feat: Add ExcludeByAttribute option (#232)

README.md

@@ -153,6 +153,12 @@ coverlet <ASSEMBLY> --target <TARGET> --targetargs <TARGETARGS> --threshold 80 -
 
 You can ignore a method or an entire class from code coverage by creating and applying the `ExcludeFromCodeCoverage` attribute present in the `System.Diagnostics.CodeAnalysis` namespace.
 
+You can also ignore additional attributes by using the `ExcludeByAttribute` property (short name or full name supported):
+
+```bash
+coverlet <ASSEMBLY> --target <TARGET> --targetargs <TARGETARGS> --exclude-by-attributes "Obsolete,GeneratedCodeAttribute,CompilerGeneratedAttribute"
+```
+
 ##### Source Files
 
 You can also ignore specific source files from code coverage using the `--exclude-by-file` option
@@ -185,7 +191,7 @@ Examples
 coverlet <ASSEMBLY> --target <TARGET> --targetargs <TARGETARGS> --exclude "[coverlet.*]Coverlet.Core.Coverage"
 ```
 
-Coverlet goes a step in the other direction by also letting you explicitly set what can be included using the `--include` option. 
+Coverlet goes a step in the other direction by also letting you explicitly set what can be included using the `--include` option.
 
 Examples
  - `--include "[*]*"` => INcludes all types in all assemblies (nothing is instrumented)
@@ -201,7 +207,7 @@ In this mode, Coverlet doesn't require any additional setup other than including
 If a property takes multiple comma-separated values please note that [you will have to add escaped quotes around the string](https://github.com/Microsoft/msbuild/issues/2999#issuecomment-366078677) like this: `/p:Exclude=\"[coverlet.*]*,[*]Coverlet.Core*\"`, `/p:Include=\"[coverlet.*]*,[*]Coverlet.Core*\"`, or `/p:CoverletOutputFormat=\"json,opencover\"`.
 
 ##### Note for Powershell / VSTS users
-To exclude or include multiple assemblies when using Powershell scripts or creating a .yaml file for a VSTS build ```%2c``` should be used as a separator. Msbuild will translate this symbol to ```,```. 
+To exclude or include multiple assemblies when using Powershell scripts or creating a .yaml file for a VSTS build ```%2c``` should be used as a separator. Msbuild will translate this symbol to ```,```.
 
 ```/p:Exclude="[*]*Examples?%2c[*]*Startup"```
 
@@ -281,6 +287,12 @@ You can specify multiple values for `ThresholdType` by separating them with comm
 
 You can ignore a method or an entire class from code coverage by creating and applying the `ExcludeFromCodeCoverage` attribute present in the `System.Diagnostics.CodeAnalysis` namespace.
 
+You can also ignore additional attributes by using the `ExcludeByAttribute` property (short name or full name supported):
+
+```bash
+dotnet test /p:CollectCoverage=true /p:ExcludeByAttribute="Obsolete,GeneratedCodeAttribute,CompilerGeneratedAttribute"
+```
+
 #### Source Files
 You can also ignore specific source files from code coverage using the `ExcludeByFile` property
  - Use single or multiple paths (separate by comma)
@@ -291,7 +303,7 @@ You can also ignore specific source files from code coverage using the `ExcludeB
 dotnet test /p:CollectCoverage=true /p:ExcludeByFile=\"../dir1/class1.cs,../dir2/*.cs,../dir3/**/*.cs,\"
 ```
 
-##### Filters 
+##### Filters
 Coverlet gives the ability to have fine grained control over what gets excluded using "filter expressions".
 
 Syntax: `/p:Exclude=[Assembly-Filter]Type-Filter`
@@ -311,7 +323,7 @@ Examples
 dotnet test /p:CollectCoverage=true /p:Exclude="[coverlet.*]Coverlet.Core.Coverage"
 ```
 
-Coverlet goes a step in the other direction by also letting you explicitly set what can be included using the `Include` property. 
+Coverlet goes a step in the other direction by also letting you explicitly set what can be included using the `Include` property.
 
