Show merged code coverage alongside homepage test results

.github/scripts/render-homepage-tests.py

@@ -9,7 +9,29 @@
             "MariaDB", "Firebird", "Db2", "Informix", "Sybase", "Hana"}
 
 
-def render(results, run):
+def render_coverage(report, run):
+    if report is None or not pathlib.Path(report).is_file():
+        return '<p>Code coverage unavailable for this run: no merged coverage artifact is available.</p>'
+    root = ET.parse(report).getroot()
+    if root.tag != 'coverage':
+        raise ValueError('Expected a Cobertura coverage report')
+    items = []
+    for metric, label in (("lines", "line coverage"), ("branches", "branch coverage")):
+        covered = int(root.attrib[f'{metric}-covered'])
+        total = int(root.attrib[f'{metric}-valid'])
+        if not 0 <= covered <= total or (metric == 'lines' and total == 0):
+            raise ValueError(f'Invalid {metric} coverage')
+        rate = f'{100 * covered / total:.2f}%' if total else 'N/A'
+        items.append(f'<li><strong>{rate}</strong>{label}<small>{covered:,} / {total:,} covered</small></li>')
+    url = html.escape(run.get('coverage_url', run['html_url']), quote=True)
+    return ('<h3>Code coverage</h3><ul class="test-counts coverage-counts">' + ''.join(items)
+            + '</ul><p>Production assemblies, merged across unit and database suites; '
+            'shared code is counted once. '
+            f'<a href="{url}">Download the full HTML coverage report ↗</a> '
+            '(code-coverage artifact; open index.html).</p>')
+
+
+def render(results, run, coverage=None):
     suites = {}
     for path in pathlib.Path(results).rglob("*.trx"):
         name = path.stem
@@ -27,22 +49,24 @@ def render(results, run):
     sha = html.escape(run["head_sha"][:7])
     date = html.escape(run["updated_at"])
     conclusion = html.escape(run["conclusion"] or "unknown")
-    source = f'<p><a href="{url}">CI run · {sha}</a> · {date} · workflow: {conclusion}. Latest completed master run at deployment time.</p>'
+    source = f'<p><a href="{url}">CI run · {sha}</a> · {date} · workflow: {conclusion}. Latest completed master run at deployment time.</p>'
+    coverage_html = render_coverage(coverage, run)
     if set(suites) != EXPECTED:
-        return source + f'<p>Incomplete test results: {len(suites)} of {len(EXPECTED)} suites available. Full totals unavailable; inspect the run for failures or missing artifacts.</p>'
+        return source + f'<p>Incomplete test results: {len(suites)} of {len(EXPECTED)} suites available. Full totals unavailable; inspect the run for failures or missing artifacts.</p>' + coverage_html
     totals = {key: sum(s[key] for s in suites.values()) for key in ("total", "executed", "passed", "failed")}
     totals["skipped"] = totals["total"] - totals["executed"]
     totals["other"] = totals["executed"] - totals["passed"] - totals["failed"]
     counts = '<ul class="test-counts">' + ''.join(f'<li><strong>{totals[key]:,}</strong>{label}</li>' for key, label in (("executed", "executed"), ("passed", "passed"), ("failed", "failed"), ("skipped", "skipped / not executed"), ("other", "other outcomes"))) + '</ul>'
-    return counts + source
+    return counts + coverage_html + source
 
 
 if __name__ == "__main__":
-    results, metadata, page = sys.argv[1:]
+    results, metadata, page = sys.argv[1:4]
+    coverage = sys.argv[4] if len(sys.argv) > 4 else None
     target = pathlib.Path(page)
     content = target.read_text(encoding="utf-8")
     start = "<!-- TEST_RESULTS_START -->"
     end = "<!-- TEST_RESULTS_END -->"
     before, remainder = content.split(start, 1)
     _, after = remainder.split(end, 1)
-    target.write_text(before + start + "\n" + render(results, json.loads(pathlib.Path(metadata).read_text(encoding="utf-8"))) + "\n" + end + after, encoding="utf-8")
+    target.write_text(before + start + "\n" + render(results, json.loads(pathlib.Path(metadata).read_text(encoding="utf-8")), coverage) + "\n" + end + after, encoding="utf-8")

.github/scripts/test-homepage-tests.py

@@ -51,10 +51,53 @@ def test_duplicate_suite_rejected(self):
         with self.assertRaises(ValueError):
             renderer.render(self.root, self.run)
 
