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Votes

0

Found in

2018.3.5f1

Issue ID

1139185

Regression

Yes

Array.BinarySearch parameters get swapped from .NET 3.4 to .NET 4.0

Mono

-

Binary search gives different ordering of IComparer parameters
In my array of y's, I will search for element "x", when executing Array.BinarySearch<string>(yArray, x, m_stringComparer);
- In .net 3.5, for the exact same code, i get X=X and Y=Y
- In .net 4.0 I get: X=Y and Y=X

This completely broke the main word search game mechanic of a customer project that's i've been using for upgrade testing.

To repro this:
1. download this project
2. Open it with Unity 18.3 --> 19.2
3. Enter Play Mode and press SPACE
4. The project is submitted with .NET 3.5 and it will print : X=X and Y=Y
5. Change to .NET 4.0 and repeat
6. Notice it will now print: X=Y and Y=X

Reproduced with: 2017.4.3f1, 2018.3.9f1, 2019.1.0b8, 2019.2.0a10 (trunk) --> when switching to .NET 4.0
Cannot reproduce with all of the above if .NET is 3.5
In 2019.2, .NET 3.5 is not even an option anymore so the upgraded project just breaks without a workaround (besides changing the code)

  1. Response avatar

    Resolution Note (fix version ):

    The IComparer<T> implementation is relying on order of parameters being passed in. It needs to correctly compare parameters not matter the order.

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