Use Assert.Empty (#76862)

src/EditorFeatures/Test/Collections/Immutable/Maps/MapTests.cs

@@ -76,7 +76,7 @@ public void TestRemove()
         Assert.Equal(1, map.Count);
 
         map = map.Remove("5");
-        Assert.Equal(0, map.Count);
+        Assert.Empty(map);
     }
 
     [Fact]
@@ -116,7 +116,7 @@ public void TestPathology()
         Assert.Equal(1, map.Count);
 
         map = map.Remove("5");
-        Assert.Equal(0, map.Count);
+        Assert.Empty(map);
     }
 
     private class PathologicalComparer<T> : IEqualityComparer<T>

src/EditorFeatures/Test/Extensions/CollectionExtensionsTest.cs

@@ -21,15 +21,15 @@ public void PushReverse1()
         Assert.Equal(1, stack.Pop());
         Assert.Equal(2, stack.Pop());
         Assert.Equal(3, stack.Pop());
-        Assert.Equal(0, stack.Count);
+        Assert.Empty(stack);
     }
 
     [Fact]
     public void PushReverse2()
     {
         var stack = new Stack<int>();
         stack.PushReverse(Array.Empty<int>());
-        Assert.Equal(0, stack.Count);
+        Assert.Empty(stack);
     }
 
     [Fact]
@@ -41,6 +41,6 @@ public void PushReverse3()
         Assert.Equal(1, stack.Pop());
         Assert.Equal(2, stack.Pop());
         Assert.Equal(3, stack.Pop());
-        Assert.Equal(0, stack.Count);
+        Assert.Empty(stack);
     }
 }

src/EditorFeatures/Test/MetadataAsSource/AbstractMetadataAsSourceTests.TestContext.cs

@@ -104,7 +104,7 @@ public async Task<MetadataAsSourceFile> GenerateSourceAsync(
             // Get an ISymbol corresponding to the metadata name
             var compilation = await project.GetRequiredCompilationAsync(CancellationToken.None);
             var diagnostics = compilation.GetDiagnostics().ToArray();
-            Assert.Equal(0, diagnostics.Length);
+            Assert.Empty(diagnostics);
             var symbol = await ResolveSymbolAsync(symbolMetadataName, compilation);
             Contract.ThrowIfNull(symbol);
 
@@ -172,7 +172,7 @@ public void Dispose()
             {
                 compilation = await this.DefaultProject.GetRequiredCompilationAsync(CancellationToken.None);
                 var diagnostics = compilation.GetDiagnostics().ToArray();
-                Assert.Equal(0, diagnostics.Length);
+                Assert.Empty(diagnostics);
             }
 
             foreach (var reference in compilation.References)

src/EditorFeatures/Test2/CodeFixes/CodeFixServiceTests.vb

@@ -78,7 +78,7 @@ Namespace Microsoft.CodeAnalysis.Editor.Implementation.CodeFixes.UnitTests
                     (Await document.GetSyntaxRootAsync()).FullSpan,
                     CancellationToken.None)
 
-                Assert.Equal(0, fixes.Length)
+                Assert.Empty(fixes)
 
                 ' Verify available codefix with a global fixer + a project fixer
                 ' We will use this assembly as a project fixer provider.
@@ -102,7 +102,7 @@ Namespace Microsoft.CodeAnalysis.Editor.Implementation.CodeFixes.UnitTests
                     (Await document.GetSyntaxRootAsync()).FullSpan,
                     CancellationToken.None)
 
-                Assert.Equal(0, fixes.Length)
+                Assert.Empty(fixes)
             End Using
         End Function
 
@@ -150,7 +150,7 @@ Namespace Microsoft.CodeAnalysis.Editor.Implementation.CodeFixes.UnitTests
                     (Await document.GetSyntaxRootAsync()).FullSpan,
                     CancellationToken.None)
 
-                Assert.Equal(0, fixes.Length)
+                Assert.Empty(fixes)
 
