Add support for multiple output formats separated by a comma

src/coverlet.core/Reporters/ReporterFactory.cs

@@ -1,22 +1,25 @@
 using System.Linq;
+using System.Collections.Generic;
 
 namespace Coverlet.Core.Reporters
 {
     public class ReporterFactory
     {
-        private string _format;
+        private IEnumerable<string> _formats;
         private IReporter[] _reporters;
 
-        public ReporterFactory(string format)
+        public ReporterFactory(string formats)
         {
-            _format = format;
+            _formats = formats.Split(',');
             _reporters = new IReporter[] {
                 new JsonReporter(), new LcovReporter(),
                 new OpenCoverReporter(), new CoberturaReporter()
             };
         }
 
-        public IReporter CreateReporter()
-            => _reporters.FirstOrDefault(r => r.Format == _format);
+        public IEnumerable<IReporter> CreateReporters()
+        {
+            return _reporters.Where(r => _formats.Contains(r.Format));
+        }
     }
 }

src/coverlet.msbuild.tasks/CoverageResultTask.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.IO;
 using ConsoleTables;
 
@@ -49,13 +50,16 @@ public override bool Execute()
                 if (!Directory.Exists(directory))
                     Directory.CreateDirectory(directory);
 
-                IReporter reporter = new ReporterFactory(_format).CreateReporter();
-                if (reporter == null)
+                var reporters = new List<IReporter>(new ReporterFactory(_format).CreateReporters());
+                if (reporters.Count != _format.Split(',').Length)
                     throw new Exception($"Specified output format '{_format}' is not supported");
 
-                _filename = _filename + "." + reporter.Extension;
-                Console.WriteLine($"  Generating report '{_filename}'");
-                File.WriteAllText(_filename, reporter.Report(result));
+                foreach(var reporter in reporters)
+                {
+                    var reportFilename = _filename + "." + reporter.Extension;
+                    Console.WriteLine($"  Generating report '{reportFilename}'");
+                    File.WriteAllText(reportFilename, reporter.Report(result));
+                }
 
                 double total = 0;
                 CoverageSummary summary = new CoverageSummary();

test/coverlet.core.tests/Reporters/ReporterFactoryTests.cs

@@ -6,13 +6,41 @@ namespace Coverlet.Core.Reporters.Tests
     public class ReporterFactoryTests
     {
         [Fact]
-        public void TestCreateReporter()
+        public void TestCreateReportersWithSingleFormat()
         {
-            Assert.Equal(typeof(JsonReporter), new ReporterFactory("json").CreateReporter().GetType());
-            Assert.Equal(typeof(LcovReporter), new ReporterFactory("lcov").CreateReporter().GetType());
-            Assert.Equal(typeof(OpenCoverReporter), new ReporterFactory("opencover").CreateReporter().GetType());
-            Assert.Equal(typeof(CoberturaReporter), new ReporterFactory("cobertura").CreateReporter().GetType());
-            Assert.Null(new ReporterFactory("").CreateReporter());
+            Assert.Collection(
+                new ReporterFactory("json").CreateReporters(),
+                reporter => Assert.IsType<JsonReporter>(reporter));
+            Assert.Collection(
+                new ReporterFactory("lcov").CreateReporters(),
+                reporter => Assert.IsType<LcovReporter>(reporter));
+            Assert.Collection(
+                new ReporterFactory("opencover").CreateReporters(),
+                reporter => Assert.IsType<OpenCoverReporter>(reporter));
+            Assert.Collection(
+                new ReporterFactory("cobertura").CreateReporters(),
+                reporter => Assert.IsType<CoberturaReporter>(reporter));
+            Assert.Empty(new ReporterFactory("").CreateReporters());
+        }
+
+        [Fact]
+        public void TestCreateReportersWithMultipleFormats()
+        {
+            Assert.Collection(
+                new ReporterFactory("json,lcov").CreateReporters(),
+                reporter => Assert.IsType<JsonReporter>(reporter),
+                reporter => Assert.IsType<LcovReporter>(reporter));
+            Assert.Collection(
+                new ReporterFactory("json,lcov,opencover").CreateReporters(),
+                reporter => Assert.IsType<JsonReporter>(reporter),
+                reporter => Assert.IsType<LcovReporter>(reporter),
+                reporter => Assert.IsType<OpenCoverReporter>(reporter));
+            Assert.Collection(
+                new ReporterFactory("json,lcov,opencover,cobertura").CreateReporters(),
+                reporter => Assert.IsType<JsonReporter>(reporter),
+                reporter => Assert.IsType<LcovReporter>(reporter),
+                reporter => Assert.IsType<OpenCoverReporter>(reporter),
+                reporter => Assert.IsType<CoberturaReporter>(reporter));
         }
     }
 }