Changeset 0ec9f5 for src/Actions/ActionHistory.cpp

Timestamp:

Apr 23, 2021, 9:02:12 PM (5 years ago)

Author:

Frederik Heber <frederik.heber@…>

Branches:

Candidate_v1.7.0, stable

Children:

0fbea3

Parents:

5061d9

git-author:

Frederik Heber <frederik.heber@…> (04/06/21 20:09:39)

git-committer:

Frederik Heber <frederik.heber@…> (04/23/21 21:02:12)

Message:

Added UndoMarkAction.

NOTE: This action is necessary as not all actions are actually recorded
in the history. For example, the UndoAction is an action that is not
pushed into the history deque and also must not as further undos would
then become impossible. There are other actions that just do output
or similar things that do not change the state.
This makes it impossible to undo back to a certain state by blindly
counting actions as one cannot know from the outside whether an action
is stateless or not.

• ActionHistory allows to mark a certain HistoryElement.
• marked element is reset when undone in history.
• marked element can be set and unset via UndoMarkAction.
• ActionQueue relays undoTillMark() to ActionHistory.
• extended UndoAction by param "till-mark" to allow step-wise undo and

undoing till the set mark.

• TESTS: added regression test case on undo-mark.

File:

• src/Actions/ActionHistory.cpp (modified) (2 diffs)

src/Actions/ActionHistory.cpp

@@ -64 +64 @@
   HistoryElement elem = history.back();
   LOG(1, "INFO: Undoing action " << elem.action->getName());
+  if ((mark != NULL) && (mark == &elem)) {
+    LOG(2, "DEBUG: Undoing marked item in ActionHistory, hence resetting mark.");
+    mark = NULL;
+  }
   history.pop_back();
   ActionState::ptr newState = elem.action->undo(elem.state);
@@ -93 +97 @@
 }
 
+void ActionHistory::setMark() {
+  mark = &(history.back());
+}
+
+void ActionHistory::unsetMark() {
+  mark = NULL;
+}
+
+void ActionHistory::undoTillMark() {
+  if (mark == NULL) {
+    undoLast();
+  } else {
+    while (mark != &(history.back()))
+      undoLast();
+  }
+}
+
 void ActionHistory::addElement(Action* action,ActionState::ptr state){
   yrotsih.clear();