public boolean canExecute(jetbrains.mps.openapi.editor.EditorContext context) {
SelectionManager selectionManager =
((EditorComponent) context.getEditorComponent()).getSelectionManager();
Selection selection = selectionManager.getSelection();
if (selection instanceof SingularSelection) {
SingularSelection singularSelection = (SingularSelection) selection;
if (!expandSelection(singularSelection) && selectionManager.getSelectionStackSize() > 1) {
return true;
}
EditorCell selected = singularSelection.getEditorCell();
EditorCell nextLeaf = getNextLeaf(selected);
return nextLeaf != null && getCommonSelectableAncestor(selected, nextLeaf) != null;
}
return false;
}
private boolean expandSelection(SingularSelection selection) {
switch (selection.getSideSelectDirection()) {
case LEFT:
return mySide == CellSide.LEFT;
case RIGHT:
return mySide == CellSide.RIGHT;
}
return true;
}
public void execute(jetbrains.mps.openapi.editor.EditorContext context) {
SelectionManager selectionManager =
((EditorComponent) context.getEditorComponent()).getSelectionManager();
SingularSelection selection = (SingularSelection) selectionManager.getSelection();
if (!expandSelection(selection) && selectionManager.getSelectionStackSize() > 1) {
selectionManager.popSelection();
return;
}
EditorCell selected = selection.getEditorCell();
EditorCell nextLeaf = getNextLeaf(selected);
EditorCell cellToSelect = getCommonSelectableAncestor(selected, nextLeaf);
Selection newSelection = selectionManager.createSelection(cellToSelect);
if (newSelection instanceof SingularSelection) {
((SingularSelection) newSelection)
.setSideSelectDirection(
mySide == CellSide.LEFT ? SideSelectDirection.LEFT : SideSelectDirection.RIGHT);
}
selectionManager.pushSelection(newSelection);
}