fune/browser/devtools/shared/test/unit/test_undoStack.js

87 lines
1.7 KiB
JavaScript

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* Any copyright is dedicated to the Public Domain.
http://creativecommons.org/publicdomain/zero/1.0/ */
const Cu = Components.utils;
Cu.import("resource:///modules/devtools/Undo.jsm")
const MAX_SIZE = 5;
function run_test()
{
let str = "";
let stack = new UndoStack(MAX_SIZE);
function add(ch) {
stack.do(function() {
str += ch;
}, function() {
str = str.slice(0, -1);
});
}
do_check_false(stack.canUndo());
do_check_false(stack.canRedo());
// Check adding up to the limit of the size
add("a");
do_check_true(stack.canUndo());
do_check_false(stack.canRedo());
add("b");
add("c");
add("d");
add("e");
do_check_eq(str, "abcde");
// Check a simple undo+redo
stack.undo();
do_check_eq(str, "abcd");
do_check_true(stack.canRedo());
stack.redo();
do_check_eq(str, "abcde")
do_check_false(stack.canRedo());
// Check an undo followed by a new action
stack.undo();
do_check_eq(str, "abcd");
add("q");
do_check_eq(str, "abcdq");
do_check_false(stack.canRedo());
stack.undo();
do_check_eq(str, "abcd");
stack.redo();
do_check_eq(str, "abcdq");
// Revert back to the beginning of the queue...
while (stack.canUndo()) {
stack.undo();
}
do_check_eq(str, "");
// Now put it all back....
while (stack.canRedo()) {
stack.redo();
}
do_check_eq(str, "abcdq");
// Now go over the undo limit...
add("1");
add("2");
add("3");
do_check_eq(str, "abcdq123");
// And now undoing the whole stack should only undo 5 actions.
while (stack.canUndo()) {
stack.undo();
}
do_check_eq(str, "abc");
}