CliFx/CliFx.Tests/Utils/Extensions/AssertionExtensions.cs

using System;
using System.Collections.Generic;
using FluentAssertions;
using FluentAssertions.Execution;
using FluentAssertions.Primitives;

namespace CliFx.Tests.Utils.Extensions;

internal static class AssertionExtensions
{
    public static void ConsistOfLines(
        this StringAssertions assertions,
        IEnumerable<string> lines)
    {
        var actualLines = assertions.Subject.Split(new[] {'\n', '\r'}, StringSplitOptions.RemoveEmptyEntries);
        actualLines.Should().Equal(lines);
    }

    public static void ConsistOfLines(
        this StringAssertions assertions,
        params string[] lines) =>
        assertions.ConsistOfLines((IEnumerable<string>) lines);

    public static AndConstraint<StringAssertions> ContainAllInOrder(
        this StringAssertions assertions,
        IEnumerable<string> values)
    {
        var lastIndex = 0;

        foreach (var value in values)
        {
            var index = assertions.Subject.IndexOf(value, lastIndex, StringComparison.Ordinal);

            if (index < 0)
            {
                Execute.Assertion.FailWith(
                    $"Expected string '{assertions.Subject}' to contain '{value}' after position {lastIndex}."
                );
            }

            lastIndex = index;
        }

        return new(assertions);
    }

    public static AndConstraint<StringAssertions> ContainAllInOrder(
        this StringAssertions assertions,
        params string[] values) =>
        assertions.ContainAllInOrder((IEnumerable<string>) values);
}