diff --git a/tests/baselines/reference/castingTuple.errors.txt b/tests/baselines/reference/castingTuple.errors.txt
index f4efed6f1d1..98be259964d 100644
--- a/tests/baselines/reference/castingTuple.errors.txt
+++ b/tests/baselines/reference/castingTuple.errors.txt
@@ -2,19 +2,19 @@ tests/cases/conformance/types/tuple/castingTuple.ts(13,23): error TS2352: Neithe
   Property '2' is missing in type '[number, string]'.
 tests/cases/conformance/types/tuple/castingTuple.ts(16,21): error TS2352: Neither type '[C, D]' nor type '[C, D, A]' is assignable to the other.
   Property '2' is missing in type '[C, D]'.
-tests/cases/conformance/types/tuple/castingTuple.ts(24,10): error TS2352: Neither type '[number, string]' nor type '[number, number]' is assignable to the other.
+tests/cases/conformance/types/tuple/castingTuple.ts(28,10): error TS2352: Neither type '[number, string]' nor type '[number, number]' is assignable to the other.
   Types of property '1' are incompatible.
     Type 'string' is not assignable to type 'number'.
-tests/cases/conformance/types/tuple/castingTuple.ts(25,10): error TS2352: Neither type '[C, D]' nor type '[A, I]' is assignable to the other.
+tests/cases/conformance/types/tuple/castingTuple.ts(29,10): error TS2352: Neither type '[C, D]' nor type '[A, I]' is assignable to the other.
   Types of property '0' are incompatible.
     Type 'C' is not assignable to type 'A'.
-tests/cases/conformance/types/tuple/castingTuple.ts(26,5): error TS2403: Subsequent variable declarations must have the same type.  Variable 'array1' must be of type '{}[]', but here has type 'number[]'.
-tests/cases/conformance/types/tuple/castingTuple.ts(26,14): error TS2352: Neither type '[number, string]' nor type 'number[]' is assignable to the other.
+tests/cases/conformance/types/tuple/castingTuple.ts(30,5): error TS2403: Subsequent variable declarations must have the same type.  Variable 'array1' must be of type '{}[]', but here has type 'number[]'.
+tests/cases/conformance/types/tuple/castingTuple.ts(30,14): error TS2352: Neither type '[number, string]' nor type 'number[]' is assignable to the other.
   Types of property 'pop' are incompatible.
     Type '() => string | number' is not assignable to type '() => number'.
       Type 'string | number' is not assignable to type 'number'.
         Type 'string' is not assignable to type 'number'.
-tests/cases/conformance/types/tuple/castingTuple.ts(27,1): error TS2304: Cannot find name 't4'.
+tests/cases/conformance/types/tuple/castingTuple.ts(31,1): error TS2304: Cannot find name 't4'.
 
 
 ==== tests/cases/conformance/types/tuple/castingTuple.ts (7 errors) ====
@@ -41,10 +41,14 @@ tests/cases/conformance/types/tuple/castingTuple.ts(27,1): error TS2304: Cannot
 !!! error TS2352: Neither type '[C, D]' nor type '[C, D, A]' is assignable to the other.
 !!! error TS2352:   Property '2' is missing in type '[C, D]'.
     var eleFromCDA1 = classCDATuple[2]; // A
-    var eleFromCDA2 = classCDATuple[5]; // {}
+    var eleFromCDA2 = classCDATuple[5]; // C | D | A
     var t10: [E1, E2] = [E1.one, E2.one];
     var t11 = <[number, number]>t10;
     var array1 = <{}[]>emptyObjTuple;
+    var unionTuple: [C, string | number] = [new C(), "foo"];
+    var unionTuple2: [C, string | number, D] = [new C(), "foo", new D()];
+    var unionTuple3: [number, string| number] = [10, "foo"]; 
+    var unionTuple4 = <[number, number]>unionTuple3; 
     
