 28) Source(8, 11) + SourceIndex(0) name (e2)
 ---
 >>>    e2[e2["z"] = 11] = "z";
 1->^^^^
 2 >    ^^^^^^^^^^^^^^^^^^^^^^
-3 >                          ^^^^->
+3 >                          ^
+4 >                           ^^^->
 1->,
   >    
 2 >    z
+3 >                          
 1->Emitted(11, 5) Source(9, 5) + SourceIndex(0) name (e2)
 2 >Emitted(11, 27) Source(9, 6) + SourceIndex(0) name (e2)
+3 >Emitted(11, 28) Source(9, 6) + SourceIndex(0) name (e2)
 ---
 >>>    e2[e2["x2"] = 12] = "x2";
 1->^^^^
 2 >    ^^^^^^^^^^^^^^^^^^^^^^^^
+3 >                            ^
 1->,
   >    
 2 >    x2
+3 >                            
 1->Emitted(12, 5) Source(10, 5) + SourceIndex(0) name (e2)
 2 >Emitted(12, 29) Source(10, 7) + SourceIndex(0) name (e2)
+3 >Emitted(12, 30) Source(10, 7) + SourceIndex(0) name (e2)
 ---
 >>>})(e2 || (e2 = {}));
 1 >
diff --git a/tests/baselines/reference/switchAssignmentCompat.js b/tests/baselines/reference/switchAssignmentCompat.js
index 7b3f2af80bb22..1e6792ee378a5 100644
--- a/tests/baselines/reference/switchAssignmentCompat.js
+++ b/tests/baselines/reference/switchAssignmentCompat.js
@@ -13,5 +13,5 @@ var Foo = (function () {
     return Foo;
 })();
 switch (0) {
-    case Foo: break;
+    case Foo: break; // Error expected
 }
diff --git a/tests/baselines/reference/switchCasesExpressionTypeMismatch.js b/tests/baselines/reference/switchCasesExpressionTypeMismatch.js
index a35dc633e35b8..ca354779be1a5 100644
--- a/tests/baselines/reference/switchCasesExpressionTypeMismatch.js
+++ b/tests/baselines/reference/switchCasesExpressionTypeMismatch.js
@@ -25,12 +25,13 @@ var Foo = (function () {
     return Foo;
 })();
 switch (0) {
-    case Foo: break;
-    case "sss": break;
-    case 123: break;
-    case true: break;
+    case Foo: break; // Error
+    case "sss": break; // Error
+    case 123: break; // No Error
+    case true: break; // Error
 }
 var s = 0;
+// No error for all
 switch (s) {
     case Foo: break;
     case "sss": break;
diff --git a/tests/baselines/reference/throwStatements.js b/tests/baselines/reference/throwStatements.js
index 871bbc2ff0ac9..146d123279226 100644
--- a/tests/baselines/reference/throwStatements.js
+++ b/tests/baselines/reference/throwStatements.js
@@ -149,6 +149,7 @@ throw aFunctionInModule;
 // no initializer or annotation, so this is an 'any'
 var x;
 throw x;
+// literals
 throw 0.0;
 throw false;
 throw null;
diff --git a/tests/baselines/reference/typeGuardsInConditionalExpression.js b/tests/baselines/reference/typeGuardsInConditionalExpression.js
index 303a27dc9388c..ebe84879d2b1b 100644
--- a/tests/baselines/reference/typeGuardsInConditionalExpression.js
+++ b/tests/baselines/reference/typeGuardsInConditionalExpression.js
@@ -105,56 +105,73 @@ function foo12(x: number | string | boolean) {
 // the type of a variable or parameter is narrowed by any type guard in the condition when false, 
 // provided the false expression contains no assignments to the variable or parameter.
