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/* Any copyright is dedicated to the Public Domain.
http://creativecommons.org/publicdomain/zero/1.0/ */
"use strict";
const { UndoStack } = require("resource://devtools/client/shared/undo.js");
const MAX_SIZE = 5;
function run_test() {
let str = "";
const stack = new UndoStack(MAX_SIZE);
function add(ch) {
stack.do(
function () {
str += ch;
},
function () {
str = str.slice(0, -1);
}
);
}
Assert.ok(!stack.canUndo());
Assert.ok(!stack.canRedo());
// Check adding up to the limit of the size
add("a");
Assert.ok(stack.canUndo());
Assert.ok(!stack.canRedo());
add("b");
add("c");
add("d");
add("e");
Assert.equal(str, "abcde");
// Check a simple undo+redo
stack.undo();
Assert.equal(str, "abcd");
Assert.ok(stack.canRedo());
stack.redo();
Assert.equal(str, "abcde");
Assert.ok(!stack.canRedo());
// Check an undo followed by a new action
stack.undo();
Assert.equal(str, "abcd");
add("q");
Assert.equal(str, "abcdq");
Assert.ok(!stack.canRedo());
stack.undo();
Assert.equal(str, "abcd");
stack.redo();
Assert.equal(str, "abcdq");
// Revert back to the beginning of the queue...
while (stack.canUndo()) {
stack.undo();
}
Assert.equal(str, "");
// Now put it all back....
while (stack.canRedo()) {
stack.redo();
}
Assert.equal(str, "abcdq");
// Now go over the undo limit...
add("1");
add("2");
add("3");
Assert.equal(str, "abcdq123");
// And now undoing the whole stack should only undo 5 actions.
while (stack.canUndo()) {
stack.undo();
}
Assert.equal(str, "abc");
}
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