     // error
     var t3 = <[number, number]>numStrTuple;
@@ -68,4 +72,5 @@ tests/cases/conformance/types/tuple/castingTuple.ts(27,1): error TS2304: Cannot
 !!! error TS2352:         Type 'string' is not assignable to type 'number'.
     t4[2] = 10;
     ~~
-!!! error TS2304: Cannot find name 't4'.
\ No newline at end of file
+!!! error TS2304: Cannot find name 't4'.
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/castingTuple.js b/tests/baselines/reference/castingTuple.js
index 0671062bb4e..fffadcbc070 100644
--- a/tests/baselines/reference/castingTuple.js
+++ b/tests/baselines/reference/castingTuple.js
@@ -16,16 +16,21 @@ var classCDTuple: [C, D] = [new C(), new D()];
 var interfaceIITuple = <[I, I]>classCDTuple;
 var classCDATuple = <[C, D, A]>classCDTuple;
 var eleFromCDA1 = classCDATuple[2]; // A
-var eleFromCDA2 = classCDATuple[5]; // {}
+var eleFromCDA2 = classCDATuple[5]; // C | D | A
 var t10: [E1, E2] = [E1.one, E2.one];
 var t11 = <[number, number]>t10;
 var array1 = <{}[]>emptyObjTuple;
+var unionTuple: [C, string | number] = [new C(), "foo"];
+var unionTuple2: [C, string | number, D] = [new C(), "foo", new D()];
+var unionTuple3: [number, string| number] = [10, "foo"]; 
+var unionTuple4 = <[number, number]>unionTuple3; 
 
 // error
 var t3 = <[number, number]>numStrTuple;
 var t9 = <[A, I]>classCDTuple;
 var array1 = <number[]>numStrTuple;
-t4[2] = 10;
+t4[2] = 10;
+
 
 //// [castingTuple.js]
 var __extends = this.__extends || function (d, b) {
@@ -84,10 +89,14 @@ var classCDTuple = [new C(), new D()];
 var interfaceIITuple = classCDTuple;
 var classCDATuple = classCDTuple;
 var eleFromCDA1 = classCDATuple[2]; // A
-var eleFromCDA2 = classCDATuple[5]; // {}
+var eleFromCDA2 = classCDATuple[5]; // C | D | A
 var t10 = [0 /* one */, 0 /* one */];
 var t11 = t10;
 var array1 = emptyObjTuple;
+var unionTuple = [new C(), "foo"];
+var unionTuple2 = [new C(), "foo", new D()];
+var unionTuple3 = [10, "foo"];
+var unionTuple4 = unionTuple3;
 // error
 var t3 = numStrTuple;
 var t9 = classCDTuple;
diff --git a/tests/baselines/reference/contextualTypeWithTuple.errors.txt b/tests/baselines/reference/contextualTypeWithTuple.errors.txt
index d093e176455..32e368b0f88 100644
--- a/tests/baselines/reference/contextualTypeWithTuple.errors.txt
+++ b/tests/baselines/reference/contextualTypeWithTuple.errors.txt
@@ -4,21 +4,27 @@ tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts(3,5): error TS232
       Type 'string | number | boolean' is not assignable to type 'string | number'.
         Type 'boolean' is not assignable to type 'string | number'.
           Type 'boolean' is not assignable to type 'number'.
-tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts(8,1): error TS2323: Type '[number, string, boolean]' is not assignable to type '[number, string]'.
-tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts(11,1): error TS2323: Type '[{}, number]' is not assignable to type '[{ a: string; }, number]'.
+tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts(15,1): error TS2323: Type '[number, string, boolean]' is not assignable to type '[number, string]'.
+tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts(18,1): error TS2323: Type '[{}, number]' is not assignable to type '[{ a: string; }, number]'.
   Types of property '0' are incompatible.
     Type '{}' is not assignable to type '{ a: string; }'.
       Property 'a' is missing in type '{}'.
-tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts(12,1): error TS2323: Type '[number, string]' is not assignable to type '[number, string, boolean]'.
+tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts(19,1): error TS2323: Type '[number, string]' is not assignable to type '[number, string, boolean]'.
   Property '2' is missing in type '[number, string]'.
-tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts(13,5): error TS2323: Type '[string, string, number]' is not assignable to type '[string, string]'.
+tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts(20,5): error TS2323: Type '[string, string, number]' is not assignable to type '[string, string]'.
   Types of property 'pop' are incompatible.
     Type '() => string | number' is not assignable to type '() => string'.
       Type 'string | number' is not assignable to type 'string'.
         Type 'number' is not assignable to type 'string'.
+tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts(24,1): error TS2323: Type '[C, string | number]' is not assignable to type '[C, string | number, D]'.
+  Property '2' is missing in type '[C, string | number]'.
+tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts(25,1): error TS2323: Type '[number, string | number]' is not assignable to type '[number, string]'.
+  Types of property '1' are incompatible.
+    Type 'string | number' is not assignable to type 'string'.
+      Type 'number' is not assignable to type 'string'.
 