                 ' Verify no codefix with a global fixer + a project fixer
                 ' We will use this assembly as a project fixer provider.
@@ -165,7 +165,7 @@ Namespace Microsoft.CodeAnalysis.Editor.Implementation.CodeFixes.UnitTests
                     (Await document.GetSyntaxRootAsync()).FullSpan,
                     CancellationToken.None)
 
-                Assert.Equal(0, fixes.Length)
+                Assert.Empty(fixes)
             End Using
         End Function
 

src/EditorFeatures/Test2/Diagnostics/DiagnosticProviderTests.vb

@@ -266,7 +266,7 @@ Namespace Microsoft.CodeAnalysis.Editor.Implementation.Diagnostics.UnitTests
                     includeSuppressedDiagnostics:=False, includeLocalDocumentDiagnostics:=True, includeNonLocalDocumentDiagnostics:=True, CancellationToken.None).Result
 
                 If diagnostics Is Nothing Then
-                    Assert.Equal(0, actualDiagnostics.Length)
+                    Assert.Empty(actualDiagnostics)
                 Else
                     Dim expectedDiagnostics = GetExpectedDiagnostics(workspace, diagnostics)
 

src/EditorFeatures/Test2/Diagnostics/DiagnosticServiceTests.vb

@@ -300,7 +300,7 @@ Namespace Microsoft.CodeAnalysis.Editor.Implementation.Diagnostics.UnitTests
                 project = project.WithCompilationOptions(newCompilationOptions)
                 document = project.Documents.Single()
                 diagnostics = Await GetDiagnosticsForSpanAsync(diagnosticService, document, span)
-                Assert.Equal(0, diagnostics.Length)
+                Assert.Empty(diagnostics)
 
                 Dim changeSeverityDiagOptions = New Dictionary(Of String, ReportDiagnostic)
                 changeSeverityDiagOptions.Add(workspaceDiagnosticAnalyzer.DiagDescriptor.Id, ReportDiagnostic.Error)
@@ -350,7 +350,7 @@ Namespace Microsoft.CodeAnalysis.Editor.Implementation.Diagnostics.UnitTests
 
                 Dim hostAnalyzers = solution.SolutionState.Analyzers
                 Dim workspaceDescriptors = hostAnalyzers.GetDiagnosticDescriptorsPerReference(diagnosticService.AnalyzerInfoCache)
-                Assert.Equal(0, workspaceDescriptors.Count)
+                Assert.Empty(workspaceDescriptors)
 
                 Dim descriptors1 = hostAnalyzers.GetDiagnosticDescriptorsPerReference(diagnosticService.AnalyzerInfoCache, p1)
                 Assert.Equal("XX0001", descriptors1.Single().Value.Single().Id)
@@ -494,14 +494,14 @@ Namespace Microsoft.CodeAnalysis.Editor.Implementation.Diagnostics.UnitTests
                 Dim descriptorsMap = solution.SolutionState.Analyzers.GetDiagnosticDescriptorsPerReference(diagnosticService.AnalyzerInfoCache, project)
                 Assert.Equal(1, descriptorsMap.Count)
                 Dim descriptors = descriptorsMap.First().Value
-                Assert.Equal(0, descriptors.Length)
+                Assert.Empty(descriptors)
 
                 Dim document = project.Documents.Single()
 
                 Dim incrementalAnalyzer = diagnosticService.CreateIncrementalAnalyzer(workspace)
                 Dim diagnostics = Await GetDiagnosticsForDocumentAsync(diagnosticService, document)
 
-                Assert.Equal(0, diagnostics.Length)
+                Assert.Empty(diagnostics)
             End Using
         End Function
 
