tests/test_models.py

"""Tests for QSVAPS data models."""

import pytest
from qsvaps.models import (
    Plan,
    PlanAction,
    PlanConstraint,
    ResourceConstraint,
    ConstraintType,
    FailureWitness,
    VerificationResult,
    VariableMapping,
)


class TestPlanAction:
    def test_basic_creation(self):
        action = PlanAction(name="fetch", description="Fetch data")
        assert action.name == "fetch"
        assert action.description == "Fetch data"
        assert action.can_fail is True
        assert action.fallback is None
        assert action.resources == []

    def test_with_resources(self):
        action = PlanAction(
            name="process",
            resources=["gpu", "memory"],
            can_fail=False,
        )
        assert action.resources == ["gpu", "memory"]
        assert action.can_fail is False

    def test_with_fallback(self):
        action = PlanAction(name="main", fallback="backup")
        assert action.fallback == "backup"


class TestPlan:
    def test_basic_plan(self):
        plan = Plan(
            name="Test Plan",
            actions=[
                PlanAction(name="a"),
                PlanAction(name="b"),
            ],
            dependencies=[("a", "b")],
        )
        assert len(plan.actions) == 2
        assert plan.action_names == ["a", "b"]

    def test_get_action(self):
        plan = Plan(
            name="Test",
            actions=[PlanAction(name="x"), PlanAction(name="y")],
        )
        assert plan.get_action("x").name == "x"
        assert plan.get_action("z") is None

    def test_get_action_index(self):
        plan = Plan(
            name="Test",
            actions=[PlanAction(name="a"), PlanAction(name="b")],
        )
        assert plan.get_action_index("a") == 0
        assert plan.get_action_index("b") == 1
        assert plan.get_action_index("c") == -1


class TestVariableMapping:
    def test_num_variables(self):
        vm = VariableMapping(
            variables={"s_a": 0, "s_b": 1},
            descriptions={"s_a": "A succeeds", "s_b": "B succeeds"},
        )
        assert vm.num_variables == 2

    def test_get_var_name(self):
        vm = VariableMapping(variables={"s_a": 0, "s_b": 1})
        assert vm.get_var_name(0) == "s_a"
        assert vm.get_var_name(1) == "s_b"
        assert vm.get_var_name(99) == "x99"

    def test_get_description(self):
        vm = VariableMapping(
            variables={"s_a": 0},
            descriptions={"s_a": "Action A succeeds"},
        )
        assert vm.get_description(0) == "Action A succeeds"


class TestFailureWitness:
    def test_creation(self):
        constraint = PlanConstraint(
            expression="x0",
            description="A must succeed",
            constraint_type=ConstraintType.COMPLETION,
        )
        witness = FailureWitness(
            assignment={"s_a": False},
            violated_constraints=[constraint],
            bitstring="0",
            measurement_count=42,
            explanation="A failed",
        )
        assert witness.measurement_count == 42
        assert len(witness.violated_constraints) == 1


class TestVerificationResult:
    def test_safe_result(self):
        plan = Plan(name="Safe", actions=[])
        result = VerificationResult(
            plan=plan,
            is_safe=True,
            witnesses=[],
            num_variables=3,
            num_violations=0,
            total_states=8,
            grover_iterations=0,
        )
        assert result.is_safe
        assert result.num_violations == 0