addressing first comments

Author: ido-namely

src/coverlet.core/Coverage.cs

@@ -15,7 +15,7 @@ public class Coverage
         private IEnumerable<string> _excludedFiles;
         private List<InstrumenterResult> _results;
 
-        public Coverage(string module, string identifier, IEnumerable<string> excludedFiles)
+        public Coverage(string module, string identifier, IEnumerable<string> excludedFiles = null)
         {
             _module = module;
             _identifier = identifier;

src/coverlet.core/Helpers/InstrumentationHelper.cs

@@ -110,7 +110,7 @@ public static void DeleteHitsFile(string path)
         }
 
         public static string[] GetExcludedFiles(string[] exclusionRules, string parentDir) {
-            if (exclusionRules == null || exclusionRules.Length == 0 ) return null;
+            if (!(exclusionRules?.Length > 0) ) return null;
             var matcher = new Matcher();
             foreach (var exclusionRule in exclusionRules)
             {
@@ -121,11 +121,7 @@ public static string[] GetExcludedFiles(string[] exclusionRules, string parentDi
 
             var fileMatchResult = matcher.Execute(new DirectoryInfoWrapper(directoryInfo));
             return fileMatchResult.Files
-                .Select(
-                    f => System.IO.Path.GetFullPath(
-                        System.IO.Path.Combine(directoryInfo.ToString(), f.Path)
-                    )
-                )
+                .Select(f => Path.GetFullPath(Path.Combine(directoryInfo.ToString(), f.Path)))
                 .ToArray();
         }
     }

src/coverlet.core/Instrumentation/Instrumenter.cs

@@ -24,7 +24,7 @@ public Instrumenter(string module, string identifier, IEnumerable<string> exclud
         {
             _module = module;
             _identifier = identifier;
-            _excludedFiles = excludedFiles;
+            _excludedFiles = excludedFiles ?? Enumerable.Empty<string>();
         }
 
         public bool CanInstrument() => InstrumentationHelper.HasPdb(_module);
@@ -65,8 +65,8 @@ private void InstrumentModule()
 
                     foreach (var method in type.Methods)
                     {
-                        var sourceFiles = method.DebugInformation.SequencePoints.Select(s => s.Document.Url).Distinct();
-                        if (_excludedFiles != null && sourceFiles.Any(_excludedFiles.Contains)) {
+                        var sourceFile = method.DebugInformation.SequencePoints.Select(s => s.Document.Url).FirstOrDefault();
+                        if (!string.IsNullOrEmpty(sourceFile) && _excludedFiles.Contains(sourceFile)) {
                             continue;
                         }
                         if (!method.CustomAttributes.Any(a => a.AttributeType.Name == "ExcludeFromCoverageAttribute" || a.AttributeType.Name == "ExcludeFromCoverage"))

test/coverlet.core.tests/CoverageTests.cs

@@ -21,7 +21,7 @@ public void TestCoverage()
 
             File.Copy(module, tempModule, true);
 
-            var coverage = new Coverage(tempModule, identifier, null);
+            var coverage = new Coverage(tempModule, identifier);
             coverage.PrepareModules();
 
             var result = coverage.GetCoverageResult();

test/coverlet.core.tests/Instrumentation/InstrumenterTests.cs

@@ -3,7 +3,6 @@
 
 using Xunit;
 using Coverlet.Core.Instrumentation;
-using Coverlet.MSbuild.Tasks;
 
 namespace Coverlet.Core.Instrumentation.Tests
 {

test/coverlet.core.tests/coverlet.core.tests.csproj

@@ -17,7 +17,6 @@
 
   <ItemGroup>
     <ProjectReference Include="..\..\src\coverlet.core\coverlet.core.csproj" />
-    <ProjectReference Include="..\..\src\coverlet.msbuild.tasks\coverlet.msbuild.tasks.csproj" />
   </ItemGroup>
 
   <Import Project="$(MSBuildThisFileDirectory)\..\..\build\$(Configuration)\coverlet.msbuild.targets" />