-    def test_invalid_counts_rejected(self):
+    def test_invalid_counts_rejected(self):
         self.populate(passed=8)
         with self.assertRaises(ValueError):
-            renderer.render(self.root, self.run)
+            renderer.render(self.root, self.run)
+
+    def coverage(self, lines=75, total=100, branches=2, branch_total=3):
+        path = self.root / 'Cobertura.xml'
+        path.write_text(f'<coverage lines-covered="{lines}" lines-valid="{total}" '
+                        f'branches-covered="{branches}" branches-valid="{branch_total}"/>')
+        return path
+
+    def test_merged_coverage_and_report_link(self):
+        self.populate()
+        self.run['coverage_url'] = self.run['html_url'] + '/artifacts/123'
+        result = renderer.render(self.root, self.run, self.coverage())
+        for text in ('75.00%</strong>line coverage', '66.67%</strong>branch coverage',
+                     '75 / 100 covered', '2 / 3 covered', '/artifacts/123', '48</strong>executed'):
+            self.assertIn(text, result)
+
+    def test_missing_coverage_preserves_test_results(self):
+        self.populate()
+        result = renderer.render(self.root, self.run, self.root / 'missing.xml')
+        self.assertIn('Code coverage unavailable for this run', result)
+        self.assertIn('48</strong>executed', result)
+        self.assertNotIn('0.00%', result)
+
+    def test_zero_branches_is_not_zero_percent(self):
+        result = renderer.render(self.root, self.run, self.coverage(branches=0, branch_total=0))
+        self.assertIn('N/A</strong>branch coverage', result)
+
+    def test_invalid_coverage_rejected(self):
+        for values in ({'lines': 101}, {'lines': -1}, {'total': 0}, {'branches': 4}):
+            with self.subTest(values=values), self.assertRaises(ValueError):
+                renderer.render(self.root, self.run, self.coverage(**values))
+
+    def test_incomplete_tests_still_identify_coverage_source(self):
+        result = renderer.render(self.root, self.run, self.coverage())
+        self.assertIn('Incomplete test results: 0 of 12', result)
+        self.assertIn('75.00%', result)
+        self.assertIn('abc1234', result)
+
+    def test_suite_coverage_is_not_used_as_merged_coverage(self):
+        self.populate()
+        self.coverage()
+        result = renderer.render(self.root, self.run)
+        self.assertIn('Code coverage unavailable', result)
+        self.assertNotIn('75.00%', result)
 
 
 if __name__ == '__main__':

.github/workflows/pages.yml

@@ -44,7 +44,7 @@ jobs:
         run: |
           python3 -B .github/scripts/build-docs.py --check
           python3 -B .github/scripts/verify-docs.py
-      - name: Verify test-count renderer
+      - name: Verify test-count and coverage renderer
         run: python3 .github/scripts/test-homepage-tests.py
       - name: Select latest completed master test run
         id: tests
@@ -58,6 +58,14 @@ jobs:
             });
             const run = data.workflow_runs[0];
             if (run) {
+              const artifacts = await github.paginate(github.rest.actions.listWorkflowRunArtifacts, {
+                ...context.repo, run_id: run.id, per_page: 100
+              });
+              const coverage = artifacts.find(a => a.name === 'code-coverage' && !a.expired);
+              if (coverage) {
+                run.coverage_url = `${run.html_url}/artifacts/${coverage.id}`;
+                core.setOutput('has-coverage', 'true');
+              }
               fs.writeFileSync('ci-run.json', JSON.stringify(run));
               core.setOutput('run-id', String(run.id));
             }
@@ -69,9 +77,17 @@ jobs:
           run-id: ${{ steps.tests.outputs.run-id }}
           pattern: test-results-*
           path: ci-results
-      - name: Render test counts and provenance
+      - name: Download merged coverage from the same run
+        if: steps.tests.outputs.has-coverage == 'true'
+        uses: actions/download-artifact@v4
+        with:
+          github-token: ${{ github.token }}
+          run-id: ${{ steps.tests.outputs.run-id }}
+          name: code-coverage
+          path: ci-coverage
+      - name: Render test counts, coverage and provenance
         if: steps.tests.outputs.run-id != ''
-        run: python3 .github/scripts/render-homepage-tests.py ci-results ci-run.json docs/index.html
+        run: python3 .github/scripts/render-homepage-tests.py ci-results ci-run.json docs/index.html ci-coverage/Cobertura.xml
       - uses: actions/configure-pages@v5
       - uses: actions/upload-pages-artifact@v4
         with:

