Add Code coverage to Azure Pipelines BVTs (#607)

Collects code coverage on the BVTs and SpinQuic.

Co-authored-by: Nick Banks <nibanks@microsoft.com>

.azure/azure-pipelines.ci.yml

@@ -187,6 +187,35 @@ stages:
       extraArgs: -Kernel
       kernel: true
 
+#
+# Code Coverage
+#
+
+- stage: codecoverage
+  displayName: Code Coverage
+  dependsOn:
+  - build_windows
+  jobs:
+  - template: ./templates/run-bvt.yml
+    parameters:
+      pool: MsQuic-Win-Latest
+      platform: windows
+      tls: schannel
+      codeCoverage: true
+  - template: ./templates/run-spinquic.yml
+    parameters:
+      pool: MsQuic-Win-Latest
+      platform: windows
+      tls: schannel
+      codeCoverage: true
+  - template: ./templates/merge-publish-coverage.yml
+    parameters:
+      image: windows-latest
+      platform: windows
+      config: Debug
+      arch: x64
+      tls: schannel
+
 #
 # SpinQuic Tests
 #

.azure/templates/merge-publish-coverage.yml

@@ -0,0 +1,48 @@
+# This template contains steps to run the BVTs for a single configuration.
+
+parameters:
+  image: ''
+  platform: ''
+  config: ''
+  arch: ''
+  tls: ''
+
+jobs:
+- job: merge_cc_${{ parameters.platform }}_${{ parameters.arch }}_${{ parameters.tls }}
+  displayName: ${{ parameters.platform }} ${{ parameters.arch }} ${{ parameters.tls }}
+  dependsOn:
+  - bvt_${{ parameters.platform }}_${{ parameters.arch }}_${{ parameters.tls }}_false_true
+  - spin_${{ parameters.platform }}_${{ parameters.arch }}_${{ parameters.tls }}
+  condition: or(succeeded(), failed())
+  pool:
+    vmImage: ${{ parameters.image }}
+  variables:
+    runCodesignValidationInjection: false
+  steps:
+  - checkout: self
+
+  - task: PowerShell@2
+    displayName: Prepare Test Machine
+    inputs:
+      pwsh: true
+      filePath: scripts/prepare-machine.ps1
+      arguments: -Configuration Test
+
+  - task: DownloadBuildArtifacts@0
+    displayName: Download Build Artifacts
+    inputs:
+      artifactName: coverage
+      itemPattern: coverage/${{ parameters.platform }}/${{ parameters.arch }}_${{ parameters.config }}_${{ parameters.tls }}/**/*.cov
+      downloadPath: artifacts
+
+  - task: Powershell@2
+    displayName: Merge coverage
+    inputs:
+      pwsh: true
+      filePath: scripts/merge-coverage.ps1
+      arguments: -Config ${{ parameters.config }} -Arch ${{ parameters.arch }} -Tls ${{ parameters.tls }}
+
+  - task: PublishCodeCoverageResults@1
+    inputs:
+      codeCoverageTool: 'cobertura'
+      summaryFileLocation: '**/artifacts/coverage/**/msquiccoverage.xml'

.azure/templates/run-bvt.yml

@@ -8,11 +8,12 @@ parameters:
   arch: 'x64'
   tls: ''
   kernel: false
+  codeCoverage: false
   logProfile: 'Basic.Light'
   extraArgs: ''
 
