Improve code-behind feature file compilation speed

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## Improvements:
 
 * Enhance BoDi error handling to provide the name of the interface being registered when that interface has already been resolved (#324)
+* Improve code-behind feature file compilation speed (#336)
 
 ## Bug fixes:
 

Reqnroll.Generator/Generation/ScenarioPartHelper.cs

@@ -1,3 +1,4 @@
+using System;
 using System.CodeDom;
 using System.Collections.Generic;
 using System.Linq;
@@ -94,9 +95,18 @@ public void GenerateStep(TestClassGenerationContext generationContext, List<Code
 
             using (new SourceLineScope(_reqnrollConfiguration, _codeDomHelper, statements, generationContext.Document.SourceFilePath, gherkinStep.Location))
             {
+                string stepKeyWord = scenarioStep.StepKeyword switch
+                {
+                    StepKeyword.Given => "Given",
+                    StepKeyword.When => "When",
+                    StepKeyword.Then => "Then",
+                    StepKeyword.And => "And",
+                    StepKeyword.But => "But",
+                    _ => throw new NotImplementedException(),
+                };
                 var expression = new CodeMethodInvokeExpression(
                     testRunnerField,
-                    scenarioStep.StepKeyword + "Async",
+                    stepKeyWord + "Async",
                     arguments.ToArray());
 
                 _codeDomHelper.MarkCodeMethodInvokeExpressionAsAwait(expression);

Reqnroll.Generator/TestGenerator.cs

@@ -106,7 +106,9 @@ protected string GetGeneratedTestCode(FeatureFileInput featureFileInput)
 
                 outputWriter.Flush();
                 var generatedTestCode = outputWriter.ToString();
-                return FixVb(generatedTestCode);
+                if (codeDomHelper.TargetLanguage == CodeDomProviderLanguage.VB)
+                    generatedTestCode = FixVb(generatedTestCode);
+                return generatedTestCode;
             }
         }
 
@@ -121,14 +123,17 @@ private string FixVBNetGlobalNamespace(string generatedTestCode)
                     .Replace("Global.GlobalVBNetNamespace", "Global")
                     .Replace("GlobalVBNetNamespace", "Global");
         }
-
+
+        static readonly Lazy<Regex> VBFixAsyncFunctionRegex = new Lazy<Regex>(() => new Regex(@"^([^\n]*)Function[ ]*([^(\n]*)(\([^\n]*\)[ ]*As) async([^\n]*)$", RegexOptions.Multiline));
+        static readonly Lazy<Regex> VBFixAsyncSubRegex = new Lazy<Regex>(() => new Regex(@"^([^\n]*)Sub[ ]*([^(\n]*)(\([^\n]*\)[ ]*As) async([^\n]*)$", RegexOptions.Multiline));
+
         /// <summary>
         /// This is a workaround to allow async/await calls in VB.NET. Works in cooperation with CodeDomHelper.MarkCodeMemberMethodAsAsync() method
         /// </summary>
         private string FixVBNetAsyncMethodDeclarations(string generatedTestCode)
         {
-            var functionRegex = new Regex(@"^([^\n]*)Function[ ]*([^(\n]*)(\([^\n]*\)[ ]*As) async([^\n]*)$", RegexOptions.Multiline);
-            var subRegex = new Regex(@"^([^\n]*)Sub[ ]*([^(\n]*)(\([^\n]*\)[ ]*As) async([^\n]*)$", RegexOptions.Multiline);
+            var functionRegex = VBFixAsyncFunctionRegex.Value;
+            var subRegex = VBFixAsyncSubRegex.Value;
 
             var result = functionRegex.Replace(generatedTestCode, "$1 Async Function $2$3$4");
             result = subRegex.Replace(result, "$1 Async Sub $2$3$4");