 function foo(x) {
-    return typeof x === "string" ? x.length : x++; // number
+    return typeof x === "string" ? x.length // string
+     : x++; // number
 }
 function foo2(x) {
     // x is assigned in the if true branch, the type is not narrowed
-    return typeof x === "string" ? (x = 10 && x) : x; // string | number
+    return typeof x === "string" ? (x = 10 && x) // string | number
+     : x; // string | number
 }
 function foo3(x) {
     // x is assigned in the if false branch, the type is not narrowed
     // even though assigned using same type as narrowed expression
-    return typeof x === "string" ? (x = "Hello" && x) : x; // string | number
+    return typeof x === "string" ? (x = "Hello" && x) // string | number
+     : x; // string | number
 }
 function foo4(x) {
     // false branch updates the variable - so here it is not number
     // even though assigned using same type as narrowed expression
-    return typeof x === "string" ? x : (x = 10 && x); // string | number
+    return typeof x === "string" ? x // string | number
+     : (x = 10 && x); // string | number
 }
 function foo5(x) {
     // false branch updates the variable - so here it is not number
-    return typeof x === "string" ? x : (x = "hello" && x); // string | number
+    return typeof x === "string" ? x // string | number
+     : (x = "hello" && x); // string | number
 }
 function foo6(x) {
     // Modify in both branches
-    return typeof x === "string" ? (x = 10 && x) : (x = "hello" && x); // string | number
+    return typeof x === "string" ? (x = 10 && x) // string | number
+     : (x = "hello" && x); // string | number
 }
 function foo7(x) {
-    return typeof x === "string" ? x === "hello" : typeof x === "boolean" ? x : x == 10; // number
+    return typeof x === "string" ? x === "hello" // string
+     : typeof x === "boolean" ? x // boolean
+     : x == 10; // number
 }
 function foo8(x) {
     var b;
-    return typeof x === "string" ? x === "hello" : ((b = x) && (typeof x === "boolean" ? x : x == 10)); // number
+    return typeof x === "string" ? x === "hello" : ((b = x) && (typeof x === "boolean" ? x // boolean
+     : x == 10)); // number
 }
 function foo9(x) {
     var y = 10;
     // usage of x or assignment to separate variable shouldn't cause narrowing of type to stop
-    return typeof x === "string" ? ((y = x.length) && x === "hello") : x === 10; // number
+    return typeof x === "string" ? ((y = x.length) && x === "hello") // string
+     : x === 10; // number
 }
 function foo10(x) {
     // Mixing typeguards
     var b;
-    return typeof x === "string" ? x : ((b = x) && typeof x === "number" && x.toString()); // x is number
+    return typeof x === "string" ? x // string
+     : ((b = x) // x is number | boolean
+     && typeof x === "number" && x.toString()); // x is number
 }
 function foo11(x) {
     // Mixing typeguards
     // Assigning value to x deep inside another guard stops narrowing of type too
     var b;
-    return typeof x === "string" ? x : ((b = x) && typeof x === "number" && (x = 10) && x); // x is number | boolean | string
+    return typeof x === "string" ? x // number | boolean | string - changed in the false branch
+     : ((b = x) // x is number | boolean | string - because the assignment changed it
+     && typeof x === "number" && (x = 10) // assignment to x
+     && x); // x is number | boolean | string
 }
 function foo12(x) {
     // Mixing typeguards
     // Assigning value to x in outer guard shouldn't stop narrowing in the inner expression
     var b;
-    return typeof x === "string" ? (x = 10 && x.toString().length) : ((b = x) && typeof x === "number" && x); // x is number
+    return typeof x === "string" ? (x = 10 && x.toString().length) // number | boolean | string - changed here
+     : ((b = x) // x is number | boolean | string  - changed in true branch
+     && typeof x === "number" && x); // x is number
 }
diff --git a/tests/baselines/reference/typeGuardsInFunctionAndModuleBlock.js b/tests/baselines/reference/typeGuardsInFunctionAndModuleBlock.js
index 317017c9accaf..239eeb4bfe7c9 100644
--- a/tests/baselines/reference/typeGuardsInFunctionAndModuleBlock.js
+++ b/tests/baselines/reference/typeGuardsInFunctionAndModuleBlock.js
@@ -84,25 +84,29 @@ module m1 {
 function foo(x) {
     return typeof x === "string" ? x : function f() {
         var b = x; // number | boolean
-        return typeof x === "boolean" ? x.toString() : x.toString(); // number
+        return typeof x === "boolean" ? x.toString() // boolean
+         : x.toString(); // number
