Improve FeatureParser performance

CHANGELOG.md

@@ -29,6 +29,7 @@ This document is formatted according to the principles of [Keep A CHANGELOG](htt
 ### Fixed
 - Cache the NUnit feature scan results to improve performance on large solutions ([503](https://github.com/picklesdoc/pickles/pull/503)) (by [@tlecomte](https://github.com/tlecomte))
 - Use lookups in JSONDocumentation Builder to improve performance on large solutions ([504](https://github.com/picklesdoc/pickles/pull/504)) (by [@tlecomte](https://github.com/tlecomte))
+- Cache LanguageServices and GherkinDialectProvider in FeatureParser to improve performance on large solutions ([505](https://github.com/picklesdoc/pickles/pull/505)) (by [@tlecomte](https://github.com/tlecomte))
 
 ### Security
 

src/Pickles/Pickles.Test/ObjectModel/Factory.cs

@@ -38,7 +38,8 @@ internal Mapper CreateMapper(string defaultLanguage = "en")
 
         internal Mapper CreateMapper(IConfiguration configuration, string defaultLanguage = "en")
         {
-            var mapper = new Mapper(configuration, defaultLanguage);
+            var languageServices = new LanguageServices(defaultLanguage);
+            var mapper = new Mapper(configuration, languageServices);
             return mapper;
         }
 

src/Pickles/Pickles/FeatureParser.cs

@@ -19,7 +19,9 @@
 //  --------------------------------------------------------------------------------------------------------------------
 
 using System;
+using System.Collections.Generic;
 using System.Linq;
+using Gherkin;
 using PicklesDoc.Pickles.ObjectModel;
 
 using TextReader = System.IO.TextReader;
@@ -32,6 +34,10 @@ public class FeatureParser
 
         private readonly DescriptionProcessor descriptionProcessor = new DescriptionProcessor();
 
+        private readonly LanguageServicesRegistry languageServicesRegistry = new LanguageServicesRegistry();
+
+        private readonly IDictionary<string, IGherkinDialectProvider> dialectProviderCache = new Dictionary<string, IGherkinDialectProvider>();
+
         public FeatureParser(IConfiguration configuration)
         {
             this.configuration = configuration;
@@ -41,14 +47,16 @@ public Feature Parse(TextReader featureFileReader)
         {
             var language = this.DetermineLanguage();
             var gherkinParser = new Gherkin.Parser();
+            var dialectProvider = this.GetDialectProvider(language);
 
             try
             {
                 Gherkin.Ast.GherkinDocument gherkinDocument = gherkinParser.Parse(
                     new Gherkin.TokenScanner(featureFileReader),
-                    new Gherkin.TokenMatcher(new CultureAwareDialectProvider(language)));
+                    new Gherkin.TokenMatcher(dialectProvider));
 
-                Feature result = new Mapper(this.configuration, gherkinDocument.Feature.Language).MapToFeature(gherkinDocument);
+                var languageServices = this.languageServicesRegistry.GetLanguageServicesForLanguage(gherkinDocument.Feature.Language);
+                Feature result = new Mapper(this.configuration, languageServices).MapToFeature(gherkinDocument);
                 result = this.RemoveFeatureWithExcludeTags(result);
 
                 if (result != null)
@@ -62,6 +70,22 @@ public Feature Parse(TextReader featureFileReader)
             }
         }
 
+        private IGherkinDialectProvider GetDialectProvider(string language)
+        {
+            IGherkinDialectProvider dialectProvider;
+            if (this.dialectProviderCache.ContainsKey(language))
+            {
+                dialectProvider = this.dialectProviderCache[language];
+            }
+            else
+            {
+                dialectProvider = new CultureAwareDialectProvider(language);
+                this.dialectProviderCache[language] = dialectProvider;
+            }
+
+            return dialectProvider;
+        }
+
         private string DetermineLanguage()
         {
             string language = null;

src/Pickles/Pickles/LanguageServicesRegistry.cs

@@ -17,13 +17,26 @@
 //  limitations under the License.
 //  </copyright>
 //  --------------------------------------------------------------------------------------------------------------------
+using System.Collections.Generic;
+
 namespace PicklesDoc.Pickles
 {
     public class LanguageServicesRegistry : ILanguageServicesRegistry
     {
+        private static readonly IDictionary<string, ILanguageServices> LanguageServices = new Dictionary<string, ILanguageServices>();
+
         public ILanguageServices GetLanguageServicesForLanguage(string language)
         {
-            return new LanguageServices(language ?? DefaultLanguage);
+            language = language ?? DefaultLanguage;
+
+            if (LanguageServices.ContainsKey(language))
+            {
+                return LanguageServices[language];
+            }
+
+            var services = new LanguageServices(language);
+            LanguageServices[language] = services;
+            return services;
         }
 
         public string DefaultLanguage

src/Pickles/Pickles/ObjectModel/Mapper.cs

@@ -35,10 +35,10 @@ public class Mapper
 
         private readonly ILanguageServices languageServices;
 
-        public Mapper(IConfiguration configuration, string featureLanguage)
+        public Mapper(IConfiguration configuration, ILanguageServices languageServices)
         {
             this.configuration = configuration;
-            this.languageServices = new LanguageServices(featureLanguage);
+            this.languageServices = languageServices;
         }
 
         public string MapToString(G.TableCell cell)