This tests that 'Selection' methods throw exceptions with reasonable messages. On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". PASS getSelection().collapse(document.documentElement, -1) threw exception IndexSizeError: Failed to execute 'collapse' on 'Selection': -1 is not a valid offset.. PASS getSelection().collapseToStart() threw exception InvalidStateError: Failed to execute 'collapseToStart' on 'Selection': there is no selection.. PASS getSelection().collapseToEnd() threw exception InvalidStateError: Failed to execute 'collapseToEnd' on 'Selection': there is no selection.. PASS getSelection().setBaseAndExtent(document.documentElement, -1, document.documentElement, 0) threw exception IndexSizeError: Failed to execute 'setBaseAndExtent' on 'Selection': -1 is not a valid base offset.. PASS getSelection().setBaseAndExtent(document.documentElement, 0, document.documentElement, -1) threw exception IndexSizeError: Failed to execute 'setBaseAndExtent' on 'Selection': -1 is not a valid extent offset.. PASS getSelection().collapse(document.documentElement, -1) threw exception IndexSizeError: Failed to execute 'collapse' on 'Selection': -1 is not a valid offset.. PASS getSelection().getRangeAt(-1) threw exception IndexSizeError: Failed to execute 'getRangeAt' on 'Selection': -1 is not a valid index.. PASS getSelection().extend(0, -1) threw exception TypeError: Failed to execute 'extend' on 'Selection': parameter 1 is not of type 'Node'.. PASS getSelection().extend(document.documentElement, -1) threw exception IndexSizeError: Failed to execute 'extend' on 'Selection': -1 is not a valid offset.. PASS getSelection().extend(document.documentElement, 1000) threw exception IndexSizeError: Failed to execute 'extend' on 'Selection': 1000 is larger than the given node's length.. PASS successfullyParsed is true TEST COMPLETE