 
-==== tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts (5 errors) ====
+==== tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts (7 errors) ====
     // no error
     var numStrTuple: [number, string] = [5, "hello"];
     var numStrTuple2: [number, string] = [5, "foo", true];
@@ -32,6 +38,13 @@ tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts(13,5): error TS23
     var numStrBoolTuple: [number, string, boolean] = [5, "foo", true];
     var objNumTuple: [{ a: string }, number] = [{ a: "world" }, 5];
     var strTupleTuple: [string, [number, {}]] = ["bar", [5, { x: 1, y: 1 }]];
+    class C { }
+    class D { }
+    var unionTuple: [C, string | number] = [new C(), "foo"];
+    var unionTuple1: [C, string | number] = [new C(), "foo"];
+    var unionTuple2: [C, string | number, D] = [new C(), "foo", new D()];
+    var unionTuple3: [number, string| number] = [10, "foo"]; 
+    
     numStrTuple = numStrTuple2;
     numStrTuple = numStrBoolTuple;
     ~~~~~~~~~~~
@@ -55,4 +68,16 @@ tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts(13,5): error TS23
 !!! error TS2323:     Type '() => string | number' is not assignable to type '() => string'.
 !!! error TS2323:       Type 'string | number' is not assignable to type 'string'.
 !!! error TS2323:         Type 'number' is not assignable to type 'string'.
-    
\ No newline at end of file
+    
+    unionTuple = unionTuple1;
+    unionTuple = unionTuple2;
+    unionTuple2 = unionTuple;
+    ~~~~~~~~~~~
+!!! error TS2323: Type '[C, string | number]' is not assignable to type '[C, string | number, D]'.
+!!! error TS2323:   Property '2' is missing in type '[C, string | number]'.
+    numStrTuple = unionTuple3;
+    ~~~~~~~~~~~
+!!! error TS2323: Type '[number, string | number]' is not assignable to type '[number, string]'.
+!!! error TS2323:   Types of property '1' are incompatible.
+!!! error TS2323:     Type 'string | number' is not assignable to type 'string'.
+!!! error TS2323:       Type 'number' is not assignable to type 'string'.
\ No newline at end of file
diff --git a/tests/baselines/reference/contextualTypeWithTuple.js b/tests/baselines/reference/contextualTypeWithTuple.js
index 61a2df5d8ce..cfcdd13f7d0 100644
--- a/tests/baselines/reference/contextualTypeWithTuple.js
+++ b/tests/baselines/reference/contextualTypeWithTuple.js
@@ -5,6 +5,13 @@ var numStrTuple2: [number, string] = [5, "foo", true];
 var numStrBoolTuple: [number, string, boolean] = [5, "foo", true];
 var objNumTuple: [{ a: string }, number] = [{ a: "world" }, 5];
 var strTupleTuple: [string, [number, {}]] = ["bar", [5, { x: 1, y: 1 }]];
+class C { }
+class D { }
+var unionTuple: [C, string | number] = [new C(), "foo"];
+var unionTuple1: [C, string | number] = [new C(), "foo"];
+var unionTuple2: [C, string | number, D] = [new C(), "foo", new D()];
+var unionTuple3: [number, string| number] = [10, "foo"]; 
+
 numStrTuple = numStrTuple2;
 numStrTuple = numStrBoolTuple;
 
