JSTests/ChakraCore/test/switchStatement/emptyCases.js

//-------------------------------------------------------------------------------------------------------
// Copyright (C) Microsoft. All rights reserved.
// Licensed under the MIT license. See LICENSE.txt file in the project root for full license information.
//-------------------------------------------------------------------------------------------------------

/*
***************************UNIT TEST FOR SWITCH CASE OPTIMIZATION*****************************
*   Empty case statements
*/

/*
***************************************TEST 1*****************************************
*  For empty test cases and an object present in the mid of empty test cases
*
*/

function f(x)
{
    switch(x)
    {
        case 1:
           WScript.Echo(1);
           break;
        case 2:
            WScript.Echo(2);
           break;
        case 3:
            WScript.Echo(3);
            break;
        case 4:
            WScript.Echo(4);
            break;
        // empty integer case statements intercepted by an object
        case 5:
        case 6:
        case f: // object case - optimization should break the flow here
        case 8:
        case 9:
            WScript.Echo(9);
            break;
        case f:
            WScript.Echo(10);
            break;
        case 11:
           WScript.Echo(11);
           break;
        case 12:
            WScript.Echo(12);
           break;
         //Following four case statements are empty case statements with just a single case block
         //(optimizer will generate special instructions for such kind)
        case 13:
        case 14:
        case 15:
        case 16:
            WScript.Echo(16);
            break;
        case 17:
            WScript.Echo(17);
            break;
        case 18:
            WScript.Echo(18);
            break;
        case 19:
            WScript.Echo(19);
            break;
        case 20:
            WScript.Echo(20);
        default:
            WScript.Echo('default');
            break;
    }

}

for (i = 1; i < 20; i++) {
    f(i);
}

f(100); //default
f(0);   //default

/*
*****************************************TEST 2****************************************************
*   Test for case statements values in unsorted order
*   Set of Empty case statements are placed on the top, middle and at the bottom of the switch statement
*/
function g(x)
{
    switch(x)
    {
        /*empty case statements*/
        case 20:
        case 19:
        case 18:
        case 17:
            WScript.Echo(17);
            break;
        case 16:
            WScript.Echo(16);
            break;
        case 15:
            WScript.Echo(15);
            break;
        case 14:
            WScript.Echo(14);
            break;
        case 13:
            WScript.Echo(13);
            break;
            /*empty case statements*/
        case 12:
        case 11:
        case 10:
        case 9:
            WScript.Echo(9);
           break;
        case 8:
            WScript.Echo(8);
            break;
        case 7:
            WScript.Echo(7);
            break;
        case 6:
            WScript.Echo(6);
            break;
            /*empty case statements*/
        case 5:
        case 4:
        case 3:
        case 2:
        case 1:
            /* No default statement and no break at the end of the switch */
    }

}

g(1);
g(2);
g(3);
g(4);
g(5);
g(6);
g(7);
g(8);
g(9);
g(10);
g(11);
g(12);
g(13);
g(14);
g(15);
g(16);
g(17);
g(18);
g(19);
g(20);
g(100);
g(0);

/*
********************************TEST 3********************************
** All empty case statements
*/

function h(x)
{
    switch(x)
    {
        case 1:
        case 2:
        case 3:
        case 4:
        case 5:
        case 6:
        case 7:
        case 8:
        case 9:
        case 10:
        case 11:
        case 12:
        case 13:
        case 14:
        case 15:
        case 16:
        default:
            WScript.Echo('default');
            break;
    }

}

for(i=0;i<=13;i++)
{
    h(i);
}
h('hello');

for(i=14;i<=18;i++)
{
    h(i);
}