Reqnroll.Parser/ReqnrollGherkinParser.cs

@@ -11,7 +11,13 @@ namespace Reqnroll.Parser
     public class ReqnrollGherkinParser : IGherkinParser
     {
         private readonly IGherkinDialectProvider dialectProvider;
-        private readonly List<ISemanticValidator> semanticValidators;
+        private static readonly List<ISemanticValidator> semanticValidators = new List<ISemanticValidator>(4)
+        {
+            new DuplicateScenariosValidator(),
+            new DuplicateExamplesValidator(),
+            new MissingExamplesValidator(),
+            new DuplicateExamplesColumnHeadersValidator()
+        };
 
         public IGherkinDialectProvider DialectProvider
         {
@@ -26,13 +32,7 @@ public ReqnrollGherkinParser(IGherkinDialectProvider dialectProvider)
         public ReqnrollGherkinParser(CultureInfo defaultLanguage)
             : this(new ReqnrollGherkinDialectProvider(defaultLanguage.Name))
         {
-            semanticValidators = new List<ISemanticValidator>
-            {
-                new DuplicateScenariosValidator(),
-                new DuplicateExamplesValidator(),
-                new MissingExamplesValidator(),
-                new DuplicateExamplesColumnHeadersValidator()
-            };
+
         }
 
         private static StepKeyword GetStepKeyword(GherkinDialect dialect, string stepKeyword)

Reqnroll.Parser/ReqnrollGherkinParserFactory.cs

@@ -1,12 +1,17 @@
 using Gherkin;
+using System;
+using System.Collections.Concurrent;
 using System.Globalization;
 
 namespace Reqnroll.Parser
 {
     public class ReqnrollGherkinParserFactory : IGherkinParserFactory
     {
+        readonly ConcurrentDictionary<string, ReqnrollGherkinDialectProvider> _CachedDialectProvider = new ConcurrentDictionary<string, ReqnrollGherkinDialectProvider>();
+        static readonly Func<string, ReqnrollGherkinDialectProvider> _DialectProviderFactory = (defaultLanguage) => new ReqnrollGherkinDialectProvider(defaultLanguage);
+
         public IGherkinParser Create(IGherkinDialectProvider dialectProvider) => new ReqnrollGherkinParser(dialectProvider);
 
-        public IGherkinParser Create(CultureInfo cultureInfo) => new ReqnrollGherkinParser(cultureInfo);
+        public IGherkinParser Create(CultureInfo cultureInfo) => new ReqnrollGherkinParser(_CachedDialectProvider.GetOrAdd(cultureInfo.Name, _DialectProviderFactory));
     }
 }

Reqnroll/Parser/ReqnrollGherkinDialectProvider.cs

@@ -13,16 +13,13 @@ public override GherkinDialect GetDialect(string language, Location location)
         {
             if (language.Contains("-"))
             {
-                try
-                {
-                    return base.GetDialect(language, location);
-                }
-                catch (NoSuchLanguageException)
-                {
-                    var languageBase = language.Split('-')[0];
-                    var languageBaseDialect = base.GetDialect(languageBase, location);
-                    return new GherkinDialect(language, languageBaseDialect.FeatureKeywords, languageBaseDialect.RuleKeywords, languageBaseDialect.BackgroundKeywords, languageBaseDialect.ScenarioKeywords, languageBaseDialect.ScenarioOutlineKeywords, languageBaseDialect.ExamplesKeywords, languageBaseDialect.GivenStepKeywords, languageBaseDialect.WhenStepKeywords, languageBaseDialect.ThenStepKeywords, languageBaseDialect.AndStepKeywords, languageBaseDialect.ButStepKeywords);
-                }
+                // Use TryGetDialect to avoid NoSuchLanguageException, if culture specific language is not present
+                if (TryGetDialect(language, location, out var dialect))
+                    return dialect;
+
+                var languageBase = language.Split('-')[0];
+                var languageBaseDialect = base.GetDialect(languageBase, location);
+                return new GherkinDialect(language, languageBaseDialect.FeatureKeywords, languageBaseDialect.RuleKeywords, languageBaseDialect.BackgroundKeywords, languageBaseDialect.ScenarioKeywords, languageBaseDialect.ScenarioOutlineKeywords, languageBaseDialect.ExamplesKeywords, languageBaseDialect.GivenStepKeywords, languageBaseDialect.WhenStepKeywords, languageBaseDialect.ThenStepKeywords, languageBaseDialect.AndStepKeywords, languageBaseDialect.ButStepKeywords);
             }
 
             return base.GetDialect(language, location);