git subrepo clone --branch=sono6good https://github.com/essej/JUCE.git deps/juce

subrepo:
  subdir:   "deps/juce"
  merged:   "b13f9084e"
upstream:
  origin:   "https://github.com/essej/JUCE.git"
  branch:   "sono6good"
  commit:   "b13f9084e"
git-subrepo:
  version:  "0.4.3"
  origin:   "https://github.com/ingydotnet/git-subrepo.git"
  commit:   "2f68596"

deps/juce/modules/juce_data_structures/undomanager/juce_UndoableAction.h

@@ -0,0 +1,100 @@
+/*
+  ==============================================================================
+
+   This file is part of the JUCE library.
+   Copyright (c) 2020 - Raw Material Software Limited
+
+   JUCE is an open source library subject to commercial or open-source
+   licensing.
+
+   By using JUCE, you agree to the terms of both the JUCE 6 End-User License
+   Agreement and JUCE Privacy Policy (both effective as of the 16th June 2020).
+
+   End User License Agreement: www.juce.com/juce-6-licence
+   Privacy Policy: www.juce.com/juce-privacy-policy
+
+   Or: You may also use this code under the terms of the GPL v3 (see
+   www.gnu.org/licenses).
+
+   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
+   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
+   DISCLAIMED.
+
+  ==============================================================================
+*/
+
+namespace juce
+{
+
+//==============================================================================
+/**
+    Used by the UndoManager class to store an action which can be done
+    and undone.
+
+    @see UndoManager
+
+    @tags{DataStructures}
+*/
+class JUCE_API  UndoableAction
+{
+protected:
+    /** Creates an action. */
+    UndoableAction() = default;
+
+public:
+    /** Destructor. */
+    virtual ~UndoableAction() = default;
+
+    //==============================================================================
+    /** Overridden by a subclass to perform the action.
+
+        This method is called by the UndoManager, and shouldn't be used directly by
+        applications.
+
+        Be careful not to make any calls in a perform() method that could call
+        recursively back into the UndoManager::perform() method
+
+        @returns    true if the action could be performed.
+        @see UndoManager::perform
+    */
+    virtual bool perform() = 0;
+
+    /** Overridden by a subclass to undo the action.
+
+        This method is called by the UndoManager, and shouldn't be used directly by
+        applications.
+
+        Be careful not to make any calls in an undo() method that could call
+        recursively back into the UndoManager::perform() method
+
+        @returns    true if the action could be undone without any errors.
+        @see UndoManager::perform
+    */
+    virtual bool undo() = 0;
+
+    //==============================================================================
+    /** Returns a value to indicate how much memory this object takes up.
+
+        Because the UndoManager keeps a list of UndoableActions, this is used
+        to work out how much space each one will take up, so that the UndoManager
+        can work out how many to keep.
+
+        The default value returned here is 10 - units are arbitrary and
+        don't have to be accurate.
+
+        @see UndoManager::getNumberOfUnitsTakenUpByStoredCommands,
+             UndoManager::setMaxNumberOfStoredUnits
+    */
+    virtual int getSizeInUnits()    { return 10; }
+
+    /** Allows multiple actions to be coalesced into a single action object, to reduce storage space.
+
+        If possible, this method should create and return a single action that does the same job as
+        this one followed by the supplied action.
+
+        If it's not possible to merge the two actions, the method should return a nullptr.
+    */
+    virtual UndoableAction* createCoalescedAction (UndoableAction* nextAction)  { ignoreUnused (nextAction); return nullptr; }
+};
+
+} // namespace juce