TDDで作るRoslynアナライザー【DeNA TechCon 2023】

youtube：https://youtu.be/ETWHB2yMdxg

概要：
.NETの静的解析器であるRoslynアナライザーを使うことで、ビルドすることなく問題のあるコードを検出できます。
便利なRoslynアナライザーですが、 アナライザーのテストで苦労された人もいるのではないでしょうか？
DeNAが公開しているRoslynアナライザーのためのテスティングライブラリであるDena.CodeAnalysis.Testingを使うことで、アナライザーのユニットテストを簡単に導入できます。

このセッションではDena.CodeAnalysis.Testingを用いてRoslynアナライザーをTDDで作成する方法について紹介します。

登壇内でのリンク集：
p9, https://speakerdeck.com/dena_tech/unitykai-fa-defalsemisuwowei-ran-nifang-guroslynanaraizafalsesu-me-dena-techcon-2022
p53, https://github.com/DeNA/RoslynAnalyzerTemplate
p54-1, https://github.com/DeNA/BanAsyncTaskAnalyzer
p54-2, https://github.com/DeNA/BanAsyncTaskAnalyzer/commit/0b2af3934a3a3759fbe25e73e527d4777b8a9d3b
p58, https://github.com/Cysharp/UniTask

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https://youtube.com/c/denatech?sub_confirmation=1

◆ Twitter
https://twitter.com/DeNAxTech

◆ DeNA Engineering
https://engineering.dena.com/

◆ DeNA Engineer Blog
https://engineering.dena.com/blog/

◆ DeNA TechCon 2023 公式サイト
https://techcon2023.dena.dev/

Transcript

1. TDDで作るRoslynアナライザー
   品質本部品質管理部SWET第二グループ
   Kazuma Inagaki
   1
   

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2. Kazuma Inagaki
   品質本部品質管理部SWET第二グループ
   @get_me_power

   令和にVimで就活した2021年新卒

   

   ゲーム領域における静的解析器の作成

   

   

   @get-me-power

   ※ TWITTER, TWEET, RETWEET and the Twitter Bird logo are trademarks of Twitter Inc. or its affiliates.
   2
   

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3. この発表で伝えたいこと
   3
   

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4. Dena.CodeAnalysis.Testingで
   Roslynアナライザーの
   ユニットテストを簡単にしよう
   4
   

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5. Dena.CodeAnalysis.Testingで
   Roslynアナライザーの
   ユニットテストを簡単にしよう
   5
   

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6. Roslynとは
   公開されているもの
   ■ C#、VB向けコンパイラ
   ■ コード生成API
   ■ コード解析API
   C#6.0から導入された.NETコンパイラプラットフォームの通称
   6
   

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7. Roslynとは
   公開されているもの
   ■ C#、VB向けコンパイラ
   ■ コード生成API
   ■ コード解析API
   C#6.0から導入された.NETコンパイラプラットフォームの通称
   7
   

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8. Roslynとは
   公開されているもの
   ■ C#、VB向けコンパイラ
   ■ コード生成API
   ■ コード解析API
   コードの問題を検出するプログラム
   Roslynアナライザー
   C#6.0から導入された.NETコンパイラプラットフォームの通称
   8
   

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9. https://speakerdeck.com/dena_tech/unitykai-fa-defalsemisuwowei-ran-nifang-guroslynanaraizafalsesu-me-dena-techcon-2022
   9
   

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10. Dena.CodeAnalysis.Testingで
    Roslynアナライザーの
    ユニットテストを簡単にしよう
    10
    

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11. ユニットテストの必要性
    11
    

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12. ユニットテストの必要性
    早期に欠陥を検知できる
    デグレーションを検知できる
    12
    

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13. Roslynアナライザーを作る上でも
    ユニットテストは有効
    13
    

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14. Roslynアナライザーのユニットテストに必要なもの
    ● 検査対象ソースコード
    ● アナライザーが出力する警告の期待結果
    ● アナライザーが実際に出力した値
    14
    

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15. Roslynアナライザーのユニットテストに必要なもの
    ● 検査対象ソースコード
    ● アナライザーが出力する警告の期待結果
    ● アナライザーが実際に出力した値
    15
    

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16. Roslynアナライザーのユニットテストは難しい
    16
    

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17. Roslynアナライザーのユニットテストは難しい
    既存のテスティングライブラリにデメリットがある
    17
    

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18. 既存のテスティングライブラリにデメリットがある
    Roslynアナライザーのユニットテストは難しい
    18
    

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19. 既存のテスティングライブラリのデメリット
    ● アナライザーの実行とアサーションが一体化している
    ● 引数が必要なアナライザーをインスタンス化するのが難しい
    ● 検査対象のソースコードのうちどこが問題なのか分かりにくい
    ● CodeFixProviderを指定する必要があった
    ●
    19
    

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20. 解決法
    20
    

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21. 解決法
    Dena.CodeAnalysis.Testingを使おう！
    21
    

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22. Dena.CodeAnalysis.Testingで
    Roslynアナライザーのユニットテストを簡単
    にしよう
    22
    

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23. Dena.CodeAnalysis.Testingができること
    ●
    23
    

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24. Dena.CodeAnalysis.Testingができること
    ● アナライザーの実行とアサーションを分離させる
    ● 引数が必要なアナライザーを指定する
    ● 検査対象ソースコードから得られる情報を増やす
    24
    

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25. Dena.CodeAnalysis.Testingができること
    ● アナライザーの実行とアサーションを分離させる
    ● 引数が必要なアナライザーを指定する
    ● 検査対象ソースコードから得られる情報を増やす
    25
    

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26. using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task EmptySourceCode_NoDiagnosticReport()
    {
    var source = "";
    await Verify.VerifyAnalyzerAsync(source);
    }
    標準ライブラリを使った
    テストコード
    26
    

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27. using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task EmptySourceCode_NoDiagnosticReport()
    {
    var source = "";
    await Verify.VerifyAnalyzerAsync(source);
    }
    アナライザー実行と
    アサーションが一体化している
    27
    

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28. using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task EmptySourceCode_NoDiagnosticReport()
    {
    var source = "";
    await Verify.VerifyAnalyzerAsync(source);
    }
    独自の比較ができない アナライザー実行とアサーションの間
    に処理を挟めない
    アナライザー実行と
    アサーションが一体化している
    28
    

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29. using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task EmptySourceCode_NoDiagnosticReport()
    {
    var source = "";
    await Verify.VerifyAnalyzerAsync(source);
    }
    public async Task EmptySourceCode_NoDiagnosticReport()
    {
    var source = "";
    var analyzer = new YourAnalyzer();
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    Assert.That(diagnostics.Length, Is.EqualTo(0));
    }
    Dena.CodeAnalysis.Testing使用
    29
    

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30. using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task EmptySourceCode_NoDiagnosticReport()
    {
    var source = "";
    await Verify.VerifyAnalyzerAsync(source);
    }
    public async Task EmptySourceCode_NoDiagnosticReport()
    {
    var source = "";
    var analyzer = new YourAnalyzer();
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    Assert.That(diagnostics.Length, Is.EqualTo(0));
    }
    Dena.CodeAnalysis.Testing使用
    アナライザー実行とアサーションを
    分離できる！
    30
    

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31. using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task EmptySourceCode_NoDiagnosticReport()
    {
    var source = "";
    await Verify.VerifyAnalyzerAsync(source);
    }
    public async Task EmptySourceCode_NoDiagnosticReport()
    {
    var source = "";
    var analyzer = new YourAnalyzer();
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    Assert.That(diagnostics.Length, Is.EqualTo(0));
    }
    Dena.CodeAnalysis.Testing使用
    アナライザー実行とアサーションを
    分離できる！
    31
    

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32. Dena.CodeAnalysis.Testingができること
    ● アナライザーの実行とアサーションを分離させる
    ● 引数が必要なアナライザーを指定する
    ● 検査対象ソースコードから得られる情報を増やす
    32
    

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33. using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task Foo()
    {
    var source = "";
    await Verify.VerifyAnalyzerAsync(source);
    }
    標準ライブラリを使った
    テストコード
    33
    

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34. using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task Foo()
    {
    var source = "";
    await Verify.VerifyAnalyzerAsync(source);
    }
    アナライザーを指定
    34
    

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35. using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task Foo()
    {
    var source = "";
    await Verify.VerifyAnalyzerAsync(source);
    }
    using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task Foo()
    {
    var source = "";
    await Verify.VerifyAnalyzerAsync(source);
    }
    アナライザーを指定
    35
    

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36. using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task Foo()
    {
    var source = "";
    await Verify.VerifyAnalyzerAsync(source);
    }
    using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task Foo()
    {
    var source = "";
    await Verify.VerifyAnalyzerAsync(source);
    }
    アナライザーを指定
    コンパイルエラー
    36
    

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37. using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task Foo()
    {
    var source = "";
    await Verify.VerifyAnalyzerAsync(source);
    }
    using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task Foo()
    {
    var source = "";
    await Verify.VerifyAnalyzerAsync(source);
    }
    引数が必要なアナライザーに対応できない！
    コンパイルエラー
    37
    

