List.MaximumItem breaks on mixed input

[sunfield]

Dynamo version

2.0.1.5055

Operating system

Windows 10

What did you do?

Took a list of numbers from a file (so as strings), sorted and converted to number, then tried to find the largest one using List.MaximumItem.

What did you expect to see?

The largest value in the list returned.

What did you see instead?

null, with a warning.

Boiled it down to this:

Tests reveal that if some numbers have a decimal separator and others don't, then the output from String.ToNumber is not uniform, which causes problems when using List.MaximumItem, which apparently cannot handle a list that includes e.g. Int and Double.
There is actually test code for this which I imagine should have picked this up:

Dynamo/test/Libraries/CoreNodesTests/ListTests.cs

Line 364 in dec6240

Assert.AreEqual(66, List.MaximumItem(new List<object> { 8.223, 4, 0.64, 66, 10.2 }));

What's interesting, looking at the source, is that the Max() method, which List.MaximumItem uses, seems to cast its inputs to doubles. My C# is rusty but I'm feel like this should be working?

Dynamo/src/Libraries/CoreNodes/List.cs

Line 397 in 852ae53

return list.Max<object, object>(DoubleConverter);

Dynamo/src/Libraries/CoreNodes/Math.cs

Line 398 in 852ae53

public static double Max(double value1, double value2)

Looking into the DoubleConverter reveals that this was added to fix exactly this problem here #2041, which maybe it did, but perhaps got unfixed with an update..? I'm in over my head at this point, though.

[jnealb]

@sunfield Thank you for this report. We have filed it as QNTM-4876 and it is in the 2.1 backlog.

[aparajit-pratap]

@sunfield thanks for highlighting the issue and fix :)
#9012