PVS-Studio: fixed the potential vulnerability CWE-670 (Always-Incorrect Control Flow Implementation)

[IvanKishchenko]

We have found and fixed a vulnerability CWE-670 (Always-Incorrect Control Flow Implementation) using PVS-Studio tool.
Analyzer warnings: V3014, V3015 and V3081.
PVS-Studio is a static code analyzer for C, C++ and C#.

Fixes:

• When comparing two statements through ExpressionEqualityComparer, the method GetHashCode was returning incorrect result for the expressions of the MemberInit with a list of arguments.
  We have written a unit test that proves that (See ExpressionCompareByHashCodeTest)

• V3014 It is likely that a wrong variable is being incremented inside the 'for' operator. Consider reviewing 'i'. EFCore ExpressionEqualityComparer.cs 214
• V3015 It is likely that a wrong variable is being compared inside the 'for' operator. Consider reviewing 'i' EFCore ExpressionEqualityComparer.cs 214

• Also, we have corrected one of the unit tests, that was working incorrectly, to our mind.

• V3081 The 'j' counter is not used inside a nested loop. Consider inspecting usage of 'i' counter. EFCore.Specification.Tests ComplexNavigationsQueryTestBase.cs 2393

[dnfclas]

@IvanKishchenko,
Thanks for having already signed the Contribution License Agreement. Your agreement was validated by .NET Foundation. We will now review your pull request.
Thanks,
.NET Foundation Pull Request Bot

[dnfclas]

@IvanKishchenko,
Thanks for having already signed the Contribution License Agreement. Your agreement was validated by .NET Foundation. We will now review your pull request.
Thanks,
.NET Foundation Pull Request Bot

[smitpatel]

@IvanKishchenko - We wanted to test the functionality in terms of query pipeline and not just equality comparer to see functional impact of the error. Since the test was complicated to explain over forums, I added it myself. Though I have preserved your commit & it will be part of our code base.
Thank you for the contribution.