 Examples
  - `/p:Include="[*]*"` => Includes all types in all assemblies (everything is instrumented)

src/coverlet.console/Program.cs

@@ -35,6 +35,7 @@ static int Main(string[] args)
             CommandOption includeFilters = app.Option("--include", "Filter expressions to include only specific modules and types.", CommandOptionType.MultipleValue);
             CommandOption excludedSourceFiles = app.Option("--exclude-by-file", "Glob patterns specifying source files to exclude.", CommandOptionType.MultipleValue);
             CommandOption mergeWith = app.Option("--merge-with", "Path to existing coverage result to merge.", CommandOptionType.SingleValue);
+            CommandOption excludeAttributes = app.Option("--exclude-by-attribute", "Attributes to exclude from code coverage.", CommandOptionType.MultipleValue);
 
             app.OnExecute(() =>
             {
@@ -44,7 +45,7 @@ static int Main(string[] args)
                 if (!target.HasValue())
                     throw new CommandParsingException(app, "Target must be specified.");
 
-                Coverage coverage = new Coverage(module.Value, excludeFilters.Values.ToArray(), includeFilters.Values.ToArray(), excludedSourceFiles.Values.ToArray(), mergeWith.Value());
+                Coverage coverage = new Coverage(module.Value, excludeFilters.Values.ToArray(), includeFilters.Values.ToArray(), excludedSourceFiles.Values.ToArray(), mergeWith.Value(), excludeAttributes.Values.ToArray());
                 coverage.PrepareModules();
 
                 Process process = new Process();

src/coverlet.core/Coverage.cs

@@ -19,20 +19,22 @@ public class Coverage
         private string[] _includeFilters;
         private string[] _excludedSourceFiles;
         private string _mergeWith;
+        private string[] _excludeAttributes;
         private List<InstrumenterResult> _results;
 
         public string Identifier
         {
             get { return _identifier; }
         }
 
-        public Coverage(string module, string[] excludeFilters, string[] includeFilters, string[] excludedSourceFiles, string mergeWith)
+        public Coverage(string module, string[] excludeFilters, string[] includeFilters, string[] excludedSourceFiles, string mergeWith, string[] excludeAttributes)
         {
             _module = module;
             _excludeFilters = excludeFilters;
             _includeFilters = includeFilters;
             _excludedSourceFiles = excludedSourceFiles;
             _mergeWith = mergeWith;
+            _excludeAttributes = excludeAttributes;
 
             _identifier = Guid.NewGuid().ToString();
             _results = new List<InstrumenterResult>();
@@ -51,7 +53,7 @@ public void PrepareModules()
                     || !InstrumentationHelper.IsModuleIncluded(module, _includeFilters))
                     continue;
 
-                var instrumenter = new Instrumenter(module, _identifier, _excludeFilters, _includeFilters, excludes);
+                var instrumenter = new Instrumenter(module, _identifier, _excludeFilters, _includeFilters, excludes, _excludeAttributes);
                 if (instrumenter.CanInstrument())
                 {
                     InstrumentationHelper.BackupOriginalModule(module, _identifier);

src/coverlet.core/Instrumentation/Instrumenter.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Diagnostics;
 using System.Diagnostics.CodeAnalysis;
 using System.IO;
@@ -22,20 +23,22 @@ internal class Instrumenter
         private readonly string[] _excludeFilters;
         private readonly string[] _includeFilters;
         private readonly string[] _excludedFiles;
+        private readonly string[] _excludedAttributes;
         private InstrumenterResult _result;
         private FieldDefinition _customTrackerHitsArray;
         private FieldDefinition _customTrackerHitsFilePath;
         private ILProcessor _customTrackerClassConstructorIl;
         private TypeDefinition _customTrackerTypeDef;
         private MethodReference _customTrackerRecordHitMethod;
 
-        public Instrumenter(string module, string identifier, string[] excludeFilters, string[] includeFilters, string[] excludedFiles)
+        public Instrumenter(string module, string identifier, string[] excludeFilters, string[] includeFilters, string[] excludedFiles, string[] excludedAttributes)
         {
             _module = module;
             _identifier = identifier;
             _excludeFilters = excludeFilters;
             _includeFilters = includeFilters;
             _excludedFiles = excludedFiles ?? Array.Empty<string>();
+            _excludedAttributes = excludedAttributes;
         }
 
         public bool CanInstrument() => InstrumentationHelper.HasPdb(_module);
@@ -179,7 +182,7 @@ private void AddCustomModuleTrackerToModule(ModuleDefinition module)
                         {
                             handler.CatchType = module.ImportReference(handler.CatchType);
                         }
-                        
+
                         methodOnCustomType.Body.ExceptionHandlers.Add(handler);
                     }
 
