[BUG] iterating over an IEnumerable<LiteFileInfo<TFileId>> errors out on the second element if the DB is opened in shared mode

[ssteiner]

For a test, I changed the connection mode for LiteDb from exclusive to shared. And then, operations on files started erroring out.

the code I'm using looks like this:

var fs = db.GetStorage<string>("audioFiles");
var files = fs.Find(u => u.Id.StartsWith(path));
foreach (var file in files)
{ // do something with file
}

this works fine if the connection mode is direct. If you then change the connection mode to shared, It fails when there's multiple files (at least two) - the first iteration works, on the second iteration gets you a LiteException with message

This engine instance already disposed

If you get a List instead of an Enumerable (var files = fs.Find(u => u.Id.StartsWith(path)).ToList();) it works even in shared mode.

I would expect the iteration to work in shared mode, too.

LiteDB version is 5.0.21 on .NET 8.0.7 on W11 Pro 2023H2

[Joy-less]

I can confirm, this is a really intriguing issue.

The following code gives you an error:

using LiteDatabase Database = new(new ConnectionString() {
    Filename = "Database.db",
    Connection = ConnectionType.Shared,
});
ILiteCollection<BsonDocument> Accounts = Database.GetCollection("Accounts");
foreach (BsonDocument Document in Accounts.FindAll()) {
    Accounts.Update(Document);
}
GD.Print("done");

void LiteDB.Engine.EngineState.Validate(): LiteDB.LiteException: This engine instance already disposed.

But you can remove the error by doing any of the following:

• Replace Accounts.FindAll() with Accounts.FindAll().ToList()
• Replace Connection = ConnectionType.Shared with Connection = ConnectionType.Direct
• Remove Accounts.Update(Document);