LINQ All returns True if the size of the collection is 0.

[EvgenyMarchuk]

Description

I'm getting true for the zero size collection, using LINQ All to check that all items have a value

Reproduction Steps

var list = new List<string>();
var isTrue = list.All(x => x == "a");
Console.WriteLine(isTrue);

Expected behavior

False

Actual behavior

True

Regression?

No response

Known Workarounds

No response

Configuration

.net8.0.404
Win10, x64

Other information

If I'm not mistaken, the same is in .net9

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[stephentoub]

Thanks, but this is by design. Every item meets the criteria. There just aren't any items.

Per the docs:
"true if every element of the source sequence passes the test in the specified predicate, or if the sequence is empty; otherwise, false."