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38. using Dena.CodeAnalysis.CSharp.Testing;
    [Test]
    public async Task EmptySourceCode_NoDiagnosticReport()
    {
    const string source = "";
    var analyzer = new YourAnalyzer(new Component());
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    Assert.That(diagnostics.Length, Is.EqualTo(0));
    }
    using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task Foo()
    {
    var source = "";
    await Verify.VerifyAnalyzerAsync(source);
    }
    コンパイルエラー
    38
    

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39. using Dena.CodeAnalysis.CSharp.Testing;
    [Test]
    public async Task EmptySourceCode_NoDiagnosticReport()
    {
    const string source = "";
    var analyzer = new YourAnalyzer(new Component());
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    Assert.That(diagnostics.Length, Is.EqualTo(0));
    }
    using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task Foo()
    {
    var source = "";
    await Verify.VerifyAnalyzerAsync(source);
    }
    コンパイルエラー
    テストコード内で
    インスタンス化
    39
    

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40. using Dena.CodeAnalysis.CSharp.Testing;
    [Test]
    public async Task EmptySourceCode_NoDiagnosticReport()
    {
    const string source = "";
    var analyzer = new YourAnalyzer(new Component());
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    Assert.That(diagnostics.Length, Is.EqualTo(0));
    }
    using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task Foo()
    {
    var source = "";
    await Verify.VerifyAnalyzerAsync(source);
    }
    コンパイルエラー
    テストコード内で
    インスタンス化
    40
    

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41. Dena.CodeAnalysis.Testingができること
    ● アナライザーの実行とアサーションを分離させる
    ● 引数が必要なアナライザーを指定する
    ● 検査対象ソースコードから得られる情報を増やす
    41
    

    View Slide

42. 標準ライブラリを使った
    テストコード
    using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task TypeNameContainingLowercase_ReportOneDiagnostic()
    {
    var source = @"
    class TypeName
    {}
    ";
    await Verify.VerifyAnalyzerAsync(source);
    }
    42
    

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43. using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task TypeNameContainingLowercase_ReportOneDiagnostic()
    {
    var source = @"
    class TypeName
    {}
    ";
    await Verify.VerifyAnalyzerAsync(source);
    }
    検査対象ソースコード
    43
    

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44. using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task TypeNameContainingLowercase_ReportOneDiagnostic()
    {
    var source = @"
    class TypeName
    {}
    ";
    await Verify.VerifyAnalyzerAsync(source);
    }
    どこがエラー箇所？
    44
    

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45. using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task TypeNameContainingLowercase_ReportOneDiagnostic()
    {
    var source = @"
    class TypeName
    {}
    ";
    await Verify.VerifyAnalyzerAsync(source);
    }
    public async Task TypeNameContainingLowercase_ReportOneDiagnostic()
    {
    var analyzer = new RoslynAnalyzerTemplate();
    var (source, expected) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(@"
    namespace TypeNameContainingLowercase
    {
    class {|TypeName|RoslynAnalyzerTemplate0001|Type name 'TypeName' contains lowercase letters|}
    {
    }
    }");
    var actual = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    Assert.That(actual.Length, Is.EqualTo(expected.Count));
    Assert.That(actual.First().Id, Is.EqualTo(expected.First().Id))
    Assert.That(actual.First().GetMessage(), Is.EqualTo(expected.First().GetMessage()));
    Dena.CodeAnalysis.Testing
    を使ったテストコード
    45
    

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46. public async Task TypeNameContainingLowercase_ReportOneDiagnostic()
    {
    var analyzer = new RoslynAnalyzerTemplate();
    var (source, expected) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(@"
    namespace TypeNameContainingLowercase
    {
    class {|TypeName|RoslynAnalyzerTemplate0001|Type name 'TypeName' contains lowercase letters|}
    {
    }
    }");
    var actual = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    Assert.That(actual.Length, Is.EqualTo(expected.Count));
    Assert.That(actual.First().Id, Is.EqualTo(expected.First().Id))
    Assert.That(actual.First().GetMessage(), Is.EqualTo(expected.First().GetMessage()));
    using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task TypeNameContainingLowercase_ReportOneDiagnostic()
    {
    var source = @"
    class TypeName
    {}
    ";
    await Verify.VerifyAnalyzerAsync(source);
    }
    46
    

    View Slide

47. public async Task TypeNameContainingLowercase_ReportOneDiagnostic()
    {
    var analyzer = new RoslynAnalyzerTemplate();
    var (source, expected) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(@"
    namespace TypeNameContainingLowercase
    {
    class {|TypeName|RoslynAnalyzerTemplate0001|Type name 'TypeName' contains lowercase letters|}
    {
    }
    }");
    var actual = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    Assert.That(actual.Length, Is.EqualTo(expected.Count));
    Assert.That(actual.First().Id, Is.EqualTo(expected.First().Id))
    Assert.That(actual.First().GetMessage(), Is.EqualTo(expected.First().GetMessage()));
    using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task TypeNameContainingLowercase_ReportOneDiagnostic()
    {
    var source = @"
    class TypeName
    {}
    ";
    await Verify.VerifyAnalyzerAsync(source);
    }
    47
    エラー箇所
    

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48. public async Task TypeNameContainingLowercase_ReportOneDiagnostic()
    {
    var analyzer = new RoslynAnalyzerTemplate();
    var (source, expected) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(@"
    namespace TypeNameContainingLowercase
    {
    class {|TypeName|RoslynAnalyzerTemplate0001|Type name 'TypeName' contains lowercase letters|}
    {
    }
    }");
    var actual = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    Assert.That(actual.Length, Is.EqualTo(expected.Count));
    Assert.That(actual.First().Id, Is.EqualTo(expected.First().Id))
    Assert.That(actual.First().GetMessage(), Is.EqualTo(expected.First().GetMessage()));
    using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task TypeNameContainingLowercase_ReportOneDiagnostic()
    {
    var source = @"
    class TypeName
    {}
    ";
    await Verify.VerifyAnalyzerAsync(source);
    }
    48
    DDID
    エラー箇所
    

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49. public async Task TypeNameContainingLowercase_ReportOneDiagnostic()
    {
    var analyzer = new RoslynAnalyzerTemplate();
    var (source, expected) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(@"
    namespace TypeNameContainingLowercase
    {
    class {|TypeName|RoslynAnalyzerTemplate0001|Type name 'TypeName' contains lowercase letters|}
    {
    }
    }");
    var actual = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    Assert.That(actual.Length, Is.EqualTo(expected.Count));
    Assert.That(actual.First().Id, Is.EqualTo(expected.First().Id))
    Assert.That(actual.First().GetMessage(), Is.EqualTo(expected.First().GetMessage()));
    エラーメッセージ
    DDID
    エラー箇所
    using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task TypeNameContainingLowercase_ReportOneDiagnostic()
    {
    var source = @"
    class TypeName
    {}
    ";
    await Verify.VerifyAnalyzerAsync(source);
    }
    49
    

    View Slide

50. public async Task TypeNameContainingLowercase_ReportOneDiagnostic()
    {
    var analyzer = new RoslynAnalyzerTemplate();
    var (source, expected) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(@"
    namespace TypeNameContainingLowercase
    {
    class {|TypeName|RoslynAnalyzerTemplate0001|Type name 'TypeName' contains lowercase letters|}
    {
    }
    }");
    var actual = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    Assert.That(actual.Length, Is.EqualTo(expected.Count));
    Assert.That(actual.First().Id, Is.EqualTo(expected.First().Id))
    Assert.That(actual.First().GetMessage(), Is.EqualTo(expected.First().GetMessage()));
    書式を基に期待結果
    を作成
    作成された期待結果を利用
    using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task TypeNameContainingLowercase_ReportOneDiagnostic()
    {
    var source = @"
    class TypeName
    {}
    ";
    await Verify.VerifyAnalyzerAsync(source);
    }
    

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51. public async Task TypeNameContainingLowercase_ReportOneDiagnostic()
    {
    var analyzer = new RoslynAnalyzerTemplate();
    var (source, expected) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(@"
    namespace TypeNameContainingLowercase
    {
    class {|TypeName|RoslynAnalyzerTemplate0001|Type name 'TypeName' contains lowercase letters|}
    {
    }
    }");
    var actual = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    Assert.That(actual.Length, Is.EqualTo(expected.Count));
    Assert.That(actual.First().Id, Is.EqualTo(expected.First().Id))
    Assert.That(actual.First().GetMessage(), Is.EqualTo(expected.First().GetMessage()));
    書式を基に期待結果
    を作成
    using Verify =
    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier
    ;
    [Test]
    public async Task TypeNameContainingLowercase_ReportOneDiagnostic()
    {
    var source = @"
    class TypeName
    {}
    ";
    await Verify.VerifyAnalyzerAsync(source);
    }
    作成された期待結果を利用
    

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52. Let’s Try!
    実際にDena.CodeAnalysis.Testing
    を使ってテストを書いてみよう
    52
    

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53. アナライザーを作成するための準備
    1. テンプレートリポジトリを使ってアナライザーを作成
    a. https://github.com/DeNA/RoslynAnalyzerTemplate
    2. テンプレートに含まれるテストメソッドを削除する
    3. アナライザーのテンプレートを削除する
    53
    

