Cedar Logic: Persistent Floating Representation Bug & Crash

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Hey guys! Let's dive into this pesky bug report about Cedar Logic crashing due to a persistent floating representation issue. This sounds like a real headache, so let's break it down and make sure we understand what's going on. We'll cover the bug description, how to reproduce it, the expected behavior, and some additional details provided by the user. Buckle up, it's bug-hunting time!

Bug Description

This bug centers around how Cedar Logic handles copying and pasting elements on the canvas. The main problem? When you copy and paste an object, the floating representation of that pasted data stubbornly sticks around. This persistent floating representation isn't just a visual nuisance; interacting with it in certain ways can lead to a full-blown program crash. Imagine you're working on a complex diagram, meticulously placing elements, and suddenly, bam, the whole thing goes down because of a ghost image. This is exactly the kind of frustration we want to avoid, right? So, the core issue is that after a paste operation is cancelled, the visual representation of the pasted object remains, and further actions on this lingering ghost object cause instability, ultimately crashing the program. This kind of behavior not only interrupts the workflow but also risks data loss, making it a critical issue to address. The persistence of the floating representation indicates a flaw in how the program manages object placement and cancellation, particularly concerning the visual feedback provided during the paste operation. It also suggests potential memory management issues, as the program fails to properly clear the representation after it's no longer needed. Furthermore, the crash triggered by interacting with the ghost object highlights a deeper problem in the program's state management and error handling. The program's inability to gracefully handle interactions with these remnants of cancelled operations suggests a lack of robustness, making it vulnerable to unexpected behavior and crashes. To make matters worse, the interaction between this persistent representation and the undo functionality further complicates the issue, introducing additional crash scenarios and data corruption risks. Therefore, understanding and resolving this bug is crucial for ensuring the stability and reliability of Cedar Logic.

To Reproduce

Okay, let's get our hands dirty and try to reproduce this bug. Here are the steps provided to trigger the crash. Follow these closely, and you should be able to see the issue firsthand:

  1. Place an object on the canvas: Start by adding any element to your Cedar Logic workspace. This will be our guinea pig object for the copy-paste experiment.
  2. Copy the object using ctrl+c: Select the object you just placed and hit the copy shortcut. This puts the object's data into your clipboard, ready for pasting.
  3. Move the mouse elsewhere on the canvas and paste with ctrl+v: Now, move your mouse to a different spot on the canvas – this is important! Then, use the paste shortcut. Moving the mouse makes the issue clearer, but it might happen even if you don't move it.
  4. Cancel placement with escape: After pasting, you'll see the floating representation of the object. Instead of placing it, hit the escape key to cancel the paste operation. This is where the fun begins.
  5. Bug 1: The dotted floating version will stay on the canvas: This is the first sign of trouble. The floating representation, usually indicated by dotted lines, should disappear after cancelling. But it doesn't! It sticks around at the position where your mouse was when you pasted. Move your mouse between pressing ctrl+v and escape to see this more clearly. This persistent visual element is the root cause of the problems that follow.
  6. Grab and move the floating version: Click on the ghostly floating representation and drag it around. Yes, you can actually interact with this thing that shouldn't even be there!
  7. Press ctrl+z twice: Now, hit the undo shortcut twice. This is the trigger for the big crash.
  8. Bug 2: Program hangs for a few seconds and then crashes: Boom! The program freezes, thinks for a bit, and then gives up the ghost. This is the main crash we're trying to squash. This crash indicates a severe issue in how the program handles undo operations in the presence of these lingering floating representations. The program likely tries to revert to a state that is inconsistent or invalid, leading to the crash.
  9. Alternative scenario: You can also choose to delete the floating representation at any point before the crash. However, if you do anything else in the program and then try to undo past the program state immediately before triggering bug 2, the program will still hang and crash. This shows that the underlying issue isn't just the presence of the visual element, but something deeper related to how the program manages its state and undo history.
  10. Overlapping behavior: If you don't move the mouse off the selection position before pasting, you'll see the floating representation overlap with the original, creating a red highlight. This highlights further inconsistencies in how the program handles object placement and visual feedback.
  11. Other strange behavior: Finally, if you don't move the floating representation before pressing ctrl+z, you might encounter other weirdness. This suggests that the interaction between object movement, the undo system, and the persistent floating representation is complex and riddled with potential issues.

By following these steps, you should be able to reliably trigger the crash and see the persistent floating representation bug in action. This detailed reproduction procedure is crucial for developers to understand the exact sequence of events leading to the crash, making it easier to identify and fix the underlying issue.

Expected Behavior

So, what should happen when we cancel a paste operation? Let's lay out the expected behavior to make it crystal clear.

  • Bug 1: Floating representation should disappear: When you press escape to cancel a paste, that dotted floating version should vanish into thin air. It's like saying,