OpenXmlIncrementalSourceGeneratorVerifier.cs

// Copyright (c) Microsoft. All rights reserved.
// Licensed under the MIT license. See LICENSE file in the project root for full license information.

using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.CSharp;
using Microsoft.CodeAnalysis.CSharp.Testing;
using Microsoft.CodeAnalysis.Testing;
using System;
using System.Collections.Generic;
using System.Collections.Immutable;

namespace DocumentFormat.OpenXml.Generator.Tests.Verifiers
{
    public static partial class OpenXmlIncrementalSourceGeneratorVerifier<TSourceGenerator>
        where TSourceGenerator : IIncrementalGenerator, new()
    {
        public class Test : CSharpSourceGeneratorTest<EmptySourceGeneratorProvider, DefaultVerifier>
        {
            private static ImmutableDictionary<string, ReportDiagnostic> NullableWarnings { get; } = GetNullableWarningsFromCompiler();

            public Test()
            {
            }

            public LanguageVersion LanguageVersion { get; set; } = LanguageVersion.Default;

            protected override IEnumerable<Type> GetSourceGenerators() => new[] { typeof(TSourceGenerator) };

            protected override CompilationOptions CreateCompilationOptions()
            {
                var compilationOptions = base.CreateCompilationOptions();
                return compilationOptions.WithSpecificDiagnosticOptions(
                    compilationOptions.SpecificDiagnosticOptions.SetItems(NullableWarnings));
            }

            protected override ParseOptions CreateParseOptions()
            {
                return ((CSharpParseOptions)base.CreateParseOptions()).WithLanguageVersion(LanguageVersion);
            }

            private static ImmutableDictionary<string, ReportDiagnostic> GetNullableWarningsFromCompiler()
            {
                string[] args = { "/warnaserror:nullable" };
                var commandLineArguments = CSharpCommandLineParser.Default.Parse(args, baseDirectory: Environment.CurrentDirectory, sdkDirectory: Environment.CurrentDirectory);
                return commandLineArguments.CompilationOptions.SpecificDiagnosticOptions;
            }
        }
    }
}