Change:
} export interface IModelRegistry { <del> getModel(editorModel: IEditorModel): DirtyDiffModel | null; </del> <ins> getModel(editorModel: IEditorModel): DirtyDiffModel | undefined; </ins> } export const isDirtyDiffVisible = new RawContextKey<boolean>('dirtyDiffVisible', false);

Discussion:
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I don't know what this function does but if I comment it, there is no longer this issue and there is no apparent side-effect.

Line 1481 of I think this architecture design that involves creating new models to replace the old ones every time there is an event seems wrong and prone to cause issues like this one.
We resolve the contents of a file from disk when you click on a tab. We do that in the background without blocking the opening. We do that to ensure the latest contents are loaded from disk. As for the dirty diff decorator, moving to respective owners.
I don't quite understand what the bug is. Is there something not quite working in the product?
Thanks for your comments. I think you really do not resolve the contents from the disk when the file is large... but anyway, I don't think anyone will notice it except if digging into the code. Your solution doesn't seem elegant and seems prone to cause future problems, but I was just looking at the code and found that casually. I am not really interested. I was interested in starting a branch for visualizing very large files in a google maps way (for example for visualizing genomic data) and found that "problem". But I lost interest as the code seems quite hard to work with (too many events for my taste and I didn't find any documentation for the events). I think this issue can be closed if you are not interested. It could be interesting working on the large files navigation though if you can help me find information for not having to debug every event.
Actually my comment in was wrong: we do NOT resolve the contents of the file on disk every time but only when we think it has changed. We compare the of the file with our last state and skip resolving when the file did not advance in . But as you indicated before, this requires the model to stay in memory so that we can compare the previous state to the current one. I think you figured out that we use concept for this. But you are also right that this optimization fails to apply for the dirty decorator. I ran an experiment with clicking between 2 tabs and this is the log output: So there is evidence that the optimization is not working for git dirty diff decorators because the text file model that is used for it is disposed once we compute the next diff. If we wanted to improve this, the models would have to be kept around in memory until the tab is closed maybe.

I am pretty sure that there is also a check somewhere hidden at the end of a chain of events in which the file is not reopened even if the etag check is passed but the file is too large. But I was checking that more than a month ago and now I can't find it.
What's the best way to verify this?
Verified offline with