Add integration and unit tests for scanner routing, TTM analysis, vendor fail-fast, and yfinance data layer

- Implement integration tests for scanner vendor routing, ensuring correct routing to Alpha Vantage and fallback to yfinance.
- Create comprehensive unit tests for TTM analysis, covering metrics computation and report formatting.
- Introduce fail-fast vendor routing tests to verify immediate failure for methods not in FALLBACK_ALLOWED.
- Develop extensive integration tests for the yfinance data layer, mocking external calls to validate functionality across various financial data retrieval methods.

pyproject.toml

@@ -43,10 +43,18 @@ include = ["tradingagents*", "cli*"]
 [dependency-groups]
 dev = [
     "pytest>=9.0.2",
+    "pytest-recording>=0.13.2",
+    "vcrpy>=6.0.2",
+    "pytest-socket>=0.7.0",
 ]
 
 [tool.pytest.ini_options]
+testpaths = ["tests"]
 markers = [
-    "integration: marks tests as live integration tests requiring real API keys",
+    "integration: tests that replay VCR cassettes of data API calls",
+    "e2e: tests that hit real LLM APIs (manual trigger only)",
+    "vcr: tests that use VCR cassette recording",
+    "slow: tests that take a long time to run",
     "paid_tier: marks tests that require a paid Finnhub subscription (free tier returns HTTP 403)",
 ]
+addopts = "--ignore=tests/integration --ignore=tests/e2e --disable-socket --allow-unix-socket -x -q"

tests/e2e/conftest.py

@@ -0,0 +1,10 @@
+"""E2E test configuration — real LLM API calls, manual trigger only."""
+
+import pytest
+
+
+def pytest_collection_modifyitems(config, items):
+    """Mark all e2e tests as slow."""
+    for item in items:
+        item.add_marker(pytest.mark.e2e)
+        item.add_marker(pytest.mark.slow)

tests/integration/conftest.py

@@ -0,0 +1,29 @@
+"""Integration test configuration — VCR cassette replay for data API tests."""
+
+import os
+import pytest
+
+
+@pytest.fixture(scope="module")
+def vcr_config():
+    return {
+        "cassette_library_dir": "tests/cassettes",
+        "record_mode": "none",
+        "match_on": ["method", "scheme", "host", "port", "path"],
+        "filter_headers": [
+            "Authorization",
+            "Cookie",
+            "X-Api-Key",
+        ],
+        "filter_query_parameters": [
+            "apikey",
+            "token",
+        ],
+        "decode_compressed_response": True,
+    }
+
+
+@pytest.fixture
+def av_api_key():
+    """Return the Alpha Vantage API key for integration tests."""
+    return os.environ.get("ALPHA_VANTAGE_API_KEY", "demo")

tests/unit/conftest.py

@@ -0,0 +1,73 @@
+"""Shared mock factories for unit tests.
+
+Network is blocked by pytest-socket (--disable-socket in addopts).
+No test in tests/unit/ can hit a real API.
+"""
+
+import json
+import pandas as pd
+import pytest
+from unittest.mock import MagicMock
+
+
+# -- yfinance mock factories --
+
+
+@pytest.fixture
+def mock_yf_screener():
+    """Pre-built yfinance screener mock."""
+
+    def _make(quotes):
+        return {"quotes": quotes}
+
+    return _make
+
+
+@pytest.fixture
+def mock_yf_download():
+    """Pre-built yfinance download mock returning a MultiIndex DataFrame."""
+
+    def _make(symbols, periods=5, base_price=100.0):
+        idx = pd.date_range("2024-01-04", periods=periods, freq="B")
+        data = {s: [base_price + i for i in range(periods)] for s in symbols}
+        df = pd.DataFrame(data, index=idx)
+        df.columns = pd.MultiIndex.from_product([["Close"], symbols])
+        return df
+
+    return _make
+
+
+# -- Alpha Vantage mock factories --
+
+
+@pytest.fixture
+def mock_av_request():
+    """Pre-built Alpha Vantage _rate_limited_request mock."""
+
+    def _make(responses: dict):
+        """responses: {function_name: return_value} or callable."""
+
+        def fake(function_name, params=None, **kwargs):
+            if callable(responses.get(function_name)):
+                return responses[function_name](params)
+            return json.dumps(responses.get(function_name, {}))
+
+        return fake
+
+    return _make
+
+
+# -- LLM mock factories --
+
+
+@pytest.fixture
+def mock_llm():
+    """Pre-built LLM mock that returns canned responses."""
+
+    def _make(content="Mocked LLM response."):
+        llm = MagicMock()
+        llm.invoke.return_value = MagicMock(content=content)
+        llm.ainvoke.return_value = MagicMock(content=content)
+        return llm
+
+    return _make