@@ -534,7 +534,7 @@ Namespace Microsoft.CodeAnalysis.Editor.Implementation.Diagnostics.UnitTests
                 Dim incrementalAnalyzer = diagnosticService.CreateIncrementalAnalyzer(workspace)
                 Dim root = Await document.GetSyntaxRootAsync().ConfigureAwait(False)
                 Dim diagnostics = Await GetDiagnosticsForSpanAsync(diagnosticService, document, root.FullSpan)
-                Assert.Equal(0, diagnostics.Length)
+                Assert.Empty(diagnostics)
 
                 diagnostics = Await diagnosticService.GetDiagnosticsForIdsAsync(
                     project.Solution, projectId:=Nothing, documentId:=Nothing, diagnosticIds:=Nothing, shouldIncludeAnalyzer:=Nothing,
@@ -2096,7 +2096,7 @@ class MyClass
                 Dim document = project.Documents.Single()
                 Dim diagnostics = Await GetDiagnosticsForDocumentAsync(diagnosticService, document)
 
-                Assert.Equal(0, diagnostics.Length)
+                Assert.Empty(diagnostics)
             End Using
         End Function
 
@@ -2237,7 +2237,7 @@ class C
                 Dim diagnostics = Await diagnosticService.GetDiagnosticsForIdsAsync(
                     project.Solution, project.Id, documentId:=Nothing, diagnosticIds:=Nothing, shouldIncludeAnalyzer:=Nothing,
                     includeSuppressedDiagnostics:=False, includeLocalDocumentDiagnostics:=True, includeNonLocalDocumentDiagnostics:=True, CancellationToken.None)
-                Assert.Equal(0, diagnostics.Length)
+                Assert.Empty(diagnostics)
             End Using
         End Function
 

src/EditorFeatures/TestUtilities/Rename/RenamerTests.cs

@@ -99,7 +99,7 @@ protected async Task TestRenameDocument(
                 }
 
                 AssertEx.EqualOrDiff(endDocument.Text, (await updatedDocument.GetTextAsync()).ToString());
-                Assert.Equal(0, remainingErrors.Count);
+                Assert.Empty(remainingErrors);
             }
         }
 

src/EditorFeatures/VisualBasicTest/Recommendations/RecommendationTestHelpers.vb

@@ -147,7 +147,7 @@ Namespace Microsoft.CodeAnalysis.Editor.VisualBasic.UnitTests.Recommendations
                                       .OrderBy(Function(recommendation) recommendation) _
                                       .ToArray()
 
-            Assert.Equal(0, recommendedKeywords.Length)
+            Assert.Empty(recommendedKeywords)
         End Sub
 
         Private Function GetSourceCodeKind(testSource As XElement) As SourceCodeKind

src/ExpressionEvaluator/CSharp/Test/ExpressionCompiler/LocalFunctionTests.cs

@@ -41,8 +41,8 @@ int G()
                 string typeName;
                 var assembly = context.CompileGetLocals(locals, argumentsOnly: false, typeName: out typeName, testData: testData);
                 Assert.NotNull(assembly);
-                Assert.Equal(0, assembly.Count);
-                Assert.Equal(0, locals.Count);
+                Assert.Empty(assembly);
+                Assert.Empty(locals);
                 locals.Free();
             });
         }

src/ExpressionEvaluator/CSharp/Test/ExpressionCompiler/LocalsTests.cs

@@ -46,8 +46,8 @@ static void M()
                 string typeName;
                 var assembly = context.CompileGetLocals(locals, argumentsOnly: false, typeName: out typeName, testData: testData);
                 Assert.NotNull(assembly);
-                Assert.Equal(0, assembly.Count);
-                Assert.Equal(0, locals.Count);
+                Assert.Empty(assembly);
+                Assert.Empty(locals);
                 locals.Free();
             });
         }
@@ -2491,7 +2491,7 @@ static void M(A a, B b, C c)
                 Diagnostic(ErrorCode.ERR_NoTypeDef).WithArguments("A", "Comp1, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null").WithLocation(1, 1)
             ]);
 
-                Assert.Equal(0, locals.Count);
+                Assert.Empty(locals);
                 locals.Free();
             });
         }
@@ -2535,7 +2535,7 @@ static void M<T>(object o) where T : I
                 Diagnostic(ErrorCode.ERR_NoTypeDef).WithArguments("I", "Comp1, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null").WithLocation(1, 1)
             ]);
 