README.md

@@ -9,7 +9,7 @@
 [![Source target: .NET 9](https://img.shields.io/badge/source_target-.NET_9-512BD4)](src/Migrator/DotNetProjects.Migrator.csproj)
 [![License: MPL-1.1](https://img.shields.io/badge/license-MPL--1.1-blue.svg)](https://www.mozilla.org/en-US/MPL/1.1/)
 
-[Homepage](https://dotnetprojects.github.io/Migrator.NET/) · [Documentation](https://dotnetprojects.github.io/Migrator.NET/guide/) · [NuGet](https://www.nuget.org/packages/DotNetProjects.Migrator/) · [Releases](https://github.com/dotnetprojects/Migrator.NET/releases) · [Issues](https://github.com/dotnetprojects/Migrator.NET/issues) · [Feature comparison](https://dotnetprojects.github.io/Migrator.NET/#compare) · [CI test counts](https://dotnetprojects.github.io/Migrator.NET/#test-results)
+[Homepage](https://dotnetprojects.github.io/Migrator.NET/) · [Documentation](https://dotnetprojects.github.io/Migrator.NET/guide/) · [NuGet](https://www.nuget.org/packages/DotNetProjects.Migrator/) · [Releases](https://github.com/dotnetprojects/Migrator.NET/releases) · [Issues](https://github.com/dotnetprojects/Migrator.NET/issues) · [Feature comparison](https://dotnetprojects.github.io/Migrator.NET/#compare) · [CI test results & coverage](https://dotnetprojects.github.io/Migrator.NET/#test-results)
 
 DotNetProjects.Migrator is a fork of [Migrator.NET](https://github.com/migratordotnet/Migrator.NET). Write each schema change as a numbered C# class, commit it alongside your application, and use the runner to bring a database to the required version. The database records which migrations have already been applied.
 

docs/README.md

@@ -45,13 +45,18 @@ The comparison distinguishes source capabilities from guarantees about released
 
 The quick start targets .NET 9 and installs the core library and SQLite driver through NuGet. Sample validation uses local project references to catch API drift. The SQLite driver version matches the repository test dependency.
 
-## Status badges and test counts
+## Status badges, test counts and code coverage
 
 The homepage links to master CI results and NuGet, and identifies the MPL-1.1 license.
 Pages also redeploys when master CI completes. During deployment it selects the latest
 completed master push run (including failures), downloads its TRX artifacts, and renders
 executed/passed/failed/skipped/other counts with the run URL, commit and timestamp.
-Counts are a deployment snapshot, not code coverage or a guarantee about every provider.
+The same run supplies the merged `code-coverage` artifact. Pages displays line and branch
+coverage percentages and covered/total counts for production assemblies, with a link to
+the downloadable HTML report (open `index.html`). Shared code is counted once in the
+merged report; suite percentages are never added or averaged. A missing or expired
+coverage artifact is shown as unavailable, never as 0% or replaced by another run.
+Counts and coverage are a deployment snapshot, not a guarantee about every provider.
 Missing suites produce an incomplete-results message, never a partial success total.
 The committed/local page shows a fallback link until deployment supplies results.
 The renderer only changes the uploaded Pages artifact; it does not commit generated counts. Preserve `TEST_RESULTS_START` and `TEST_RESULTS_END` in `_src/home.html`.