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54. アナライザーを作成するための準備
    1. テンプレートリポジトリを使ってアナライザーを作成
    a. https://github.com/DeNA/RoslynAnalyzerTemplate
    2. テンプレートに含まれるテストメソッドを削除する
    3. アナライザーのテンプレートを削除する
    54
    デモリポジトリurl:
    https://github.com/DeNA/BanAsyncTaskAnalyzer
    該当コミットハッシュ:
    https://github.com/DeNA/BanAsyncTaskAnalyzer/commi
    t/0b2af3934a3a3759fbe25e73e527d4777b8a9d3b
    

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55. リファクタリング
    テストを追加する
    実装する
    テストを追加する
    TDDのモデル
    ✔Passed
    ❌Failed
    ✔Passed
    55
    

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56. public class C
    {
    public async Task Foo()
    {
    }
    }
    作成するアナライザー
    56
    

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57. public class C
    {
    public async Task Foo()
    {
    }
    }
    怒る
    ● async Task → async UniTask
    ● async void → async UniTaskVoid
    作成するアナライザー
    57
    

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58. public class C
    {
    public async Task Foo()
    {
    }
    }
    怒る
    ● async Task → async UniTask
    ● async void → async UniTaskVoid
    https://github.com/Cysharp/UniTask
    Copyright (c) 2019 Yoshifumi Kawai / Cysharp, Inc.
    作成するアナライザー
    58
    

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59. public class C
    {
    public async Task Foo()
    {
    }
    }
    動作
    BanAsyncTask0001 BanAsyncTask0002 何もレポートされない
    条件
    async使用関数
    System.Threading.Tasks.Task Y N N
    System.Void N Y N
    Cysharp.Threading.Tasks.UniTask N N Y
    NotSystem.Threading.Tasks.Task N N Y
    async未使用関数 System.Void N N Y
    怒る
    ● async Task → async UniTask
    ● async void → async UniTaskVoid
    作成するアナライザー
    59
    

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60. 動作
    BanAsyncTask0001 BanAsyncTask0002 何もレポートされない
    条件
    async使用関数
    System.Threading.Tasks.Task Y N N
    System.Void N Y N
    Cysharp.Threading.Tasks.UniTask N N Y
    NotSystem.Threading.Tasks.Task N N Y
    async未使用関数 System.Void N N Y
    作成するアナライザー
    60
    このケースを追加
    

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61. [Test]
    public async Task 非asyncメソッド_戻り値がvoid_何もレポートされない()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var source = ReadCodes("NoAsyncMethodCase.txt");
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actual = diagnostics
    .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
    .ToArray();
    DiagnosticsAssert.IsEmpty(actual);
    }
    61
    

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62. [Test]
    public async Task 非asyncメソッド_戻り値がvoid_何もレポートされない()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var source = ReadCodes("NoAsyncMethodCase.txt");
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actual = diagnostics
    .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
    .ToArray();
    DiagnosticsAssert.IsEmpty(actual);
    }
    class NoAsyncMethodCase
    {
    void NoAsyncMethod()
    {
    }
    }
    検査対象ソースコード
    62
    

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63. [Test]
    public async Task 非asyncメソッド_戻り値がvoid_何もレポートされない()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var source = ReadCodes("NoAsyncMethodCase.txt");
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actual = diagnostics
    .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
    .ToArray();
    DiagnosticsAssert.IsEmpty(actual);
    }
    private static string[] ReadCodes(params string[] sources)
    {
    const string Path = "../../../TestData";
    return sources.Select(file => File.ReadAllText($"{Path}/{file}", Encoding.UTF8)).ToArray();
    }
    63
    

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64. [Test]
    public async Task 非asyncメソッド_戻り値がvoid_何もレポートされない()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var source = ReadCodes("NoAsyncMethodCase.txt");
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actual = diagnostics
    .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
    .ToArray();
    DiagnosticsAssert.IsEmpty(actual);
    }
    検査対象ソースコードを渡し、アナライザーを実
    行
    64
    

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65. [Test]
    public async Task 非asyncメソッド_戻り値がvoid_何もレポートされない()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var source = ReadCodes("NoAsyncMethodCase.txt");
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actual = diagnostics
    .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
    .ToArray();
    DiagnosticsAssert.IsEmpty(actual);
    }
    65
    実際の値を加工している
    

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66. [Test]
    public async Task 非asyncメソッド_戻り値がvoid_何もレポートされない()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var source = ReadFromFile.ReadFile(TestData.GetPath("NoAsyncMethodCase.txt"));
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actual = diagnostics
    .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
    .ToArray();
    DiagnosticsAssert.IsEmpty(actual);
    }
    実際の値を加工している
    ✔Passed
    66
    

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67. [Test]
    public async Task 非asyncメソッド_戻り値がvoid_何もレポートされない()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var source = ReadFromFile.ReadFile(TestData.GetPath("NoAsyncMethodCase.txt"));
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actual = diagnostics
    .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
    .ToArray();
    DiagnosticsAssert.IsEmpty(actual);
    }
    実際の値を加工している
    Refactor
    Add Test
    67
    

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68. [Test]
    public async Task 非asyncメソッド_戻り値がvoid_何もレポートされない()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var source = ReadFromFile.ReadFile(TestData.GetPath("NoAsyncMethodCase.txt"));
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actual = diagnostics
    .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
    .ToArray();
    DiagnosticsAssert.IsEmpty(actual);
    }
    実際の値を加工している
    Refactor
    Add Test
    68
    

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69. 動作
    BanAsyncTask0001 BanAsyncTask0002 何もレポートされない
    条件
    async使用関数
    System.Threading.Tasks.Task Y N N
    System.Void N Y N
    Cysharp.Threading.Tasks.UniTask N N Y
    NotSystem.Threading.Tasks.Task N N Y
    async未使用関数 System.Void N N Y
    69
    

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70. 動作
    BanAsyncTask0001 BanAsyncTask0002 何もレポートされない
    条件
    async使用関数
    System.Threading.Tasks.Task Y N N
    System.Void N Y N
    Cysharp.Threading.Tasks.UniTask N N Y
    NotSystem.Threading.Tasks.Task N N Y
    async未使用関数 System.Void N N Y
    70
    このケースを追加
    

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71. [Test]
    public async Task asyncメソッド_戻り値がTask_BanAsyncTask0001がレポートされる()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var testData = ReadCodes("NoAsyncMethodCase.txt");
    var (source, expectedDiagnostics) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actualDiagnostics = diagnostics
    .Where(x => x.Id != "CS1591")
    .Where(x => x.Id != "CS8019")
    .ToArray();
    DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
    }
    テストメソッド
    71
    

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72. [Test]
    public async Task asyncメソッド_戻り値がTask_BanAsyncTask0001がレポートされる()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var testData = ReadCodes("NoAsyncMethodCase.txt");
    var (source, expectedDiagnostics) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actualDiagnostics = diagnostics
    .Where(x => x.Id != "CS1591")
    .Where(x => x.Id != "CS8019")
    .ToArray();
    DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
    }
    using System.Threading;
    using System.Threading.Tasks;
    namespace UseTask
    {
    class C
    {
    async Task {|UseTask|BanAsyncTask0001|Do not use 'System.Threading.Tasks.Task', Should use UniTask|}()
    {
    await Task.Delay(100);
    }
    }
    }
    検査対象ソースコード
    72
    

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73. [Test]
    public async Task asyncメソッド_戻り値がTask_BanAsyncTask0001がレポートされる()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var testData = ReadCodes("NoAsyncMethodCase.txt");
    var (source, expectedDiagnostics) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actualDiagnostics = diagnostics
    .Where(x => x.Id != "CS1591")
    .Where(x => x.Id != "CS8019")
    .ToArray();
    DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
    }
    using System.Threading;
    using System.Threading.Tasks;
    namespace UseTask
    {
    class C
    {
    async Task {|UseTask|BanAsyncTask0001|Do not use 'System.Threading.Tasks.Task', Should use UniTask|}()
    {
    await Task.Delay(100);
    }
    }
    }
    73
    レポート箇所
    

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74. [Test]
    public async Task asyncメソッド_戻り値がTask_BanAsyncTask0001がレポートされる()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var testData = ReadCodes("NoAsyncMethodCase.txt");
    var (source, expectedDiagnostics) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actualDiagnostics = diagnostics
    .Where(x => x.Id != "CS1591")
    .Where(x => x.Id != "CS8019")
    .ToArray();
    DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
    }
    using System.Threading;
    using System.Threading.Tasks;
    namespace UseTask
    {
    class C
    {
    async Task {|UseTask|BanAsyncTask0001|Do not use 'System.Threading.Tasks.Task', Should use UniTask|}()
    {
    await Task.Delay(100);
    }
    }
    }
    DDID
    74
    

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75. [Test]
    public async Task asyncメソッド_戻り値がTask_BanAsyncTask0001がレポートされる()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var testData = ReadCodes("NoAsyncMethodCase.txt");
    var (source, expectedDiagnostics) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actualDiagnostics = diagnostics
    .Where(x => x.Id != "CS1591")
    .Where(x => x.Id != "CS8019")
    .ToArray();
    DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
    }
    using System.Threading;
    using System.Threading.Tasks;
    namespace UseTask
    {
    class C
    {
    async Task {|UseTask|BanAsyncTask0001|Do not use 'System.Threading.Tasks.Task', Should use UniTask|}()
    {
    await Task.Delay(100);
    }
    }
    }
    75
    エラーメッセージ
    