-                Assert.Equal(0, locals.Count);
+                Assert.Empty(locals);
                 locals.Free();
             });
         }
@@ -5116,7 +5116,7 @@ private static void GetLocals(RuntimeInstance runtime, string methodName, bool a
             Assert.NotNull(assembly);
             if (count == 0)
             {
-                Assert.Equal(0, assembly.Count);
+                Assert.Empty(assembly);
             }
             else
             {
@@ -5156,7 +5156,7 @@ private static void GetLocals(RuntimeInstance runtime, string methodName, Method
             Assert.NotNull(assembly);
             if (count == 0)
             {
-                Assert.Equal(0, assembly.Count);
+                Assert.Empty(assembly);
             }
             else
             {

src/ExpressionEvaluator/CSharp/Test/ExpressionCompiler/UsingDebugInfoTests.cs

@@ -405,11 +405,11 @@ public void BadPdb_ForwardChain()
 
             importStrings = CustomDebugInfoReader.GetCSharpGroupedImportStrings(methodToken2, 0, getMethodCustomDebugInfo, getMethodImportStrings, out externAliasStrings);
             Assert.Equal(importString, importStrings.Single().Single());
-            Assert.Equal(0, externAliasStrings.Length);
+            Assert.Empty(externAliasStrings);
 
             importStrings = CustomDebugInfoReader.GetCSharpGroupedImportStrings(methodToken2, 0, getMethodCustomDebugInfo, getMethodImportStrings, out externAliasStrings);
             Assert.Equal(importString, importStrings.Single().Single());
-            Assert.Equal(0, externAliasStrings.Length);
+            Assert.Empty(externAliasStrings);
         }
 
         [Fact]

src/ExpressionEvaluator/VisualBasic/Test/ExpressionCompiler/LocalsTests.vb

@@ -36,8 +36,8 @@ End Class"
                     Dim typeName As String = Nothing
                     Dim assembly = context.CompileGetLocals(locals, argumentsOnly:=False, typeName:=typeName, testData:=testData)
                     Assert.NotNull(assembly)
-                    Assert.Equal(0, assembly.Count)
-                    Assert.Equal(0, locals.Count)
+                    Assert.Empty(assembly)
+                    Assert.Empty(locals)
                     locals.Free()
                 End Sub)
         End Sub
@@ -1789,7 +1789,7 @@ End Class"
                         Diagnostic(ERRID.ERR_TypeRefResolutionError3, "a").WithArguments("A", "Test.dll").WithLocation(1, 1)
                     })
 
-                    Assert.Equal(0, locals.Count)
+                    Assert.Empty(locals)
                     locals.Free()
                 End Sub)
         End Sub
@@ -3373,7 +3373,7 @@ End Class"
 
             Assert.NotNull(assembly)
             If count = 0 Then
-                Assert.Equal(0, assembly.Count)
+                Assert.Empty(assembly)
             Else
                 Assert.InRange(assembly.Count, 0, Integer.MaxValue)
             End If
@@ -3408,7 +3408,7 @@ End Class"
 
             Assert.NotNull(assembly)
             If count = 0 Then
-                Assert.Equal(0, assembly.Count)
+                Assert.Empty(assembly)
             Else
                 Assert.InRange(assembly.Count, 0, Integer.MaxValue)
             End If

src/LanguageServer/ProtocolUnitTests/Diagnostics/PullDiagnosticTests.cs

@@ -1049,7 +1049,7 @@ class A {
 
         var results = await RunGetWorkspacePullDiagnosticsAsync(testLspServer, useVSDiagnostics: true, includeTaskListItems: false, category: PullDiagnosticCategories.Task);
 
-        Assert.Equal(0, results.Length);
+        Assert.Empty(results);
     }
 
     [Theory, CombinatorialData]
@@ -1115,7 +1115,7 @@ class A {
 
         var results = await RunGetWorkspacePullDiagnosticsAsync(testLspServer, useVSDiagnostics: true, includeTaskListItems: false, category: PullDiagnosticCategories.Task);
 
