CliFx/CliFx.Tests/HelpTextSpecs.cs

using System;
using System.Collections.Generic;
using System.Threading.Tasks;
using CliFx.Tests.Utils;
using CliFx.Tests.Utils.Extensions;
using FluentAssertions;
using Xunit;
using Xunit.Abstractions;

namespace CliFx.Tests;

public class HelpTextSpecs : SpecsBase
{
    public HelpTextSpecs(ITestOutputHelper testOutput)
        : base(testOutput)
    {
    }

    [Fact]
    public async Task Help_text_is_printed_if_no_arguments_are_provided_and_the_default_command_is_not_defined()
    {
        // Arrange
        var application = new CliApplicationBuilder()
            .UseConsole(FakeConsole)
            .SetDescription("This will be in help text")
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            Array.Empty<string>(),
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().Contain("This will be in help text");
    }

    [Fact]
    public async Task Help_text_is_printed_if_provided_arguments_contain_the_help_option()
    {
        // Arrange
        var commandType = DynamicCommandBuilder.Compile(
            // language=cs
            @"
[Command]
public class DefaultCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommand(commandType)
            .UseConsole(FakeConsole)
            .SetDescription("This will be in help text")
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().Contain("This will be in help text");
    }

    [Fact]
    public async Task Help_text_is_printed_if_provided_arguments_contain_the_help_option_even_if_the_default_command_is_not_defined()
    {
        // Arrange
        var commandTypes = DynamicCommandBuilder.CompileMany(
            // language=cs
            @"
[Command(""cmd"")]
public class NamedCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}

[Command(""cmd child"")]
public class NamedChildCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommands(commandTypes)
            .UseConsole(FakeConsole)
            .SetDescription("This will be in help text")
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().Contain("This will be in help text");
    }

    [Fact]
    public async Task Help_text_for_a_specific_named_command_is_printed_if_provided_arguments_match_its_name_and_contain_the_help_option()
    {
        // Arrange
        var commandTypes = DynamicCommandBuilder.CompileMany(
            // language=cs
            @"
[Command]
public class DefaultCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}

[Command(""cmd"", Description = ""Description of a named command."")]
public class NamedCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}

[Command(""cmd child"")]
public class NamedChildCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommands(commandTypes)
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"cmd", "--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().Contain("Description of a named command.");
    }

    [Fact]
    public async Task Help_text_for_a_specific_named_child_command_is_printed_if_provided_arguments_match_its_name_and_contain_the_help_option()
    {
        // Arrange
        var commandTypes = DynamicCommandBuilder.CompileMany(
            // language=cs
            @"
[Command]
public class DefaultCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}

[Command(""cmd"")]
public class NamedCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}

[Command(""cmd child"", Description = ""Description of a named child command."")]
public class NamedChildCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommands(commandTypes)
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"cmd", "sub", "--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().Contain("Description of a named child command.");
    }

    [Fact]
    public async Task Help_text_is_printed_on_invalid_user_input()
    {
        // Arrange
        var application = new CliApplicationBuilder()
            .AddCommand<NoOpCommand>()
            .UseConsole(FakeConsole)
            .SetDescription("This will be in help text")
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"invalid-command", "--invalid-option"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();
        var stdErr = FakeConsole.ReadErrorString();

        // Assert
        exitCode.Should().NotBe(0);
        stdOut.Should().Contain("This will be in help text");
        stdErr.Should().NotBeNullOrWhiteSpace();
    }

    [Fact]
    public async Task Help_text_shows_application_metadata()
    {
        // Arrange
        var application = new CliApplicationBuilder()
            .UseConsole(FakeConsole)
            .SetTitle("App title")
            .SetDescription("App description")
            .SetVersion("App version")
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().ContainAll(
            "App title",
            "App description",
            "App version"
        );
    }

    [Fact]
    public async Task Help_text_shows_command_description()
    {
        // Arrange
        var commandType = DynamicCommandBuilder.Compile(
            // language=cs
            @"
[Command(Description = ""Description of the default command."")]
public class DefaultCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommand(commandType)
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().ContainAllInOrder(
            "DESCRIPTION",
            "Description of the default command."
        );
    }

    [Fact]
    public async Task Help_text_shows_usage_format_which_indicates_how_to_execute_a_named_command()
    {
        // Arrange
        var commandTypes = DynamicCommandBuilder.CompileMany(
            // language=cs
            @"
[Command]
public class DefaultCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}

[Command(""cmd"")]
public class NamedCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommands(commandTypes)
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().ContainAllInOrder(
            "USAGE",
            "[command]", "[...]"
        );
    }

    [Fact]
    public async Task Help_text_shows_usage_format_which_lists_all_parameters()
    {
        // Arrange
        var commandType = DynamicCommandBuilder.Compile(
            // language=cs
            @"
[Command]
public class Command : ICommand
{
    [CommandParameter(0)]
    public string Foo { get; set; }
    
    [CommandParameter(1)]
    public string Bar { get; set; }
    
    [CommandParameter(2)]
    public IReadOnlyList<string> Baz { get; set; }
    
    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommand(commandType)
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().ContainAllInOrder(
            "USAGE",
            "<foo>", "<bar>", "<baz...>"
        );
    }

