feat: content-address complete PWA shell (Closes #511)

tests/test_frontend_bundle.py

@@ -42,6 +42,64 @@ def test_page_runtime_is_one_deterministic_content_addressed_bundle(tmp_path):
     assert changed.runtime_bytes != first.runtime_bytes
 
 
+def test_css_only_release_gets_a_new_shell_generation(tmp_path):
+    first = build_frontend(FRONTEND)
+    changed_frontend = tmp_path / "frontend"
+    shutil.copytree(FRONTEND, changed_frontend)
+    (changed_frontend / "dashboard.css").write_text(
+        (changed_frontend / "dashboard.css").read_text() + "\n/* release change */\n"
+    )
+
+    changed = build_frontend(changed_frontend)
+
+    assert changed.runtime_name == first.runtime_name
+    assert changed.runtime_bytes == first.runtime_bytes
+    assert changed.shell_digest != first.shell_digest
+    assert f"const CACHE = 'stackchain-dashboard-shell-{changed.shell_digest}';" in (
+        changed.service_worker_source
+    )
+
+
+@pytest.mark.parametrize(
+    "asset",
+    [
+        "manifest.webmanifest",
+        "icons/stackchain-192.png",
+        "icons/stackchain-512.png",
+        "background-issue-sync.js",
+        "service-worker.js",
+    ],
+)
+def test_every_offline_shell_asset_versions_the_shell_generation(tmp_path, asset):
+    first = build_frontend(FRONTEND)
+    changed_frontend = tmp_path / "frontend"
+    shutil.copytree(FRONTEND, changed_frontend)
+    path = changed_frontend / asset
+    path.write_bytes(path.read_bytes() + b"\nrelease-change")
+
+    changed = build_frontend(changed_frontend)
+
+    assert changed.shell_digest != first.shell_digest
+
+
+def test_legacy_cache_marker_is_normalized_out_of_build_identity(tmp_path):
+    first = build_frontend(FRONTEND)
+    changed_frontend = tmp_path / "frontend"
+    shutil.copytree(FRONTEND, changed_frontend)
+    worker = changed_frontend / "service-worker.js"
+    worker.write_text(
+        worker.read_text().replace(
+            "const CACHE = 'stackchain-dashboard-shell-v85';",
+            "const CACHE = 'stackchain-dashboard-shell-v999';",
+        )
+    )
+
+    changed = build_frontend(changed_frontend)
+
+    assert changed.shell_digest == first.shell_digest
+    assert changed.service_worker_source == first.service_worker_source
+
+
 @pytest.mark.anyio
 async def test_runtime_is_transferred_as_gzip_when_the_client_accepts_it():
     transport = httpx.ASGITransport(app=main.app)