use collection expression instead of Array.Empty

src/Microsoft.TemplateEngine.Abstractions/Installer/CheckUpdateResult.cs

@@ -16,7 +16,7 @@ private CheckUpdateResult(string? latestVersion, bool isLatest, IManagedTemplate
             TemplatePackage = templatePackage;
             LatestVersion = latestVersion;
             IsLatestVersion = isLatest;
-            Vulnerabilities = Array.Empty<VulnerabilityInfo>();
+            Vulnerabilities = [];
         }
 
         private CheckUpdateResult(

src/Microsoft.TemplateEngine.Abstractions/Parameters/ParameterSetData.cs

@@ -61,7 +61,7 @@ public ParameterSetData(ITemplateInfo templateInfo, IReadOnlyDictionary<string,
     /// Empty instance.
     /// </summary>
     public static IParameterSetData Empty =>
-        new ParameterSetData(new ParameterDefinitionSet((IReadOnlyDictionary<string, ITemplateParameter>?)null), System.Array.Empty<ParameterData>());
+        new ParameterSetData(new ParameterDefinitionSet((IReadOnlyDictionary<string, ITemplateParameter>?)null), []);
 
     /// <inheritdoc/>
     public IParameterDefinitionSet ParametersDefinition { get; }

src/Microsoft.TemplateEngine.Core/Expressions/Cpp/CppStyleEvaluatorDefinition.cs

@@ -16,7 +16,7 @@ public static class CppStyleEvaluatorDefinition
     {
         private const int ReservedTokenCount = 24;
         private const int ReservedTokenMaxIndex = ReservedTokenCount - 1;
-        private static readonly IOperationProvider[] NoOperationProviders = Array.Empty<IOperationProvider>();
+        private static readonly IOperationProvider[] NoOperationProviders = [];
         private static readonly char[] SupportedQuotes = { '"', '\'' };
 
         public static bool EvaluateFromString(ILogger logger, string text, IVariableCollection variables)

src/Microsoft.TemplateEngine.Core/Expressions/Shared/SharedEvaluatorDefinition.cs

@@ -18,7 +18,7 @@ public abstract class SharedEvaluatorDefinition<TSelf, TTokens>
         private static readonly IOperatorMap<Operators, TTokens> Map = Instance.GenerateMap();
         private static readonly bool DereferenceInLiteralsSetting = Instance.DereferenceInLiterals;
         private static readonly string NullToken = Instance.NullTokenValue;
-        private static readonly IOperationProvider[] NoOperationProviders = Array.Empty<IOperationProvider>();
+        private static readonly IOperationProvider[] NoOperationProviders = [];
 
         protected abstract string NullTokenValue { get; }
 

src/Microsoft.TemplateEngine.Core/FileChange.cs

@@ -12,7 +12,7 @@ public FileChange(string sourceRelativePath, string targetRelativePath, ChangeKi
             SourceRelativePath = sourceRelativePath;
             TargetRelativePath = targetRelativePath;
             ChangeKind = changeKind;
-            Contents = contents ?? Array.Empty<byte>();
+            Contents = contents ?? [];
         }
 
         public string SourceRelativePath { get; }

src/Microsoft.TemplateEngine.Core/Operations/ConditionalTokens.cs

@@ -9,14 +9,14 @@ public class ConditionalTokens
     {
         public ConditionalTokens()
         {
-            IfTokens = Array.Empty<ITokenConfig>();
-            ElseTokens = Array.Empty<ITokenConfig>();
-            ElseIfTokens = Array.Empty<ITokenConfig>();
-            EndIfTokens = Array.Empty<ITokenConfig>();
-            ActionableIfTokens = Array.Empty<ITokenConfig>();
-            ActionableElseTokens = Array.Empty<ITokenConfig>();
-            ActionableElseIfTokens = Array.Empty<ITokenConfig>();
-            ActionableOperations = Array.Empty<string>();
+            IfTokens = [];
+            ElseTokens = [];
+            ElseIfTokens = [];
+            EndIfTokens = [];
+            ActionableIfTokens = [];
+            ActionableElseTokens = [];
+            ActionableElseIfTokens = [];
+            ActionableOperations = [];
         }
 
