Fixed nullability warnings in methods signatures

samples/BenchmarkDotNet.Samples/IntroOrderManual.cs

@@ -22,7 +22,7 @@ private class Config : ManualConfig
             private class FastestToSlowestOrderer : IOrderer
             {
                 public IEnumerable<BenchmarkCase> GetExecutionOrder(ImmutableArray<BenchmarkCase> benchmarksCase,
-                    IEnumerable<BenchmarkLogicalGroupRule> order = null) =>
+                    IEnumerable<BenchmarkLogicalGroupRule>? order = null) =>
                     from benchmark in benchmarksCase
                     orderby benchmark.Parameters["X"] descending,
                         benchmark.Descriptor.WorkloadMethodDisplayInfo
@@ -39,7 +39,7 @@ public string GetLogicalGroupKey(ImmutableArray<BenchmarkCase> allBenchmarksCase
                     benchmarkCase.Job.DisplayInfo + "_" + benchmarkCase.Parameters.DisplayInfo;
 
                 public IEnumerable<IGrouping<string, BenchmarkCase>> GetLogicalGroupOrder(IEnumerable<IGrouping<string, BenchmarkCase>> logicalGroups,
-                    IEnumerable<BenchmarkLogicalGroupRule> order = null) =>
+                    IEnumerable<BenchmarkLogicalGroupRule>? order = null) =>
                     logicalGroups.OrderBy(it => it.Key);
 
                 public bool SeparateLogicalGroups => true;

src/BenchmarkDotNet.Diagnostics.Windows/Configs/InliningDiagnoserAttribute.cs

@@ -13,7 +13,7 @@ public InliningDiagnoserAttribute(bool logFailuresOnly = true, bool filterByName
             Config = ManualConfig.CreateEmpty().AddDiagnoser(new InliningDiagnoser(logFailuresOnly, filterByNamespace));
         }
 
-        public InliningDiagnoserAttribute(bool logFailuresOnly = true, string[] allowedNamespaces = null)
+        public InliningDiagnoserAttribute(bool logFailuresOnly = true, string[]? allowedNamespaces = null)
         {
             Config = ManualConfig.CreateEmpty().AddDiagnoser(new InliningDiagnoser(logFailuresOnly, allowedNamespaces));
         }

src/BenchmarkDotNet.Diagnostics.Windows/EtwDiagnoser.cs

@@ -97,7 +97,7 @@ private void Clear()
 
         private void OnProcessExit(object sender, EventArgs e) => Session?.Dispose();
 
-        private static string GetSessionName(string prefix, BenchmarkCase benchmarkCase, ParameterInstances parameters = null)
+        private static string GetSessionName(string prefix, BenchmarkCase benchmarkCase, ParameterInstances? parameters = null)
         {
             if (parameters != null && parameters.Items.Count > 0)
                 return $"{prefix}-{benchmarkCase.FolderInfo}-{parameters.FolderInfo}";

src/BenchmarkDotNet.Diagnostics.Windows/EtwProfilerConfig.cs

@@ -41,8 +41,8 @@ public EtwProfilerConfig(
             float cpuSampleIntervalInMilliseconds = 1.0f,
             KernelTraceEventParser.Keywords kernelKeywords = KernelTraceEventParser.Keywords.ImageLoad | KernelTraceEventParser.Keywords.Profile,
             KernelTraceEventParser.Keywords kernelStackKeywords = KernelTraceEventParser.Keywords.Profile,
-            IReadOnlyDictionary<HardwareCounter, Func<ProfileSourceInfo, int>> intervalSelectors = null,
-            IReadOnlyCollection<(Guid providerGuid, TraceEventLevel providerLevel, ulong keywords, TraceEventProviderOptions options)> providers = null,
+            IReadOnlyDictionary<HardwareCounter, Func<ProfileSourceInfo, int>>? intervalSelectors = null,
+            IReadOnlyCollection<(Guid providerGuid, TraceEventLevel providerLevel, ulong keywords, TraceEventProviderOptions options)>? providers = null,
             bool createHeapSession = false)
         {
             CreateHeapSession = createHeapSession;

src/BenchmarkDotNet.Diagnostics.Windows/InliningDiagnoser.cs

@@ -35,7 +35,7 @@ public InliningDiagnoser(bool logFailuresOnly = true, bool filterByNamespace = t
         /// </summary>
         /// <param name="logFailuresOnly">only the methods that failed to get inlined. True by default.</param>
         /// <param name="allowedNamespaces">list of namespaces from which inlining message should be print.</param>
-        public InliningDiagnoser(bool logFailuresOnly = true, string[] allowedNamespaces = null)
+        public InliningDiagnoser(bool logFailuresOnly = true, string[]? allowedNamespaces = null)
         {
             this.logFailuresOnly = logFailuresOnly;
             this.allowedNamespaces = allowedNamespaces;

src/BenchmarkDotNet/Code/EnumParam.cs

@@ -24,7 +24,7 @@ private EnumParam(object value, Type type)
         public string ToSourceCode() =>
             $"({type.GetCorrectCSharpTypeName()})({ToInvariantCultureString()})";
 
