from functools import reduce
 
 from hypothesis import given
 import hypothesis.strategies as st
 import numpy as np
 import pytest
 
 import qsim.gate
 import qsim.state
 from qsim.measurement import measure
 
 from .common import (
     classical_bitstrings,
     n_qubits,
     rng,
     valid_states,
 )
 
 classical_states = classical_bitstrings.map(qsim.state.from_classical)
 arbitrary_qubit = n_qubits.flatmap(lambda n: st.integers(0, n - 1))
 
 
 @given(rng, arbitrary_qubit, classical_bitstrings)
 def test_classical_measurement(rng, qubit, bitstring):
     """Test measurements on "classical" states.
 
     The outcome of a measurement on qubit 'n' of a classical state (i.e. a state
     constructed from a classical bitstring) is the value of the n-th bit of
     the bitstring.
     """
     classical_state = qsim.state.from_classical(bitstring)
     # [::-1] because qubits are indexed from the least-significant,
     # but bitstring are written most-significant bit first.
     expected_outcome = bool(int(bitstring[::-1][qubit]))
     outcome, _ = measure(rng, qubit, classical_state)
     assert outcome == expected_outcome
 
 
 @given(rng, arbitrary_qubit, valid_states)
 def test_subsequent_measurement(rng, qubit, ket):
     """Test that subsequent measurements of the same qubit yield the same outcome."""
     outcome, measured_ket = measure(rng, qubit, ket)
     outcome2, measured_ket2 = measure(rng, qubit, measured_ket)
     assert np.allclose(measured_ket, measured_ket2)
     assert outcome == outcome2