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76. [Test]
    public async Task asyncメソッド_戻り値がTask_BanAsyncTask0001がレポートされる()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var testData = ReadCodes("NoAsyncMethodCase.txt");
    var (source, expectedDiagnostics) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actualDiagnostics = diagnostics
    .Where(x => x.Id != "CS1591")
    .Where(x => x.Id != "CS8019")
    .ToArray();
    DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
    }
    ソースコードと期
    待結果を作成
    76
    using System.Threading;
    using System.Threading.Tasks;
    namespace UseTask
    {
    class C
    {
    async Task {|UseTask|BanAsyncTask0001|Do not use 'System.Threading.Tasks.Task', Should use UniTask|}()
    {
    await Task.Delay(100);
    }
    }
    }
    

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77. [Test]
    public async Task asyncメソッド_戻り値がTask_BanAsyncTask0001がレポートされる()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var testData = ReadCodes("NoAsyncMethodCase.txt");
    var (source, expectedDiagnostics) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actualDiagnostics = diagnostics
    .Where(x => x.Id != "CS1591")
    .Where(x => x.Id != "CS8019")
    .ToArray();
    DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
    }
    ● Diagnosticのcollectionを順不同で比較
    ● 以下の観点がすべて一致するDIagnosticを等価と判断する
    ○ レポートされた問題のファイル内の位置（ファイルパス含む）
    ○ アナライザーのID
    ○ メッセージ
    77
    

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78. [Test]
    public async Task asyncメソッド_戻り値がTask_BanAsyncTask0001がレポートされる()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var testData = ReadCodes("NoAsyncMethodCase.txt");
    var (source, expectedDiagnostics) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actualDiagnostics = diagnostics
    .Where(x => x.Id != "CS1591")
    .Where(x => x.Id != "CS8019")
    .ToArray();
    DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
    }
    ● Diagnosticのcollectionを順不同で比較
    ● 以下の観点がすべて一致するDIagnosticを等価と判断する
    ○ レポートされた問題のファイル内の位置（ファイルパス含む）
    ○ アナライザーのID
    ○ メッセージ
    78
    ❌Failed
    

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79. [Test]
    public async Task asyncメソッド_戻り値がTask_BanAsyncTask0001がレポートされる()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var testData = ReadCodes("NoAsyncMethodCase.txt");
    var (source, expectedDiagnostics) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actualDiagnostics = diagnostics
    .Where(x => x.Id != "CS1591")
    .Where(x => x.Id != "CS8019")
    .ToArray();
    DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
    }
    Missing 1 diagnostics, extra 0 diagnostics of all 0 diagnostics:
    missing /0/Test0.cs: (7,18)-(7,25), BanAsyncTask0001, Do not use
    'System.Threading.Tasks.Task', Should use UniTask
    79
    

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80. [Test]
    public async Task asyncメソッド_戻り値がTask_BanAsyncTask0001がレポートされる()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var testData = ReadCodes("NoAsyncMethodCase.txt");
    var (source, expectedDiagnostics) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actualDiagnostics = diagnostics
    .Where(x => x.Id != "CS1591")
    .Where(x => x.Id != "CS8019")
    .ToArray();
    DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
    }
    Missing 1 diagnostics, extra 0 diagnostics of all 0 diagnostics:
    missing /0/Test0.cs: (7,18)-(7,25), BanAsyncTask0001, Do not use
    'System.Threading.Tasks.Task', Should use UniTask
    80
    レポート箇所
    

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81. [Test]
    public async Task asyncメソッド_戻り値がTask_BanAsyncTask0001がレポートされる()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var testData = ReadCodes("NoAsyncMethodCase.txt");
    var (source, expectedDiagnostics) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actualDiagnostics = diagnostics
    .Where(x => x.Id != "CS1591")
    .Where(x => x.Id != "CS8019")
    .ToArray();
    DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
    }
    Missing 1 diagnostics, extra 0 diagnostics of all 0 diagnostics:
    missing /0/Test0.cs: (7,18)-(7,25), BanAsyncTask0001, Do not use
    'System.Threading.Tasks.Task', Should use UniTask
    81
    DDID
    

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82. [Test]
    public async Task asyncメソッド_戻り値がTask_BanAsyncTask0001がレポートされる()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var testData = ReadCodes("NoAsyncMethodCase.txt");
    var (source, expectedDiagnostics) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actualDiagnostics = diagnostics
    .Where(x => x.Id != "CS1591")
    .Where(x => x.Id != "CS8019")
    .ToArray();
    DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
    }
    Missing 1 diagnostics, extra 0 diagnostics of all 0 diagnostics:
    missing /0/Test0.cs: (7,18)-(7,25), BanAsyncTask0001, Do not use
    'System.Threading.Tasks.Task', Should use UniTask
    82
    エラーメッセージ
    

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83. [Test]
    public async Task asyncメソッド_戻り値がTask_BanAsyncTask0001がレポートされる()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var testData = ReadCodes("NoAsyncMethodCase.txt");
    var (source, expectedDiagnostics) =
    TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actualDiagnostics = diagnostics
    .Where(x => x.Id != "CS1591")
    .Where(x => x.Id != "CS8019")
    .ToArray();
    DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
    }
    Missing 1 diagnostics, extra 0 diagnostics of all 0 diagnostics:
    missing /0/Test0.cs: (7,18)-(7,25), BanAsyncTask0001, Do not use
    'System.Threading.Tasks.Task', Should use UniTask
    83
    エラーメッセージ
    

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84. アナライザー本体を実装
    84
    

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85. using System.Collections.Immutable;
    using BanAsyncTaskAnalyzer.Extensions;
    using Microsoft.CodeAnalysis;
    using Microsoft.CodeAnalysis.Diagnostics;
    namespace BanAsyncTaskAnalyzer;
    [DiagnosticAnalyzer(LanguageNames.CSharp)]
    public class BanAsyncTaskAnalyzer : DiagnosticAnalyzer
    {
    private static readonly DiagnosticDescriptor Rule01 = new DiagnosticDescriptor(
    id: "BanAsyncTask0001",
    title: "Banned Task Rule",
    messageFormat: "Do not use '{0}', Should use UniTask",
    category: "Naming",
    defaultSeverity: DiagnosticSeverity.Warning,
    isEnabledByDefault: true,
    description: "Type names should be all uppercase.");
    public override ImmutableArray SupportedDiagnostics => ImmutableArray.Create(Rule01);
    public override void Initialize(AnalysisContext context)
    {
    context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
    context.EnableConcurrentExecution();
    context.RegisterSymbolAction(AnalyzeAsyncMethod, SymbolKind.Method);
    }
    private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
    {
    var methodSymbol = (IMethodSymbol)context.Symbol;
    if (!methodSymbol.IsAsync)
    {
    return;
    }
    if (methodSymbol.ReturnType.Name == "Task")
    {
    var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
    context.ReportDiagnostic(diagnostic);
    }
    }
    }
    アナライザー本体のソースコード
    85
    

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86. using System.Collections.Immutable;
    using BanAsyncTaskAnalyzer.Extensions;
    using Microsoft.CodeAnalysis;
    using Microsoft.CodeAnalysis.Diagnostics;
    namespace BanAsyncTaskAnalyzer;
    [DiagnosticAnalyzer(LanguageNames.CSharp)]
    public class BanAsyncTaskAnalyzer : DiagnosticAnalyzer
    {
    private static readonly DiagnosticDescriptor Rule01 = new DiagnosticDescriptor(
    id: "BanAsyncTask0001",
    title: "Banned Task Rule",
    messageFormat: "Do not use '{0}', Should use UniTask",
    category: "Naming",
    defaultSeverity: DiagnosticSeverity.Warning,
    isEnabledByDefault: true,
    description: "Type names should be all uppercase.");
    public override ImmutableArray SupportedDiagnostics => ImmutableArray.Create(Rule01);
    public override void Initialize(AnalysisContext context)
    {
    context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
    context.EnableConcurrentExecution();
    context.RegisterSymbolAction(AnalyzeAsyncMethod, SymbolKind.Method);
    }
    private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
    {
    var methodSymbol = (IMethodSymbol)context.Symbol;
    if (!methodSymbol.IsAsync)
    {
    return;
    }
    if (methodSymbol.ReturnType.Name == "Task")
    {
    var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
    context.ReportDiagnostic(diagnostic);
    }
    }
    }
    アナライザーのDiagnosticを定義
    86
    

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87. using System.Collections.Immutable;
    using BanAsyncTaskAnalyzer.Extensions;
    using Microsoft.CodeAnalysis;
    using Microsoft.CodeAnalysis.Diagnostics;
    namespace BanAsyncTaskAnalyzer;
    [DiagnosticAnalyzer(LanguageNames.CSharp)]
    public class BanAsyncTaskAnalyzer : DiagnosticAnalyzer
    {
    private static readonly DiagnosticDescriptor Rule01 = new DiagnosticDescriptor(
    id: "BanAsyncTask0001",
    title: "Banned Task Rule",
    messageFormat: "Do not use '{0}', Should use UniTask",
    category: "Naming",
    defaultSeverity: DiagnosticSeverity.Warning,
    isEnabledByDefault: true,
    description: "Type names should be all uppercase.");
    public override ImmutableArray SupportedDiagnostics => ImmutableArray.Create(Rule01);
    public override void Initialize(AnalysisContext context)
    {
    context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
    context.EnableConcurrentExecution();
    context.RegisterSymbolAction(AnalyzeAsyncMethod, SymbolKind.Method);
    }
    private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
    {
    var methodSymbol = (IMethodSymbol)context.Symbol;
    if (!methodSymbol.IsAsync)
    {
    return;
    }
    if (methodSymbol.ReturnType.Name == "Task")
    {
    var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
    context.ReportDiagnostic(diagnostic);
    }
    }
    }
    アナライザー本体の実装
    87
    