 jobs:
-- job: bvt_${{ parameters.platform }}_${{ parameters.arch }}_${{ parameters.tls }}_${{ parameters.kernel }}
+- job: bvt_${{ parameters.platform }}_${{ parameters.arch }}_${{ parameters.tls }}_${{ parameters.kernel }}_${{ parameters.codeCoverage }}
   displayName: ${{ parameters.platform }} ${{ parameters.arch }} ${{ parameters.tls }}
   ${{ if ne(parameters.pool, '') }}:
     pool: ${{ parameters.pool }}
@@ -51,7 +52,10 @@ jobs:
     inputs:
       pwsh: true
       filePath: scripts/test.ps1
-      arguments: -NoProgress -IsolationMode Isolated -LogProfile ${{ parameters.logProfile }} -GenerateXmlResults -Config ${{ parameters.config }} -Arch ${{ parameters.arch }} -Tls ${{ parameters.tls }} ${{ parameters.extraArgs }}
+      ${{ if eq(parameters.codeCoverage, true) }}:
+        arguments: -NoProgress -CodeCoverage -Config ${{ parameters.config }} -Arch ${{ parameters.arch }} -Tls ${{ parameters.tls }} ${{ parameters.extraArgs }}
+      ${{ if eq(parameters.codeCoverage, false) }}:
+        arguments: -NoProgress -IsolationMode Isolated -LogProfile ${{ parameters.logProfile }} -GenerateXmlResults -Config ${{ parameters.config }} -Arch ${{ parameters.arch }} -Tls ${{ parameters.tls }} ${{ parameters.extraArgs }}
 
   - template: ./upload-test-artifacts.yml
     parameters:
@@ -59,3 +63,4 @@ jobs:
       config: ${{ parameters.config }}
       arch: ${{ parameters.arch }}
       tls: ${{ parameters.tls }}
+      codeCoverage: ${{ parameters.codeCoverage }}

.azure/templates/run-spinquic.yml

@@ -7,6 +7,7 @@ parameters:
   config: 'Debug'
   arch: 'x64'
   tls: ''
+  codeCoverage: false
 
 jobs:
 - job: spin_${{ parameters.platform }}_${{ parameters.arch }}_${{ parameters.tls }}
@@ -47,7 +48,10 @@ jobs:
     inputs:
       pwsh: true
       filePath: scripts/spin.ps1
-      arguments: -GenerateXmlResults -Timeout 600000 -RepeatCount 6 -Config ${{ parameters.config }} -Arch ${{ parameters.arch }} -Tls ${{ parameters.tls }}
+      ${{ if eq(parameters.codeCoverage, true) }}:
+        arguments: -CodeCoverage -GenerateXmlResults -Timeout 600000 -RepeatCount 6 -Config ${{ parameters.config }} -Arch ${{ parameters.arch }} -Tls ${{ parameters.tls }}
+      ${{ if eq(parameters.codeCoverage, false) }}:
+        arguments: -GenerateXmlResults -Timeout 600000 -RepeatCount 6 -Config ${{ parameters.config }} -Arch ${{ parameters.arch }} -Tls ${{ parameters.tls }}
 
   - template: ./upload-test-artifacts.yml
     parameters:
@@ -55,3 +59,4 @@ jobs:
       config: ${{ parameters.config }}
       arch: ${{ parameters.arch }}
       tls: ${{ parameters.tls }}
+      codeCoverage: ${{ parameters.codeCoverage }}

.azure/templates/upload-test-artifacts.yml

@@ -5,14 +5,32 @@ parameters:
   config: ''
   arch: ''
   tls: ''
+  codeCoverage: false
 
 steps:
-  - task: CopyFiles@2
+  - ${{ if eq(parameters.codeCoverage, true) }}:
-    displayName: Stage Artifacts
+    - task: CopyFiles@2
-    inputs:
+      displayName: Stage Coverage
-      sourceFolder: artifacts/logs
+      inputs:
-      contents: '**/!(*-results.xml)'
+        sourceFolder: artifacts/coverage
-      targetFolder: $(Build.ArtifactStagingDirectory)/${{ parameters.platform }}/${{ parameters.arch }}_${{ parameters.config }}_${{ parameters.tls }}
+        contents: '**'
+        targetFolder: $(Build.ArtifactStagingDirectory)/${{ parameters.platform }}/${{ parameters.arch }}_${{ parameters.config }}_${{ parameters.tls }}
+
+  - ${{ if eq(parameters.codeCoverage, true) }}:
+    - task: PublishBuildArtifacts@1
+      displayName: Publish Coverage Output
+      inputs:
+        artifactName: coverage
+        pathToPublish: $(Build.ArtifactStagingDirectory)
+        parallel: true
+
+  - ${{ if eq(parameters.codeCoverage, false) }}:
+    - task: CopyFiles@2
+      displayName: Stage Artifacts
+      inputs:
+        sourceFolder: artifacts/logs
+        contents: '**/!(*-results.xml)'
+        targetFolder: $(Build.ArtifactStagingDirectory)/${{ parameters.platform }}/${{ parameters.arch }}_${{ parameters.config }}_${{ parameters.tls }}
 
