using FluentAssertions;
using Microsoft.AspNetCore.Mvc.ModelBinding;

[Test]
public void Failed_On_FormatException_Inside_FluentAssertions_When_Strings_Are_Different()
{
    string propertyName = "APropertyName";
    string value = "A value";
    ModelStateDictionary modelState = new ModelStateDictionary();

    modelState.AddModelError(propertyName, $"The value '{value}' is invalid and more characters to be different than expected.");

    modelState.Should().HaveCount(1)
        .And.ContainSingle(kvp => kvp.Key == propertyName)
        .Which.Value.Errors.Should().HaveCount(1)
        .And.ContainSingle(modelError =>
            string.Equals(modelError.ErrorMessage, $"The value '{value}' is invalid."));
}

[Test]
public void Succeed_When_Strings_Are_Same()
{
    string propertyName = "APropertyName";
    string value = "A value";
    ModelStateDictionary modelState = new ModelStateDictionary();

    modelState.AddModelError(propertyName, $"The value '{value}' is invalid.");

    modelState.Should().HaveCount(1)
        .And.ContainSingle(kvp => kvp.Key == propertyName)
        .Which.Value.Errors.Should().HaveCount(1)
        .And.ContainSingle(modelError =>
            string.Equals(modelError.ErrorMessage, $"The value '{value}' is invalid."));
}