FileSystemWatcher Analyzer

Author: inyutin-maxim

System.IO.Abstractions.Analyzers.Tests/Analyzers/DriveInfoAnalyzerTests.cs

@@ -18,7 +18,7 @@ public void Analyzer_is_not_triggered(string filename)
 		}
 
 		[Theory]
-		[InlineData("WithOutFileSystem.txt", 15, 4)]
+		[InlineData("WithOutFileSystem.txt", 15, 21)]
 		public void Analyzer_is_triggered(string filename, int diagnosticLine, int diagnosticColumn)
 		{
 			var source = ReadFile(filename);

System.IO.Abstractions.Analyzers.Tests/Analyzers/FileSystemWatcherAnalyzerTests.cs

@@ -0,0 +1,49 @@
+using System.Collections.Generic;
+using System.IO.Abstractions.Analyzers.Analyzers.FileSystemTypeAnalyzers;
+using Microsoft.CodeAnalysis;
+using Roslyn.Testing.Analyzer;
+using Roslyn.Testing.Model;
+using Xunit;
+
+namespace System.IO.Abstractions.Analyzers.Tests.Analyzers
+{
+	public class FileSystemWatcherAnalyzerTests : CSharpDiagnosticAnalyzerTest<FileSystemWatcherAnalyzer>
+	{
+		[Theory]
+		[InlineData("Valid.txt")]
+		public void Analyzer_is_not_triggered(string filename)
+		{
+			var source = ReadFile(filename);
+			VerifyNoDiagnosticTriggered(source);
+		}
+
+		[Theory]
+		[InlineData("WithOutFileSystem.txt", 15, 42)]
+		public void Analyzer_is_triggered(string filename, int diagnosticLine, int diagnosticColumn)
+		{
+			var source = ReadFile(filename);
+
+			var expectedDiagnostic = new DiagnosticResult
+			{
+				Id = FileSystemWatcherAnalyzer.DiagnosticId,
+				Message = FileSystemWatcherAnalyzer.MessageFormat,
+				Severity = DiagnosticSeverity.Warning,
+				Locations = new[] { new DiagnosticResultLocation("Test0.cs", diagnosticLine, diagnosticColumn) }
+			};
+
+			VerifyDiagnostic(source, expectedDiagnostic);
+		}
+
+		[Fact]
+		public void Empty_source_code_does_not_trigger_analyzer()
+		{
+			var source = string.Empty;
+			VerifyNoDiagnosticTriggered(source);
+		}
+
+		protected override IEnumerable<MetadataReference> GetAdditionalReferences() => new[]
+		{
+			MetadataReference.CreateFromFile(typeof(IFileSystem).Assembly.Location)
+		};
+	}
+}

System.IO.Abstractions.Analyzers.Tests/TestData/Analyzer/FileSystemWatcherAnalyzer/Valid.txt

@@ -0,0 +1,14 @@
+using System.IO.Abstractions;
+
+namespace SomeNameSpace
+{
+	public class Valid
+	{
+		private readonly IFileSystem _fileSystem;
+
+		public Valid(IFileSystem fileSystem)
+		{
+			_fileSystem = fileSystem;
+		}
+	}
+}

System.IO.Abstractions.Analyzers.Tests/TestData/Analyzer/FileSystemWatcherAnalyzer/WithOutFileSystem.txt

@@ -0,0 +1,18 @@
+using System.IO;
+
+namespace SomeNameSpace
+{
+	public class WithOutFileSystem
+	{
+		public WithOutFileSystem()
+		{
+		}
+
+		public void SomeMethod()
+		{
+			const string path = "C:\\temp.txt";
+
+			FileSystemWatcher fileSystemWatcher = new FileSystemWatcher();
+		}
+	}
+}

System.IO.Abstractions.Analyzers/Analyzers/FileSystemTypeAnalyzers/FileSystemWatcherAnalyzer.cs

@@ -0,0 +1,56 @@
+using System.Collections.Immutable;
+using JetBrains.Annotations;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
+using Microsoft.CodeAnalysis.Diagnostics;
+
+namespace System.IO.Abstractions.Analyzers.Analyzers.FileSystemTypeAnalyzers
+{
+    [DiagnosticAnalyzer(LanguageNames.CSharp)]
+    public class FileSystemWatcherAnalyzer: BaseFileSystemNodeObjectCreationAnalyzer
+	{
+		/// <summary>
+		/// Diagnostic Identifier
+		/// </summary>
+		[UsedImplicitly]
+		public const string DiagnosticId = "IO0009";
+
+		/// <summary>
+		/// Diagnostic Title
+		/// </summary>
+		private const string Title = "Invocation DriveInfo class shold be replaced with IFileSystem.DriveInfo";
+
+		/// <summary>
+		/// Diagnostic Message Format
+		/// </summary>
+		public const string MessageFormat = Title;
+
+		/// <summary>
+		/// Diagnostic Description
+		/// </summary>
+		private const string Description = Title;
+
+		/// <summary>
+		/// Правило
+		/// </summary>
+		private static readonly DiagnosticDescriptor Rule = new DiagnosticDescriptor(DiagnosticId,
+			Title,
+			MessageFormat,
+			Category,
+			DiagnosticSeverity.Warning,
+			true,
+			Description);
+
+		public override ImmutableArray<DiagnosticDescriptor> SupportedDiagnostics => ImmutableArray.Create(Rule);
+
+		protected override void Analyze(SyntaxNodeAnalysisContext context, ObjectCreationExpressionSyntax syntax)
+		{
+			context.ReportDiagnostic(Diagnostic.Create(Rule, syntax.GetLocation()));
+		}
+
+		protected override Type GetFileSystemType()
+		{
+			return typeof(FileSystemWatcher);
+		}
+	}
+}