/src/CommandLine.Tests/Unit/Core/InstanceChooserTests.cs

// Copyright 2005-2013 Giacomo Stelluti Scala & Contributors. All rights reserved. See doc/License.md in the project root for license information.



using System;

using System.Globalization;

using System.Linq;

using CommandLine.Core;

using CommandLine.Tests.Fakes;

using FluentAssertions;

using Xunit;



namespace CommandLine.Tests.Unit.Core

{

    public class InstanceChooserTests

    {        

        [Fact]

        public void Parse_empty_array_returns_NullInstance()

        {

            // Fixture setup

            var expectedErrors = new[] { new NoVerbSelectedError() };



            // Exercize system 

            var result = InstanceChooser.Choose(

                new[] { typeof(AddOptions), typeof(CommitOptions), typeof(CloneOptions) },

                new string[] { },

                StringComparer.Ordinal,

                CultureInfo.InvariantCulture);



            // Verify outcome

            Assert.IsType<NullInstance>(result.Value);

            Assert.True(expectedErrors.SequenceEqual(result.Errors));

            // Teardown

        }



        [Fact]

        public void Explicit_help_request_generates_HelpVerbRequestedError()

        {

            // Fixture setup

            var expectedErrors = new[] { new HelpVerbRequestedError(null, null, false) };



            // Exercize system 

            var result = InstanceChooser.Choose(

                new[] { typeof(AddOptions), typeof(CommitOptions), typeof(CloneOptions) },

                new[] { "help" },

                StringComparer.Ordinal,

                CultureInfo.InvariantCulture);



            // Verify outcome

            Assert.IsType<NullInstance>(result.Value);

            Assert.True(expectedErrors.SequenceEqual(result.Errors));

            // Teardown

        }



        [Fact]

        public void Explicit_help_request_for_a_valid_verb_generates_HelpVerbRequestedError_with_appropriate_data()

        {

            // Fixture setup

            var expectedErrors = new[] { new HelpVerbRequestedError("commit", typeof(CommitOptions), true) };



            // Exercize system 

            var result = InstanceChooser.Choose(

                new[] { typeof(AddOptions), typeof(CommitOptions), typeof(CloneOptions) },

                new[] { "help", "commit" },

                StringComparer.Ordinal,

                CultureInfo.InvariantCulture);



            // Verify outcome

            Assert.IsType<NullInstance>(result.Value);

            Assert.True(expectedErrors.SequenceEqual(result.Errors));

            // Teardown

        }



        [Fact]

        public void Explicit_help_request_for_an_invalid_verb_generates_HelpVerbRequestedError_with_Matched_set_to_false()

        {

            // Fixture setup

            var expectedErrors = new[] { new HelpVerbRequestedError(null, null, false) };



            // Exercize system 

            var result = InstanceChooser.Choose(

                new[] { typeof(AddOptions), typeof(CommitOptions), typeof(CloneOptions) },

                new[] { "help", "earthunderalienattack" },

                StringComparer.Ordinal,

                CultureInfo.InvariantCulture);



            // Verify outcome

            Assert.IsType<NullInstance>(result.Value);

            Assert.True(expectedErrors.SequenceEqual(result.Errors));

            // Teardown

        }



        [Fact]

        public void Parse_existing_verb_returns_verb_instance()

        {

            // Fixture setup

            var expected = new AddOptions { Patch = true, FileName = "dummy.bin"};



            // Exercize system 

            var result = InstanceChooser.Choose(

                new[] { typeof(AddOptions), typeof(CommitOptions), typeof(CloneOptions) },

                new[] { "add", "--patch", "dummy.bin" },

                StringComparer.Ordinal,

                CultureInfo.InvariantCulture);



            // Verify outcome

            Assert.IsType<AddOptions>(result.Value);

            expected.ShouldHave().AllRuntimeProperties().EqualTo(result.Value);

            // Teardown

        }    

    }

}