    [Fact]
    public async Task Help_text_shows_usage_format_which_lists_all_required_options()
    {
        // Arrange
        var commandType = DynamicCommandBuilder.Compile(
            // language=cs
            @"
[Command]
public class Command : ICommand
{
    [CommandOption(""foo"", IsRequired = true)]
    public string Foo { get; set; }
    
    [CommandOption(""bar"")]
    public string Bar { get; set; }
    
    [CommandOption(""baz"", IsRequired = true)]
    public IReadOnlyList<string> Baz { get; set; }
    
    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommand(commandType)
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().ContainAllInOrder(
            "USAGE",
            "--foo <value>", "--baz <values...>", "[options]"
        );
    }

    [Fact]
    public async Task Help_text_shows_all_parameters_and_options()
    {
        // Arrange
        var commandType = DynamicCommandBuilder.Compile(
            // language=cs
            @"
[Command]
public class Command : ICommand
{
    [CommandParameter(0, Name = ""foo"", Description = ""Description of foo."")]
    public string Foo { get; set; }
    
    [CommandOption(""bar"", Description = ""Description of bar."")]
    public string Bar { get; set; }
    
    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommand(commandType)
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().ContainAllInOrder(
            "PARAMETERS",
            "foo", "Description of foo.",
            "OPTIONS",
            "--bar", "Description of bar."
        );
    }

    [Fact]
    public async Task Help_text_shows_the_implicit_help_and_version_options_on_the_default_command()
    {
        // Arrange
        var commandType = DynamicCommandBuilder.Compile(
            // language=cs
            @"
[Command]
public class Command : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommand(commandType)
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().ContainAllInOrder(
            "OPTIONS",
            "-h", "--help", "Shows help text",
            "--version", "Shows version information"
        );
    }

    [Fact]
    public async Task Help_text_shows_the_implicit_help_option_but_not_the_version_option_on_a_named_command()
    {
        // Arrange
        var commandType = DynamicCommandBuilder.Compile(
            // language=cs
            @"
[Command(""cmd"")]
public class Command : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommand(commandType)
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"cmd", "--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().ContainAllInOrder(
            "OPTIONS",
            "-h", "--help", "Shows help text"
        );
        stdOut.Should().NotContainAny(
            "--version", "Shows version information"
        );
    }

    [Fact]
    public async Task Help_text_shows_all_valid_values_for_enum_parameters_and_options()
    {
        // Arrange
        var commandType = DynamicCommandBuilder.Compile(
            // language=cs
            @"
public enum CustomEnum { One, Two, Three }

[Command]
public class Command : ICommand
{
    [CommandParameter(0)]
    public CustomEnum Foo { get; set; }
    
    [CommandOption(""bar"")]
    public CustomEnum Bar { get; set; }
    
    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommand(commandType)
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().ContainAllInOrder(
            "PARAMETERS",
            "foo", "Choices:", "One", "Two", "Three",
            "OPTIONS",
            "--bar", "Choices:", "One", "Two", "Three"
        );
    }

    [Fact]
    public async Task Help_text_shows_all_valid_values_for_non_scalar_enum_parameters_and_options()
    {
        // Arrange
        var commandType = DynamicCommandBuilder.Compile(
            // language=cs
            @"
public enum CustomEnum { One, Two, Three }

[Command]
public class Command : ICommand
{
    [CommandParameter(0)]
    public IReadOnlyList<CustomEnum> Foo { get; set; }

    [CommandOption(""bar"")]
    public IReadOnlyList<CustomEnum> Bar { get; set; }

    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommand(commandType)
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().ContainAllInOrder(
            "PARAMETERS",
            "foo", "Choices:", "One", "Two", "Three",
            "OPTIONS",
            "--bar", "Choices:", "One", "Two", "Three"
        );
    }

    [Fact]
    public async Task Help_text_shows_all_valid_values_for_nullable_enum_parameters_and_options()
    {
        // Arrange
        var commandType = DynamicCommandBuilder.Compile(
            // language=cs
            @"
public enum CustomEnum { One, Two, Three }

[Command]
public class Command : ICommand
{
    [CommandParameter(0)]
    public CustomEnum? Foo { get; set; }

    [CommandOption(""bar"")]
    public IReadOnlyList<CustomEnum?> Bar { get; set; }

    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommand(commandType)
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().ContainAllInOrder(
            "PARAMETERS",
            "foo", "Choices:", "One", "Two", "Three",
            "OPTIONS",
            "--bar", "Choices:", "One", "Two", "Three"
        );
    }

    [Fact]
    public async Task Help_text_shows_environment_variables_for_options_that_have_them_configured_as_fallback()
    {
        // Arrange
        var commandType = DynamicCommandBuilder.Compile(
            // language=cs
            @"
public enum CustomEnum { One, Two, Three }

[Command]
public class Command : ICommand
{
    [CommandOption(""foo"", EnvironmentVariable = ""ENV_FOO"")]
    public CustomEnum Foo { get; set; }
    
