Code coverage always 100% during pipeline execution

Hi ​@g.davico ,

In Cloud Manager, coverage comes from JaCoCo -> SonarQube -> “Coverage” metric in the Code Quality step, not directly from your local JaCoCo HTML. If SonarQube sees no (or almost no) Java “lines to cover”, it reports 100% coverage by definition, and Cloud Manager just surfaces that value. This is documented behavior for projects without Java code: such projects report 100% coverage even though nothing is really being measured (https://experienceleague.adobe.com/en/docs/experience-manager-cloud-manager/content/release-notes/rn-2019/2019-12-0) and coverage definition in (https://experienceleague.adobe.com/en/docs/experience-manager-cloud-manager/content/using/code-quality-testing)

So if all your pipelines show 100% but local JaCoCo is lower, the problem is almost always:
Your real Java code isn’t in the coverage scope of the Cloud Manager SonarQube analysis.

Typical reasons:

• The modules Cloud Manager actually analyzes have no Java code (only content/dispatcher/etc.).
• A custom jacoco-maven-plugin config excludes or restricts your main code via includes / excludes.
• A Cloud-Manager‑only Maven profile changes what’s built or how JaCoCo runs.

Quick checks:

• Check the Code Quality CSV from Cloud Manager
  • Open the last pipeline -> Code Quality -> Download details (CSV).
  • Look at lines_to_cover / uncovered_lines.
  • If they’re 0 everywhere, CM thinks there’s nothing to cover -> explains the “always 100%”.
• Reproduce the CM build locally
  • Run from the same branch/commit as CM:

    mvn --batch-mode org.jacoco:jacoco-maven-plugin:prepare-agent package
    

  • Open target/site/jacoco/index.html.
  • If this also shows 100%: your usual local command is different; the CM-style command is excluding your code.
  • If this shows realistic <100%: you likely have a CM-specific Maven profile (e.g. activated via env.CM_BUILD) changing JaCoCo config.
  • Reference for how Cloud Manager builds:  https://experienceleague.adobe.com/en/docs/experience-manager-cloud-service/content/implementing/using-cloud-manager/create-application-project/build-environment-details
    https://experienceleague.adobe.com/en/docs/experience-manager-cloud-manager/content/using/code-quality-testing
• Review (or temporarily simplify) jacoco-maven-plugin config
  • Remove aggressive includes/excludes and CM‑only overrides.
  • Start with a minimal config (let CM’s prepare-agent do the work) and confirm coverage becomes realistic; then add back only necessary exclusions (e.g. generated/precompiled code).

Thanks for the detailed explanation! I followed all steps: downloaded Code Quality CSV (only shows issues, no coverage metrics like lines_to_cover/uncovered_lines), reproduced CM build locally (mvn clean verify org.jacoco:jacoco-maven-plugin:prepare-agent package), and confirmed realistic coverage <100% in core/target/site/jacoco/index.html (~81% LINE as per jacoco.xml).​

My Setup (Standard AEM Archetype)

• Parent POM: No custom profiles (no cmBuild or env.CM_BUILD=true activation). Standard JaCoCo ${jacoco.version}=0.8.11 prop. Modules: all, core, ui.frontend, ui.apps, etc.

• Core POM (only Java module): JaCoCo plugin with:

  text

  <excludes> <exclude>**/package-info.java</exclude> <exclude>**/config/**</exclude> <!-- No business logic here --> <exclude>**/constants/**</exclude> <!-- No testable code --> <exclude>**/enums/**</exclude> <!-- Trivial --> </excludes>

  Executions: prepare-agent, report (phase=test), check (LINE>50%, BRANCH>30%). 373 tests pass locally.

  ​

Local CM command generates jacoco.exec → jacoco.xml → HTML report with 81% LINE coverage on actual classes (*.core.models.*, servlets, etc.). But pipeline stubbornly shows 100%.

What We've Ruled Out

• No Java-less modules: Sonar analyzes CM-Sonar-Build/core/src/main/java/... (CSV has issues there).

• No CM-specific profiles: Parent has only autoInstall* profiles (dev/deploy).

• JaCoCo works: Local matches expected; excludes don't zero-out lines (XML shows missed lines).

• CSV: build_project_issues.csv = issues only, no coverage data → where's the real metrics CSV?

Why Still 100%?

SonarQube's Zero Coverage Sensor assigns 100% to "simple" classes (getters/setters) + formula (CT+CF+LC)/(2B+EL) inflates it? But local XML contradicts (81% real). Or CM skips report import despite logs saying "Importing 1 reports"?

Can Adobe confirm:

1. Exact lines_to_cover/uncovered_lines for "core" module in pipeline?

2. Does CM override excludes or skip JaCoCo for certain paths?

3. Full coverage CSV (not just issues)?

Local XML proves tests aren't 100% - pipeline metric is misleading. Quality Gate passes anyway (>80% threshold), but need accurate reporting. Thoughts?

Hi ​@g.davico, 

The most likely root cause is that Cloud Manager is reporting 100% coverage because JaCoCo has no classes to measure, or is scanning only test files or already-excluded code. Here are the main reasons:

• The JaCoCo agent (prepare-agent) is not running before the test phase, so no .exec file is generated with instrumentation data
• The jacoco-maven-plugin is misconfigured and scans the wrong module (e.g., a module with no source classes, only test classes)
• The target/classes directory is empty or excluded at scan time

Other Common Root Causes:

• If your pom.xml has a <sonar.coverage.exclusions> or JaCoCo <excludes> pattern that inadvertently matches all production classes, the coverage shows as 100% (source)
• If jacoco:prepare-agent doesn't run before Surefire executes tests, no instrumentation is injected, and JaCoCo has nothing to report — defaulting to 100%

<plugin>
  <groupId>org.jacoco</groupId>
  <artifactId>jacoco-maven-plugin</artifactId>
  <version>0.8.12</version>
  <executions>
    <execution>
      <goals>
        <goal>prepare-agent</goal> <!-- Must run BEFORE tests -->
      </goals>
    </execution>
    <execution>
      <id>report</id>
      <phase>test</phase>
      <goals>
        <goal>report</goal>
      </goals>
    </execution>
  </executions>
</plugin>