   - task: PublishTestResults@2
     displayName: 'Publish Test Results'
@@ -21,10 +39,11 @@ steps:
       testResultsFiles: '**/*-results.xml'
       failTaskOnFailedTests: true
 
-  - task: PublishBuildArtifacts@1
+  - ${{ if eq(parameters.codeCoverage, false) }}:
-    displayName: Publish Test Output
+    - task: PublishBuildArtifacts@1
-    condition: failed()
+      displayName: Publish Test Output
-    inputs:
+      condition: failed()
-      artifactName: logs
+      inputs:
-      pathToPublish: $(Build.ArtifactStagingDirectory)
+        artifactName: logs
-      parallel: true
+        pathToPublish: $(Build.ArtifactStagingDirectory)
+        parallel: true

CMakeLists.txt

@@ -115,12 +115,12 @@ elseif ("${CMAKE_HOST_SYSTEM_NAME}" STREQUAL "Darwin")
 endif()
 
 if (QUIC_CI)
-    if (MSVC)
+    #if (MSVC)
-        file(READ ${CMAKE_CURRENT_LIST_DIR}/cmake/PdbAltPath.txt PDBALTPATH)
+    #    file(READ ${CMAKE_CURRENT_LIST_DIR}/cmake/PdbAltPath.txt PDBALTPATH)
-        set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${PDBALTPATH}")
+    #    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${PDBALTPATH}")
-        set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} ${PDBALTPATH}")
+    #    set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} ${PDBALTPATH}")
-        message(STATUS ${CMAKE_EXE_LINKER_FLAGS})
+    #    message(STATUS ${CMAKE_EXE_LINKER_FLAGS})
-    endif()
+    #endif()
 
     if (QUIC_SOURCE_LINK AND MSVC)
         if ("${CMAKE_C_COMPILER_VERSION}" VERSION_GREATER_EQUAL "19.20")

scripts/merge-coverage.ps1

@@ -0,0 +1,61 @@
+<#
+
+.SYNOPSIS
+This script merges the coverage data.
+
+.PARAMETER Config
+    Specifies the build configuration to test.
+
+.PARAMETER Arch
+    The CPU architecture to test.
+
+.PARAMETER Tls
+    The TLS library test.
+
+#>
+
+param (
+    [Parameter(Mandatory = $false)]
+    [ValidateSet("Debug", "Release")]
+    [string]$Config = "Debug",
+
+    [Parameter(Mandatory = $false)]
+    [ValidateSet("x86", "x64", "arm", "arm64")]
+    [string]$Arch = "x64",
+
+    [Parameter(Mandatory = $false)]
+    [ValidateSet("schannel", "openssl", "stub", "mitls")]
+    [string]$Tls = ""
+)
+
+Set-StrictMode -Version 'Latest'
+$PSDefaultParameterValues['*:ErrorAction'] = 'Stop'
+
+# Default TLS based on current platform.
+if ("" -eq $Tls) {
+    if ($IsWindows) {
+        $Tls = "schannel"
+    } else {
+        $Tls = "openssl"
+    }
+}
+
+# Root directory of the project.
+$RootDir = Split-Path $PSScriptRoot -Parent
+
+$CoverageDir = Join-Path $RootDir "artifacts\coverage\windows\$($Arch)_$($Config)_$($Tls)"
+
+$CoverageMergeParams = ""
+
+foreach ($file in $(Get-ChildItem -Path $CoverageDir -Filter '*.cov')) {
+    $CoverageMergeParams += " --input_coverage $(Join-Path $CoverageDir $file.Name)"
+}
+
+if ($CoverageMergeParams -ne "") {
+    $CoverageMergeParams +=  " --export_type cobertura:$(Join-Path $CoverageDir "msquiccoverage.xml")"
+
+    $CoverageExe = 'C:\"Program Files"\OpenCppCoverage\OpenCppCoverage.exe'
+    Invoke-Expression ($CoverageExe + $CoverageMergeParams) | Out-Null
+} else {
+    Write-Warning "No coverage results to merge!"
+}

