Generic method ShouldAll for FluentAssertions

This is a simple etension method for Fluent Assertions called ShouldAll that can be run on a collection and you can pass in your predicate of your choice and see the output. Consider this unit test:

         var oneyearPeriodComparions = new []
            {
                new ReferencePeriodComparisonResult { ReferencePeriod = reportPeriod2017 , CalculatedPeriod = calculatedReportPeriod2017.First() },
                new ReferencePeriodComparisonResult { ReferencePeriod = reportPeriod2017 , CalculatedPeriod = calculatedReportPeriod2017.Last()},
                new ReferencePeriodComparisonResult { ReferencePeriod = reportPeriod2018 , CalculatedPeriod = calculatedReportPeriod2018.First()},
                new ReferencePeriodComparisonResult { ReferencePeriod = reportPeriod2018 , CalculatedPeriod = calculatedReportPeriod2018.Last() },
                new ReferencePeriodComparisonResult { ReferencePeriod = reportPeriod2019 , CalculatedPeriod = calculatedReportPeriod2019.First() },
                new ReferencePeriodComparisonResult { ReferencePeriod = reportPeriod2019 , CalculatedPeriod = calculatedReportPeriod2019.Last() }
            };

            oneyearPeriodComparions.ShouldAll(comparison => comparison.CalculatedPeriod.ReportPeriodStartDateAndEndDateIsEqualTo(comparison.ReferencePeriod), outputPassingTests:true);

This uses this extension test for Fluent Assertions:

using FluentAssertions;
using System;
using System.Collections.Generic;
using System.Linq.Expressions;

namespace SomeAcme.SomeLib
{

    public static class FluentAssertionsExtensions
    {

        /// <summary>
        /// Inspects that all tests are passing for given collection and given predicate
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="instances"></param>
        /// <param name="predicate"></param>
        /// <param name="outputFailingTests"></param>
        public static void ShouldAll<T>(this IEnumerable<T> instances, Expression<Func<T, bool>> predicate, bool outputFailingTests = true, bool outputPassingTests = false)
        {
            foreach (var instance in instances)
            {
                var isTestPassing = predicate.Compile().Invoke(instance);
                if (!isTestPassing && outputFailingTests || outputPassingTests)
                    Console.WriteLine($@"Test Running against object: {instance} Test Pass?:{isTestPassing}");
                isTestPassing.Should().Be(true);
            }
        }
    }

}

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