Added teamcity reporter

Author: obtuse-whoosh

src/coverlet.console/Program.cs

@@ -74,13 +74,23 @@ static int Main(string[] args)
                     if (reporter == null)
                         throw new Exception($"Specified output format '{format}' is not supported");
 
-                    var filename = Path.GetFileName(dOutput);
-                    filename = (filename == string.Empty) ? $"coverage.{reporter.Extension}" : filename;
-                    filename = Path.HasExtension(filename) ? filename : $"{filename}.{reporter.Extension}";
-
-                    var report = Path.Combine(directory, filename);
-                    logger.LogInformation($"  Generating report '{report}'");
-                    File.WriteAllText(report, reporter.Report(result));
+                    if (reporter.UseConsoleOutput)
+                    {
+                        // Output to console
+                        logger.LogInformation("  Outputting results to console");
+                        logger.LogInformation(reporter.Report(result));
+                    }
+                    else
+                    {
+                        // Output to file
+                        var filename = Path.GetFileName(dOutput);
+                        filename = (filename == string.Empty) ? $"coverage.{reporter.Extension}" : filename;
+                        filename = Path.HasExtension(filename) ? filename : $"{filename}.{reporter.Extension}";
+
+                        var report = Path.Combine(directory, filename);
+                        logger.LogInformation($"  Generating report '{report}'");
+                        File.WriteAllText(report, reporter.Report(result));
+                    }
                 }
 
                 var summary = new CoverageSummary();

src/coverlet.core/Reporters/CoberturaReporter.cs

@@ -10,6 +10,8 @@ namespace Coverlet.Core.Reporters
 {
     public class CoberturaReporter : IReporter
     {
+        public bool UseConsoleOutput => false;
+
         public string Format => "cobertura";
 
         public string Extension => "cobertura.xml";

src/coverlet.core/Reporters/IReporter.cs

@@ -2,6 +2,7 @@ namespace Coverlet.Core.Reporters
 {
     public interface IReporter
     {
+        bool UseConsoleOutput { get; }
         string Format { get; }
         string Extension { get; }
         string Report(CoverageResult result);

src/coverlet.core/Reporters/JsonReporter.cs

@@ -4,6 +4,8 @@ namespace Coverlet.Core.Reporters
 {
     public class JsonReporter : IReporter
     {
+        public bool UseConsoleOutput => false;
+        
         public string Format => "json";
 
         public string Extension => "json";

src/coverlet.core/Reporters/LcovReporter.cs

@@ -6,6 +6,8 @@ namespace Coverlet.Core.Reporters
 {
     public class LcovReporter : IReporter
     {
+        public bool UseConsoleOutput => false;
+        
         public string Format => "lcov";
 
         public string Extension => "info";

src/coverlet.core/Reporters/OpenCoverReporter.cs

@@ -9,6 +9,8 @@ namespace Coverlet.Core.Reporters
 {
     public class OpenCoverReporter : IReporter
     {
+        public bool UseConsoleOutput => false;
+        
         public string Format => "opencover";
 
         public string Extension => "opencover.xml";

src/coverlet.core/Reporters/ReporterFactory.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Linq;
 using System.Collections.Generic;
+using coverlet.core.Reporters;
 
 namespace Coverlet.Core.Reporters
 {
@@ -14,7 +15,8 @@ public ReporterFactory(string format)
             _format = format;
             _reporters = new IReporter[] {
                 new JsonReporter(), new LcovReporter(),
-                new OpenCoverReporter(), new CoberturaReporter()
+                new OpenCoverReporter(), new CoberturaReporter(),
+                new TeamCityReporter()
             };
         }
 

src/coverlet.core/Reporters/TeamCityReporter.cs

@@ -0,0 +1,34 @@
+using Coverlet.Core;
+using Coverlet.Core.Reporters;
+using System.Text;
+
+namespace coverlet.core.Reporters
+{
+    public class TeamCityReporter : IReporter
+    {
+        public bool UseConsoleOutput => true;
+
+        public string Format => "teamcity";
+
+        public string Extension => null;
+
+        public string Report(CoverageResult result)
+        {
+            // Calculate coverage
+            var summary = new CoverageSummary();
+            var overallLineCoverage = summary.CalculateLineCoverage(result.Modules);
+            var overallBranchCoverage = summary.CalculateBranchCoverage(result.Modules);
+            var overallMethodCoverage = summary.CalculateMethodCoverage(result.Modules);
+
+            // Report coverage
+            var stringBuilder = new StringBuilder();
+            var teamCityServiceMessageWriter = new TeamCityServiceMessageWriter(s => stringBuilder.AppendLine(s));
+            teamCityServiceMessageWriter.OutputLineCoverage(overallLineCoverage);
+            teamCityServiceMessageWriter.OutputBranchCoverage(overallBranchCoverage);
+            teamCityServiceMessageWriter.OutputMethodCoverage(overallMethodCoverage);
+
+            // Return a placeholder
+            return stringBuilder.ToString();
+        }
+    }
+}

src/coverlet.core/TeamCityServiceMessageWriter.cs

@@ -62,7 +62,7 @@ public void OutputMethodCoverage(CoverageDetails coverageDetails)
 
         private void OutputTeamCityServiceMessage(string key, object value)
         {
-            _writer($"##teamcity[buildStatisticValue key='{key}' value='{value}']");
+            _writer?.Invoke($"##teamcity[buildStatisticValue key='{key}' value='{value}']");
         }
     }
 }

src/coverlet.msbuild.tasks/CoverageResultTask.cs

@@ -75,13 +75,23 @@ public override bool Execute()
                     if (reporter == null)
                         throw new Exception($"Specified output format '{format}' is not supported");
 
-                    var filename = Path.GetFileName(_output);
-                    filename = (filename == string.Empty) ? $"coverage.{reporter.Extension}" : filename;
-                    filename = Path.HasExtension(filename) ? filename : $"{filename}.{reporter.Extension}";
-
-                    var report = Path.Combine(directory, filename);
-                    Console.WriteLine($"  Generating report '{report}'");
-                    File.WriteAllText(report, reporter.Report(result));
+                    if (reporter.UseConsoleOutput)
+                    {
+                        // Output to console
+                        Console.WriteLine("  Outputting results to console");
+                        Console.WriteLine(reporter.Report(result));
+                    }
+                    else
+                    {
+                        // Output to file
+                        var filename = Path.GetFileName(_output);
+                        filename = (filename == string.Empty) ? $"coverage.{reporter.Extension}" : filename;
+                        filename = Path.HasExtension(filename) ? filename : $"{filename}.{reporter.Extension}";
+
+                        var report = Path.Combine(directory, filename);
+                        Console.WriteLine($"  Generating report '{report}'");
+                        File.WriteAllText(report, reporter.Report(result));
+                    }
                 }
 
                 var thresholdFailed = false;