scripts/prepare-machine.ps1

@@ -73,6 +73,31 @@ if ($IsWindows) {
         $ToolName = "Microsoft.Logging.CLOG2Text.Windows"
         $DownloadUrl = "https://github.com/microsoft/CLOG/releases/download/v0.1.2"
         Install-ClogTool -NuGetName $NuGetName -ToolName $ToolName -DownloadUrl $DownloadUrl
+
+        # Install OpenCppCoverage on test machines
+        if (!(Test-Path "C:\Program Files\OpenCppCoverage\OpenCppCoverage.exe")) {
+
+            Write-Host "[$(Get-Date)] Installing OpenCppCoverage..."
+
+            # Download the installer.
+            $Installer = $null
+            if ([System.Environment]::Is64BitOperatingSystem) {
+                $Installer = "OpenCppCoverageSetup-x64-0.9.9.0.exe"
+            } else {
+                $Installer = "OpenCppCoverageSetup-x86-0.9.9.0.exe"
+            }
+            $ExeFile = Join-Path $Env:TEMP $Installer
+            $ProgressPreference = 'SilentlyContinue'
+            Invoke-WebRequest -Uri "https://github.com/OpenCppCoverage/OpenCppCoverage/releases/download/release-0.9.9.0/$($Installer)" -OutFile $ExeFile
+
+            # Start the installer and wait for it to finish.
+            Start-Process $ExeFile -Wait -ArgumentList {"/silent"} -NoNewWindow
+
+            # Delete the installer.
+            Remove-Item -Path $ExeFile
+
+            Write-Host "[$(Get-Date)] OpenCppCoverage installed."
+        }
     }
 
 } else {

scripts/run-executable.ps1

@@ -36,6 +36,9 @@ This script runs an executable and collects and logs or process dumps as necessa
 .Parameter EnableAppVerifier
     Enables all basic Application Verifier checks on the executable.
 
+.Parameter CodeCoverage
+    Collect code coverage for the binary being run.
+
 #>
 
 param (
@@ -71,7 +74,10 @@ param (
     [switch]$ShowOutput = $false,
 
     [Parameter(Mandatory = $false)]
-    [switch]$EnableAppVerifier = $false
+    [switch]$EnableAppVerifier = $false,
+
+    [Parameter(Mandatory = $false)]
+    [switch]$CodeCoverage = $false
 )
 
 Set-StrictMode -Version 'Latest'
@@ -86,6 +92,19 @@ if (!(Test-Path $Path)) {
     Write-Error "$($Path) does not exist!"
 }
 
+# Validate the code coverage switch
+if ($CodeCoverage) {
+    if (!$IsWindows) {
+        Write-Error "-CodeCoverage switch only supported on Windows";
+    }
+    if ($Debugger) {
+        Write-Error "-CodeCoverage switch is not supported with debugging";
+    }
+    if (!(Test-Path "C:\Program Files\OpenCppCoverage\OpenCppCoverage.exe")) {
+        Write-Error "Code coverage tools are not installed";
+    }
+}
+
 # Root directory of the project.
 $RootDir = Split-Path $PSScriptRoot -Parent
 
@@ -94,11 +113,19 @@ $LogScript = Join-Path $RootDir "scripts" "log.ps1"
 
 # Executable name.
 $ExeName = Split-Path $Path -Leaf
+$CoverageName = "$(Split-Path $Path -LeafBase).cov"
 
 # Folder for log files.
 $LogDir = Join-Path $RootDir "artifacts" "logs" $ExeName (Get-Date -UFormat "%m.%d.%Y.%T").Replace(':','.')
 New-Item -Path $LogDir -ItemType Directory -Force | Out-Null
 