         public IReadOnlyList<ITokenConfig> IfTokens { get; set; }

src/Microsoft.TemplateEngine.Core/Operations/InlineMarkupConditional.cs

@@ -106,7 +106,7 @@ public int HandleMatch(IProcessorState processor, int bufferLength, ref int curr
                 ScanToCloseCondition(processor, conditionBytes, ref bufferLength, ref currentBufferPosition);
                 byte[] condition = conditionBytes.ToArray();
                 EngineConfig adjustedConfig = new EngineConfig(processor.Config.Logger, processor.Config.Whitespaces, processor.Config.LineEndings, processor.Config.Variables, _definition.VariableFormat);
-                IProcessorState localState = new ProcessorState(new MemoryStream(condition), new MemoryStream(), conditionBytes.Count, int.MaxValue, adjustedConfig, Array.Empty<IOperationProvider>());
+                IProcessorState localState = new ProcessorState(new MemoryStream(condition), new MemoryStream(), conditionBytes.Count, int.MaxValue, adjustedConfig, []);
                 int pos = 0;
                 int len = conditionBytes.Count;
 

src/Microsoft.TemplateEngine.Core/TokenConfig.cs

@@ -44,9 +44,9 @@ public TokenConfig OnlyIfBefore(string? suffix)
 
         public IToken ToToken(Encoding encoding)
         {
-            byte[] pre = string.IsNullOrEmpty(After) ? Array.Empty<byte>() : encoding.GetBytes(After);
-            byte[] post = string.IsNullOrEmpty(Before) ? Array.Empty<byte>() : encoding.GetBytes(Before);
-            byte[] core = string.IsNullOrEmpty(Value) ? Array.Empty<byte>() : encoding.GetBytes(Value);
+            byte[] pre = string.IsNullOrEmpty(After) ? [] : encoding.GetBytes(After);
+            byte[] post = string.IsNullOrEmpty(Before) ? [] : encoding.GetBytes(Before);
+            byte[] core = string.IsNullOrEmpty(Value) ? [] : encoding.GetBytes(Value);
 
             byte[] buffer = new byte[pre.Length + core.Length + post.Length];
 

src/Microsoft.TemplateEngine.Core/Util/EncodingUtil.cs

@@ -16,7 +16,7 @@ public static Encoding Detect(byte[] buffer, int currentBufferLength, out byte[]
             if (currentBufferLength == 0)
             {
                 //File is zero length - pick something
-                bom = System.Array.Empty<byte>();
+                bom = [];
                 return Encoding.UTF8;
             }
 
@@ -65,7 +65,7 @@ public static Encoding Detect(byte[] buffer, int currentBufferLength, out byte[]
             }
 
             //Fallback to UTF-8
-            bom = System.Array.Empty<byte>();
+            bom = [];
             return Encoding.UTF8;
         }
     }

src/Microsoft.TemplateEngine.Core/VariableCollection.cs

@@ -9,7 +9,7 @@ namespace Microsoft.TemplateEngine.Core
 {
     public class VariableCollection : IVariableCollection, IMonitoredVariableCollection
     {
-        private static readonly IEnumerable<string> NoKeys = Array.Empty<string>();
+        private static readonly IEnumerable<string> NoKeys = [];
         private readonly IDictionary<string, object> _values;
         private IVariableCollection? _parent;
 

src/Microsoft.TemplateEngine.Edge/BuiltInManagedProvider/GlobalSettings.cs

@@ -72,7 +72,7 @@ public async Task<IReadOnlyList<TemplatePackageData>> GetInstalledTemplatePackag
 
             if (!_environmentSettings.Host.FileSystem.FileExists(_globalSettingsFile))
             {
-                return Array.Empty<TemplatePackageData>();
+                return [];
             }
 
             for (int i = 0; i < FileReadWriteRetries; i++)

src/Microsoft.TemplateEngine.Edge/BuiltInManagedProvider/GlobalSettingsTemplatePackageProvider.cs

