Add value transformers for parsed options (#47)

* Add generic IOptionBuilder<T>

* Add unit test

* Fix test

* Add IOptionBuilder<T> for Command options as well.

* Improve test coverage

* Update packages

* .NET Core 2.2

* Update to .NET Core 2.2

* Revert to .NET Core 2.0 otherwise tests don't run in VS 2019

* Update codecov

* Update some config

* Update config once more

* Update xml location

* Update nuspec

Author: Matthiee

CommandLineParser.Tests/CommandLineParser.Tests.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netcoreapp2.1</TargetFramework>
+    <TargetFramework>netcoreapp2.0</TargetFramework>
 
     <IsPackable>false</IsPackable>
 
@@ -11,14 +11,14 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="coverlet.msbuild" Version="2.5.0">
+    <PackageReference Include="coverlet.msbuild" Version="2.6.3">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.8.0" />
-    <PackageReference Include="Moq" Version="4.10.0" />
-    <PackageReference Include="xunit" Version="2.4.0" />
-    <PackageReference Include="xunit.runner.visualstudio" Version="2.4.0">
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.2.0" />
+    <PackageReference Include="Moq" Version="4.12.0" />
+    <PackageReference Include="xunit" Version="2.4.1" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="2.4.1">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>
     </PackageReference>

CommandLineParser.Tests/CommandLineParserTests.cs

@@ -459,6 +459,76 @@ public void ConfigureTests()
             Assert.False(option.HasDefault);
         }
 
+        [Theory]
+        [InlineData(new string[] { "" }, "defaulttransformed", false)]
+        [InlineData(new string[] { "-m", "test" }, "testtransformed", false)]
+        [InlineData(new string[] { "--message", "test" }, "testtransformed", false)]
+        public void TransformationWorksAsExpected(string[] args, string expected, bool errors)
+        {
+            var parser = new CommandLineParser<AddOption>();
+
+            parser.Configure(a => a.Message)
+                .Name("m", "message")
+                .Required()
+                .Transform(msg => $"{msg}transformed")
+                .Default("default");
+
+            var result = parser.Parse(args);
+
+            Assert.Equal(errors, result.AssertNoErrors(false));
+
+            Assert.Equal(expected, result.Result.Message);
+        }
+
+        [Theory]
+        [InlineData(new string[] { "" }, 11, false)]
+        [InlineData(new string[] { "-i", "10" }, 20, false)]
+        [InlineData(new string[] { "--int", "10" }, 20, false)]
+        public void TransformationWorksAsExpectedForInts(string[] args, int expected, bool errors)
+        {
+            var parser = new CommandLineParser<IntOptions>();
+
+            parser.Configure(a => a.SomeInt)
+                .Name("i", "int")
+                .Required()
+                .Transform(value => value + 10)
+                .Default(1);
+
+            var result = parser.Parse(args);
+
+            Assert.Equal(errors, result.AssertNoErrors(false));
+
+            Assert.Equal(expected, result.Result.SomeInt);
+        }
+
+        [Theory]
+        [InlineData(new string[] { "cmd" }, 11, false)]
+        [InlineData(new string[] { "cmd", "-i", "10" }, 20, false)]
+        [InlineData(new string[] { "cmd", "--int", "10" }, 20, false)]
+        public void TransformationWorksAsExpectedForCommandOptions(string[] args, int expected, bool errors)
+        {
+            int outcome = -1;
+
+            var parser = new CommandLineParser();
+
+            var cmd = parser.AddCommand<IntOptions>()
+                .Name("cmd")
+                .Required()
+                .OnExecuting((_, i) => outcome = i.SomeInt);
+
+            cmd.Configure(a => a.SomeInt)
+                .Name("i", "int")
+                .Required()
+                .Transform(value => value + 10)
+                .Default(1);
+
+            var result = parser.Parse(args);
+
+            Assert.Equal(errors, result.AssertNoErrors(false));
+
+            Assert.Equal(expected, outcome);
+        }
+
         private class ObjOption
         {
             [Name("p"), Required]
@@ -493,5 +563,10 @@ private class OptionsWithThreeParams<T>
             public T Option2 { get; set; }
             public T Option3 { get; set; }
         }
+
+        private class IntOptions
+        {
+            public int SomeInt { get; set; }
+        }
     }
 }

