michael@0: /*
michael@0:  * Any copyright is dedicated to the Public Domain.
michael@0:  * http://creativecommons.org/licenses/publicdomain/
michael@0:  * Contributor:
michael@0:  *   Jeff Walden <jwalden+code@mit.edu>
michael@0:  */
michael@0: 
michael@0: //-----------------------------------------------------------------------------
michael@0: var BUGNUMBER = 858381;
michael@0: var summary =
michael@0:   "Array length setting/truncating with non-dense, indexed elements";
michael@0: 
michael@0: print(BUGNUMBER + ": " + summary);
michael@0: 
michael@0: /**************
michael@0:  * BEGIN TEST *
michael@0:  **************/
michael@0: 
michael@0: function testTruncateDenseAndSparse()
michael@0: {
michael@0:   var arr;
michael@0: 
michael@0:   // initialized length 16, capacity same
michael@0:   arr = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15];
michael@0: 
michael@0:   // plus a sparse element
michael@0:   arr[987654321] = 987654321;
michael@0: 
michael@0:   // lop off the sparse element and half the dense elements, shrink capacity
michael@0:   arr.length = 8;
michael@0: 
michael@0:   assertEq(987654321 in arr, false);
michael@0:   assertEq(arr[987654321], undefined);
michael@0:   assertEq(arr.length, 8);
michael@0: }
michael@0: testTruncateDenseAndSparse();
michael@0: 
michael@0: function testTruncateSparse()
michael@0: {
michael@0:   // initialized length 8, capacity same
michael@0:   var arr = [0, 1, 2, 3, 4, 5, 6, 7];
michael@0: 
michael@0:   // plus a sparse element
michael@0:   arr[987654321] = 987654321;
michael@0: 
michael@0:   // lop off the sparse element, leave initialized length/capacity unchanged
michael@0:   arr.length = 8;
michael@0: 
michael@0:   assertEq(987654321 in arr, false);
michael@0:   assertEq(arr[987654321], undefined);
michael@0:   assertEq(arr.length, 8);
michael@0: }
michael@0: testTruncateSparse();
michael@0: 
michael@0: function testTruncateDenseAndSparseShrinkCapacity()
michael@0: {
michael@0:   // initialized length 11, capacity...somewhat larger, likely 16
michael@0:   var arr = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
michael@0: 
michael@0:   // plus a sparse element
michael@0:   arr[987654321] = 987654321;
michael@0: 
michael@0:   // lop off the sparse element, reduce initialized length, reduce capacity
michael@0:   arr.length = 8;
michael@0: 
michael@0:   assertEq(987654321 in arr, false);
michael@0:   assertEq(arr[987654321], undefined);
michael@0:   assertEq(arr.length, 8);
michael@0: }
michael@0: testTruncateDenseAndSparseShrinkCapacity();
michael@0: 
michael@0: function testTruncateSparseShrinkCapacity()
michael@0: {
michael@0:   // initialized length 8, capacity same
michael@0:   var arr = [0, 1, 2, 3, 4, 5, 6, 7];
michael@0: 
michael@0:   // capacity expands to accommodate, initialized length remains same (not equal
michael@0:   // to capacity or length)
michael@0:   arr[15] = 15;
michael@0: 
michael@0:   // now no elements past initialized length
michael@0:   delete arr[15];
michael@0: 
michael@0:   // ...except a sparse element
michael@0:   arr[987654321] = 987654321;
michael@0: 
michael@0:   // trims sparse element, doesn't change initialized length, shrinks capacity
michael@0:   arr.length = 8;
michael@0: 
michael@0:   assertEq(987654321 in arr, false);
michael@0:   assertEq(arr[987654321], undefined);
michael@0:   assertEq(arr.length, 8);
michael@0: }
michael@0: testTruncateSparseShrinkCapacity();
michael@0: 
michael@0: /******************************************************************************/
michael@0: 
michael@0: if (typeof reportCompare === "function")
michael@0:   reportCompare(true, true);
michael@0: 
michael@0: print("Tests complete");