@@ -392,19 +395,24 @@ private static void ReplaceExceptionHandlerBoundary(ExceptionHandler handler, In
                 handler.TryStart = newTarget;
         }
 
-        private static bool IsExcludeAttribute(CustomAttribute customAttribute)
+        private bool IsExcludeAttribute(CustomAttribute customAttribute)
         {
-            var excludeAttributeNames = new[]
+            // The default custom attributes used to exclude from coverage.
+            IEnumerable<string> excludeAttributeNames = new List<string>()
             {
                 nameof(ExcludeFromCoverageAttribute),
-                "ExcludeFromCoverage",
-                nameof(ExcludeFromCodeCoverageAttribute),
-                "ExcludeFromCodeCoverage"
+                nameof(ExcludeFromCodeCoverageAttribute)
             };
 
-            var attributeName = customAttribute.AttributeType.Name;
-            return excludeAttributeNames.Any(a => a.Equals(attributeName));
-        }
+            // Include the other attributes to exclude based on incoming parameters.
+            if (_excludedAttributes != null)
+            {
+                excludeAttributeNames = _excludedAttributes.Union(excludeAttributeNames);
+            }
+
+			return excludeAttributeNames.Any(a =>
+                customAttribute.AttributeType.Name.Equals(a.EndsWith("Attribute")? a : $"{a}Attribute"));
+		}
 
         private static Mono.Cecil.Cil.MethodBody GetMethodBody(MethodDefinition method)
         {

src/coverlet.msbuild.tasks/InstrumentationTask.cs

@@ -13,6 +13,7 @@ public class InstrumentationTask : Task
         private string _include;
         private string _excludeByFile;
         private string _mergeWith;
+        private string _excludeByAttributes;
 
         internal static Coverage Coverage
         {
@@ -25,7 +26,7 @@ public string Path
             get { return _path; }
             set { _path = value; }
         }
-        
+
         public string Exclude
         {
             get { return _exclude; }
@@ -50,15 +51,22 @@ public string MergeWith
             set { _mergeWith = value; }
         }
 
+        public string ExcludeByAttributes
+        {
+            get { return _excludeByAttributes; }
+            set { _excludeByAttributes = value; }
+        }
+
         public override bool Execute()
         {
             try
             {
                 var excludedSourceFiles = _excludeByFile?.Split(',');
                 var excludeFilters = _exclude?.Split(',');
                 var includeFilters = _include?.Split(',');
+                var excludeAttributes = _excludeByAttributes?.Split(',');
 
-                _coverage = new Coverage(_path, excludeFilters, includeFilters, excludedSourceFiles, _mergeWith);
+                _coverage = new Coverage(_path, excludeFilters, includeFilters, excludedSourceFiles, _mergeWith, excludeAttributes);
                 _coverage.PrepareModules();
             }
             catch (Exception ex)

src/coverlet.msbuild/coverlet.msbuild.props

@@ -9,5 +9,6 @@
     <MergeWith Condition="$(MergeWith) == ''"></MergeWith>
     <Threshold Condition="$(Threshold) == ''">0</Threshold>
     <ThresholdType Condition="$(ThresholdType) == ''">line,branch,method</ThresholdType>
+    <ExcludeByAttributes Condition="$(ExcludeByAttributes) == ''"></ExcludeByAttributes>
   </PropertyGroup>
 </Project>

src/coverlet.msbuild/coverlet.msbuild.targets

@@ -10,6 +10,7 @@
       Exclude="$(Exclude)"
       ExcludeByFile="$(ExcludeByFile)"
       MergeWith="$(MergeWith)"
+      ExcludeByAttributes="$(ExcludeByAttributes)"
       Path="$(TargetPath)" />
   </Target>
 
@@ -20,6 +21,7 @@
       Exclude="$(Exclude)"
       ExcludeByFile="$(ExcludeByFile)"
       MergeWith="$(MergeWith)"
+      ExcludeByAttributes="$(ExcludeByAttributes)"
       Path="$(TargetPath)" />
   </Target>
 

test/coverlet.core.tests/CoverageTests.cs

@@ -27,7 +27,7 @@ public void TestCoverage()
             // Since Coverage only instruments dependancies, we need a fake module here
             var testModule = Path.Combine(directory.FullName, "test.module.dll");
 