@@ -12,7 +19,11 @@ numStrTuple = numStrBoolTuple;
 objNumTuple = [ {}, 5];
 numStrBoolTuple = numStrTuple;
 var strStrTuple: [string, string] = ["foo", "bar", 5];
-
+
+unionTuple = unionTuple1;
+unionTuple = unionTuple2;
+unionTuple2 = unionTuple;
+numStrTuple = unionTuple3;
 
 //// [contextualTypeWithTuple.js]
 // no error
@@ -21,9 +32,27 @@ var numStrTuple2 = [5, "foo", true];
 var numStrBoolTuple = [5, "foo", true];
 var objNumTuple = [{ a: "world" }, 5];
 var strTupleTuple = ["bar", [5, { x: 1, y: 1 }]];
+var C = (function () {
+    function C() {
+    }
+    return C;
+})();
+var D = (function () {
+    function D() {
+    }
+    return D;
+})();
+var unionTuple = [new C(), "foo"];
+var unionTuple1 = [new C(), "foo"];
+var unionTuple2 = [new C(), "foo", new D()];
+var unionTuple3 = [10, "foo"];
 numStrTuple = numStrTuple2;
 numStrTuple = numStrBoolTuple;
 // error
 objNumTuple = [{}, 5];
 numStrBoolTuple = numStrTuple;
 var strStrTuple = ["foo", "bar", 5];
+unionTuple = unionTuple1;
+unionTuple = unionTuple2;
+unionTuple2 = unionTuple;
+numStrTuple = unionTuple3;
diff --git a/tests/baselines/reference/indexerWithTuple.js b/tests/baselines/reference/indexerWithTuple.js
index fc82716ba05..91d90792e6d 100644
--- a/tests/baselines/reference/indexerWithTuple.js
+++ b/tests/baselines/reference/indexerWithTuple.js
@@ -1,32 +1,65 @@
 //// [indexerWithTuple.ts]
 var strNumTuple: [string, number] = ["foo", 10]; 
 var numTupleTuple: [number, [string, number]] = [10, ["bar", 20]];
+var unionTuple1: [number, string| number] = [10, "foo"]; 
+var unionTuple2: [boolean, string| number] = [true, "foo"]; 
 
 // no error
 var idx0 = 0;
 var idx1 = 1;
 var ele10 = strNumTuple[0]; // string
 var ele11 = strNumTuple[1]; // number
-var ele12 = strNumTuple[2]; // {}
-var ele13 = strNumTuple[idx0]; // {}
-var ele14 = strNumTuple[idx1]; // {}
+var ele12 = strNumTuple[2]; // string | number
+var ele13 = strNumTuple[idx0]; // string | number
+var ele14 = strNumTuple[idx1]; // string | number
 var ele15 = strNumTuple["0"]; // string
 var ele16 = strNumTuple["1"]; // number
 var strNumTuple1 = numTupleTuple[1];  //[string, number];
-var ele17 = numTupleTuple[2]; // {}
+var ele17 = numTupleTuple[2]; // number | [string, number]
+var eleUnion10 = unionTuple1[0]; // number
+var eleUnion11 = unionTuple1[1]; // string | number
+var eleUnion12 = unionTuple1[2]; // string | number
+var eleUnion13 = unionTuple1[idx0]; // string | number
+var eleUnion14 = unionTuple1[idx1]; // string | number
+var eleUnion15 = unionTuple1["0"]; // number
+var eleUnion16 = unionTuple1["1"]; // string | number
+
+var eleUnion20 = unionTuple2[0]; // boolean
+var eleUnion21 = unionTuple2[1]; // string | number
+var eleUnion22 = unionTuple2[2]; // string | number | boolean
+var eleUnion23 = unionTuple2[idx0]; // string | number | boolean
+var eleUnion24 = unionTuple2[idx1]; // string | number | boolean
+var eleUnion25 = unionTuple2["0"]; // boolean
+var eleUnion26 = unionTuple2["1"]; // string | number
 