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88. using System.Collections.Immutable;
    using BanAsyncTaskAnalyzer.Extensions;
    using Microsoft.CodeAnalysis;
    using Microsoft.CodeAnalysis.Diagnostics;
    namespace BanAsyncTaskAnalyzer;
    [DiagnosticAnalyzer(LanguageNames.CSharp)]
    public class BanAsyncTaskAnalyzer : DiagnosticAnalyzer
    {
    private static readonly DiagnosticDescriptor Rule01 = new DiagnosticDescriptor(
    id: "BanAsyncTask0001",
    title: "Banned Task Rule",
    messageFormat: "Do not use '{0}', Should use UniTask",
    category: "Naming",
    defaultSeverity: DiagnosticSeverity.Warning,
    isEnabledByDefault: true,
    description: "Type names should be all uppercase.");
    public override ImmutableArray SupportedDiagnostics => ImmutableArray.Create(Rule01);
    public override void Initialize(AnalysisContext context)
    {
    context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
    context.EnableConcurrentExecution();
    context.RegisterSymbolAction(AnalyzeAsyncMethod, SymbolKind.Method);
    }
    private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
    {
    var methodSymbol = (IMethodSymbol)context.Symbol;
    if (!methodSymbol.IsAsync)
    {
    return;
    }
    if (methodSymbol.ReturnType.Name == "Task")
    {
    var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
    context.ReportDiagnostic(diagnostic);
    }
    }
    }
    88
    定義されたメソッドに関する情報を取得
    

    View Slide

89. using System.Collections.Immutable;
    using BanAsyncTaskAnalyzer.Extensions;
    using Microsoft.CodeAnalysis;
    using Microsoft.CodeAnalysis.Diagnostics;
    namespace BanAsyncTaskAnalyzer;
    [DiagnosticAnalyzer(LanguageNames.CSharp)]
    public class BanAsyncTaskAnalyzer : DiagnosticAnalyzer
    {
    private static readonly DiagnosticDescriptor Rule01 = new DiagnosticDescriptor(
    id: "BanAsyncTask0001",
    title: "Banned Task Rule",
    messageFormat: "Do not use '{0}', Should use UniTask",
    category: "Naming",
    defaultSeverity: DiagnosticSeverity.Warning,
    isEnabledByDefault: true,
    description: "Type names should be all uppercase.");
    public override ImmutableArray SupportedDiagnostics => ImmutableArray.Create(Rule01);
    public override void Initialize(AnalysisContext context)
    {
    context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
    context.EnableConcurrentExecution();
    context.RegisterSymbolAction(AnalyzeAsyncMethod, SymbolKind.Method);
    }
    private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
    {
    var methodSymbol = (IMethodSymbol)context.Symbol;
    if (!methodSymbol.IsAsync)
    {
    return;
    }
    if (methodSymbol.ReturnType.Name == "Task")
    {
    var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
    context.ReportDiagnostic(diagnostic);
    }
    }
    }
    解析対象がAsyncメソッド以外ならreturn
    89
    

    View Slide

90. using System.Collections.Immutable;
    using BanAsyncTaskAnalyzer.Extensions;
    using Microsoft.CodeAnalysis;
    using Microsoft.CodeAnalysis.Diagnostics;
    namespace BanAsyncTaskAnalyzer;
    [DiagnosticAnalyzer(LanguageNames.CSharp)]
    public class BanAsyncTaskAnalyzer : DiagnosticAnalyzer
    {
    private static readonly DiagnosticDescriptor Rule01 = new DiagnosticDescriptor(
    id: "BanAsyncTask0001",
    title: "Banned Task Rule",
    messageFormat: "Do not use '{0}', Should use UniTask",
    category: "Naming",
    defaultSeverity: DiagnosticSeverity.Warning,
    isEnabledByDefault: true,
    description: "Type names should be all uppercase.");
    public override ImmutableArray SupportedDiagnostics => ImmutableArray.Create(Rule01);
    public override void Initialize(AnalysisContext context)
    {
    context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
    context.EnableConcurrentExecution();
    context.RegisterSymbolAction(AnalyzeAsyncMethod, SymbolKind.Method);
    }
    private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
    {
    var methodSymbol = (IMethodSymbol)context.Symbol;
    if (!methodSymbol.IsAsync)
    {
    return;
    }
    if (methodSymbol.ReturnType.Name == "Task")
    {
    var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
    context.ReportDiagnostic(diagnostic);
    }
    }
    }
    定義されたメソッドの戻り値の型名が
    ”Task”だったらレポートする 90
    

    View Slide

91. using System.Collections.Immutable;
    using BanAsyncTaskAnalyzer.Extensions;
    using Microsoft.CodeAnalysis;
    using Microsoft.CodeAnalysis.Diagnostics;
    namespace BanAsyncTaskAnalyzer;
    [DiagnosticAnalyzer(LanguageNames.CSharp)]
    public class BanAsyncTaskAnalyzer : DiagnosticAnalyzer
    {
    private static readonly DiagnosticDescriptor Rule01 = new DiagnosticDescriptor(
    id: "BanAsyncTask0001",
    title: "Banned Task Rule",
    messageFormat: "Do not use '{0}', Should use UniTask",
    category: "Naming",
    defaultSeverity: DiagnosticSeverity.Warning,
    isEnabledByDefault: true,
    description: "Type names should be all uppercase.");
    public override ImmutableArray SupportedDiagnostics => ImmutableArray.Create(Rule01);
    public override void Initialize(AnalysisContext context)
    {
    context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
    context.EnableConcurrentExecution();
    context.RegisterSymbolAction(AnalyzeAsyncMethod, SymbolKind.Method);
    }
    private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
    {
    var methodSymbol = (IMethodSymbol)context.Symbol;
    if (!methodSymbol.IsAsync)
    {
    return;
    }
    if (methodSymbol.ReturnType.Name == "Task")
    {
    var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
    context.ReportDiagnostic(diagnostic);
    }
    }
    }
    91
    ✔Passed
    

    View Slide

92. using System.Collections.Immutable;
    using BanAsyncTaskAnalyzer.Extensions;
    using Microsoft.CodeAnalysis;
    using Microsoft.CodeAnalysis.Diagnostics;
    namespace BanAsyncTaskAnalyzer;
    [DiagnosticAnalyzer(LanguageNames.CSharp)]
    public class BanAsyncTaskAnalyzer : DiagnosticAnalyzer
    {
    private static readonly DiagnosticDescriptor Rule01 = new DiagnosticDescriptor(
    id: "BanAsyncTask0001",
    title: "Banned Task Rule",
    messageFormat: "Do not use '{0}', Should use UniTask",
    category: "Naming",
    defaultSeverity: DiagnosticSeverity.Warning,
    isEnabledByDefault: true,
    description: "Type names should be all uppercase.");
    public override ImmutableArray SupportedDiagnostics => ImmutableArray.Create(Rule01);
    public override void Initialize(AnalysisContext context)
    {
    context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
    context.EnableConcurrentExecution();
    context.RegisterSymbolAction(AnalyzeAsyncMethod, SymbolKind.Method);
    }
    private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
    {
    var methodSymbol = (IMethodSymbol)context.Symbol;
    if (!methodSymbol.IsAsync)
    {
    return;
    }
    if (methodSymbol.ReturnType.Name == "Task")
    {
    var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
    context.ReportDiagnostic(diagnostic);
    }
    }
    }
    92
    Refactor
    Add Test
    

    View Slide

93. using System.Collections.Immutable;
    using BanAsyncTaskAnalyzer.Extensions;
    using Microsoft.CodeAnalysis;
    using Microsoft.CodeAnalysis.Diagnostics;
    namespace BanAsyncTaskAnalyzer;
    [DiagnosticAnalyzer(LanguageNames.CSharp)]
    public class BanAsyncTaskAnalyzer : DiagnosticAnalyzer
    {
    private static readonly DiagnosticDescriptor Rule01 = new DiagnosticDescriptor(
    id: "BanAsyncTask0001",
    title: "Banned Task Rule",
    messageFormat: "Do not use '{0}', Should use UniTask",
    category: "Naming",
    defaultSeverity: DiagnosticSeverity.Warning,
    isEnabledByDefault: true,
    description: "Type names should be all uppercase.");
    public override ImmutableArray SupportedDiagnostics => ImmutableArray.Create(Rule01);
    public override void Initialize(AnalysisContext context)
    {
    context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
    context.EnableConcurrentExecution();
    context.RegisterSymbolAction(AnalyzeAsyncMethod, SymbolKind.Method);
    }
    private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
    {
    var methodSymbol = (IMethodSymbol)context.Symbol;
    if (!methodSymbol.IsAsync)
    {
    return;
    }
    if (methodSymbol.ReturnType.Name == "Task")
    {
    var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
    context.ReportDiagnostic(diagnostic);
    }
    }
    }
    93
    Refactor
    Add Test
    

