Bug 94459 [Undo] - should refactoring undo work when text undo limit is 0?
Refactoring undos are not showing up in the package explorer undo menu when the text undo limit is set to 0. Technically the refactoring operation should be permitted on the workspace undo context history. The history should just be removing the text context from the operation. One could argue this is a correctly working "feature" but need to check why it's happening and resolve the behavior as a bug or document as expected outcome.
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/DefaultOperationHistory.java
/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.core.commands.operations.IOperationHistory#operationChanged(org.eclipse.core.commands.operations.IUndoableOperation)
	 */
	public void operationChanged(IUndoableOperation operation) {
		if (undoList.contains(operation) || redoList.contains(operation)) {
			notifyChanged(operation);
		}
	}
	/*
	 * Handle an exception that occurred while sending a notification about
	 * something happening in the operation history. When notifications fail,
	 * execution should continue, but the exception should be logged.
	 */
	private void handleNotificationException(Throwable e) {
		if (e instanceof OperationCanceledException)
			return;
		
		
		if (DEBUG_OPERATION_HISTORY_UNEXPECTED) {
			System.out
					.print("OPERATIONHISTORY >>> Exception during notification callback ");  
			System.out.print(e);
			System.out.println();
		}
		e.printStackTrace();
	}
}