CommandLineParser.Tests/XUnitExtensions.cs

@@ -11,14 +11,24 @@ public static LambdaExpression CreateLambda<TSource, TProperty>(Expression<Func<
             return expression;
         }
 
-        public static void AssertNoErrors<T>(this IParserResult<T> result)
+        public static bool AssertNoErrors<T>(this IParserResult<T> result, bool shouldThrow = true)
         {
             if (result == null)
                 throw new NullReferenceException("Parsing result was null");
 
             foreach (var err in result.Errors)
-                throw err;
-        }
+            {
+                if (shouldThrow)
+                {
+                    throw err;
+                }
+                else
+                {
+                    return true;
+                }
+            }
 
+            return false;
+        }
     }
 }

CommandLineParser.sln

@@ -1,13 +1,22 @@
 
 Microsoft Visual Studio Solution File, Format Version 12.00
-# Visual Studio 15
-VisualStudioVersion = 15.0.28010.2016
+# Visual Studio Version 16
+VisualStudioVersion = 16.0.29111.141
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "CommandLineParser", "CommandLineParser\CommandLineParser.csproj", "{02D41856-3E21-427E-94C3-2AF34F1C2264}"
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "CommandLineParser.Tests", "CommandLineParser.Tests\CommandLineParser.Tests.csproj", "{72442EFD-1112-4081-A910-8A792F870AD1}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SampleApp", "SampleApp\SampleApp.csproj", "{6871A016-97E8-48C5-B797-DD0FA3DD6288}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "SampleApp", "SampleApp\SampleApp.csproj", "{6871A016-97E8-48C5-B797-DD0FA3DD6288}"
+EndProject
+Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution Items", "{DA88EFDF-AD86-4772-B310-35A606D6D643}"
+	ProjectSection(SolutionItems) = preProject
+		.gitignore = .gitignore
+		appveyor.yml = appveyor.yml
+		build.cake = build.cake
+		LICENSE = LICENSE
+		README.md = README.md
+	EndProjectSection
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution

CommandLineParser/Abstractions/Command/ICommandBuilder'.cs

@@ -18,7 +18,7 @@ public interface ICommandBuilder<TOption, TSource> : ICommandConfigurationBuilde
         /// <typeparam name="TProperty">Type of the property</typeparam>
         /// <param name="selector">Model property to configure</param>
         /// <returns><see cref="IOptionBuilder"/></returns>
-        IOptionBuilder Configure<TProperty>(Expression<Func<TSource, TProperty>> selector);
+        IOptionBuilder<TProperty> Configure<TProperty>(Expression<Func<TSource, TProperty>> selector);
 
         /// <summary>
         /// Configures if the command is required

CommandLineParser/Abstractions/Command/ICommandConfigurationBuilder`.cs

@@ -17,7 +17,7 @@ public interface ICommandConfigurationBuilder<TSource>
         /// <typeparam name="TProperty">Type of the property</typeparam>
         /// <param name="selector">Model property to configure</param>
         /// <returns><see cref="IOptionBuilder"/></returns>
-        IOptionBuilder Configure<TProperty>(Expression<Func<TSource, TProperty>> selector);
+        IOptionBuilder<TProperty> Configure<TProperty>(Expression<Func<TSource, TProperty>> selector);
 
         /// <summary>
         /// Configures if the command is required

CommandLineParser/Abstractions/ICommandLineParser'.cs

@@ -7,6 +7,10 @@
 
 namespace MatthiWare.CommandLine.Abstractions
 {
+    /// <summary>
+    /// Command line parser
+    /// </summary>
+    /// <typeparam name="TOption">Argument options model</typeparam>
     public interface ICommandLineParser<TOption>
         where TOption : class, new()
     {
@@ -49,7 +53,7 @@ public interface ICommandLineParser<TOption>
         /// <typeparam name="TProperty">The property type</typeparam>
         /// <param name="selector">Property selector</param>
         /// <returns><see cref="IOptionBuilder"/></returns>
-        IOptionBuilder Configure<TProperty>(Expression<Func<TOption, TProperty>> selector);
+        IOptionBuilder<TProperty> Configure<TProperty>(Expression<Func<TOption, TProperty>> selector);
 
         /// <summary>
         /// Adds a new command  and allowes to configure it. 