    View Slide

94. 動作
    BanAsyncTask0001 BanAsyncTask0002 何もレポートされない
    条件
    async使用関数
    System.Threading.Tasks.Task Y N N
    System.Void N Y N
    Cysharp.Threading.Tasks.UniTask N N Y
    NotSystem.Threading.Tasks.Task N N Y
    async未使用関数 System.Void N N Y
    94
    

    View Slide

95. 動作
    BanAsyncTask0001 BanAsyncTask0002 何もレポートされない
    条件
    async使用関数
    System.Threading.Tasks.Task Y N N
    System.Void N Y N
    Cysharp.Threading.Tasks.UniTask N N Y
    NotSystem.Threading.Tasks.Task N N Y
    async未使用関数 System.Void N N Y
    95
    このケースを追加
    

    View Slide

96. public async Task asyncメソッド_戻り値がDummyTask_何もレポートされない()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var source = ReadCodes("UseDummyTaskCase.txt", "Fakes.cs");
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actual = diagnostics
    .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
    .Where(x => x.Id != "CS1998") // Ignore "This async method lacks 'await' operators and will run
    synchronously".
    .ToArray();
    DiagnosticsAssert.IsEmpty(actual);
    }
    テストメソッド
    96
    

    View Slide

97. public async Task asyncメソッド_戻り値がDummyTask_何もレポートされない()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var source = ReadCodes("UseDummyTaskCase.txt", "Fakes.cs");
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actual = diagnostics
    .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
    .Where(x => x.Id != "CS1998") // Ignore "This async method lacks 'await' operators and will run
    synchronously".
    .ToArray();
    DiagnosticsAssert.IsEmpty(actual);
    }
    using NotSystem.Threading.Tasks;
    namespace UseDummyTask
    {
    class C
    {
    async Task UseDummyTask()
    {
    }
    }
    }
    検査対象ソースコード
    97
    

    View Slide

98. public async Task asyncメソッド_戻り値がDummyTask_何もレポートされない()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var source = ReadCodes("UseDummyTaskCase.txt", "Fakes.cs");
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actual = diagnostics
    .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
    .Where(x => x.Id != "CS1998") // Ignore "This async method lacks 'await' operators and will run
    synchronously".
    .ToArray();
    DiagnosticsAssert.IsEmpty(actual);
    }
    using NotSystem.Threading.Tasks;
    namespace UseDummyTask
    {
    class C
    {
    async Task UseDummyTask()
    {
    }
    }
    }
    98
    ”Task”という名前の、asyncメソッドの
    戻り値になる型を持つnamespace
    

    View Slide

99. public async Task asyncメソッド_戻り値がDummyTask_何もレポートされない()
    {
    var analyzer = new BanAsyncTaskAnalyzer();
    var source = ReadCodes("UseDummyTaskCase.txt", "Fakes.cs");
    var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
    var actual = diagnostics
    .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
    .Where(x => x.Id != "CS1998") // Ignore "This async method lacks 'await' operators and will run
    synchronously".
    .ToArray();
    DiagnosticsAssert.IsEmpty(actual);
    }
    99
    namespace NotSystem.Threading.Tasks
    {
    [AsyncMethodBuilder(typeof(CompilerServices.AsyncUniTaskMethodBuil
    der))]
    public struct Task
    {
    }
    public class CompilerServices
    {
    public class AsyncUniTaskMethodBuilder
    {
    }
    }
    }
    ダミー実装
    

    View Slide

100. public async Task asyncメソッド_戻り値がDummyTask_何もレポートされない()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var source = ReadCodes("UseDummyTaskCase.txt", "Fakes.cs");
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actual = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS1998") // Ignore "This async method lacks 'await' operators and will run
     synchronously".
     .ToArray();
     DiagnosticsAssert.IsEmpty(actual);
     }
     ダミー実装と検査対象ソースコードを
     渡しアナライザーを実行
     100
     

     View Slide

101. 101
     public async Task asyncメソッド_戻り値がDummyTask_何もレポートされない()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var source = ReadCodes("UseDummyTaskCase.txt", "Fakes.cs");
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actual = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS1998") // Ignore "This async method lacks 'await' operators and will run
     synchronously".
     .ToArray();
     DiagnosticsAssert.IsEmpty(actual);
     }
     Diagnosticが存在しないことを検証できるカスタムアサーション
     出力形式は、前述したDiagnosticsAssert.AreEqualと同じ
     

     View Slide

102. 102
     public async Task asyncメソッド_戻り値がDummyTask_何もレポートされない()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var source = ReadCodes("UseDummyTaskCase.txt", "Fakes.cs");
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actual = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS1998") // Ignore "This async method lacks 'await' operators and will run
     synchronously".
     .ToArray();
     DiagnosticsAssert.IsEmpty(actual);
     }
     Diagnosticが存在しないことを検証できるカスタムアサーション
     出力形式は、前述したDiagnosticsAssert.AreEqualと同じ
     ❌Failed
     

     View Slide

103. 103
     public async Task asyncメソッド_戻り値がDummyTask_何もレポートされない()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var source = ReadCodes("UseDummyTaskCase.txt", "Fakes.cs");
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actual = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS1998") // Ignore "This async method lacks 'await' operators and will run
     synchronously".
     .ToArray();
     DiagnosticsAssert.IsEmpty(actual);
     }
     expected no diagnostics, but 1 diagnostics are reported
     extra /0/Test0.cs: (4,15)-(4,27), BanAsyncTask0001,
     Do not use 'NotSystem.Threading.Tasks.Task', Should use UniTask
     

     View Slide

104. if (methodSymbol.ReturnType.Name == "Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     変更前
     アナライザー本体のコード
     104
     

     View Slide

105. if (methodSymbol.ReturnType.Name == "Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     変更前
     完全修飾型名を見ていない
     105
     

     View Slide

106. if (methodSymbol.ReturnType.Name == "Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     変更前
     完全修飾型名を見ていない
     106
     

     View Slide

107. if (methodSymbol.ReturnType.Name == "Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     変更前
     完全修飾型名を見ていない
     System.Threading.Tasks.Task
     完全修飾型名
     107
     

     View Slide

108. if (methodSymbol.ReturnType.Name == "Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     変更前
     完全修飾型名を見ていない
     System.Threading.Tasks.Task
     現実装
     108
     

     View Slide

109. if (methodSymbol.ReturnType.Name == "Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     変更前
     完全修飾型名を見ていない
     System.Threading.Tasks.Task
     現実装
     109
     

     View Slide

110. if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     if (methodSymbol.ReturnType.Name == "Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     変更後
     変更前
     完全修飾型名を見ていない
     110
     

     View Slide

111. if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     if (methodSymbol.ReturnType.Name == "Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     変更後
     変更前
     完全修飾型名を見ていない
     完全修飾型名を見る
     111
     

     View Slide

112. if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     if (methodSymbol.ReturnType.Name == "Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     変更後
     変更前
     using System.Collections.Generic;
     using Microsoft.CodeAnalysis;
     namespace BanAsyncTaskAnalyzer.Extensions;
     public static class NamespaceOrTypeSymbolExtensions
     {
     public static string FullName(this INamespaceOrTypeSymbol symbol)
     {
     var collectedNamespace = new List();
     while (symbol.Name != "")
     {
     collectedNamespace.Add(symbol.Name);
     symbol = symbol.ContainingNamespace;
     }
     collectedNamespace.Reverse();
     return string.Join(".", collectedNamespace);
     }
     }
     完全修飾型名を取得する
     拡張メソッド
     112
     

     View Slide

113. if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task"
     )
     {
     var diagnostic = Diagnostic.Create(
     Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     if (methodSymbol.ReturnType.Name == "Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     変更後
     変更前
     using System.Collections.Generic;
     using Microsoft.CodeAnalysis;
     namespace BanAsyncTaskAnalyzer.Extensions;
     public static class NamespaceOrTypeSymbolExtensions
     {
     public static string FullName(this INamespaceOrTypeSymbol symbol)
     {
     var collectedNamespace = new List();
     while (symbol.Name != "")
     {
     collectedNamespace.Add(symbol.Name);
     symbol = symbol.ContainingNamespace;
     }
     collectedNamespace.Reverse();
     return string.Join(".", collectedNamespace);
     }
     }
     ✔Passed
     113
     

     View Slide

114. if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task"
     )
     {
     var diagnostic = Diagnostic.Create(
     Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     if (methodSymbol.ReturnType.Name == "Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     変更後
     変更前
     using System.Collections.Generic;
     using Microsoft.CodeAnalysis;
     namespace BanAsyncTaskAnalyzer.Extensions;
     public static class NamespaceOrTypeSymbolExtensions
     {
     public static string FullName(this INamespaceOrTypeSymbol symbol)
     {
     var collectedNamespace = new List();
     while (symbol.Name != "")
     {
     collectedNamespace.Add(symbol.Name);
     symbol = symbol.ContainingNamespace;
     }
     collectedNamespace.Reverse();
     return string.Join(".", collectedNamespace);
     }
     }
     Refactor
     Add Test
     114
     