+# Folder for coverage files
+$CoverageDir = $null
+if ($CodeCoverage) {
+    $CoverageDir = Join-Path $RootDir "artifacts" "coverage"
+    New-Item -Path $CoverageDir -ItemType Directory -Force | Out-Null
+}
+
 # XML for creating a failure result data.
 $FailXmlText = @"
 <?xml version="1.0" encoding="UTF-8"?>
@@ -149,6 +176,10 @@ function Start-Executable {
             } else {
                 $pinfo.Arguments = "-g -G $($Path) $($Arguments)"
             }
+        } elseif ($CodeCoverage) {
+            $pinfo.FileName = "C:\Program Files\OpenCppCoverage\OpenCppCoverage.exe"
+            $pinfo.Arguments = "--modules=$(Split-Path $Path -Parent) --cover_children --sources src\core --sources src\inc --sources src\platform --excluded_sources unittest --working_dir $($LogDir) --export_type binary:$(Join-Path $CoverageDir $CoverageName) -- $($Path) $($Arguments)"
+            $pinfo.WorkingDirectory = $LogDir
         } else {
             $pinfo.FileName = $Path
             $pinfo.Arguments = $Arguments
@@ -266,6 +297,12 @@ function Wait-Executable($Exe) {
             }
         }
 
+        if ($CodeCoverage) {
+            # Copy coverage log
+            $LogName = "LastCoverageResults-$(Split-Path $Path -LeafBase).log"
+            Copy-Item (Join-Path $LogDir "LastCoverageResults.log") (Join-Path $CoverageDir $LogName) -Force
+        }
+
         if ($KeepOutput) {
             if ($LogProfile -ne "None") {
                 if ($ConvertLogs) {

scripts/run-gtest.ps1

@@ -53,6 +53,9 @@ as necessary.
 .Parameter EnableAppVerifier
     Enables all basic Application Verifier checks on the test binary.
 
+.Parameter CodeCoverage
+    Collects code coverage for this test run. Incompatible with -Debugger.
+
 #>
 
 param (
@@ -105,7 +108,10 @@ param (
     [switch]$NoProgress = $false,
 
     [Parameter(Mandatory = $false)]
-    [switch]$EnableAppVerifier = $false
+    [switch]$EnableAppVerifier = $false,
+
+    [Parameter(Mandatory = $false)]
+    [switch]$CodeCoverage = $false
 )
 
 Set-StrictMode -Version 'Latest'
@@ -125,6 +131,22 @@ if ($Kernel -ne "" -and !$IsWindows) {
     Write-Error "-Kernel switch only supported on Windows";
 }
 
+# Validate the code coverage switch
+if ($CodeCoverage) {
+    if (!$IsWindows) {
+        Write-Error "-CodeCoverage switch only supported on Windows";
+    }
+    if ($Debugger) {
+        Write-Error "-CodeCoverage switch is not supported with debugging";
+    }
+    if ($Kernel -ne "") {
+        Write-Error "-CodeCoverage is not supported for kernel mode tests";
+    }
+    if (!(Test-Path "C:\Program Files\OpenCppCoverage\OpenCppCoverage.exe")) {
+        Write-Error "Code coverage tools are not installed";
+    }
+}
+
 # Root directory of the project.
 $RootDir = Split-Path $PSScriptRoot -Parent
 
@@ -133,11 +155,19 @@ $LogScript = Join-Path $RootDir "scripts" "log.ps1"
 
 # Executable name.
 $TestExeName = Split-Path $Path -Leaf
+$CoverageName = "$(Split-Path $Path -LeafBase).cov"
 
 # Folder for log files.
 $LogDir = Join-Path $RootDir "artifacts" "logs" $TestExeName (Get-Date -UFormat "%m.%d.%Y.%T").Replace(':','.')
 New-Item -Path $LogDir -ItemType Directory -Force | Out-Null
 
+# Folder for coverage files
+$CoverageDir = $null
+if ($CodeCoverage) {
+    $CoverageDir = Join-Path $RootDir "artifacts" "coverage"
+    New-Item -Path $CoverageDir -ItemType Directory -Force | Out-Null
+}
+
 # The file path of the final XML results.
 $FinalResultsPath = "$($LogDir)-results.xml"
 