@@ -137,15 +137,15 @@ public async Task<IReadOnlyList<InstallResult>> InstallAsync(IEnumerable<Install
                         installRequest,
                         InstallerErrorCode.UnsupportedRequest,
                         string.Format(LocalizableStrings.GlobalSettingsTemplatePackageProvider_InstallResult_Error_PackageCannotBeInstalled, installRequest.PackageIdentifier),
-                        Array.Empty<VulnerabilityInfo>());
+                        []);
                 }
                 if (installersThatCanInstall.Count > 1)
                 {
                     return InstallResult.CreateFailure(
                         installRequest,
                         InstallerErrorCode.UnsupportedRequest,
                         string.Format(LocalizableStrings.GlobalSettingsTemplatePackageProvider_InstallResult_Error_MultipleInstallersCanBeUsed, installRequest.PackageIdentifier),
-                        Array.Empty<VulnerabilityInfo>());
+                        []);
                 }
 
                 IInstaller installer = installersThatCanInstall[0];
@@ -220,7 +220,7 @@ private async Task<UpdateResult> UpdateAsync(List<TemplatePackageData> packages,
             (InstallerErrorCode result, string message) = await EnsureInstallPrerequisites(packages, updateRequest.TemplatePackage.Identifier, updateRequest.Version, updateRequest.TemplatePackage.Installer, cancellationToken, update: true).ConfigureAwait(false);
             if (result != InstallerErrorCode.Success)
             {
-                return UpdateResult.CreateFailure(updateRequest, result, message, Array.Empty<VulnerabilityInfo>());
+                return UpdateResult.CreateFailure(updateRequest, result, message, []);
             }
 
             UpdateResult updateResult = await updateRequest.TemplatePackage.Installer.UpdateAsync(updateRequest, provider: this, cancellationToken).ConfigureAwait(false);
@@ -302,7 +302,7 @@ private async Task<InstallResult> InstallAsync(List<TemplatePackageData> package
                 forceUpdate: installRequest.Force).ConfigureAwait(false);
             if (result != InstallerErrorCode.Success)
             {
-                return InstallResult.CreateFailure(installRequest, result, message, Array.Empty<VulnerabilityInfo>());
+                return InstallResult.CreateFailure(installRequest, result, message, []);
             }
 
             InstallResult installResult = await installer.InstallAsync(installRequest, this, cancellationToken).ConfigureAwait(false);

src/Microsoft.TemplateEngine.Edge/DefaultTemplateEngineHost.cs

@@ -11,7 +11,7 @@ namespace Microsoft.TemplateEngine.Edge
 {
     public class DefaultTemplateEngineHost : ITemplateEngineHost
     {
-        private static readonly IReadOnlyList<(Type, IIdentifiedComponent)> NoComponents = Array.Empty<(Type, IIdentifiedComponent)>();
+        private static readonly IReadOnlyList<(Type, IIdentifiedComponent)> NoComponents = [];
         private readonly IReadOnlyDictionary<string, string> _hostDefaults;
         private readonly IReadOnlyList<(Type InterfaceType, IIdentifiedComponent Instance)> _hostBuiltInComponents;
         private readonly ILoggerFactory _loggerFactory;

src/Microsoft.TemplateEngine.Edge/FilterableTemplateInfo.cs

@@ -74,9 +74,9 @@ private FilterableTemplateInfo(ITemplateInfo source)
 
         public IReadOnlyDictionary<string, string> TagsCollection { get; private set; }
 
-        IReadOnlyList<Guid> ITemplateMetadata.PostActions => _source?.PostActions ?? Array.Empty<Guid>();
+        IReadOnlyList<Guid> ITemplateMetadata.PostActions => _source?.PostActions ?? [];
 
