OPS-157454: Upload test coverage to Codacy from CI

.github/workflows/ci.yml

@@ -39,6 +39,68 @@ jobs:
         name: packages
         path: ./artifacts/*.nupkg
 
+  # Test coverage, uploaded to Codacy (OPS-157454).
+  # pdl-public, never a GitHub-hosted runner and never pdl-prod-cluster: this repository is public,
+  # so a fork pull request is untrusted code, and pdl-public is the hardened scale set that may run
+  # it (no dind, no privileged container, no hostPath, nothing shared between jobs).
+  coverage:
+    runs-on: [pdl-public]
+
+    env:
+      DOTNET_NOLOGO: 1
+      DOTNET_CLI_TELEMETRY_OPTOUT: 1
+      # The actions-runner image does not offer the Node version several of these actions request
+      # by default; without this they fail before their first step runs.
+      FORCE_JAVASCRIPT_ACTIONS_TO_NODE24: true
+
+    steps:
+    - uses: actions/checkout@v7
+      with:
+        fetch-depth: 0 # avoid shallow clone so nbgv can do its work.
+
+    - name: Setup .NET
+      uses: actions/setup-dotnet@v6
+      # The runner user cannot write /usr/share/dotnet, so install the SDK somewhere it can.
+      env:
+        DOTNET_INSTALL_DIR: ${{ runner.temp }}/dotnet
+      with:
+        dotnet-version: 10.0.x
+
+    - name: Build tests
+      run: dotnet build PanoramicData.ChartMagic.Test/PanoramicData.ChartMagic.Test.csproj --configuration Debug
+
+    # The test project is a Microsoft.Testing.Platform application, so coverage is collected by
+    # running the test executable directly (Microsoft.Testing.Extensions.CodeCoverage) rather than
+    # through `dotnet test`. On Linux the executable has no .exe extension.
+    #
+    # Every test in this repository runs offline with no credentials, so no filter is applied.
+    - name: Run tests with coverage
+      run: >-
+        ./PanoramicData.ChartMagic.Test/bin/Debug/net10.0/PanoramicData.ChartMagic.Test
+        --coverage
+        --coverage-settings "$GITHUB_WORKSPACE/coverage.config"
+        --coverage-output-format cobertura
+        --coverage-output coverage.cobertura.xml
+
+    # continue-on-error: a Codacy outage must not turn a passing test run red. The trade-off is that
+    # an expired or missing project token fails silently, so check the log for
+    # "Coverage received successfully" when in doubt.
+    - name: Upload coverage to Codacy
+      continue-on-error: true
+      uses: codacy/codacy-coverage-reporter-action@v1
+      with:
+        project-token: ${{ secrets.CODACY_PROJECT_TOKEN }}
+        coverage-reports: PanoramicData.ChartMagic.Test/bin/Debug/net10.0/TestResults/coverage.cobertura.xml
+
+    - name: Upload coverage artifact
+      if: always()
+      continue-on-error: true
+      uses: actions/upload-artifact@v7
+      with:
+        name: coverage
+        path: PanoramicData.ChartMagic.Test/bin/Debug/net10.0/TestResults/coverage.cobertura.xml
+        retention-days: 7
+
   publish:
     needs: build
     runs-on: ubuntu-latest

PanoramicData.ChartMagic.Test/PanoramicData.ChartMagic.Test.csproj

@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFramework>net10.0</TargetFramework>
+    <UseMicrosoftTestingPlatformRunner>true</UseMicrosoftTestingPlatformRunner>
     <IsPackable>false</IsPackable>
     <LangVersion>latest</LangVersion>
     <AnalysisLevel>latest-recommended</AnalysisLevel>

coverage.config

@@ -0,0 +1,33 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  Microsoft.Testing.Extensions.CodeCoverage settings.
+
+  The attribute exclusions are not optional if figures are to stay comparable across the estate: the
+  Microsoft collector includes generated code by default, where coverlet excluded it. Porting them is
+  worth several points of apparent coverage on a repository with generated clients.
+-->
+<Configuration>
+  <CodeCoverage>
+    <ModulePaths>
+      <Exclude>
+        <ModulePath>.*Test\.dll$</ModulePath>
+        <ModulePath>.*Tests\.dll$</ModulePath>
+      </Exclude>
+    </ModulePaths>
+    <Attributes>
+      <Exclude>
+        <Attribute>^System\.Diagnostics\.CodeAnalysis\.ExcludeFromCodeCoverageAttribute$</Attribute>
+        <Attribute>^System\.Runtime\.CompilerServices\.CompilerGeneratedAttribute$</Attribute>
+        <Attribute>^System\.CodeDom\.Compiler\.GeneratedCodeAttribute$</Attribute>
+        <Attribute>^System\.ObsoleteAttribute$</Attribute>
+      </Exclude>
+    </Attributes>
+    <Sources>
+      <Exclude>
+        <Source>.*\\obj\\.*</Source>
+      </Exclude>
+    </Sources>
+    <UseVerifiableInstrumentation>False</UseVerifiableInstrumentation>
+    <CollectFromChildProcesses>True</CollectFromChildProcesses>
+  </CodeCoverage>
+</Configuration>