The queryable interface no longer supports slicing via Take

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    • Type: Question
    • Resolution: Works as Designed
    • Priority: Major - P3
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    • Affects Version/s: 3.2.0
    • Component/s: None
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    • Dotnet Drivers
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      3. Which versions of the driver/connector does this apply to?

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      1. What would you like to communicate to the user about this feature? 2. Would you like the user to see examples of the syntax and/or executable code and its output? 3. Which versions of the driver/connector does this apply to?
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      Summary

      As of c# driver 3.2.0, using the "Take" operator to perform a slice when querying via the queryable interface no longer works.

      How to Reproduce

      See attached for a minimal console app that reproduces the behavior. Notable lines:

      widgetBoxCollection.InsertOne(new WidgetBox([new Widget("A"), new Widget("B"), new Widget("C")]));

var lastTwoWidgets = await widgetBoxCollection.AsQueryable()
.Where(_ => true)
.SelectMany(j => j.Widgets.Take(-2))
.ToListAsync();

var lastTwoWidgets2 = (await widgetBoxCollection.AsQueryable()
.Where(_ => true)
.Select(j => j.Widgets.Take(-2))
.ToListAsync()).Single();

Console.WriteLine($"Widgets result 1: [{string.Join(",", lastTwoWidgets.Select(w => w.Name))}]");
Console.WriteLine($"Widgets result 2: [{string.Join(",", lastTwoWidgets2.Select(w => w.Name))}]");

      Output on 3.1.0:

      Widgets result 1: [B,C]
Widgets result 2: [B,C]

      Output on 3.2.0:

      Widgets result 1: []
Widgets result 2: []

        1. Program.cs
          1.0 kB

            Assignee:
            Robert Stam
            Reporter:
            Mirek Kukla
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              Created:
              Updated:
              Resolved: