feat: Add comprehensive test suite for project and scenario models

tests/test_project_scenario_models.py

@@ -0,0 +1,142 @@
+from __future__ import annotations
+
+from collections.abc import Iterator
+from datetime import datetime, timedelta, timezone
+
+import pytest
+from sqlalchemy import create_engine, select
+from sqlalchemy.exc import IntegrityError
+from sqlalchemy.orm import Session, sessionmaker
+
+from config.database import Base
+from models import (
+    MiningOperationType,
+    Project,
+    ProjectProfitability,
+    Scenario,
+    ScenarioProfitability,
+    ScenarioStatus,
+)
+
+
+@pytest.fixture()
+def engine() -> Iterator:
+    engine = create_engine("sqlite:///:memory:", future=True)
+    Base.metadata.create_all(bind=engine)
+    try:
+        yield engine
+    finally:
+        Base.metadata.drop_all(bind=engine)
+
+
+@pytest.fixture()
+def session(engine) -> Iterator[Session]:
+    TestingSession = sessionmaker(
+        bind=engine, expire_on_commit=False, future=True)
+    session = TestingSession()
+    try:
+        yield session
+    finally:
+        session.close()
+
+
+def test_project_scenario_cascade_deletes(session: Session) -> None:
+    project = Project(name="Cascade Mine",
+                      operation_type=MiningOperationType.OTHER)
+    scenario_a = Scenario(
+        name="Base Case", status=ScenarioStatus.DRAFT, project=project)
+    scenario_b = Scenario(
+        name="Expansion", status=ScenarioStatus.DRAFT, project=project)
+
+    session.add(project)
+    session.commit()
+
+    assert session.scalar(select(Project).where(
+        Project.id == project.id)) is not None
+    assert len(session.scalars(select(Scenario).where(
+        Scenario.project_id == project.id)).all()) == 2
+
+    session.delete(project)
+    session.commit()
+
+    assert session.scalar(select(Project).where(
+        Project.id == project.id)) is None
+    assert session.scalars(select(Scenario)).first() is None
+
+
+def test_scenario_unique_name_per_project(session: Session) -> None:
+    project = Project(name="Uniqueness Mine",
+                      operation_type=MiningOperationType.OTHER)
+    scenario = Scenario(name="Duplicated",
+                        status=ScenarioStatus.DRAFT, project=project)
+    session.add_all([project, scenario])
+    session.commit()
+
+    duplicate = Scenario(
+        name="Duplicated", status=ScenarioStatus.DRAFT, project=project)
+    session.add(duplicate)
+
+    with pytest.raises(IntegrityError):
+        session.commit()
+    session.rollback()
+
+
+def test_latest_profitability_helpers(session: Session) -> None:
+    project = Project(name="Hierarchy Mine",
+                      operation_type=MiningOperationType.OTHER)
+    scenario = Scenario(name="Economic Model",
+                        status=ScenarioStatus.DRAFT, project=project)
+    session.add_all([project, scenario])
+    session.commit()
+
+    base_time = datetime.now(timezone.utc)
+    scenario_snapshot_old = ScenarioProfitability(
+        scenario=scenario,
+        npv=1_000_000,
+        calculated_at=base_time,
+    )
+    scenario_snapshot_new = ScenarioProfitability(
+        scenario=scenario,
+        npv=2_500_000,
+        calculated_at=base_time + timedelta(hours=6),
+    )
+    project_snapshot_old = ProjectProfitability(
+        project=project,
+        npv=5_000_000,
+        calculated_at=base_time,
+    )
+    project_snapshot_new = ProjectProfitability(
+        project=project,
+        npv=7_500_000,
+        calculated_at=base_time + timedelta(hours=12),
+    )
+
+    session.add_all(
+        [
+            scenario_snapshot_old,
+            scenario_snapshot_new,
+            project_snapshot_old,
+            project_snapshot_new,
+        ]
+    )
+    session.commit()
+
+    session.refresh(scenario)
+    session.refresh(project)
+
+    assert scenario.latest_profitability is scenario_snapshot_new
+    assert project.latest_profitability is project_snapshot_new
+
+
+def test_currency_normalisation_on_model(session: Session) -> None:
+    project = Project(name="Forex Mine",
+                      operation_type=MiningOperationType.OTHER)
+    scenario = Scenario(
+        name="Currency Case", status=ScenarioStatus.DRAFT, project=project, currency="usd")
+
+    session.add_all([project, scenario])
+    session.commit()
+
+    session.refresh(scenario)
+
+    assert scenario.currency == "USD"