-        internal static IParam FromObject(object value, Type type = null)
+        internal static IParam FromObject(object value, Type? type = null)
         {
             type = type ?? value.GetType();
             if (!type.IsEnum)

src/BenchmarkDotNet/Columns/StatisticColumn.cs

@@ -107,7 +107,7 @@ private enum Priority
         private readonly IStatisticColumn parentColumn;
 
         private StatisticColumn(string columnName, string legend, Func<Statistics, double> calc, Priority priority, UnitType type = UnitType.Time,
-            IStatisticColumn parentColumn = null)
+            IStatisticColumn? parentColumn = null)
         {
             this.calc = calc;
             this.priority = priority;

src/BenchmarkDotNet/ConsoleArguments/ConfigParser.cs

@@ -72,7 +72,7 @@ public static class ConfigParser
                 { "fullxml", new[] { XmlExporter.Full } }
             };
 
-        public static (bool isSuccess, IConfig config, CommandLineOptions options) Parse(string[] args, ILogger logger, IConfig globalConfig = null)
+        public static (bool isSuccess, IConfig config, CommandLineOptions options) Parse(string[] args, ILogger logger, IConfig? globalConfig = null)
         {
             (bool isSuccess, IConfig config, CommandLineOptions options) result = default;
 

src/BenchmarkDotNet/Diagnosers/EventPipeProfiler.cs

@@ -40,7 +40,7 @@ public EventPipeProfiler() :this(profile: EventPipeProfile.CpuSampling, performE
         /// <param name="profile">A named pre-defined set of provider configurations that allows common tracing scenarios to be specified succinctly.</param>
         /// <param name="providers">A list of EventPipe providers to be enabled.</param>
         /// <param name="performExtraBenchmarksRun">if set to true, benchmarks will be executed one more time with the profiler attached. If set to false, there will be no extra run but the results will contain overhead. True by default.</param>
-        public EventPipeProfiler(EventPipeProfile profile = EventPipeProfile.CpuSampling, IReadOnlyCollection<EventPipeProvider> providers = null, bool performExtraBenchmarksRun = true)
+        public EventPipeProfiler(EventPipeProfile profile = EventPipeProfile.CpuSampling, IReadOnlyCollection<EventPipeProvider>? providers = null, bool performExtraBenchmarksRun = true)
         {
             this.performExtraBenchmarksRun = performExtraBenchmarksRun;
             eventPipeProviders = MapToProviders(profile, providers);

src/BenchmarkDotNet/Disassemblers/DisassemblyDiagnoserConfig.cs

@@ -22,8 +22,8 @@ public class DisassemblyDiagnoserConfig
         public DisassemblyDiagnoserConfig(
             int maxDepth = 1,
             DisassemblySyntax syntax = DisassemblySyntax.Masm,
-            string[] filters = null,
-            FormatterOptions formatterOptions = null,
+            string[]? filters = null,
+            FormatterOptions? formatterOptions = null,
             bool printSource = false,
             bool printInstructionAddresses = false,
             bool exportGithubMarkdown = true,

src/BenchmarkDotNet/Environments/Runtimes/ClrRuntime.cs

@@ -17,7 +17,7 @@ public class ClrRuntime : Runtime, IEquatable<ClrRuntime>
 
         public string Version { get; }
 
-        private ClrRuntime(RuntimeMoniker runtimeMoniker, string msBuildMoniker, string displayName, string version = null)
+        private ClrRuntime(RuntimeMoniker runtimeMoniker, string msBuildMoniker, string displayName, string? version = null)
             : base(runtimeMoniker, msBuildMoniker, displayName)
         {
             Version = version;

