Enforce minimum code coverage threshold in CI pipeline

eng/pipelines/release-cli.yml

@@ -125,6 +125,7 @@ extends:
 
     - template: /eng/pipelines/templates/stages/code-coverage-upload.yml
       parameters:
+        MinimumCoveragePercent: 80
         DownloadArtifacts:
           - cover-win
           - cover-lin

eng/pipelines/templates/stages/code-coverage-upload.yml

@@ -5,6 +5,9 @@ parameters:
       - cover-win
       - cover-lin
       - cover-mac
+  - name: MinimumCoveragePercent
+    type: number
+    default: 0
 stages: 
 - stage: CodeCoverage_Upload
   condition: and(succeeded(), ne(variables['Skip.LiveTest'], 'true'))
@@ -59,6 +62,11 @@ stages:
           }
         displayName: Merge code coverage files
 
+      - ${{ if gt(parameters.MinimumCoveragePercent, 0) }}:
+        - pwsh: |
+            pwsh -File "$(Build.SourcesDirectory)/eng/scripts/Test-CodeCoverageThreshold.ps1" -CoverageFile cover.out -MinimumCoveragePercent ${{ parameters.MinimumCoveragePercent }}
+          displayName: Check code coverage threshold
+
       - task: PublishCodeCoverageResults@1
         inputs:
           codeCoverageTool: Cobertura

eng/scripts/Test-CodeCoverageThreshold.ps1

@@ -0,0 +1,62 @@
+#!/usr/bin/env pwsh
+
+<#
+.SYNOPSIS
+    Checks that code coverage meets a minimum threshold.
+
+.DESCRIPTION
+    Parses a Go coverage profile using 'go tool cover -func' to extract the
+    total statement coverage percentage, then fails if it is below the
+    specified minimum.
+
+.PARAMETER CoverageFile
+    Path to the Go coverage profile (typically cover.out).
+
+.PARAMETER MinimumCoveragePercent
+    The minimum acceptable coverage percentage (0-100). The script exits
+    with a non-zero code when coverage is below this value.
+
+.EXAMPLE
+    ./Test-CodeCoverageThreshold.ps1 -CoverageFile cover.out -MinimumCoveragePercent 48
+#>
+
+param(
+    [Parameter(Mandatory = $true)]
+    [string]$CoverageFile,
+
+    [Parameter(Mandatory = $true)]
+    [double]$MinimumCoveragePercent
+)
+
+$ErrorActionPreference = 'Stop'
+
+if (-not (Test-Path $CoverageFile)) {
+    throw "Coverage file '$CoverageFile' not found"
+}
+
+Write-Host "Checking code coverage threshold (minimum: $MinimumCoveragePercent%)..."
+
+# Use 'go tool cover -func' to get per-function coverage and the total line.
+$output = & go tool cover -func=$CoverageFile 2>&1
+if ($LASTEXITCODE -ne 0) {
+    throw "go tool cover -func failed: $output"
+}
+
+# The last line looks like: "total:    (statements)   48.3%"
+$lastLine = ($output | Select-Object -Last 1).ToString()
+
+if ($lastLine -match '(\d+\.\d+)%') {
+    $coveragePercent = [double]$matches[1]
+} else {
+    throw "Could not parse total coverage from 'go tool cover -func' output: $lastLine"
+}
+
+Write-Host "Total statement coverage: $coveragePercent%"
+
+if ($coveragePercent -lt $MinimumCoveragePercent) {
+    Write-Host "##vso[task.logissue type=error]Code coverage $coveragePercent% is below the minimum threshold of $MinimumCoveragePercent%."
+    Write-Host "##vso[task.complete result=Failed;]Coverage threshold not met."
+    exit 1
+}
+
+Write-Host "Coverage $coveragePercent% meets the minimum threshold of $MinimumCoveragePercent%. ✓"