    [CommandOption(""bar"", EnvironmentVariable = ""ENV_BAR"")]
    public CustomEnum Bar { get; set; }
    
    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommand(commandType)
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().ContainAllInOrder(
            "OPTIONS",
            "--foo", "Environment variable:", "ENV_FOO",
            "--bar", "Environment variable:", "ENV_BAR"
        );
    }

    [Fact]
    public async Task Help_text_shows_default_values_for_non_required_options()
    {
        // Arrange
        var commandType = DynamicCommandBuilder.Compile(
            // language=cs
            @"
public enum CustomEnum { One, Two, Three }

[Command]
public class Command : ICommand
{
    [CommandOption(""foo"")]
    public object Foo { get; set; } = 42;

    [CommandOption(""bar"")]
    public string Bar { get; set; } = ""hello"";

    [CommandOption(""baz"")]
    public IReadOnlyList<string> Baz { get; set; } = new[] {""one"", ""two"", ""three""};

    [CommandOption(""qwe"")]
    public bool Qwe { get; set; } = true;

    [CommandOption(""qop"")]
    public int? Qop { get; set; } = 1337;

    [CommandOption(""zor"")]
    public TimeSpan Zor { get; set; } = TimeSpan.FromMinutes(123);

    [CommandOption(""lol"")]
    public CustomEnum Lol { get; set; } = CustomEnum.Two;
    
    [CommandOption(""hmm"", IsRequired = true)]
    public string Hmm { get; set; } = ""not printed"";
    
    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommand(commandType)
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().ContainAllInOrder(
            "OPTIONS",
            "--foo", "Default:", "42",
            "--bar", "Default:", "hello",
            "--baz", "Default:", "one", "two", "three",
            "--qwe", "Default:", "True",
            "--qop", "Default:", "1337",
            "--zor", "Default:", "02:03:00",
            "--lol", "Default:", "Two"
        );
        stdOut.Should().NotContain("not printed");
    }

    [Fact]
    public async Task Help_text_shows_all_immediate_child_commands()
    {
        // Arrange
        var commandTypes = DynamicCommandBuilder.CompileMany(
            // language=cs
            @"
[Command(""cmd1"", Description = ""Description of one command."")]
public class FirstCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}

[Command(""cmd2"", Description = ""Description of another command."")]
public class SecondCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}

[Command(""cmd2 child"", Description = ""Description of another command's child command."")]
public class SecondCommandChildCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommands(commandTypes)
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().ContainAllInOrder(
            "COMMANDS",
            "cmd1", "Description of one command.",
            "cmd2", "Description of another command."
        );

        // `cmd2 child` will still appear in the list of `cmd2` subcommands,
        // but its description will not be seen.
        stdOut.Should().NotContain(
            "Description of another command's child command."
        );
    }

    [Fact]
    public async Task Help_text_shows_all_immediate_child_commands_of_each_child_command()
    {
        // Arrange
        var commandTypes = DynamicCommandBuilder.CompileMany(
            // language=cs
            @"
[Command(""cmd1"")]
public class FirstCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}

[Command(""cmd1 child1"")]
public class FirstCommandFirstChildCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}

[Command(""cmd2"")]
public class SecondCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}

[Command(""cmd2 child11"")]
public class SecondCommandFirstChildCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}

[Command(""cmd2 child2"")]
public class SecondCommandSecondChildCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommands(commandTypes)
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().ContainAllInOrder(
            "COMMANDS",
            "cmd1", "Subcommands:", "cmd1 child1",
            "cmd2", "Subcommands:", "cmd2 child1", "cmd2 child2"
        );
    }

    [Fact]
    public async Task Help_text_shows_non_immediate_child_commands_if_they_do_not_have_a_more_specific_parent()
    {
        // Arrange
        var commandTypes = DynamicCommandBuilder.CompileMany(
            // language=cs
            @"
[Command(""cmd1"")]
public class FirstCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}

[Command(""cmd2 child1"")]
public class SecondCommandFirstChildCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}

[Command(""cmd2 child2"")]
public class SecondCommandSecondChildCommand : ICommand
{
    public ValueTask ExecuteAsync(IConsole console) => default;
}
");

        var application = new CliApplicationBuilder()
            .AddCommands(commandTypes)
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--help"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Should().ContainAllInOrder(
            "COMMANDS",
            "cmd1",
            "cmd2 child1",
            "cmd2 child2"
        );
    }

    [Fact]
    public async Task Version_text_is_printed_if_provided_arguments_contain_the_version_option()
    {
        // Arrange
        var application = new CliApplicationBuilder()
            .AddCommand<NoOpCommand>()
            .SetVersion("v6.9")
            .UseConsole(FakeConsole)
            .Build();

        // Act
        var exitCode = await application.RunAsync(
            new[] {"--version"},
            new Dictionary<string, string>()
        );

        var stdOut = FakeConsole.ReadOutputString();

        // Assert
        exitCode.Should().Be(0);
        stdOut.Trim().Should().Be("v6.9");
    }
}