     }();
 }
 function foo2(x) {
     return typeof x === "string" ? x : function f(a) {
         var b = x; // new scope - number | boolean
-        return typeof x === "boolean" ? x.toString() : x.toString(); // number
+        return typeof x === "boolean" ? x.toString() // boolean
+         : x.toString(); // number
     }(x); // x here is narrowed to number | boolean
 }
 function foo3(x) {
     return typeof x === "string" ? x : (function () {
         var b = x; // new scope - number | boolean
-        return typeof x === "boolean" ? x.toString() : x.toString(); // number
+        return typeof x === "boolean" ? x.toString() // boolean
+         : x.toString(); // number
     })();
 }
 function foo4(x) {
     return typeof x === "string" ? x : (function (a) {
         var b = x; // new scope - number | boolean
-        return typeof x === "boolean" ? x.toString() : x.toString(); // number
+        return typeof x === "boolean" ? x.toString() // boolean
+         : x.toString(); // number
     })(x); // x here is narrowed to number | boolean
 }
 // Type guards affect nested function expressions, but not nested function declarations
@@ -125,7 +129,8 @@ var m;
             y = x; // string;
         }
         else {
-            y = typeof x === "boolean" ? x.toString() : x.toString(); // number
+            y = typeof x === "boolean" ? x.toString() // boolean
+             : x.toString(); // number
         }
     })(m2 || (m2 = {}));
 })(m || (m = {}));
@@ -142,7 +147,8 @@ var m1;
                 y = x; // string;
             }
             else {
-                y = typeof x === "boolean" ? x.toString() : x.toString(); // number
+                y = typeof x === "boolean" ? x.toString() // boolean
+                 : x.toString(); // number
             }
         })(m3 = m2.m3 || (m2.m3 = {}));
     })(m2 || (m2 = {}));
diff --git a/tests/baselines/reference/typeGuardsInIfStatement.js b/tests/baselines/reference/typeGuardsInIfStatement.js
index 6b1fb4b062c5b..c228c038579d1 100644
--- a/tests/baselines/reference/typeGuardsInIfStatement.js
+++ b/tests/baselines/reference/typeGuardsInIfStatement.js
@@ -258,7 +258,8 @@ function foo10(x) {
     else {
         var y;
         var b = x; // number | boolean
-        return typeof x === "number" ? x === 10 : x; // x should be boolean
+        return typeof x === "number" ? x === 10 // number
+         : x; // x should be boolean
     }
 }
 function foo11(x) {
@@ -270,7 +271,13 @@ function foo11(x) {
     else {
         var y;
         var b = x; // number | boolean | string - because below we are changing value of x in if statement
-        return typeof x === "number" ? (x = 10 && x.toString()) : (y = x && x.toString());
+        return typeof x === "number" ? (
+        // change value of x
+        x = 10 && x.toString() // number | boolean | string
+        ) : (
+        // do not change value
+        y = x && x.toString() // number | boolean | string
+        );
     }
 }
 function foo12(x) {
@@ -282,6 +289,7 @@ function foo12(x) {
     else {
         x = 10;
         var b = x; // number | boolean | string
-        return typeof x === "number" ? x.toString() : x.toString(); // boolean | string
+        return typeof x === "number" ? x.toString() // number
+         : x.toString(); // boolean | string
     }
 }
diff --git a/tests/baselines/reference/typeGuardsInRightOperandOfAndAndOperator.js b/tests/baselines/reference/typeGuardsInRightOperandOfAndAndOperator.js
index 501c5d8a9f9aa..ffba829c37d7f 100644
--- a/tests/baselines/reference/typeGuardsInRightOperandOfAndAndOperator.js
+++ b/tests/baselines/reference/typeGuardsInRightOperandOfAndAndOperator.js
@@ -71,26 +71,37 @@ function foo3(x) {
     return typeof x === "string" && ((x = "hello") && x); // string | number
 }
 function foo4(x) {
-    return typeof x !== "string" && typeof x !== "number" && x; // boolean
+    return typeof x !== "string" // string | number | boolean
+     && typeof x !== "number" // number | boolean
+     && x; // boolean
 }
 function foo5(x) {
     // usage of x or assignment to separate variable shouldn't cause narrowing of type to stop
     var b;
-    return typeof x !== "string" && ((b = x) && (typeof x !== "number" && x)); // boolean
+    return typeof x !== "string" // string | number | boolean
+     && ((b = x) && (typeof x !== "number" // number | boolean
+     && x)); // boolean
 }
 function foo6(x) {
     // Mixing typeguard narrowing in if statement with conditional expression typeguard
-    return typeof x !== "string" && (typeof x !== "number" ? x : x === 10); // number 
