fixes #131 by preferring string overloaded methods

Author: nbaztec

.gitignore

@@ -25,6 +25,9 @@ bld/
 # Visual Studo 2015 cache/options directory
 .vs/
 
+# JetBrains project files
+.idea/
+
 # MSTest test Results
 [Tt]est[Rr]esult*/
 [Bb]uild[Ll]og.*

src/Serilog.Settings.Configuration/Settings/Configuration/ConfigurationReader.cs

@@ -321,7 +321,16 @@ internal static MethodInfo SelectConfigurationMethod(IEnumerable<MethodInfo> can
             return candidateMethods
                 .Where(m => m.Name == name &&
                             m.GetParameters().Skip(1).All(p => p.HasDefaultValue || suppliedArgumentValues.Any(s => s.Key == p.Name)))
-                .OrderByDescending(m => m.GetParameters().Count(p => suppliedArgumentValues.Any(s => s.Key == p.Name)))
+                .OrderByDescending(m =>
+                {
+                    var matchingArgs = m.GetParameters().Where(p => suppliedArgumentValues.Any(s => s.Key == p.Name)).ToList();
+
+                    // Prefer the configuration method with most number of matching arguments and of those the ones with
+                    // the most string type parameters to predict best match with least type casting
+                    return new Tuple<int, int>(
+                        matchingArgs.Count,
+                        matchingArgs.Count(p => p.ParameterType == typeof(string)));
+                })
                 .FirstOrDefault();
         }
 

test/Serilog.Settings.Configuration.Tests/ConfigurationReaderTests.cs

@@ -165,5 +165,20 @@ public void MethodsAreSelectedBasedOnCountOfMatchedArguments()
             var selected = ConfigurationReader.SelectConfigurationMethod(options, "DummyRollingFile", suppliedArguments);
             Assert.Equal(typeof(ITextFormatter), selected.GetParameters()[1].ParameterType);
         }
+
+        [Fact]
+        public void MethodsAreSelectedBasedOnCountOfMatchedArgumentsAndThenStringType()
+        {
+            var options = typeof(DummyLoggerConfigurationWithMultipleMethodsExtensions).GetTypeInfo().DeclaredMethods.ToList();
+            Assert.Equal(3, options.Count(mi => mi.Name == "DummyRollingFile"));
+            var suppliedArguments = new Dictionary<string, IConfigurationArgumentValue>()
+            {
+                { "pathFormat", new StringArgumentValue(() => "C:\\") },
+                { "formatter", new StringArgumentValue(() => "SomeFormatter, SomeAssembly") }
+            };
+
+            var selected = ConfigurationReader.SelectConfigurationMethod(options, "DummyRollingFile", suppliedArguments);
+            Assert.Equal(typeof(string), selected.GetParameters()[2].ParameterType);
+        }
     }
 }

test/Serilog.Settings.Configuration.Tests/DummyLoggerConfigurationWithMultipleMethodsExtensions.cs

@@ -0,0 +1,42 @@
+using System;
+using Serilog.Configuration;
+using Serilog.Events;
+using Serilog.Formatting;
+
+namespace Serilog.Settings.Configuration.Tests
+{
+    using System.Collections.Generic;
+
+    static class DummyLoggerConfigurationWithMultipleMethodsExtensions
+    {
+        public static LoggerConfiguration DummyRollingFile(
+            LoggerSinkConfiguration loggerSinkConfiguration,
+            ITextFormatter formatter,
+            IEnumerable<string> pathFormat,
+            LogEventLevel restrictedToMinimumLevel = LevelAlias.Minimum,
+            string outputTemplate = null,
+            IFormatProvider formatProvider = null)
+        {
+            return null;
+        }
+
+        public static LoggerConfiguration DummyRollingFile(
+            LoggerSinkConfiguration loggerSinkConfiguration,
+            ITextFormatter formatter,
+            string pathFormat,
+            LogEventLevel restrictedToMinimumLevel = LevelAlias.Minimum,
+            string outputTemplate = null,
+            IFormatProvider formatProvider = null)
+        {
+            return null;
+        }
+
+        public static LoggerConfiguration DummyRollingFile(
+            LoggerSinkConfiguration loggerSinkConfiguration,
+            string pathFormat,
+            LogEventLevel restrictedToMinimumLevel = LevelAlias.Minimum)
+        {
+            return null;
+        }
+    }
+}