fix: Report real code coverage percentages in Test-PSBuildPester

CHANGELOG.md

@@ -62,7 +62,7 @@
  that passed before may now correctly fail.
 - [**#96**](https://github.com/psake/PowerShellBuild/issues/96)
  `Test-PSBuildScriptAnalysis` no longer fails with a path-resolution error
  when `SettingsPath` is not supplied. An unsupplied path was forwarded to
  PSScriptAnalyzer as `-Settings ''`, which resolved against the current
  directory and threw before any analysis ran, so the function's own
  documented example could not run as written.
@@ -76,6 +76,15 @@
  two Pester versions were installed side by side. When no Pester is loaded,
  the newest installed version (5.0.0 minimum) is imported as before, and a
  loaded Pester older than 5.0.0 now produces a clear error.
+- [**#138**](https://github.com/psake/PowerShellBuild/issues/138)
+ `Test-PSBuildPester` now reports real code coverage percentages and compares
+ them against `CodeCoverageThreshold` correctly. Each percentage was passed
+ through `[Math]::Truncate`, which collapses any fraction to zero, so the
+ coverage report always printed `0.00%` (or `100.00%`) and every threshold
+ above zero failed the build unless coverage was exactly 100%. Consumers who
+ set `$PSBPreference.Test.CodeCoverage.Threshold` could not use coverage
+ gating at all. The comparison is now strictly more permissive than before,
+ so a build that passed with a coverage threshold set still passes.
 
 ## [0.8.2] 2026-07-08
 

PowerShellBuild/Public/Test-PSBuildPester.ps1

@@ -124,7 +124,12 @@ function Test-PSBuildPester {
  [xml]$testCoverage = Get-Content $CodeCoverageOutputFile
  $ccReport = $testCoverage.report.counter.ForEach({
  $total = [int]$_.missed + [int]$_.covered
- $percent = [Math]::Truncate([int]$_.covered / $total)
+ # Keep the ratio as a fraction between 0 and 1. [Math]::Truncate collapsed
+ # every partial result to 0, which both printed 0.00% and failed the
+ # CodeCoverageThreshold comparison below for any coverage under 100%.
+ # The value is deliberately not rounded: rounding 0.7996 up to 0.80 would
+ # pass a 0.80 threshold that the real coverage does not meet.
+ $percent = [int]$_.covered / $total
  [PSCustomObject]@{
  name = $textInfo.ToTitleCase($_.Type.ToLower())
  percent = $percent

tests/Test-PSBuildPester.tests.ps1

@@ -61,8 +61,12 @@
 
  $threw = $false
  $errorMessage = $null
+ # Capture the command's output rather than letting it fall through to the job's
+ # output stream, where the coverage report lines would be interleaved with the
+ # result object below.
+ $commandOutput = @()
  try {
- Test-PSBuildPester @testPSBuildPesterParameters
+$commandOutput = @(Test-PSBuildPester @testPSBuildPesterParameters)
  } catch {
  $threw = $true
  $errorMessage = $_.Exception.Message
@@ -71,6 +75,7 @@
  [PSCustomObject]@{
  Threw = $threw
  ErrorMessage = $errorMessage
+ Output = $commandOutput
  LoadedPesterVersions = @((Get-Module -Name 'Pester').Version.ToString())
  }
  } -ArgumentList $InnerPesterVersion, $script:builtModulePath, $Path, $AdditionalParameters
@@ -82,9 +87,9 @@
 
  # Scenario directories, generated at runtime.
  $script:healthyPath = Join-Path -Path $TestDrive -ChildPath 'healthy'
  $script:failingTestPath = Join-Path -Path $TestDrive -ChildPath 'failingtest'
  $script:beforeAllCrashPath = Join-Path -Path $TestDrive -ChildPath 'beforeallcrash'
  $script:discoveryCrashPath = Join-Path -Path $TestDrive -ChildPath 'discoverycrash'
  $script:coveragePath = Join-Path -Path $TestDrive -ChildPath 'coverage'
  $script:outputPath = Join-Path -Path $TestDrive -ChildPath 'out'
  foreach ($directory in @(
@@ -220,6 +225,39 @@
  [xml]$coverageReport = Get-Content -Path $coverageOutputPath -Raw
  $coverageReport.report | Should -Not -BeNullOrEmpty
  }
+
+ # The coverage scenario exercises only Get-Widget while measuring both public fixture
+ # functions, so measured coverage is always partial: comfortably above 1% and well
+ # below 99%. Asserting from both sides pins the reported value to a fraction between
+ # 0 and 1 -- a truncated 0 fails the first test, and a 0-to-100 scale fails the second.
+ It 'passes when measured coverage is above the code coverage threshold' {
+ # Regression: #138
+ $coverageOutputPath = Join-Path -Path $script:outputPath -ChildPath "coverage-above-threshold-$script:innerVersion.xml"
+ $additionalParameters = @{
+ CodeCoverage = $true
+ CodeCoverageFiles = @(Join-Path -Path $script:fixturePath -ChildPath 'Public/*.ps1')
+ CodeCoverageOutputFile = $coverageOutputPath
+ CodeCoverageThreshold = 0.01
+ }
+ $result = Invoke-TestPSBuildPesterJob -InnerPesterVersion $script:innerVersion -Path $script:coveragePath -AdditionalParameters $additionalParameters
+
+ $result.Threw | Should -BeFalse
+ }
+
+ It 'fails when measured coverage is below the code coverage threshold' {
+ # Regression: #138
+ $coverageOutputPath = Join-Path -Path $script:outputPath -ChildPath "coverage-below-threshold-$script:innerVersion.xml"
+ $additionalParameters = @{
+ CodeCoverage = $true
+ CodeCoverageFiles = @(Join-Path -Path $script:fixturePath -ChildPath 'Public/*.ps1')
+ CodeCoverageOutputFile = $coverageOutputPath
+ CodeCoverageThreshold = 0.99
+ }
+ $result = Invoke-TestPSBuildPesterJob -InnerPesterVersion $script:innerVersion -Path $script:coveragePath -AdditionalParameters $additionalParameters
+
+ $result.Threw | Should -BeTrue
+ $result.ErrorMessage | Should -Match 'less than the threshold'
+ }
  }
 
  # BeforeDiscovery variables are not visible during the run phase, so the discovered version