Support parallel test runs

Tasks/RunOpenCover/Helpers.ps1

@@ -234,4 +234,63 @@ function CheckIfDirectory($filePath)
         return $true
     }
     return $false
+}
+
+function SetupRunSettingsFileForParallel {
+	[cmdletbinding()]
+	[OutputType([System.String])]
+	param(
+		[string]$runInParallelFlag,
+		[string]$runSettingsFilePath,
+		[string]$defaultCpuCount
+	)
+
+	if($runInParallelFlag -eq "True")
+	{
+		if([string]::Compare([io.path]::GetExtension($runSettingsFilePath), ".testsettings", $True) -eq 0)
+		{
+			Write-Warning "Run in Parallel is not supported with testsettings file."
+		}
+		else
+		{
+			$runSettingsForParallel = [xml]'<?xml version="1.0" encoding="utf-8"?>'
+            if([System.String]::IsNullOrWhiteSpace($runSettingsFilePath) `
+                -Or ([string]::Compare([io.path]::GetExtension($runSettingsFilePath), ".runsettings", $True) -ne 0) `
+                -Or (Test-Path $runSettingsFilePath -pathtype container))  # no file provided so create one and use it for the run
+			{
+				Write-Verbose "No runsettings file provided"
+				$runSettingsForParallel = [xml]'<?xml version="1.0" encoding="utf-8"?>
+				<RunSettings>
+				  <RunConfiguration>
+					<MaxCpuCount>0</MaxCpuCount>
+				  </RunConfiguration>
+				</RunSettings>
+				'
+			}
+			else
+			{
+				Write-Verbose "Adding maxcpucount element to runsettings file provided"
+				$runSettingsForParallel = [System.Xml.XmlDocument](Get-Content $runSettingsFilePath)
+				$runConfigurationElement = $runSettingsForParallel.SelectNodes("//RunSettings/RunConfiguration")
+				if($runConfigurationElement.Count -eq 0)
+				{
+					$runConfigurationElement = $runSettingsForParallel.RunSettings.AppendChild($runSettingsForParallel.CreateElement("RunConfiguration"))
+				}
+
+				$maxCpuCountElement = $runSettingsForParallel.SelectNodes("//RunSettings/RunConfiguration/MaxCpuCount")
+				if($maxCpuCountElement.Count -eq 0)
+				{
+					$runConfigurationElement.AppendChild($runSettingsForParallel.CreateElement("MaxCpuCount"))
+				}
+			}
+
+			$runSettingsForParallel.RunSettings.RunConfiguration.MaxCpuCount = $defaultCpuCount
+			$tempFile = [io.path]::GetTempFileName()
+			$runSettingsForParallel.Save($tempFile)
+			Write-Verbose "Temporary runsettings file created at $tempFile"
+			return $tempFile
+		}
+	}
+
+	return $runSettingsFilePath
 }

Tasks/RunOpenCover/README.md

@@ -38,6 +38,8 @@ Use the following options to select tests and control how the tests are run and
 
 - **Run Settings File:** Path to a runsettings or testsettings file can be specified here. The path can be to a file in the repository or a path to file on disk. Use $(Build.SourcesDirectory) to access the root project folder. [Click here](https://msdn.microsoft.com/library/jj635153.aspx) for more information on these files.
 
+- **Run in Parallel:** If set, tests will run in parallel leveraging available cores of the machine. [Click here](https://aka.ms/paralleltestexecution) to learn more about how tests are run in parallel.
+
 - **OpenCover Filter Criteria:** Filter what should be considered by OpenCover for code coverage. For example, "-\*[\*Tests.\*]".
 
 - **Disable OpenCover:** This allows you to only run the tests and not run OpenCover. Thus, the tasks behaves similar to to stock VSTest task from TFS / VSTS.

Tasks/RunOpenCover/RunOpenCover.ps1

@@ -170,6 +170,10 @@ try {
         # we should escape them by a backslash.
         $vsconsoleArgs = $vsconsoleArgs.Replace('"', '\"')
 
+        $openCoverReport = "$tempDir\OpenCover.xml"
+        $coberturaReport = "$tempDir\Cobertura.xml"
+        $reportDirectory = "$tempDir\CoverageReport"
+
         $openCoverConsoleArgs = "-register:user"
         if ($openCoverFilters) {
             # Only append filters, if there actually is a value. This way,
@@ -181,18 +185,14 @@ try {
         $openCoverConsoleArgs += " -target:""$vsconsoleExe"""
         $openCoverConsoleArgs += " -targetargs:""$vsconsoleArgs"""
         $openCoverConsoleArgs += " -mergeoutput"
-        $openCoverConsoleArgs += " -output:""$tempDir\OpenCover.xml"""
+        $openCoverConsoleArgs += " -output:""$openCoverReport"""
         $openCoverConsoleArgs += " -mergebyhash"
         $openCoverConsoleArgs += " -returntargetcode"
         if ($openCoverAdditionalCommandLine) {
             $openCoverConsoleArgs += " "
             $openCoverConsoleArgs += $openCoverAdditionalCommandLine
         }
 
