in the C# version, I'm getting an error on the following 2 tests

input
*..
.**
**.

calculated result
.*.
..*
***

and

input
***...*.
*......*
.*...***

calculated result
.*......
**......
*.*..*.*
......**
......*.

Both of which seem correct?

looking at the test result, something funky is going on with the test I think

Test Failed
  Output doesn't match expected
  Expected and actual are both <System.Int32[3,3]>
  Values differ at index [0,0]
  Expected: 0
  But was:  1

and the final return in the function

    Console.WriteLine(result[0,0]);
    return result;

Prints

0

so the result coming back from the function at 0,0 is 0, but the test is seeing 1 for some reason

this will be horrible performance, imagine the the IEnumerable is a generator that generates trillions and trillions of numbers.

it really should have a failing test on memory allocation with some IEnumberable the generates billions of values.

surprising how many people seem to be copying the "DataTable" compute answer in C#, which fails the rules of Fluent Interfaces (which I'm guessing they don't have a test to assert that the properties don't exist on the result of numbers and operators )