Support .NET Framework(>= net461) for in-process data collectors (#970)

Support .NET Framework(>= net461) for in-process data collectors

Documentation/Troubleshooting.md

@@ -244,4 +244,9 @@ You can live attach and debug collectors with `COVERLET_DATACOLLECTOR_OUTOFPROC_
  set COVERLET_DATACOLLECTOR_OUTOFPROC_DEBUG=1
  set COVERLET_DATACOLLECTOR_INPROC_DEBUG=1
 ```
-You will be asked to attach a debugger through UI popup.
+You will be asked to attach a debugger through UI popup.  
+To enable exceptions log for in-process data collectors
+```
+ set COVERLET_DATACOLLECTOR_INPROC_EXCEPTIONLOG_ENABLED=1
+```
+

Documentation/VSTestIntegration.md

@@ -1,6 +1,14 @@
 # Coverlet integration with VSTest (a.k.a. Visual Studio Test Platform)
 
-**At the moment collectors integration supports only .NET Core applications and not .NET Framework ones.**
+**Supported runtime versions:**  
+Before version `3.0.0`  
+- .NET Core >= 2.0 
+- .NET Framework not fully supported(only out of process collector, could suffer of [known issue](https://github.com/coverlet-coverage/coverlet/blob/master/Documentation/KnownIssues.md#1-vstest-stops-process-execution-earlydotnet-test))  
+
+Since version `3.0.0` 
+- .NET Core >= 2.0 
+- .NET Framework >= 4.6.1  
+
 
 As explained in quick start section to use collectors you need to run *SDK v2.2.401* or newer and your project file must reference `coverlet.collector.dll` and a minimum version of `Microsoft.NET.Test.Sdk`.  
 A sample project file looks like:

src/coverlet.collector/DataCollection/CoverletSettingsParser.cs

@@ -237,7 +237,7 @@ namespace Coverlet.Collector.DataCollection
         /// <returns>An array of the values in the element</returns>
         private string[] SplitElement(XmlElement element)
         {
-            return element?.InnerText?.Split(',', StringSplitOptions.RemoveEmptyEntries).Where(value => !string.IsNullOrWhiteSpace(value)).Select(value => value.Trim()).ToArray();
+            return element?.InnerText?.Split(new char[] { ',' }, StringSplitOptions.RemoveEmptyEntries).Where(value => !string.IsNullOrWhiteSpace(value)).Select(value => value.Trim()).ToArray();
         }
     }
 }

src/coverlet.collector/InProcDataCollection/CoverletInProcDataCollector.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Diagnostics;
 using System.Reflection;
+using System.Text;
 
 using coverlet.collector.Resources;
 using Coverlet.Collector.Utilities;
@@ -14,6 +15,7 @@ namespace Coverlet.Collector.DataCollection
     public class CoverletInProcDataCollector : InProcDataCollection
     {
         private TestPlatformEqtTrace _eqtTrace;
+        private bool _enableExceptionLog = false;
 
         private void AttachDebugger()
         {
@@ -24,10 +26,18 @@ namespace Coverlet.Collector.DataCollection
             }
         }
 
+        private void EnableExceptionLog()
+        {
+            if (int.TryParse(Environment.GetEnvironmentVariable("COVERLET_DATACOLLECTOR_INPROC_EXCEPTIONLOG_ENABLED"), out int result) && result == 1)
+            {
+                _enableExceptionLog = true;
+            }
+        }
+
         public void Initialize(IDataCollectionSink dataCollectionSink)
         {
-
             AttachDebugger();
+            EnableExceptionLog();
 
             _eqtTrace = new TestPlatformEqtTrace();
             _eqtTrace.Verbose("Initialize CoverletInProcDataCollector");
@@ -61,9 +71,12 @@ namespace Coverlet.Collector.DataCollection
                 }
                 catch (Exception ex)
                 {
-                    _eqtTrace.Error("{0}: Failed to unload module with error: {1}", CoverletConstants.InProcDataCollectorName, ex);
-                    string errorMessage = string.Format(Resources.FailedToUnloadModule, CoverletConstants.InProcDataCollectorName);
-                    throw new CoverletDataCollectorException(errorMessage, ex);
+                    if (_enableExceptionLog)
+                    {
+                        _eqtTrace.Error("{0}: Failed to unload module with error: {1}", CoverletConstants.InProcDataCollectorName, ex);
+                        string errorMessage = string.Format(Resources.FailedToUnloadModule, CoverletConstants.InProcDataCollectorName);
+                        throw new CoverletDataCollectorException(errorMessage, ex);
+                    }
                 }
             }
         }
@@ -89,7 +102,25 @@ namespace Coverlet.Collector.DataCollection
             }
             catch (Exception ex)
             {
-                _eqtTrace.Warning("{0}: Failed to get Instrumentation class with error: {1}", CoverletConstants.InProcDataCollectorName, ex);
+                if (_enableExceptionLog)
+                {
+                    StringBuilder exceptionString = new StringBuilder();
+                    exceptionString.AppendFormat("{0}: Failed to get Instrumentation class for assembly '{1}' with error: {2}",
+                        CoverletConstants.InProcDataCollectorName, assembly, ex);
+                    exceptionString.AppendLine();
+
+                    if (ex is ReflectionTypeLoadException rtle)
+                    {
+                        exceptionString.AppendLine("ReflectionTypeLoadException list:");
+                        foreach (Exception loaderEx in rtle.LoaderExceptions)
+                        {
+                            exceptionString.AppendLine(loaderEx.ToString());
+                        }
+                    }
+
+                    _eqtTrace.Warning(exceptionString.ToString());
+                }
+
                 return null;
             }
         }

src/coverlet.collector/coverlet.collector.csproj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFramework>netcoreapp2.0</TargetFramework>
+    <TargetFramework>netstandard2.0</TargetFramework>
     <AssemblyTitle>coverlet.collector</AssemblyTitle>
     <DevelopmentDependency>true</DevelopmentDependency>
     <CopyLocalLockFileAssemblies>true</CopyLocalLockFileAssemblies>