-            var coverage = new Coverage(testModule, Array.Empty<string>(), Array.Empty<string>(), Array.Empty<string>(), string.Empty);
+            var coverage = new Coverage(testModule, Array.Empty<string>(), Array.Empty<string>(), Array.Empty<string>(), string.Empty, Array.Empty<string>());
             coverage.PrepareModules();
 
             var result = coverage.GetCoverageResult();

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

@@ -27,7 +27,7 @@ public void TestCoreLibInstrumentation()
             foreach (var file in files)
                 File.Copy(Path.Combine(OriginalFilesDir, file), Path.Combine(TestFilesDir, file), overwrite: true);
 
-            Instrumenter instrumenter = new Instrumenter(Path.Combine(TestFilesDir, files[0]), "_coverlet_instrumented", Array.Empty<string>(), Array.Empty<string>(), Array.Empty<string>());
+            Instrumenter instrumenter = new Instrumenter(Path.Combine(TestFilesDir, files[0]), "_coverlet_instrumented", Array.Empty<string>(), Array.Empty<string>(), Array.Empty<string>(), Array.Empty<string>());
             Assert.True(instrumenter.CanInstrument());
             var result = instrumenter.Instrument();
             Assert.NotNull(result);
@@ -76,7 +76,26 @@ public void TestInstrument_ClassesWithExcludeAttributeAreExcluded(Type excludedT
             instrumenterTest.Directory.Delete(true);
         }
 
-        private InstrumenterTest CreateInstrumentor(bool fakeCoreLibModule = false)
+
+        [Theory]
+        [InlineData(nameof(ObsoleteAttribute))]
+        [InlineData("Obsolete")]
+        public void TestInstrument_ClassesWithCustomExcludeAttributeAreExcluded(string excludedAttribute)
+        {
+            var instrumenterTest = CreateInstrumentor(attributesToIgnore: new string[] { excludedAttribute });
+            var result = instrumenterTest.Instrumenter.Instrument();
+
+            var doc = result.Documents.Values.FirstOrDefault(d => Path.GetFileName(d.Path) == "Samples.cs");
+            Assert.NotNull(doc);
+#pragma warning disable CS0612 // Type or member is obsolete
+            var found = doc.Lines.Values.Any(l => l.Class.Equals(nameof(ClassExcludedByObsoleteAttr)));
+#pragma warning restore CS0612 // Type or member is obsolete
+            Assert.False(found, "Class decorated with with exclude attribute should be excluded");
+
+            instrumenterTest.Directory.Delete(true);
+        }
+
+        private InstrumenterTest CreateInstrumentor(bool fakeCoreLibModule = false, string[] attributesToIgnore = null)
         {
             string module = GetType().Assembly.Location;
             string pdb = Path.Combine(Path.GetDirectoryName(module), Path.GetFileNameWithoutExtension(module) + ".pdb");
@@ -100,7 +119,7 @@ private InstrumenterTest CreateInstrumentor(bool fakeCoreLibModule = false)
             File.Copy(pdb, Path.Combine(directory.FullName, destPdb), true);
 
             module = Path.Combine(directory.FullName, destModule);
-            Instrumenter instrumenter = new Instrumenter(module, identifier, Array.Empty<string>(), Array.Empty<string>(), Array.Empty<string>());
+            Instrumenter instrumenter = new Instrumenter(module, identifier, Array.Empty<string>(), Array.Empty<string>(), Array.Empty<string>(), attributesToIgnore);
             return new InstrumenterTest
             {
                 Instrumenter = instrumenter,

test/coverlet.core.tests/Samples/Samples.cs

@@ -189,4 +189,17 @@ public string Method(string input)
             return input;
         }
     }
+
+    [Obsolete]
+    public class ClassExcludedByObsoleteAttr
+    {
+
+        public string Method(string input)
+        {
+            if (string.IsNullOrEmpty(input))
+                throw new ArgumentException("Cannot be empty", nameof(input));
+
+            return input;
+        }
+    }
 }