     View Slide

115. if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task"
     )
     {
     var diagnostic = Diagnostic.Create(
     Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     if (methodSymbol.ReturnType.Name == "Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     変更後
     変更前
     using System.Collections.Generic;
     using Microsoft.CodeAnalysis;
     namespace BanAsyncTaskAnalyzer.Extensions;
     public static class NamespaceOrTypeSymbolExtensions
     {
     public static string FullName(this INamespaceOrTypeSymbol symbol)
     {
     var collectedNamespace = new List();
     while (symbol.Name != "")
     {
     collectedNamespace.Add(symbol.Name);
     symbol = symbol.ContainingNamespace;
     }
     collectedNamespace.Reverse();
     return string.Join(".", collectedNamespace);
     }
     }
     Refactor
     Add Test
     115
     

     View Slide

116. 動作
     BanAsyncTask0001 BanAsyncTask0002 何もレポートされない
     条件
     async使用関数
     System.Threading.Tasks.Task Y N N
     System.Void N Y N
     Cysharp.Threading.Tasks.UniTask N N Y
     NotSystem.Threading.Tasks.Task N N Y
     async未使用関数 System.Void N N Y
     116
     

     View Slide

117. 動作
     BanAsyncTask0001 BanAsyncTask0002 何もレポートされない
     条件
     async使用関数
     System.Threading.Tasks.Task Y N N
     System.Void N Y N
     Cysharp.Threading.Tasks.UniTask N N Y
     NotSystem.Threading.Tasks.Task N N Y
     async未使用関数 System.Void N N Y
     117
     このケースを追加
     

     View Slide

118. public async Task asyncメソッド_戻り値がUniTask_何もレポートされない()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var source = ReadCodes("UseUniTaskCase.txt", "Fakes.cs");
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actual = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS1998") // Ignore "This async method lacks 'await' operators and will run
     synchronously".
     .ToArray();
     DiagnosticsAssert.IsEmpty(actual);
     }
     テストメソッド
     118
     

     View Slide

119. public async Task asyncメソッド_戻り値がUniTask_何もレポートされない()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var source = ReadCodes("UseUniTaskCase.txt", "Fakes.cs");
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actual = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS1998") // Ignore "This async method lacks 'await' operators and will run
     synchronously".
     .ToArray();
     DiagnosticsAssert.IsEmpty(actual);
     }
     119
     using Cysharp.Threading.Tasks;
     class C
     {
     async UniTask UseUniTask()
     {
     }
     }
     検査対象ソースコード
     

     View Slide

120. public async Task asyncメソッド_戻り値がUniTask_何もレポートされない()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var source = ReadCodes("UseUniTaskCase.txt", "Fakes.cs");
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actual = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS1998") // Ignore "This async method lacks 'await' operators and will run
     synchronously".
     .ToArray();
     DiagnosticsAssert.IsEmpty(actual);
     }
     120
     using Cysharp.Threading.Tasks;
     class C
     {
     async UniTask UseUniTask()
     {
     }
     }
     UniTaskの
     namespaceを指定
     

     View Slide

121. public async Task asyncメソッド_戻り値がUniTask_何もレポートされない()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var source = ReadCodes("UseUniTaskCase.txt", "Fakes.cs");
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actual = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS1998") // Ignore "This async method lacks 'await' operators and will run
     synchronously".
     .ToArray();
     DiagnosticsAssert.IsEmpty(actual);
     }
     121
     using Cysharp.Threading.Tasks;
     class C
     {
     async UniTask UseUniTask()
     {
     }
     }
     using System.Runtime.CompilerServices;
     namespace Cysharp.Threading.Tasks
     {
     [AsyncMethodBuilder(typeof(CompilerServices.AsyncUniTaskMethodBuilder))]
     public struct UniTask
     {
     }
     [AsyncMethodBuilder(typeof(CompilerServices.AsyncUniTaskMethodBuilder))]
     public struct UniTaskVoid
     {
     }
     }
     namespace Cysharp.Threading.Tasks.CompilerServices
     {
     public struct AsyncUniTaskMethodBuilder
     {
     }
     }
     UniTaskの
     ダミー実装
     

     View Slide

122. public async Task asyncメソッド_戻り値がUniTask_何もレポートされない()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var source = ReadCodes("UseUniTaskCase.txt", "Fakes.cs");
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actual = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS1998") // Ignore "This async method lacks 'await' operators and will run
     synchronously".
     .ToArray();
     DiagnosticsAssert.IsEmpty(actual);
     }
     122
     using Cysharp.Threading.Tasks;
     class C
     {
     async UniTask UseUniTask()
     {
     }
     }
     using System.Runtime.CompilerServices;
     namespace Cysharp.Threading.Tasks
     {
     [AsyncMethodBuilder(typeof(CompilerServices.AsyncUniTaskMethodBuilder))]
     public struct UniTask
     {
     }
     [AsyncMethodBuilder(typeof(CompilerServices.AsyncUniTaskMethodBuilder))]
     public struct UniTaskVoid
     {
     }
     }
     namespace Cysharp.Threading.Tasks.CompilerServices
     {
     public struct AsyncUniTaskMethodBuilder
     {
     }
     }
     ✔Passed
     

     View Slide

123. public async Task asyncメソッド_戻り値がUniTask_何もレポートされない()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var source = ReadCodes("UseUniTaskCase.txt", "Fakes.cs");
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actual = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS1998") // Ignore "This async method lacks 'await' operators and will run
     synchronously".
     .ToArray();
     DiagnosticsAssert.IsEmpty(actual);
     }
     123
     using Cysharp.Threading.Tasks;
     class C
     {
     async UniTask UseUniTask()
     {
     }
     }
     using System.Runtime.CompilerServices;
     namespace Cysharp.Threading.Tasks
     {
     [AsyncMethodBuilder(typeof(CompilerServices.AsyncUniTaskMethodBuilder))]
     public struct UniTask
     {
     }
     [AsyncMethodBuilder(typeof(CompilerServices.AsyncUniTaskMethodBuilder))]
     public struct UniTaskVoid
     {
     }
     }
     namespace Cysharp.Threading.Tasks.CompilerServices
     {
     public struct AsyncUniTaskMethodBuilder
     {
     }
     }
     Refactor
     Add Test
     

     View Slide

124. public async Task asyncメソッド_戻り値がUniTask_何もレポートされない()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var source = ReadCodes("UseUniTaskCase.txt", "Fakes.cs");
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actual = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS1998") // Ignore "This async method lacks 'await' operators and will run
     synchronously".
     .ToArray();
     DiagnosticsAssert.IsEmpty(actual);
     }
     124
     using Cysharp.Threading.Tasks;
     class C
     {
     async UniTask UseUniTask()
     {
     }
     }
     using System.Runtime.CompilerServices;
     namespace Cysharp.Threading.Tasks
     {
     [AsyncMethodBuilder(typeof(CompilerServices.AsyncUniTaskMethodBuilder))]
     public struct UniTask
     {
     }
     [AsyncMethodBuilder(typeof(CompilerServices.AsyncUniTaskMethodBuilder))]
     public struct UniTaskVoid
     {
     }
     }
     namespace Cysharp.Threading.Tasks.CompilerServices
     {
     public struct AsyncUniTaskMethodBuilder
     {
     }
     }
     Refactor
     Add Test
     

     View Slide

125. 動作
     BanAsyncTask0001 BanAsyncTask0002 何もレポートされない
     条件
     async使用関数
     System.Threading.Tasks.Task Y N N
     System.Void N Y N
     Cysharp.Threading.Tasks.UniTask N N Y
     NotSystem.Threading.Tasks.Task N N Y
     async未使用関数 System.Void N N Y
     125
     

     View Slide

126. 動作
     BanAsyncTask0001 BanAsyncTask0002 何もレポートされない
     条件
     async使用関数
     System.Threading.Tasks.Task Y N N
     System.Void N Y N
     Cysharp.Threading.Tasks.UniTask N N Y
     NotSystem.Threading.Tasks.Task N N Y
     async未使用関数 System.Void N N Y
     このケースを追加
     126
     

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127. [Test]
     public async Task asyncメソッド_戻り値がvoid_BanAsyncTask0002がレポートされる()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var testData = ReadCodes("AsyncVoidCase.txt");
     var (source, expectedDiagnostics) = TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actualDiagnostics = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS8019") // Ignore "Unnecessary using directive"
     .Where(x => x.Id !=
     "CS1998") // Ignore "This async method lacks 'await' operators and will run synchronously."
     .ToArray();
     DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
     }
     127
     

     View Slide

128. [Test]
     public async Task asyncメソッド_戻り値がvoid_BanAsyncTask0002がレポートされる()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var testData = ReadCodes("AsyncVoidCase.txt");
     var (source, expectedDiagnostics) = TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actualDiagnostics = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS8019") // Ignore "Unnecessary using directive"
     .Where(x => x.Id !=
     "CS1998") // Ignore "This async method lacks 'await' operators and will run synchronously."
     .ToArray();
     DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
     }
     128
     using System.Threading;
     using System.Threading.Tasks;
     namespace UseTask
     {
     class C
     {
     async void {|UseAsyncVoid|BanAsyncTask0002|Do not use 'void' in async Method, Should use UniTaskVoid|}()
     {
     await Task.Delay(100);
     }
     }
     }
     検査対象ソースコード
     