docs/_src/home.html

@@ -25,8 +25,8 @@ <h1 id="hero-title">Database changes,<br><em>written in C#.</em></h1>
   <section class="container section start-grid" id="quick-start" aria-labelledby="start-title"><div><p class="eyebrow">FROM EMPTY FOLDER TO FIRST TABLE</p><h2 id="start-title">Start with<br><em>one change.</em></h2><p>Install the library and your database driver. Add the migration above, wire up the runner, and apply it. SQLite makes a convenient first database.</p><a class="button primary" href="guide/quick-start.html">Follow the complete quick start ↗</a></div>{{install}}</section>
   <section class="manual-preview container section" aria-labelledby="manual-title"><div class="section-heading"><div><p class="eyebrow">THE MIGRATION MANUAL</p><h2 id="manual-title">Past “hello, table.”</h2></div><p>Detailed guides, paired examples, and provider notes.<br><a href="guide/index.html">Browse every chapter ↗</a></p></div><div class="chapter-preview"><a href="guide/creating-tables.html"><span>01 / AUTHORING</span><h3>Shape the schema ↗</h3><p>Tables, columns, data, indexes and constraints.</p></a><a href="guide/configuration.html"><span>02 / EXECUTION</span><h3>Control the run ↗</h3><p>Configuration, transactions, DI, CLI and SQL preview.</p></a><a href="guide/providers.html"><span>03 / DATABASES</span><h3>Know your provider ↗</h3><p>Storage behavior, SQLite rebuilds and engine differences.</p></a><a href="guide/testing.html"><span>04 / PRACTICE</span><h3>Ship with evidence ↗</h3><p>Reversals, conditional changes, testing and upgrades.</p></a></div></section>
   <section class="provider-section container section" id="providers" aria-labelledby="provider-title"><p class="eyebrow">BRING YOUR DATABASE</p><h2 id="provider-title">One migration system.<br><em>Many dialects.</em></h2><ul class="provider-list"><li><a href="guide/sqlite.html">SQLite</a></li><li><a href="guide/sql-server.html">SQL Server</a></li><li><a href="guide/postgresql.html">PostgreSQL</a></li><li><a href="guide/mysql.html">MySQL</a></li><li><a href="guide/mysql.html">MariaDB</a></li><li><a href="guide/oracle.html">Oracle</a></li><li><a href="guide/other-providers.html">Firebird</a></li><li><a href="guide/other-providers.html">Db2</a></li><li><a href="guide/other-providers.html">Informix</a></li><li><a href="guide/other-providers.html">Sybase</a></li><li><a href="guide/other-providers.html">SAP HANA</a></li><li><a href="guide/other-providers.html">Ingres</a></li></ul><p>Capabilities follow the database engine. The <a href="guide/providers.html">provider guide</a> explains aliases, drivers and operation-specific behavior.</p></section>
-  <section class="container section ci-section" id="test-results" aria-labelledby="tests-title"><p class="eyebrow">BUILD AND DATABASE TESTS</p><h2 id="tests-title">Evidence from CI.</h2><p>The CI matrix runs unit tests and 11 database suites, then checks for missing or duplicate test assignments. Counts represent test executions across the matrix; skipped tests are shown separately.</p><!-- TEST_RESULTS_START -->
-<p>Test totals are populated during deployment from the latest completed master CI run. <a href="https://github.com/dotnetprojects/Migrator.NET/actions/workflows/dotnetpull.yml?query=branch%3Amaster">View CI runs and test-result artifacts ↗</a>.</p>
+  <section class="container section ci-section" id="test-results" aria-labelledby="tests-title"><p class="eyebrow">TEST RESULTS AND CODE COVERAGE</p><h2 id="tests-title">Evidence from CI.</h2><p>The CI matrix runs unit tests and 11 database suites, then checks for missing or duplicate test assignments. Counts represent test executions across the matrix; skipped tests are shown separately. Line and branch coverage measure production code across the combined suites.</p><!-- TEST_RESULTS_START -->
+<p>Test totals and code coverage are populated during deployment from the latest completed master CI run. <a href="https://github.com/dotnetprojects/Migrator.NET/actions/workflows/dotnetpull.yml?query=branch%3Amaster">View CI runs and test-result artifacts ↗</a>.</p>
 <!-- TEST_RESULTS_END --></section>
   {{comparison}}
   <section class="closing-section container"><p class="eyebrow">EXPLICIT CHANGES. A LASTING RECORD.</p><h2>The next version<br><em>starts with a change.</em></h2><a class="button primary" href="guide/quick-start.html">Open the manual ↗</a><a class="text-link" href="https://github.com/dotnetprojects/Migrator.NET">Contribute on GitHub →</a></section>

docs/assets/site.css

@@ -553,7 +553,13 @@ img {
   font-size:14px;
   color:var(--muted);
 }
-.test-counts {
+.coverage-counts small {
+  display: block;
+  margin-top: 6px;
+  color: var(--muted);
+  font-size: 12px;
+}
+.test-counts {
   display:flex;
   list-style:none;
   gap:35px;