Fix S5034 FP: ValueTask.IsCompletedSuccessfully not considered in ternary operator

[fiotti]

Description

S5034 does not take ternary operators into consideration.

Repro steps

class Test
{
  static ValueTask<IEnumerable> MakeGeneric(ValueTask<IEnumerable<T>> task)
    => task.IsCompletedSuccessfully
      // S5034: Refactor this 'ValueTask' usage to consume the result only if the operation has completed successfully.
      ? ValueTask.FromResult<IEnumerable>(task.Result)
      : MakeGenericSlow(task);

  static async ValueTask<IEnumerable> MakeGenericSlow(ValueTask<IEnumerable<T>> task)
    => await task;
}

Expected behavior

No warning.

Actual behavior

S5034: Refactor this 'ValueTask' usage to consume the result only if the operation has completed successfully.

Known workarounds

class Test
{
  static ValueTask<IEnumerable> MakeGeneric(ValueTask<IEnumerable<T>> task)
  {
    if (task.IsCompletedSuccessfully)
      return ValueTask.FromResult<IEnumerable>(task.Result); // No warning.
      
    return MakeGenericSlow(task);
  }

  static async ValueTask<IEnumerable> MakeGenericSlow(ValueTask<IEnumerable<T>> task)
    => await task;
}

Related information

• SonarLint for Visual Studio 2022, version 8.9.0.92083
• Visual Studio Professional 2022 (64 bit), version 17.10.4
• dotnet 8.0.303
• MSBuild version 17.10.4+10fbfbf2e for .NET Framework, version 17.10.4.21802
• Windows 11 Pro 23H2 22631.3880

[mary-georgiou-sonarsource]

Hello @fiotti I confirm this is a false positive.
Thank you for reporting this.