-        Assert.Equal(0, results.Length);
+        Assert.Empty(results);
     }
 
     [Theory, CombinatorialData]
@@ -2115,7 +2115,7 @@ public async Task TestWorkspaceDiagnosticsForClosedFilesSwitchFSAFromOffToOn(boo
 
         var results = await RunGetWorkspacePullDiagnosticsAsync(testLspServer, useVSDiagnostics);
 
-        Assert.Equal(0, results.Length);
+        Assert.Empty(results);
 
         var options = testLspServer.TestWorkspace.ExportProvider.GetExportedValue<IGlobalOptionService>();
         options.SetGlobalOption(SolutionCrawlerOptionsStorage.BackgroundAnalysisScopeOption, LanguageNames.CSharp, BackgroundAnalysisScope.FullSolution);

src/LanguageServer/ProtocolUnitTests/RelatedDocuments/RelatedDocumentsTests.cs

@@ -67,7 +67,7 @@ class Y
             project.Documents.First().GetURI(),
             useProgress: useProgress);
 
-        Assert.Equal(0, results.Length);
+        Assert.Empty(results);
     }
 
     [Theory, CombinatorialData]

src/Scripting/CoreTest.Desktop/GlobalAssemblyCacheTests.cs

@@ -72,17 +72,17 @@ public void GetAssemblyIdentities()
             }
 
             names = gac.GetAssemblyIdentities("x\u0002").ToArray();
-            Assert.Equal(0, names.Length);
+            Assert.Empty(names);
 
             names = gac.GetAssemblyIdentities("\0").ToArray();
-            Assert.Equal(0, names.Length);
+            Assert.Empty(names);
 
             names = gac.GetAssemblyIdentities("xxxx\0xxxxx").ToArray();
-            Assert.Equal(0, names.Length);
+            Assert.Empty(names);
 
             // fusion API CreateAssemblyEnum returns S_FALSE for this name
             names = gac.GetAssemblyIdentities("nonexistingassemblyname" + Guid.NewGuid().ToString()).ToArray();
-            Assert.Equal(0, names.Length);
+            Assert.Empty(names);
         }
 
         [Fact]

src/VisualStudio/CSharp/Test/DocumentOutline/DocumentOutlineTests.cs

@@ -146,7 +146,7 @@ public async Task TestSearchDocumentSymbolData()
 
             // No search results found
             searchedSymbols = DocumentOutlineViewModel.SearchDocumentSymbolData(model.DocumentSymbolData, "xyz", CancellationToken.None);
-            Assert.Equal(0, searchedSymbols.Length);
+            Assert.Empty(searchedSymbols);
         }
 
         [WpfFact, WorkItem("https://github.com/dotnet/roslyn/issues/66012")]

src/Workspaces/CSharpTest/CodeGeneration/SyntaxGeneratorTests.cs

@@ -1966,15 +1966,15 @@ public void TestAddAttributesToAccessors()
         private void CheckAddRemoveAttribute(SyntaxNode declaration)
         {
             var initialAttributes = Generator.GetAttributes(declaration);
-            Assert.Equal(0, initialAttributes.Count);
+            Assert.Empty(initialAttributes);
 
             var withAttribute = Generator.AddAttributes(declaration, Generator.Attribute("a"));
             var attrsAdded = Generator.GetAttributes(withAttribute);
             Assert.Equal(1, attrsAdded.Count);
 
             var withoutAttribute = Generator.RemoveNode(withAttribute, attrsAdded[0]);
             var attrsRemoved = Generator.GetAttributes(withoutAttribute);
-            Assert.Equal(0, attrsRemoved.Count);
+            Assert.Empty(attrsRemoved);
         }
 
         [Fact]
@@ -3662,7 +3662,7 @@ public void TestGetBaseAndInterfaceTypes()
 
             var baseListN = Generator.GetBaseAndInterfaceTypes(classN);
             Assert.NotNull(baseListN);
-            Assert.Equal(0, baseListN.Count);
+            Assert.Empty(baseListN);
         }
 
         [Fact]