CommandLineParser/Abstractions/IOptionBuilder'.cs renamed to CommandLineParser/Abstractions/IOptionBuilder.cs

@@ -1,4 +1,7 @@
-namespace MatthiWare.CommandLine.Abstractions
+using System;
+using System.Linq.Expressions;
+
+namespace MatthiWare.CommandLine.Abstractions
 {
     /// <summary>
     /// API for configuring options
@@ -15,30 +18,30 @@ public interface IOptionBuilder
         /// <summary>
         /// Help text to be displayed for this option
         /// </summary>
-        /// <param name="help"></param>
-        /// <returns></returns>
+        /// <param name="description">The description of the option</param>
+        /// <returns><see cref="IOptionBuilder"></see></returns>
         IOptionBuilder Description(string description);
 
         /// <summary>
         /// Specify the default value for this option
         /// </summary>
         /// <param name="defaultValue"></param>
-        /// <returns></returns>
+        /// <returns><see cref="IOptionBuilder"></see></returns>
         IOptionBuilder Default(object defaultValue);
 
         /// <summary>
         /// Configures the name for the option
         /// </summary>
         /// <param name="shortName">short name</param>
-        /// <returns></returns>
+        /// <returns><see cref="IOptionBuilder"></see></returns>
         IOptionBuilder Name(string shortName);
 
         /// <summary>
         /// Configures the name for the option
         /// </summary>
         /// <param name="shortName">Short name</param>
         /// <param name="longName">Long name</param>
-        /// <returns></returns>
+        /// <returns><see cref="IOptionBuilder"></see></returns>
         IOptionBuilder Name(string shortName, string longName);
     }
 }

CommandLineParser/Abstractions/IOptionBuilder`.cs

@@ -0,0 +1,54 @@
+using System;
+using System.Linq.Expressions;
+
+namespace MatthiWare.CommandLine.Abstractions
+{
+    /// <summary>
+    /// API for configuring options
+    /// </summary>
+    public interface IOptionBuilder<TOption> : IOptionBuilder
+    {
+        /// <summary>
+        /// Sets if the option is required
+        /// </summary>
+        /// <param name="required">Required or not</param>
+        /// <returns><see cref="IOptionBuilder"/></returns>
+        new IOptionBuilder<TOption> Required(bool required = true);
+
+        /// <summary>
+        /// Help text to be displayed for this option
+        /// </summary>
+        /// <param name="description">The description of the option</param>
+        /// <returns><see cref="IOptionBuilder{TOption}"></see></returns>
+        new IOptionBuilder<TOption> Description(string description);
+
+        /// <summary>
+        /// Specify the default value for this option
+        /// </summary>
+        /// <param name="defaultValue"></param>
+        /// <returns><see cref="IOptionBuilder{TOption}"></see></returns>
+        IOptionBuilder<TOption> Default(TOption defaultValue);
+
+        /// <summary>
+        /// Configures the name for the option
+        /// </summary>
+        /// <param name="shortName">short name</param>
+        /// <returns><see cref="IOptionBuilder{TOption}"></see></returns>
+        new IOptionBuilder<TOption> Name(string shortName);
+
+        /// <summary>
+        /// Configures the name for the option
+        /// </summary>
+        /// <param name="shortName">Short name</param>
+        /// <param name="longName">Long name</param>
+        /// <returns><see cref="IOptionBuilder{TOption}"></see></returns>
+        new IOptionBuilder<TOption> Name(string shortName, string longName);
+
+        /// <summary>
+        /// Transforms the parsed value using the transform function
+        /// </summary>
+        /// <param name="transformation">Transformation function</param>
+        /// <returns><see cref="IOptionBuilder{TOption}"></see></returns>
+        IOptionBuilder<TOption> Transform(Expression<Func<TOption, TOption>> transformation);
+    }
+}

CommandLineParser/Abstractions/IOptionConfigurator.cs

@@ -10,6 +10,6 @@ public interface IOptionConfigurator<TSource>
         /// </summary>
         /// <param name="selector">Property to configure</param>
         /// <returns><see cref="IOptionBuilder"/></returns>
-        IOptionBuilder Configure<TProperty>(Expression<Func<TSource, TProperty>> selector);
+        IOptionBuilder<TProperty> Configure<TProperty>(Expression<Func<TSource, TProperty>> selector);
     }
 }