"""Fan-out contract tests. Author: Sandeep Belgavi."""
import threading
import time
import unittest
from pattern_05 import collect

class ParallelTests(unittest.TestCase):
    def test_disagreement(self): self.assertEqual(collect({"a": lambda: "normal", "b": lambda: "degraded"})["status"], "conflict")
    def test_agreement(self): self.assertEqual(collect({"a": lambda: "normal"})["status"], "consistent")
    def test_error_retained(self):
        def fail(): raise RuntimeError()
        self.assertEqual(collect({"a": fail})["failures"], ["a"])
    def test_invalid_output(self): self.assertEqual(collect({"a": lambda: "fixed"})["status"], "incomplete")
    def test_no_empty_success(self):
        with self.assertRaises(ValueError): collect({})
    def test_deterministic_order(self): self.assertEqual(list(collect({"z": lambda: "normal", "a": lambda: "normal"})["results"]), ["a", "z"])
    def test_worker_limit(self):
        active = peak = 0
        lock = threading.Lock()
        def work():
            nonlocal active, peak
            with lock: active += 1; peak = max(peak, active)
            time.sleep(.01)
            with lock: active -= 1
            return "normal"
        collect({str(i): work for i in range(6)}, limit=2)
        self.assertLessEqual(peak, 2)
        self.assertEqual(active, 0)
    def test_invalid_limit(self):
        with self.assertRaises(ValueError): collect({"a": lambda: "normal"}, True)

if __name__ == "__main__": unittest.main()