-        $openCoverReport = "$tempDir\OpenCover.xml"
-        $coberturaReport = "$tempDir\Cobertura.xml"
-        $reportDirectory = "$tempDir\CoverageReport"
-
         $coberturaConverterArgs = "-input:""$openCoverReport"""
         $coberturaConverterArgs += " -output:""$coberturaReport"""
         $coberturaConverterArgs += " -sources:""$sourcesDirectory"""

Tasks/RunOpenCover/RunOpenCoverTask.ps1

@@ -25,6 +25,7 @@ try {
     $toolsLocationMethod = Get-VstsInput -Name toolsLocationMethod
     $toolsBaseDirectory = Get-VstsInput -Name toolsBaseDirectory
     $runSettingsFile = Get-VstsInput -Name runSettingsFile
+    $runInParallel = Get-VstsInput -Name runInParallel -AsBool
 
     Write-Verbose "SourcesDirectory: $sourcesDirectory"
     Write-Verbose "testAssembly: $testAssembly"
@@ -44,6 +45,7 @@ try {
     Write-Verbose "runSettingsFile: $runSettingsFile"
     Write-Verbose "toolsLocationMethod: $toolsLocationMethod"
     Write-Verbose "toolsBaseDirectory: $toolsBaseDirectory"
+    Write-Verbose "runInParallel: $runInParallel"
 
     if ($toolsLocationMethod -and $toolsLocationMethod -eq "location") {
         if (-Not (Test-Path $toolsBaseDirectory)) {
@@ -101,6 +103,9 @@ try {
         }
     }
 
+    $defaultCpuCount = "0"
+    $runSettingsFileWithParallel = [string](SetupRunSettingsFileForParallel $runInParallel $runSettingsFile $defaultCpuCount)
+
     . $PSScriptRoot\RunOpenCover.ps1 `
         -sourcesDirectory $sourcesDirectory `
         -testAssembly $testAssembly `
@@ -117,7 +122,7 @@ try {
         -publishRunAttachments:$publishRunAttachments `
         -taskMode `
         -toolsBaseDirectory $toolsBaseDirectory `
-        -runSettingsFile $runSettingsFile
+        -runSettingsFile $runSettingsFileWithParallel
 
 } catch {
 

Tasks/RunOpenCover/Strings/resources.resjson/en-US/resources.resjson

@@ -14,6 +14,8 @@
   "loc.input.help.testFiltercriteria": "Additional criteria to filter tests from Test assemblies. For example: Priority=1|Name=MyTestMethod",
   "loc.input.label.runSettingsFile": "Run Settings File",
   "loc.input.help.runSettingsFile": "Path to runsettings file to use with the tests. Use `$(Build.SourcesDirectory)` to access the Project folder.",
+  "loc.input.label.runInParallel": "Run In Parallel (Experimental)",
+  "loc.input.help.runInParallel": "Enable parallel execution of your tests (Experimental).",
   "loc.input.label.openCoverFilters": "OpenCover Filter criteria",
   "loc.input.help.openCoverFilters": "Additional criteria to filter what OpenCover considers.",
   "loc.input.label.disableCodeCoverage": "Disable OpenCover",

Tasks/RunOpenCover/task.json

@@ -19,7 +19,7 @@
     "version": {
         "Major": 1,
         "Minor": 0,
-        "Patch": 11
+        "Patch": 15
     },
     "minimumAgentVersion": "1.95.0",
     "instanceNameFormat": "Tests/Coverage - $(testAssembly)",
@@ -75,6 +75,15 @@
             "helpMarkDown": "Path to runsettings file to use with the tests. Use `$(Build.SourcesDirectory)` to access the Project folder.",
             "groupName": "executionOptions"
         },
+        {
+            "name": "runInParallel",
+            "type": "boolean",
+            "label": "Run In Parallel",
+            "defaultValue": "false",
+            "required": false,
+            "helpMarkDown": "Enable parallel execution of your tests.",
+            "groupName": "executionOptions"
+        },
         {
             "name": "openCoverFilters",
             "type": "string",

Tasks/RunOpenCover/task.loc.json

@@ -19,7 +19,7 @@
   "version": {
     "Major": 1,
     "Minor": 0,
-    "Patch": 11
+    "Patch": 15
   },
   "minimumAgentVersion": "1.95.0",
   "instanceNameFormat": "ms-resource:loc.instanceNameFormat",
@@ -75,6 +75,15 @@
       "helpMarkDown": "ms-resource:loc.input.help.runSettingsFile",
       "groupName": "executionOptions"
     },
+    {
+      "name": "runInParallel",
+      "type": "boolean",
+      "label": "ms-resource:loc.input.label.runInParallel",
+      "defaultValue": "false",
+      "required": false,
+      "helpMarkDown": "ms-resource:loc.input.help.runInParallel",
+      "groupName": "executionOptions"
+    },
     {
       "name": "openCoverFilters",
       "type": "string",