 //// [indexerWithTuple.js]
 var strNumTuple = ["foo", 10];
 var numTupleTuple = [10, ["bar", 20]];
+var unionTuple1 = [10, "foo"];
+var unionTuple2 = [true, "foo"];
 // no error
 var idx0 = 0;
 var idx1 = 1;
 var ele10 = strNumTuple[0]; // string
 var ele11 = strNumTuple[1]; // number
-var ele12 = strNumTuple[2]; // {}
-var ele13 = strNumTuple[idx0]; // {}
-var ele14 = strNumTuple[idx1]; // {}
+var ele12 = strNumTuple[2]; // string | number
+var ele13 = strNumTuple[idx0]; // string | number
+var ele14 = strNumTuple[idx1]; // string | number
 var ele15 = strNumTuple["0"]; // string
 var ele16 = strNumTuple["1"]; // number
 var strNumTuple1 = numTupleTuple[1]; //[string, number];
-var ele17 = numTupleTuple[2]; // {}
+var ele17 = numTupleTuple[2]; // number | [string, number]
+var eleUnion10 = unionTuple1[0]; // number
+var eleUnion11 = unionTuple1[1]; // string | number
+var eleUnion12 = unionTuple1[2]; // string | number
+var eleUnion13 = unionTuple1[idx0]; // string | number
+var eleUnion14 = unionTuple1[idx1]; // string | number
+var eleUnion15 = unionTuple1["0"]; // number
+var eleUnion16 = unionTuple1["1"]; // string | number
+var eleUnion20 = unionTuple2[0]; // boolean
+var eleUnion21 = unionTuple2[1]; // string | number
+var eleUnion22 = unionTuple2[2]; // string | number | boolean
+var eleUnion23 = unionTuple2[idx0]; // string | number | boolean
+var eleUnion24 = unionTuple2[idx1]; // string | number | boolean
+var eleUnion25 = unionTuple2["0"]; // boolean
+var eleUnion26 = unionTuple2["1"]; // string | number
diff --git a/tests/baselines/reference/indexerWithTuple.types b/tests/baselines/reference/indexerWithTuple.types
index 28053a33081..75b89ca6088 100644
--- a/tests/baselines/reference/indexerWithTuple.types
+++ b/tests/baselines/reference/indexerWithTuple.types
@@ -8,6 +8,14 @@ var numTupleTuple: [number, [string, number]] = [10, ["bar", 20]];
 >[10, ["bar", 20]] : [number, [string, number]]
 >["bar", 20] : [string, number]
 
+var unionTuple1: [number, string| number] = [10, "foo"]; 
+>unionTuple1 : [number, string | number]
+>[10, "foo"] : [number, string]
+
+var unionTuple2: [boolean, string| number] = [true, "foo"]; 
+>unionTuple2 : [boolean, string | number]
+>[true, "foo"] : [boolean, string]
+
 // no error
 var idx0 = 0;
 >idx0 : number
@@ -25,18 +33,18 @@ var ele11 = strNumTuple[1]; // number
 >strNumTuple[1] : number
 >strNumTuple : [string, number]
 
-var ele12 = strNumTuple[2]; // {}
+var ele12 = strNumTuple[2]; // string | number
 >ele12 : string | number
 >strNumTuple[2] : string | number
 >strNumTuple : [string, number]
 
-var ele13 = strNumTuple[idx0]; // {}
+var ele13 = strNumTuple[idx0]; // string | number
 >ele13 : string | number
 >strNumTuple[idx0] : string | number
 >strNumTuple : [string, number]
 >idx0 : number
 
-var ele14 = strNumTuple[idx1]; // {}
+var ele14 = strNumTuple[idx1]; // string | number
 >ele14 : string | number
 >strNumTuple[idx1] : string | number
 >strNumTuple : [string, number]
@@ -57,8 +65,82 @@ var strNumTuple1 = numTupleTuple[1];  //[string, number];
 >numTupleTuple[1] : [string, number]
 >numTupleTuple : [number, [string, number]]
 
-var ele17 = numTupleTuple[2]; // {}
+var ele17 = numTupleTuple[2]; // number | [string, number]
 >ele17 : number | [string, number]
 >numTupleTuple[2] : number | [string, number]
 >numTupleTuple : [number, [string, number]]
 