@@ -231,6 +261,11 @@ function Start-TestExecutable([String]$Arguments, [String]$OutputDir) {
             } else {
                 $pinfo.Arguments = "-g -G $($Path) $($Arguments)"
             }
+        } elseif ($CodeCoverage) {
+            $CoverageOutput = Join-Path $OutputDir $CoverageName
+            $pinfo.FileName = "C:\Program Files\OpenCppCoverage\OpenCppCoverage.exe"
+            $pinfo.Arguments = "--modules=$(Split-Path $Path -Parent) --cover_children --sources src\core --sources src\inc --sources src\platform --excluded_sources unittest --working_dir $($OutputDir) --export_type binary:$($CoverageOutput) -- $($Path) $($Arguments)"
+            $pinfo.WorkingDirectory = $OutputDir
         } else {
             $pinfo.FileName = $Path
             $pinfo.Arguments = $Arguments
@@ -391,6 +426,32 @@ function Wait-TestCase($TestCase) {
             Add-XmlResults $TestCase
         }
 
+        if ($CodeCoverage) {
+            $NewCoverage = Join-Path $TestCase.LogDir $Coveragename
+            if ($IsolationMode -eq "Isolated") {
+                # Merge coverage with previous runs
+                $PreviousCoverage = Join-Path $CoverageDir $CoverageName
+                if (!(Test-Path $PreviousCoverage)) {
+                    # No previous coverage data, just copy
+                    Copy-Item $NewCoverage $CoverageDir
+                } else {
+                    # Merge new coverage data with existing coverage data
+                    # On a developer machine, this will always merge coverage until the dev deletes old coverage.
+                    $TempMergedCoverage = Join-Path $CoverageDir "mergetemp.cov"
+                    $CoverageExe = 'C:\"Program Files"\OpenCppCoverage\OpenCppCoverage.exe'
+                    $CoverageMergeParams = " --input_coverage $($PreviousCoverage) --input_coverage $($NewCoverage) --export_type binary:$($TempMergedCoverage)"
+                    Invoke-Expression ($CoverageExe + $CoverageMergeParams) | Out-Null
+                    Move-Item $TempMergedCoverage $PreviousCoverage -Force
+                }
+            } else {
+                # Copy the coverage to destination
+                Copy-Item $NewCoverage $CoverageDir -Force
+                # Copy coverage log
+                $LogName = "LastCoverageResults-$(Split-Path $Path -LeafBase).log"
+                Copy-Item (Join-Path $TestCase.LogDir "LastCoverageResults.log") (Join-Path $CoverageDir $LogName) -Force
+            }
+        }
+
         if ($ProcessCrashed) {
             $AnyProcessCrashes = $true;
         }

scripts/spin.ps1

@@ -62,7 +62,10 @@ param (
 
     [Parameter(Mandatory = $false)]
     [ValidateSet("None", "Basic.Light", "Basic.Verbose", "Full.Light", "Full.Verbose", "SpinQuic.Light")]
-    [string]$LogProfile = "None"
+    [string]$LogProfile = "None",
+
+    [Parameter(Mandatory = $false)]
+    [switch]$CodeCoverage = $false
 )
 
 Set-StrictMode -Version 'Latest'
@@ -83,6 +86,19 @@ $RootDir = Split-Path $PSScriptRoot -Parent
 # Path to the run-executable Powershell script.
 $RunExecutable = Join-Path $RootDir "scripts/run-executable.ps1"
 
+#Validate the code coverage switch.
+if ($CodeCoverage) {
+    if (!$IsWindows) {
+        Write-Error "-CodeCoverage switch only supported on Windows";
+    }
+    if ($Debugger) {
+        Write-Error "-CodeCoverage switch is not supported with debugging";
+    }
+    if (!(Test-Path "C:\Program Files\OpenCppCoverage\OpenCppCoverage.exe")) {
+        Write-Error "Code coverage tools are not installed";
+    }
+}
+
 # Path to the spinquic exectuable.
 $SpinQuic = $null
 if ($IsWindows) {
@@ -110,6 +126,9 @@ if ($Debugger) {
 if ("None" -ne $LogProfile) {
     $Arguments += " -LogProfile $($LogProfile) -ConvertLogs"
 }
+if ($CodeCoverage) {
+    $Arguments += " -CodeCoverage"
+}
 
 # Run the script.
 Invoke-Expression ($RunExecutable + " " + $Arguments)

scripts/test.ps1

@@ -55,6 +55,9 @@ This script provides helpers for running executing the MsQuic tests.
 .Parameter EnableAppVerifier
     Enables all basic Application Verifier checks on test binaries.
 