src/BenchmarkDotNet/Environments/Runtimes/WasmRuntime.cs

@@ -28,7 +28,7 @@ public class WasmRuntime : Runtime, IEquatable<WasmRuntime>
         /// <param name="aot">Specifies whether AOT or Interpreter (default) project should be generated.</param>
         /// <param name="wasmDataDir">Specifies a wasm data directory surfaced as $(WasmDataDir) for the project</param>
         /// <param name="moniker">Runtime moniker</param>
-        public WasmRuntime(string msBuildMoniker = "net5.0", string displayName = "Wasm", string javaScriptEngine = "v8", string javaScriptEngineArguments = "--expose_wasm", bool aot = false, string wasmDataDir = null, RuntimeMoniker moniker = RuntimeMoniker.Wasm) : base(moniker, msBuildMoniker, displayName)
+        public WasmRuntime(string msBuildMoniker = "net5.0", string displayName = "Wasm", string javaScriptEngine = "v8", string javaScriptEngineArguments = "--expose_wasm", bool aot = false, string? wasmDataDir = null, RuntimeMoniker moniker = RuntimeMoniker.Wasm) : base(moniker, msBuildMoniker, displayName)
         {
             if (!string.IsNullOrEmpty(javaScriptEngine) && javaScriptEngine != "v8" && !File.Exists(javaScriptEngine))
                 throw new FileNotFoundException($"Provided {nameof(javaScriptEngine)} file: \"{javaScriptEngine}\" doest NOT exist");

src/BenchmarkDotNet/Exporters/Csv/CsvMeasurementsExporter.cs

@@ -20,7 +20,7 @@ public class CsvMeasurementsExporter : ExporterBase
         private static readonly Lazy<MeasurementColumn[]> Columns = new Lazy<MeasurementColumn[]>(BuildColumns);
 
         private readonly CsvSeparator separator;
-        public CsvMeasurementsExporter(CsvSeparator separator, SummaryStyle style = null)
+        public CsvMeasurementsExporter(CsvSeparator separator, SummaryStyle? style = null)
         {
             this.separator = separator;
             Style = style ?? SummaryStyle.Default;

src/BenchmarkDotNet/Helpers/ProcessHelper.cs

@@ -12,7 +12,7 @@ internal static class ProcessHelper
         /// Run external process and return the console output.
         /// In the case of any exception, null will be returned.
         /// </summary>
-        internal static string? RunAndReadOutput(string fileName, string arguments = "", ILogger logger = null)
+        internal static string? RunAndReadOutput(string fileName, string arguments = "", ILogger? logger = null)
         {
             var processStartInfo = new ProcessStartInfo
             {
@@ -42,7 +42,7 @@ internal static class ProcessHelper
         }
 
         internal static (int exitCode, ImmutableArray<string> output) RunAndReadOutputLineByLine(string fileName, string arguments = "", string workingDirectory = "",
-            Dictionary<string, string> environmentVariables = null, bool includeErrors = false, ILogger logger = null)
+            Dictionary<string, string>? environmentVariables = null, bool includeErrors = false, ILogger? logger = null)
         {
             var processStartInfo = new ProcessStartInfo
             {

src/BenchmarkDotNet/Jobs/JobExtensions.cs

@@ -339,7 +339,7 @@ public static Job WithEnvironmentVariable(this Job job, string key, string value
         /// <param name="source">(optional)Indicate the URI of the NuGet package source to use during the restore operation.</param>
         /// <param name="prerelease">(optional)Allows prerelease packages to be installed.</param>
         /// <returns></returns>
-        public static Job WithNuGet(this Job job, string packageName, string packageVersion = null, Uri source = null, bool prerelease = false) =>
+        public static Job WithNuGet(this Job job, string packageName, string? packageVersion = null, Uri? source = null, bool prerelease = false) =>
             job.WithCore(j => j.Infrastructure.NuGetReferences =
                 new NuGetReferenceList(j.Infrastructure.NuGetReferences ?? Array.Empty<NuGetReference>())
                     {

src/BenchmarkDotNet/Jobs/NugetReference.cs

@@ -5,7 +5,7 @@ namespace BenchmarkDotNet.Jobs
 {
     public class NuGetReference : IEquatable<NuGetReference>
     {
-        public NuGetReference(string packageName, string packageVersion, Uri source = null, bool prerelease = false)
+        public NuGetReference(string packageName, string packageVersion, Uri? source = null, bool prerelease = false)
         {
             if (string.IsNullOrWhiteSpace(packageName))
                 throw new ArgumentException("message", nameof(packageName));

src/BenchmarkDotNet/Loggers/AsyncProcessOutputReader.cs

@@ -19,7 +19,7 @@ internal class AsyncProcessOutputReader : IDisposable
 
         private long status;
 