+var eleUnion10 = unionTuple1[0]; // number
+>eleUnion10 : number
+>unionTuple1[0] : number
+>unionTuple1 : [number, string | number]
+
+var eleUnion11 = unionTuple1[1]; // string | number
+>eleUnion11 : string | number
+>unionTuple1[1] : string | number
+>unionTuple1 : [number, string | number]
+
+var eleUnion12 = unionTuple1[2]; // string | number
+>eleUnion12 : string | number
+>unionTuple1[2] : string | number
+>unionTuple1 : [number, string | number]
+
+var eleUnion13 = unionTuple1[idx0]; // string | number
+>eleUnion13 : string | number
+>unionTuple1[idx0] : string | number
+>unionTuple1 : [number, string | number]
+>idx0 : number
+
+var eleUnion14 = unionTuple1[idx1]; // string | number
+>eleUnion14 : string | number
+>unionTuple1[idx1] : string | number
+>unionTuple1 : [number, string | number]
+>idx1 : number
+
+var eleUnion15 = unionTuple1["0"]; // number
+>eleUnion15 : number
+>unionTuple1["0"] : number
+>unionTuple1 : [number, string | number]
+
+var eleUnion16 = unionTuple1["1"]; // string | number
+>eleUnion16 : string | number
+>unionTuple1["1"] : string | number
+>unionTuple1 : [number, string | number]
+
+var eleUnion20 = unionTuple2[0]; // boolean
+>eleUnion20 : boolean
+>unionTuple2[0] : boolean
+>unionTuple2 : [boolean, string | number]
+
+var eleUnion21 = unionTuple2[1]; // string | number
+>eleUnion21 : string | number
+>unionTuple2[1] : string | number
+>unionTuple2 : [boolean, string | number]
+
+var eleUnion22 = unionTuple2[2]; // string | number | boolean
+>eleUnion22 : string | number | boolean
+>unionTuple2[2] : string | number | boolean
+>unionTuple2 : [boolean, string | number]
+
+var eleUnion23 = unionTuple2[idx0]; // string | number | boolean
+>eleUnion23 : string | number | boolean
+>unionTuple2[idx0] : string | number | boolean
+>unionTuple2 : [boolean, string | number]
+>idx0 : number
+
+var eleUnion24 = unionTuple2[idx1]; // string | number | boolean
+>eleUnion24 : string | number | boolean
+>unionTuple2[idx1] : string | number | boolean
+>unionTuple2 : [boolean, string | number]
+>idx1 : number
+
+var eleUnion25 = unionTuple2["0"]; // boolean
+>eleUnion25 : boolean
+>unionTuple2["0"] : boolean
+>unionTuple2 : [boolean, string | number]
+
+var eleUnion26 = unionTuple2["1"]; // string | number
+>eleUnion26 : string | number
+>unionTuple2["1"] : string | number
+>unionTuple2 : [boolean, string | number]
+
diff --git a/tests/cases/conformance/types/tuple/castingTuple.ts b/tests/cases/conformance/types/tuple/castingTuple.ts
index f154e5f00c8..cf5c58af346 100644
--- a/tests/cases/conformance/types/tuple/castingTuple.ts
+++ b/tests/cases/conformance/types/tuple/castingTuple.ts
@@ -15,13 +15,17 @@ var classCDTuple: [C, D] = [new C(), new D()];
 var interfaceIITuple = <[I, I]>classCDTuple;
 var classCDATuple = <[C, D, A]>classCDTuple;
 var eleFromCDA1 = classCDATuple[2]; // A
-var eleFromCDA2 = classCDATuple[5]; // {}
+var eleFromCDA2 = classCDATuple[5]; // C | D | A
 var t10: [E1, E2] = [E1.one, E2.one];
 var t11 = <[number, number]>t10;
 var array1 = <{}[]>emptyObjTuple;
+var unionTuple: [C, string | number] = [new C(), "foo"];
+var unionTuple2: [C, string | number, D] = [new C(), "foo", new D()];
+var unionTuple3: [number, string| number] = [10, "foo"]; 
+var unionTuple4 = <[number, number]>unionTuple3; 
 