-        IReadOnlyList<TemplateConstraintInfo> ITemplateMetadata.Constraints => _source?.Constraints ?? Array.Empty<TemplateConstraintInfo>();
+        IReadOnlyList<TemplateConstraintInfo> ITemplateMetadata.Constraints => _source?.Constraints ?? [];
 
         public static FilterableTemplateInfo FromITemplateInfo(ITemplateInfo source)
         {

src/Microsoft.TemplateEngine.Edge/Installers/Folder/FolderInstaller.cs

@@ -56,7 +56,7 @@ public Task<InstallResult> InstallAsync(InstallRequest installRequest, IManagedT
                 return Task.FromResult(InstallResult.CreateSuccess(
                     installRequest,
                     new FolderManagedTemplatePackage(_settings, this, provider, installRequest.PackageIdentifier, DateTime.UtcNow),
-                    Array.Empty<VulnerabilityInfo>()));
+                    []));
             }
             else
             {
@@ -65,7 +65,7 @@ public Task<InstallResult> InstallAsync(InstallRequest installRequest, IManagedT
                     installRequest,
                     InstallerErrorCode.PackageNotFound,
                     string.Format(LocalizableStrings.FolderInstaller_InstallResult_Error_FolderDoesNotExist, installRequest.PackageIdentifier),
-                    Array.Empty<VulnerabilityInfo>()));
+                    []));
             }
         }
 
@@ -98,7 +98,7 @@ public Task<UpdateResult> UpdateAsync(UpdateRequest updateRequest, IManagedTempl
             return Task.FromResult(UpdateResult.CreateSuccess(
                 updateRequest,
                 new FolderManagedTemplatePackage(_settings, this, provider, updateRequest.TemplatePackage.Identifier, DateTime.UtcNow),
-                Array.Empty<VulnerabilityInfo>()));
+                []));
         }
     }
 }

src/Microsoft.TemplateEngine.Edge/Installers/NuGet/NuGetInstaller.cs

@@ -143,7 +143,7 @@ public async Task<IReadOnlyList<CheckUpdateResult>> GetLatestVersionAsync(
                                 package,
                                 InstallerErrorCode.PackageNotFound,
                                 string.Format(LocalizableStrings.NuGetInstaller_Error_FailedToReadPackage, e.PackageIdentifier, string.Join(", ", e.SourcesList)),
-                                Array.Empty<VulnerabilityInfo>());
+                                []);
                         }
                         catch (InvalidNuGetSourceException e)
                         {
@@ -155,15 +155,15 @@ public async Task<IReadOnlyList<CheckUpdateResult>> GetLatestVersionAsync(
                                 package,
                                 InstallerErrorCode.InvalidSource,
                                 message,
-                                Array.Empty<VulnerabilityInfo>());
+                                []);
                         }
                         catch (OperationCanceledException)
                         {
                             return CheckUpdateResult.CreateFailure(
                                 package,
                                 InstallerErrorCode.GenericError,
                                 LocalizableStrings.NuGetInstaller_InstallResult_Error_OperationCancelled,
-                                Array.Empty<VulnerabilityInfo>());
+                                []);
                         }
                         catch (VulnerablePackageException e)
                         {
@@ -180,7 +180,7 @@ public async Task<IReadOnlyList<CheckUpdateResult>> GetLatestVersionAsync(
                                 package,
                                 InstallerErrorCode.GenericError,
                                 string.Format(LocalizableStrings.NuGetInstaller_InstallResult_Error_UpdateCheckGeneric, package.DisplayName, e.Message),
-                                Array.Empty<VulnerabilityInfo>());
+                                []);
                         }
                     }
                     else
@@ -189,7 +189,7 @@ public async Task<IReadOnlyList<CheckUpdateResult>> GetLatestVersionAsync(
                             package,
                             InstallerErrorCode.UnsupportedRequest,
                             string.Format(LocalizableStrings.NuGetInstaller_InstallResult_Error_PackageNotSupported, package.DisplayName, Factory.Name),
-                            Array.Empty<VulnerabilityInfo>());
+                            []);
                     }
                 })).ConfigureAwait(false);
         }
@@ -205,7 +205,7 @@ public async Task<InstallResult> InstallAsync(InstallRequest installRequest, IMa
                     installRequest,
                     InstallerErrorCode.UnsupportedRequest,
                     string.Format(LocalizableStrings.NuGetInstaller_InstallResult_Error_PackageNotSupported, installRequest.DisplayName, Factory.Name),
-                    Array.Empty<VulnerabilityInfo>());
+                    []);
             }
 