-        internal AsyncProcessOutputReader(Process process, bool logOutput = false, ILogger logger = null, bool readStandardError = true)
+        internal AsyncProcessOutputReader(Process process, bool logOutput = false, ILogger? logger = null, bool readStandardError = true)
         {
             if (!process.StartInfo.RedirectStandardOutput)
                 throw new NotSupportedException("set RedirectStandardOutput to true first");

src/BenchmarkDotNet/Loggers/ConsoleLogger.cs

@@ -21,7 +21,7 @@ private static readonly bool ConsoleSupportsColors
         private readonly Dictionary<LogKind, ConsoleColor> colorScheme;
 
         [PublicAPI]
-        public ConsoleLogger(bool unicodeSupport = false, Dictionary<LogKind, ConsoleColor> colorScheme = null)
+        public ConsoleLogger(bool unicodeSupport = false, Dictionary<LogKind, ConsoleColor>? colorScheme = null)
         {
             this.unicodeSupport = unicodeSupport;
             this.colorScheme = colorScheme ?? CreateColorfulScheme();

src/BenchmarkDotNet/Order/DefaultOrderer.cs

@@ -37,7 +37,7 @@ public DefaultOrderer(
         [PublicAPI]
         public virtual IEnumerable<BenchmarkCase> GetExecutionOrder(
             ImmutableArray<BenchmarkCase> benchmarkCases,
-            IEnumerable<BenchmarkLogicalGroupRule> order = null)
+            IEnumerable<BenchmarkLogicalGroupRule>? order = null)
         {
             var benchmarkComparer = new BenchmarkComparer(categoryComparer, paramsComparer, jobComparer, targetComparer, order);
             var list = benchmarkCases.ToList();
@@ -137,7 +137,7 @@ public string GetLogicalGroupKey(ImmutableArray<BenchmarkCase> allBenchmarksCase
 
         public virtual IEnumerable<IGrouping<string, BenchmarkCase>> GetLogicalGroupOrder(
             IEnumerable<IGrouping<string, BenchmarkCase>> logicalGroups,
-            IEnumerable<BenchmarkLogicalGroupRule> order = null)
+            IEnumerable<BenchmarkLogicalGroupRule>? order = null)
         {
             var benchmarkComparer = new BenchmarkComparer(categoryComparer, paramsComparer, jobComparer, targetComparer, order);
             var logicalGroupComparer = new LogicalGroupComparer(benchmarkComparer);

src/BenchmarkDotNet/Order/IOrderer.cs

@@ -11,7 +11,7 @@ namespace BenchmarkDotNet.Order
     public interface IOrderer
     {
         [PublicAPI]
-        IEnumerable<BenchmarkCase> GetExecutionOrder(ImmutableArray<BenchmarkCase> benchmarksCase, IEnumerable<BenchmarkLogicalGroupRule> order = null);
+        IEnumerable<BenchmarkCase> GetExecutionOrder(ImmutableArray<BenchmarkCase> benchmarksCase, IEnumerable<BenchmarkLogicalGroupRule>? order = null);
 
         [PublicAPI]
         IEnumerable<BenchmarkCase> GetSummaryOrder(ImmutableArray<BenchmarkCase> benchmarksCases, Summary summary);
@@ -24,7 +24,7 @@ public interface IOrderer
 
         [PublicAPI]
         IEnumerable<IGrouping<string, BenchmarkCase>> GetLogicalGroupOrder(IEnumerable<IGrouping<string, BenchmarkCase>> logicalGroups,
-            IEnumerable<BenchmarkLogicalGroupRule> order = null);
+            IEnumerable<BenchmarkLogicalGroupRule>? order = null);
 
         [PublicAPI]
         bool SeparateLogicalGroups { get; }

src/BenchmarkDotNet/Reports/Summary.cs

@@ -48,7 +48,7 @@ public Summary(
             CultureInfo cultureInfo,
             ImmutableArray<ValidationError> validationErrors,
             ImmutableArray<IColumnHidingRule> columnHidingRules,
-            SummaryStyle summaryStyle = null)
+            SummaryStyle? summaryStyle = null)
         {
             Title = title;
             ResultsDirectoryPath = resultsDirectoryPath;

src/BenchmarkDotNet/Reports/SummaryTable.cs

@@ -24,7 +24,7 @@ public class SummaryTable
         public SummaryStyle EffectiveSummaryStyle { get; }
         public bool SeparateLogicalGroups { get; }
 