+.Parameter CodeCoverage
+    Collect code coverage for this test run. Incompatible with -Kernel and -Debugger.
+
 .EXAMPLE
     test.ps1
 
@@ -131,7 +134,10 @@ param (
     [switch]$NoProgress = $false,
 
     [Parameter(Mandatory = $false)]
-    [switch]$EnableAppVerifier = $false
+    [switch]$EnableAppVerifier = $false,
+
+    [Parameter(Mandatory = $false)]
+    [switch]$CodeCoverage = $false
 )
 
 Set-StrictMode -Version 'Latest'
@@ -142,6 +148,22 @@ if ($Kernel -and !$IsWindows) {
     Write-Error "-Kernel switch only supported on Windows";
 }
 
+#Validate the code coverage switch.
+if ($CodeCoverage) {
+    if (!$IsWindows) {
+        Write-Error "-CodeCoverage switch only supported on Windows";
+    }
+    if ($Kernel) {
+        Write-Error "-CodeCoverage is not supported for kernel mode tests";
+    }
+    if ($Debugger) {
+        Write-Error "-CodeCoverage switch is not supported with debugging";
+    }
+    if (!(Test-Path "C:\Program Files\OpenCppCoverage\OpenCppCoverage.exe")) {
+        Write-Error "Code coverage tools are not installed";
+    }
+}
+
 # Default TLS based on current platform.
 if ("" -eq $Tls) {
     if ($IsWindows) {
@@ -154,6 +176,16 @@ if ("" -eq $Tls) {
 # Root directory of the project.
 $RootDir = Split-Path $PSScriptRoot -Parent
 
+# Coverage destination directory.
+$CoverageDir = Join-Path $RootDir "artifacts" "coverage"
+
+if ($CodeCoverage) {
+    # Clear old coverage data
+    if (Test-Path $CoverageDir) {
+        Remove-Item -Path (Join-Path $CoverageDir '*.cov') -Force
+    }
+}
+
 # Path to the run-gtest Powershell script.
 $RunTest = Join-Path $RootDir "scripts/run-gtest.ps1"
 
@@ -222,6 +254,9 @@ if ($NoProgress) {
 if ($EnableAppVerifier) {
     $TestArguments += " -EnableAppVerifier"
 }
+if ($CodeCoverage) {
+    $TestArguments += " -CodeCoverage"
+}
 
 # Run the script.
 if (!$Kernel) {
@@ -229,3 +264,21 @@ if (!$Kernel) {
     Invoke-Expression ($RunTest + " -Path $MsQuicPlatTest " + $TestArguments)
 }
 Invoke-Expression ($RunTest + " -Path $MsQuicTest " + $TestArguments)
+
+if ($CodeCoverage) {
+    # Merge code coverage results
+    $CoverageMergeParams = ""
+
+    foreach ($file in $(Get-ChildItem -Path $CoverageDir -Filter '*.cov')) {
+        $CoverageMergeParams += " --input_coverage $(Join-Path $CoverageDir $file.Name)"
+    }
+
+    if ($CoverageMergeParams -ne "") {
+        $CoverageMergeParams +=  " --export_type cobertura:$(Join-Path $CoverageDir "msquiccoverage.xml")"
+
+        $CoverageExe = 'C:\"Program Files"\OpenCppCoverage\OpenCppCoverage.exe'
+        Invoke-Expression ($CoverageExe + $CoverageMergeParams) | Out-Null
+    } else {
+        Write-Warning "No coverage results to merge!"
+    }
+}