feat: add null-safe TryFromValue signature and tests

[teesofttech]

feat: add null-safe TryFromValue signature and tests

[Copilot]

Pull request overview

This PR updates the SmartEnum<TEnum, TValue>.TryFromValue API to be null-safe and adds unit tests covering TryFromValue behavior for both int-backed and string-backed smart enums.

Changes:

• Update TryFromValue to accept nullable input (TValue?) and avoid exceptions on null input.
• Add new unit tests validating TryFromValue success/failure cases for value and string enums.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
src/SmartEnum/SmartEnum.cs	Adjusts TryFromValue signature/implementation to handle nullable inputs.
test/SmartEnum.UnitTests/SmartEnumTryFromValue.cs	Adds tests exercising TryFromValue behavior for matching/non-matching values and null string input.

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[teesofttech]

@ardalis Can you review this PR please

[ardalis]

Looks like it doesn't work with netstandard and has some other things needed to change based on the broken build:

Warning: /home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.SystemTextJson.UnitTests/SmartEnumNameConverterTests.cs(112,9): warning S125: Remove this commented out code. (https://rules.sonarsource.com/csharp/RSPEC-125) [/home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.SystemTextJson.UnitTests/SmartEnum.SystemTextJson.UnitTests.csproj::TargetFramework=net8.0]
Warning: /home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.SystemTextJson.UnitTests/SmartEnumValueConverterTests.cs(133,9): warning S125: Remove this commented out code. (https://rules.sonarsource.com/csharp/RSPEC-125) [/home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.SystemTextJson.UnitTests/SmartEnum.SystemTextJson.UnitTests.csproj::TargetFramework=net8.0]
Warning: /home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.SystemTextJson.UnitTests/TestEnums.cs(68,32): warning S3887: Use an immutable collection or reduce the accessibility of the non-private readonly field 'Instance'. (https://rules.sonarsource.com/csharp/RSPEC-3887) [/home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.SystemTextJson.UnitTests/SmartEnum.SystemTextJson.UnitTests.csproj::TargetFramework=net8.0]
Warning: /home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.SystemTextJson.UnitTests/TestEnums.cs(74,32): warning S3887: Use an immutable collection or reduce the accessibility of the non-private readonly field 'Instance'. (https://rules.sonarsource.com/csharp/RSPEC-3887) [/home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.SystemTextJson.UnitTests/SmartEnum.SystemTextJson.UnitTests.csproj::TargetFramework=net8.0]
Warning: /usr/share/dotnet/sdk/10.0.301/Sdks/Microsoft.NET.Sdk/targets/Microsoft.NET.Sdk.targets(308,5): warning NETSDK1206: Found version-specific or distribution-specific runtime identifier(s): alpine-arm, alpine-arm64, alpine-x64. Affected libraries: SQLitePCLRaw.lib.e_sqlite3. In .NET 8.0 and higher, assets for version-specific and distribution-specific runtime identifiers will not be found by default. See https://aka.ms/dotnet/rid-usage for details. [/home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.EFCore.IntegrationTests/SmartEnum.EFCore.IntegrationTests.csproj::TargetFramework=net8.0]
Error: /home/runner/work/SmartEnum/SmartEnum/src/SmartEnum/SmartEnum.cs(274,57): error CS0246: The type or namespace name 'NotNullWhenAttribute' could not be found (are you missing a using directive or an assembly reference?) [/home/runner/work/SmartEnum/SmartEnum/src/SmartEnum/SmartEnum.csproj::TargetFramework=netstandard2.0]
Error: /home/runner/work/SmartEnum/SmartEnum/src/SmartEnum/SmartEnum.cs(274,57): error CS0246: The type or namespace name 'NotNullWhen' could not be found (are you missing a using directive or an assembly reference?) [/home/runner/work/SmartEnum/SmartEnum/src/SmartEnum/SmartEnum.csproj::TargetFramework=netstandard2.0]
222 Warning(s)
2 Error(s)

[teesofttech]

Looks like it doesn't work with netstandard and has some other things needed to change based on the broken build:

Warning: /home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.SystemTextJson.UnitTests/SmartEnumNameConverterTests.cs(112,9): warning S125: Remove this commented out code. (https://rules.sonarsource.com/csharp/RSPEC-125) [/home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.SystemTextJson.UnitTests/SmartEnum.SystemTextJson.UnitTests.csproj::TargetFramework=net8.0] Warning: /home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.SystemTextJson.UnitTests/SmartEnumValueConverterTests.cs(133,9): warning S125: Remove this commented out code. (https://rules.sonarsource.com/csharp/RSPEC-125) [/home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.SystemTextJson.UnitTests/SmartEnum.SystemTextJson.UnitTests.csproj::TargetFramework=net8.0] Warning: /home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.SystemTextJson.UnitTests/TestEnums.cs(68,32): warning S3887: Use an immutable collection or reduce the accessibility of the non-private readonly field 'Instance'. (https://rules.sonarsource.com/csharp/RSPEC-3887) [/home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.SystemTextJson.UnitTests/SmartEnum.SystemTextJson.UnitTests.csproj::TargetFramework=net8.0] Warning: /home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.SystemTextJson.UnitTests/TestEnums.cs(74,32): warning S3887: Use an immutable collection or reduce the accessibility of the non-private readonly field 'Instance'. (https://rules.sonarsource.com/csharp/RSPEC-3887) [/home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.SystemTextJson.UnitTests/SmartEnum.SystemTextJson.UnitTests.csproj::TargetFramework=net8.0] Warning: /usr/share/dotnet/sdk/10.0.301/Sdks/Microsoft.NET.Sdk/targets/Microsoft.NET.Sdk.targets(308,5): warning NETSDK1206: Found version-specific or distribution-specific runtime identifier(s): alpine-arm, alpine-arm64, alpine-x64. Affected libraries: SQLitePCLRaw.lib.e_sqlite3. In .NET 8.0 and higher, assets for version-specific and distribution-specific runtime identifiers will not be found by default. See https://aka.ms/dotnet/rid-usage for details. [/home/runner/work/SmartEnum/SmartEnum/test/SmartEnum.EFCore.IntegrationTests/SmartEnum.EFCore.IntegrationTests.csproj::TargetFramework=net8.0] Error: /home/runner/work/SmartEnum/SmartEnum/src/SmartEnum/SmartEnum.cs(274,57): error CS0246: The type or namespace name 'NotNullWhenAttribute' could not be found (are you missing a using directive or an assembly reference?) [/home/runner/work/SmartEnum/SmartEnum/src/SmartEnum/SmartEnum.csproj::TargetFramework=netstandard2.0] Error: /home/runner/work/SmartEnum/SmartEnum/src/SmartEnum/SmartEnum.cs(274,57): error CS0246: The type or namespace name 'NotNullWhen' could not be found (are you missing a using directive or an assembly reference?) [/home/runner/work/SmartEnum/SmartEnum/src/SmartEnum/SmartEnum.csproj::TargetFramework=netstandard2.0] 222 Warning(s) 2 Error(s)

Looking into this now

[teesofttech]

Fixed now

@ardalis