-        internal SummaryTable(Summary summary, SummaryStyle style = null)
+        internal SummaryTable(Summary summary, SummaryStyle? style = null)
         {
             Summary = summary;
 

src/BenchmarkDotNet/Running/Descriptor.cs

@@ -31,14 +31,14 @@ public class Descriptor : IEquatable<Descriptor>
         public Descriptor(
             Type type,
             MethodInfo workloadMethod,
-            MethodInfo globalSetupMethod = null,
-            MethodInfo globalCleanupMethod = null,
-            MethodInfo iterationSetupMethod = null,
-            MethodInfo iterationCleanupMethod = null,
-            string description = null,
-            string additionalLogic = null,
+            MethodInfo? globalSetupMethod = null,
+            MethodInfo? globalCleanupMethod = null,
+            MethodInfo? iterationSetupMethod = null,
+            MethodInfo? iterationCleanupMethod = null,
+            string? description = null,
+            string? additionalLogic = null,
             bool baseline = false,
-            string[] categories = null,
+            string[]? categories = null,
             int operationsPerInvoke = 1,
             int methodIndex = 0)
         {

src/BenchmarkDotNet/Toolchains/CoreRun/CoreRunPublisher.cs

@@ -11,7 +11,7 @@ namespace BenchmarkDotNet.Toolchains.CoreRun
 {
     public class CoreRunPublisher : IBuilder
     {
-        public CoreRunPublisher(FileInfo coreRun, FileInfo customDotNetCliPath = null)
+        public CoreRunPublisher(FileInfo coreRun, FileInfo? customDotNetCliPath = null)
         {
             CoreRun = coreRun;
             DotNetCliPublisher = new DotNetCliPublisher(customDotNetCliPath?.FullName);

src/BenchmarkDotNet/Toolchains/CoreRun/CoreRunToolchain.cs

@@ -21,7 +21,7 @@ public class CoreRunToolchain : IToolchain
         /// <param name="restorePath">the directory to restore packages to</param>
         public CoreRunToolchain(FileInfo coreRun, bool createCopy = true,
             string targetFrameworkMoniker = "netcoreapp2.1",
-            FileInfo customDotNetCliPath = null, DirectoryInfo restorePath = null,
+            FileInfo? customDotNetCliPath = null, DirectoryInfo? restorePath = null,
             string displayName = "CoreRun")
         {
             if (coreRun == null) throw new ArgumentNullException(nameof(coreRun));

src/BenchmarkDotNet/Toolchains/CsProj/CsProjClassicNetToolchain.cs

@@ -25,7 +25,7 @@ public class CsProjClassicNetToolchain : Toolchain
 
         internal string CustomDotNetCliPath { get; }
 
-        private CsProjClassicNetToolchain(string targetFrameworkMoniker, string name, string packagesPath = null, string customDotNetCliPath = null)
+        private CsProjClassicNetToolchain(string targetFrameworkMoniker, string name, string? packagesPath = null, string? customDotNetCliPath = null)
             : base(name,
                 new CsProjGenerator(targetFrameworkMoniker, customDotNetCliPath, packagesPath, runtimeFrameworkVersion: null, isNetCore: false),
                 new DotNetCliBuilder(targetFrameworkMoniker, customDotNetCliPath),
@@ -34,7 +34,7 @@ private CsProjClassicNetToolchain(string targetFrameworkMoniker, string name, st
             CustomDotNetCliPath = customDotNetCliPath;
         }
 
-        public static IToolchain From(string targetFrameworkMoniker, string packagesPath = null, string customDotNetCliPath = null)
+        public static IToolchain From(string targetFrameworkMoniker, string? packagesPath = null, string? customDotNetCliPath = null)
             => new CsProjClassicNetToolchain(targetFrameworkMoniker, targetFrameworkMoniker, packagesPath, customDotNetCliPath);
 
         public override IEnumerable<ValidationError> Validate(BenchmarkCase benchmarkCase, IResolver resolver)

src/BenchmarkDotNet/Toolchains/DotNetCli/DotNetCliBuilder.cs

@@ -17,7 +17,7 @@ public class DotNetCliBuilder : IBuilder
         private bool RetryFailedBuildWithNoDeps { get; }
 
         [PublicAPI]
-        public DotNetCliBuilder(string targetFrameworkMoniker, string customDotNetCliPath = null, bool logOutput = false, bool retryFailedBuildWithNoDeps = true)
+        public DotNetCliBuilder(string targetFrameworkMoniker, string? customDotNetCliPath = null, bool logOutput = false, bool retryFailedBuildWithNoDeps = true)
         {
             TargetFrameworkMoniker = targetFrameworkMoniker;
             CustomDotNetCliPath = customDotNetCliPath;