     View Slide

129. [Test]
     public async Task asyncメソッド_戻り値がvoid_BanAsyncTask0002がレポートされる()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var testData = ReadCodes("AsyncVoidCase.txt");
     var (source, expectedDiagnostics) = TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actualDiagnostics = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS8019") // Ignore "Unnecessary using directive"
     .Where(x => x.Id !=
     "CS1998") // Ignore "This async method lacks 'await' operators and will run synchronously."
     .ToArray();
     DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
     }
     129
     using System.Threading;
     using System.Threading.Tasks;
     namespace UseTask
     {
     class C
     {
     async void {|UseAsyncVoid|BanAsyncTask0002|Do not use 'void' in async Method, Should use UniTaskVoid|}()
     {
     await Task.Delay(100);
     }
     }
     } レポート箇所
     

     View Slide

130. [Test]
     public async Task asyncメソッド_戻り値がvoid_BanAsyncTask0002がレポートされる()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var testData = ReadCodes("AsyncVoidCase.txt");
     var (source, expectedDiagnostics) = TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actualDiagnostics = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS8019") // Ignore "Unnecessary using directive"
     .Where(x => x.Id !=
     "CS1998") // Ignore "This async method lacks 'await' operators and will run synchronously."
     .ToArray();
     DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
     }
     130
     using System.Threading;
     using System.Threading.Tasks;
     namespace UseTask
     {
     class C
     {
     async void {|UseAsyncVoid|BanAsyncTask0002|Do not use 'void' in async Method, Should use UniTaskVoid|}()
     {
     await Task.Delay(100);
     }
     }
     } DDID
     

     View Slide

131. [Test]
     public async Task asyncメソッド_戻り値がvoid_BanAsyncTask0002がレポートされる()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var testData = ReadCodes("AsyncVoidCase.txt");
     var (source, expectedDiagnostics) = TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actualDiagnostics = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS8019") // Ignore "Unnecessary using directive"
     .Where(x => x.Id !=
     "CS1998") // Ignore "This async method lacks 'await' operators and will run synchronously."
     .ToArray();
     DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
     }
     131
     using System.Threading;
     using System.Threading.Tasks;
     namespace UseTask
     {
     class C
     {
     async void {|UseAsyncVoid|BanAsyncTask0002|Do not use 'void' in async Method, Should use UniTaskVoid|}()
     {
     await Task.Delay(100);
     }
     }
     } エラーメッセージ
     

     View Slide

132. using System.Threading;
     using System.Threading.Tasks;
     namespace UseTask
     {
     class C
     {
     async void {|UseAsyncVoid|BanAsyncTask0002|Do not use 'void' in async Method, Should use UniTaskVoid|}()
     {
     await Task.Delay(100);
     }
     }
     }
     [Test]
     public async Task asyncメソッド_戻り値がvoid_BanAsyncTask0002がレポートされる()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var testData = ReadCodes("AsyncVoidCase.txt");
     var (source, expectedDiagnostics) = TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actualDiagnostics = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS8019") // Ignore "Unnecessary using directive"
     .Where(x => x.Id !=
     "CS1998") // Ignore "This async method lacks 'await' operators and will run synchronously."
     .ToArray();
     DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
     }
     ❌Failed
     132
     

     View Slide

133. [Test]
     public async Task asyncメソッド_戻り値がvoid_BanAsyncTask0002がレポートされる()
     {
     var analyzer = new BanAsyncTaskAnalyzer();
     var testData = ReadCodes("AsyncVoidCase.txt");
     var (source, expectedDiagnostics) = TestDataParser.CreateSourceAndExpectedDiagnostic(testData[0]);
     var diagnostics = await DiagnosticAnalyzerRunner.Run(analyzer, source);
     var actualDiagnostics = diagnostics
     .Where(x => x.Id != "CS1591") // Ignore "Missing XML comment for publicly visible type or member"
     .Where(x => x.Id != "CS8019") // Ignore "Unnecessary using directive"
     .Where(x => x.Id !=
     "CS1998") // Ignore "This async method lacks 'await' operators and will run synchronously."
     .ToArray();
     DiagnosticsAssert.AreEqual(expectedDiagnostics, actualDiagnostics);
     }
     133
     extra 0 diagnostics of all 0 diagnostics:
     missing /0/Test0.cs: (7,18)-(7,30), BanAsyncTask0002, Do not use
     'void' in async Method, Should use UniTaskVoid
     

     View Slide

134. アナライザー本体を実装
     134
     

     View Slide

135. private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
     {
     var methodSymbol = (IMethodSymbol)context.Symbol;
     if (!methodSymbol.IsAsync)
     {
     return;
     }
     if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     }
     変更前
     アナライザー本体のソースコード
     135
     

     View Slide

136. private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
     {
     var methodSymbol = (IMethodSymbol)context.Symbol;
     if (!methodSymbol.IsAsync)
     {
     return;
     }
     if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     }
     変更前
     void型の指定を検知できない
     136
     

     View Slide

137. private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
     {
     var methodSymbol = (IMethodSymbol)context.Symbol;
     if (!methodSymbol.IsAsync)
     {
     return;
     }
     if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     if (methodSymbol.ReturnType.FullName() == "System.Void")
     {
     var diagnostic = Diagnostic.Create(Rule02, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     }
     }
     private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
     {
     var methodSymbol = (IMethodSymbol)context.Symbol;
     if (!methodSymbol.IsAsync)
     {
     return;
     }
     if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     }
     ✔変更後
     変更前
     137
     

     View Slide

138. private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
     {
     var methodSymbol = (IMethodSymbol)context.Symbol;
     if (!methodSymbol.IsAsync)
     {
     return;
     }
     if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     if (methodSymbol.ReturnType.FullName() == "System.Void")
     {
     var diagnostic = Diagnostic.Create(Rule02, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     }
     }
     private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
     {
     var methodSymbol = (IMethodSymbol)context.Symbol;
     if (!methodSymbol.IsAsync)
     {
     return;
     }
     if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     }
     変更前
     ✔変更後
     条件分岐を追加
     138
     

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139. private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
     {
     var methodSymbol = (IMethodSymbol)context.Symbol;
     if (!methodSymbol.IsAsync)
     {
     return;
     }
     if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     if (methodSymbol.ReturnType.FullName() == "System.Void")
     {
     var diagnostic = Diagnostic.Create(Rule02, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     }
     }
     private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
     {
     var methodSymbol = (IMethodSymbol)context.Symbol;
     if (!methodSymbol.IsAsync)
     {
     return;
     }
     if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     }
     変更前
     ✔変更後
     完全修飾型名がSystem.Voidかどうか判定
     139
     

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140. private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
     {
     var methodSymbol = (IMethodSymbol)context.Symbol;
     if (!methodSymbol.IsAsync)
     {
     return;
     }
     if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     if (methodSymbol.ReturnType.FullName() == "System.Void")
     {
     var diagnostic = Diagnostic.Create(Rule02, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     }
     }
     private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
     {
     var methodSymbol = (IMethodSymbol)context.Symbol;
     if (!methodSymbol.IsAsync)
     {
     return;
     }
     if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     }
     変更前
     private static readonly DiagnosticDescriptor Rule02 = new
     DiagnosticDescriptor(
     id: "BanAsyncTask0002",
     title: "Banned void in async Method",
     messageFormat: "Do not use '{0}' in async Method, Should use
     UniTaskVoid",
     category: "Naming",
     defaultSeverity: DiagnosticSeverity.Warning,
     isEnabledByDefault: true,
     description: "Type names should be all uppercase.");
     ✔変更後
     System.Voidの使用をレポートする
     ルールを追加
     140
     

     View Slide

141. private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
     {
     var methodSymbol = (IMethodSymbol)context.Symbol;
     if (!methodSymbol.IsAsync)
     {
     return;
     }
     if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     if (methodSymbol.ReturnType.FullName() == "System.Void")
     {
     var diagnostic = Diagnostic.Create(Rule02, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     }
     }
     private static void AnalyzeAsyncMethod(SymbolAnalysisContext context)
     {
     var methodSymbol = (IMethodSymbol)context.Symbol;
     if (!methodSymbol.IsAsync)
     {
     return;
     }
     if (methodSymbol.ReturnType.FullName() == "System.Threading.Tasks.Task")
     {
     var diagnostic = Diagnostic.Create(Rule01, methodSymbol.Locations[0], methodSymbol.ReturnType);
     context.ReportDiagnostic(diagnostic);
     return;
     }
     }
     変更前
     private static readonly DiagnosticDescriptor Rule02 = new
     DiagnosticDescriptor(
     id: "BanAsyncTask0002",
     title: "Banned void in async Method",
     messageFormat: "Do not use '{0}' in async Method, Should use
     UniTaskVoid",
     category: "Naming",
     defaultSeverity: DiagnosticSeverity.Warning,
     isEnabledByDefault: true,
     description: "Type names should be all uppercase.");
     ✔Passed
     ✔変更後
     141
     

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142. すべてのテストケースの実装が完了
     142
     

     View Slide

143. まとめ
     ● DiagnosticAnalyzer.Runを使ってアナライザーの実際の値を簡
     単に入手しよう
     ● DiagnosticsAssertでDiagnostic同士を比較しよう
     ● TestDataParserで簡単にテストの期待結果を作成しよう
     143
     

     View Slide

144. View Slide