             try
@@ -218,7 +218,7 @@ public async Task<InstallResult> InstallAsync(InstallRequest installRequest, IMa
                 }
                 else
                 {
-                    string[] additionalNuGetSources = Array.Empty<string>();
+                    string[] additionalNuGetSources = [];
                     if (installRequest.Details != null && installRequest.Details.TryGetValue(InstallerConstants.NuGetSourcesKey, out string nugetSources))
                     {
                         additionalNuGetSources = nugetSources.Split(InstallerConstants.NuGetSourcesSeparator);
@@ -261,15 +261,15 @@ public async Task<InstallResult> InstallAsync(InstallRequest installRequest, IMa
                     installRequest,
                     InstallerErrorCode.DownloadFailed,
                     string.Format(LocalizableStrings.NuGetInstaller_InstallResult_Error_DownloadFailed, installRequest.DisplayName, packageLocation),
-                    Array.Empty<VulnerabilityInfo>());
+                    []);
             }
             catch (PackageNotFoundException e)
             {
                 return InstallResult.CreateFailure(
                     installRequest,
                     InstallerErrorCode.PackageNotFound,
                     string.Format(LocalizableStrings.NuGetInstaller_Error_FailedToReadPackage, e.PackageIdentifier, string.Join(", ", e.SourcesList)),
-                    Array.Empty<VulnerabilityInfo>());
+                    []);
             }
             catch (InvalidNuGetSourceException e)
             {
@@ -281,15 +281,15 @@ public async Task<InstallResult> InstallAsync(InstallRequest installRequest, IMa
                         installRequest,
                         InstallerErrorCode.InvalidSource,
                         message,
-                        Array.Empty<VulnerabilityInfo>());
+                        []);
             }
             catch (InvalidNuGetPackageException e)
             {
                 return InstallResult.CreateFailure(
                     installRequest,
                     InstallerErrorCode.InvalidPackage,
                     string.Format(LocalizableStrings.NuGetInstaller_InstallResult_Error_InvalidPackage, e.PackageLocation),
-                    Array.Empty<VulnerabilityInfo>());
+                    []);
             }
             catch (VulnerablePackageException e)
             {
@@ -305,7 +305,7 @@ public async Task<InstallResult> InstallAsync(InstallRequest installRequest, IMa
                     installRequest,
                     InstallerErrorCode.GenericError,
                     LocalizableStrings.NuGetInstaller_InstallResult_Error_OperationCancelled,
-                    Array.Empty<VulnerabilityInfo>());
+                    []);
             }
             catch (Exception e)
             {
@@ -314,7 +314,7 @@ public async Task<InstallResult> InstallAsync(InstallRequest installRequest, IMa
                     installRequest,
                     InstallerErrorCode.GenericError,
                     string.Format(LocalizableStrings.NuGetInstaller_InstallResult_Error_InstallGeneric, installRequest.DisplayName, e.Message),
-                    Array.Empty<VulnerabilityInfo>());
+                    []);
             }
         }
 
@@ -374,7 +374,7 @@ public async Task<UpdateResult> UpdateAsync(UpdateRequest updateRequest, IManage
                 {
                     throw new InvalidOperationException($"{nameof(uninstallResult.ErrorMessage)} cannot be null when {nameof(uninstallResult.Success)} is 'true'");
                 }
-                return UpdateResult.CreateFailure(updateRequest, uninstallResult.Error, uninstallResult.ErrorMessage, Array.Empty<VulnerabilityInfo>());
+                return UpdateResult.CreateFailure(updateRequest, uninstallResult.Error, uninstallResult.ErrorMessage, []);
             }
 
             Dictionary<string, string> installationDetails = new Dictionary<string, string>();
@@ -443,7 +443,7 @@ private NuGetPackageInfo ReadPackageInformation(string packageLocation)
                 null,
                 nuspec.GetId(),
                 nuspec.GetVersion().ToNormalizedString(),
-                Array.Empty<VulnerabilityInfo>());
+                []);
         }
     }
 }