+    return typeof x !== "string" // string | number | boolean
+     && (typeof x !== "number" // number | boolean
+     ? x // boolean
+     : x === 10); // number 
 }
 function foo7(x) {
     var y;
     var z;
     // Mixing typeguard narrowing
     // Assigning value to x deep inside another guard stops narrowing of type too
-    return typeof x !== "string" && ((z = x) && (typeof x === "number" ? (x = 10 && x.toString()) : (y = x && x.toString()))); // number | boolean | string
+    return typeof x !== "string" && ((z = x) // string | number | boolean - x changed deeper in conditional expression
+     && (typeof x === "number" ? (x = 10 && x.toString()) // number | boolean | string
+     : (y = x && x.toString()))); // number | boolean | string
 }
 function foo8(x) {
     // Mixing typeguard 
     // Assigning value to x in outer guard shouldn't stop narrowing in the inner expression
-    return typeof x !== "string" && (x = 10) && (typeof x === "number" ? x : x.length); // string
+    return typeof x !== "string" && (x = 10) // change x - number| string
+     && (typeof x === "number" ? x // number
+     : x.length); // string
 }
diff --git a/tests/baselines/reference/typeGuardsInRightOperandOfOrOrOperator.js b/tests/baselines/reference/typeGuardsInRightOperandOfOrOrOperator.js
index d2b7938a9ca36..5f5880a49479c 100644
--- a/tests/baselines/reference/typeGuardsInRightOperandOfOrOrOperator.js
+++ b/tests/baselines/reference/typeGuardsInRightOperandOfOrOrOperator.js
@@ -71,26 +71,37 @@ function foo3(x) {
     return typeof x !== "string" || ((x = "hello") || x); // string | number
 }
 function foo4(x) {
-    return typeof x === "string" || typeof x === "number" || x; // boolean
+    return typeof x === "string" // string | number | boolean
+     || typeof x === "number" // number | boolean
+     || x; // boolean
 }
 function foo5(x) {
     // usage of x or assignment to separate variable shouldn't cause narrowing of type to stop
     var b;
-    return typeof x === "string" || ((b = x) || (typeof x === "number" || x)); // boolean
+    return typeof x === "string" // string | number | boolean
+     || ((b = x) || (typeof x === "number" // number | boolean
+     || x)); // boolean
 }
 function foo6(x) {
     // Mixing typeguard
-    return typeof x === "string" || (typeof x !== "number" ? x : x === 10); // number 
+    return typeof x === "string" // string | number | boolean
+     || (typeof x !== "number" // number | boolean
+     ? x // boolean
+     : x === 10); // number 
 }
 function foo7(x) {
     var y;
     var z;
     // Mixing typeguard narrowing
     // Assigning value to x deep inside another guard stops narrowing of type too
-    return typeof x === "string" || ((z = x) || (typeof x === "number" ? (x = 10 && x.toString()) : (y = x && x.toString()))); // number | boolean | string
+    return typeof x === "string" || ((z = x) // string | number | boolean - x changed deeper in conditional expression
+     || (typeof x === "number" ? (x = 10 && x.toString()) // number | boolean | string
+     : (y = x && x.toString()))); // number | boolean | string
 }
 function foo8(x) {
     // Mixing typeguard 
     // Assigning value to x in outer guard shouldn't stop narrowing in the inner expression
-    return typeof x === "string" || (x = 10) || (typeof x === "number" ? x : x.length); // string
+    return typeof x === "string" || (x = 10) // change x - number| string
+     || (typeof x === "number" ? x // number
+     : x.length); // string
 }
diff --git a/tests/baselines/reference/variableDeclaratorResolvedDuringContextualTyping.js b/tests/baselines/reference/variableDeclaratorResolvedDuringContextualTyping.js
index 5196497478ec4..cddf9ebf25461 100644
--- a/tests/baselines/reference/variableDeclaratorResolvedDuringContextualTyping.js
+++ b/tests/baselines/reference/variableDeclaratorResolvedDuringContextualTyping.js
@@ -131,12 +131,12 @@ var WinJS;
 })(WinJS || (WinJS = {}));
 var Errors;
 (function (Errors) {
-    var ConnectionError = (function () {
-        function ConnectionError(request) {
+    var ConnectionError /* extends Error */ = (function () {
+        function ConnectionError /* extends Error */(request) {
         }
-        return ConnectionError;
+        return ConnectionError /* extends Error */;
     })();
-    Errors.ConnectionError = ConnectionError;
+    Errors.ConnectionError /* extends Error */ = ConnectionError /* extends Error */;
 })(Errors || (Errors = {}));
 var FileService = (function () {
     function FileService() {