test: define the-nexus genome acceptance for #672

tests/test_the_nexus_genome.py

@@ -0,0 +1,56 @@
+from pathlib import Path
+
+
+GENOME = Path("GENOME.md")
+
+
+def read_genome() -> str:
+    assert GENOME.exists(), "GENOME.md must exist at repo root"
+    return GENOME.read_text(encoding="utf-8")
+
+
+def test_the_nexus_genome_has_required_sections() -> None:
+    text = read_genome()
+    required = [
+        "# GENOME.md — the-nexus",
+        "## Project Overview",
+        "## Architecture Diagram",
+        "```mermaid",
+        "## Entry Points and Data Flow",
+        "## Key Abstractions",
+        "## API Surface",
+        "## Test Coverage Gaps",
+        "## Security Considerations",
+        "## Runtime Truth and Docs Drift",
+    ]
+    missing = [item for item in required if item not in text]
+    assert not missing, missing
+
+
+def test_the_nexus_genome_captures_current_runtime_contract() -> None:
+    text = read_genome()
+    required = [
+        "server.py",
+        "app.js",
+        "index.html",
+        "portals.json",
+        "vision.json",
+        "BROWSER_CONTRACT.md",
+        "tests/test_browser_smoke.py",
+        "tests/test_repo_truth.py",
+        "nexus/morrowind_harness.py",
+        "nexus/bannerlord_harness.py",
+        "mempalace/tunnel_sync.py",
+        "mcp_servers/desktop_control_server.py",
+        "public/nexus/",
+    ]
+    missing = [item for item in required if item not in text]
+    assert not missing, missing
+
+
+def test_the_nexus_genome_explains_docs_runtime_drift() -> None:
+    text = read_genome()
+    assert "README.md says current `main` does not ship a browser 3D world" in text
+    assert "CLAUDE.md declares root `app.js` and `index.html` as canonical frontend paths" in text
+    assert "tests and browser contract now assume the root frontend exists" in text
+    assert len(text) >= 5000