 // error
 var t3 = <[number, number]>numStrTuple;
 var t9 = <[A, I]>classCDTuple;
 var array1 = <number[]>numStrTuple;
-t4[2] = 10;
\ No newline at end of file
+t4[2] = 10;
diff --git a/tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts b/tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts
index 7e9575d7f82..9600ebcd671 100644
--- a/tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts
+++ b/tests/cases/conformance/types/tuple/contextualTypeWithTuple.ts
@@ -4,6 +4,13 @@ var numStrTuple2: [number, string] = [5, "foo", true];
 var numStrBoolTuple: [number, string, boolean] = [5, "foo", true];
 var objNumTuple: [{ a: string }, number] = [{ a: "world" }, 5];
 var strTupleTuple: [string, [number, {}]] = ["bar", [5, { x: 1, y: 1 }]];
+class C { }
+class D { }
+var unionTuple: [C, string | number] = [new C(), "foo"];
+var unionTuple1: [C, string | number] = [new C(), "foo"];
+var unionTuple2: [C, string | number, D] = [new C(), "foo", new D()];
+var unionTuple3: [number, string| number] = [10, "foo"]; 
+
 numStrTuple = numStrTuple2;
 numStrTuple = numStrBoolTuple;
 
@@ -11,3 +18,8 @@ numStrTuple = numStrBoolTuple;
 objNumTuple = [ {}, 5];
 numStrBoolTuple = numStrTuple;
 var strStrTuple: [string, string] = ["foo", "bar", 5];
+
+unionTuple = unionTuple1;
+unionTuple = unionTuple2;
+unionTuple2 = unionTuple;
+numStrTuple = unionTuple3;
\ No newline at end of file
diff --git a/tests/cases/conformance/types/tuple/indexerWithTuple.ts b/tests/cases/conformance/types/tuple/indexerWithTuple.ts
index 0b51ecd32ee..930ca56402c 100644
--- a/tests/cases/conformance/types/tuple/indexerWithTuple.ts
+++ b/tests/cases/conformance/types/tuple/indexerWithTuple.ts
@@ -1,15 +1,32 @@
 var strNumTuple: [string, number] = ["foo", 10]; 
 var numTupleTuple: [number, [string, number]] = [10, ["bar", 20]];
+var unionTuple1: [number, string| number] = [10, "foo"]; 
+var unionTuple2: [boolean, string| number] = [true, "foo"]; 
 
 // no error
 var idx0 = 0;
 var idx1 = 1;
 var ele10 = strNumTuple[0]; // string
 var ele11 = strNumTuple[1]; // number
-var ele12 = strNumTuple[2]; // {}
-var ele13 = strNumTuple[idx0]; // {}
-var ele14 = strNumTuple[idx1]; // {}
+var ele12 = strNumTuple[2]; // string | number
+var ele13 = strNumTuple[idx0]; // string | number
+var ele14 = strNumTuple[idx1]; // string | number
 var ele15 = strNumTuple["0"]; // string
 var ele16 = strNumTuple["1"]; // number
 var strNumTuple1 = numTupleTuple[1];  //[string, number];
-var ele17 = numTupleTuple[2]; // {}
\ No newline at end of file
+var ele17 = numTupleTuple[2]; // number | [string, number]
+var eleUnion10 = unionTuple1[0]; // number
+var eleUnion11 = unionTuple1[1]; // string | number
+var eleUnion12 = unionTuple1[2]; // string | number
+var eleUnion13 = unionTuple1[idx0]; // string | number
+var eleUnion14 = unionTuple1[idx1]; // string | number
+var eleUnion15 = unionTuple1["0"]; // number
+var eleUnion16 = unionTuple1["1"]; // string | number
+
+var eleUnion20 = unionTuple2[0]; // boolean
+var eleUnion21 = unionTuple2[1]; // string | number
+var eleUnion22 = unionTuple2[2]; // string | number | boolean
+var eleUnion23 = unionTuple2[idx0]; // string | number | boolean
+var eleUnion24 = unionTuple2[idx1]; // string | number | boolean
+var eleUnion25 = unionTuple2["0"]; // boolean
+var eleUnion26 = unionTuple2["1"]; // string | number
\ No newline at end of file