Battle-for-Tismo/tests/rules_test.js

import { TestCase } from "./framework/test_case.js";
import {
  buildingBuildCost,
  buildingRefund,
  buildingUpkeep,
  buildingEffectValue,
  governmentChangeCost,
  governmentEffects,
  technologyEffects,
  prerequisitesMet,
  defenseFactors,
  defenseMultiplier,
  unitDefense,
} from "../shared/rules.js";
import {
  effectValue,
  GOVERNMENTS,
  TECHNOLOGIES,
  TERRAIN_TILES,
  EFFECT_GDP,
  EFFECT_RESEARCH,
  EFFECT_CULTURE,
} from "../shared/data.js";

function proto(overrides = {}) {
  return {
    baseCost: 0,
    costAlpha: 1.5,
    refundFraction: 0.5,
    effects: [],
    ...overrides,
  };
}

export class RulesTest extends TestCase {
  test_build_cost_grows_exponentially_with_level() {
    const building = proto({ baseCost: 100, costAlpha: 2.0 });
    this.assertApprox(buildingBuildCost(building, 0), 100);
    this.assertApprox(buildingBuildCost(building, 1), 200);
    this.assertApprox(buildingBuildCost(building, 2), 400);
  }

  test_build_cost_is_fixed_and_independent_of_gdp() {
    const building = proto({ baseCost: 100, costAlpha: 1.5 });
    this.assertApprox(buildingBuildCost(building, 0), 100);
    this.assertApprox(buildingBuildCost(building, 3), 100 * Math.pow(1.5, 3));
  }

  test_upkeep_is_one_percent_of_the_levels_build_cost() {
    const building = proto({ baseCost: 100, costAlpha: 2.0 });
    this.assertEqual(buildingUpkeep(building, 0), 0);
    this.assertApprox(buildingUpkeep(building, 1), 1);
    this.assertApprox(buildingUpkeep(building, 2), 2);
    this.assertApprox(buildingUpkeep(building, 3), 4);
  }

  test_refund_is_a_fraction_of_the_removed_level() {
    const building = proto({ baseCost: 100, refundFraction: 0.5 });
    this.assertApprox(buildingRefund(building, 1), 50);
    this.assertApprox(buildingRefund(building, 2), 75);
  }

  test_effect_is_linear_or_sublinear() {
    this.assertApprox(effectValue({ baseValue: 10, exponent: 1 }, 3), 30);
    this.assertEqual(effectValue({ baseValue: 10, exponent: 1 }, 0), 0);
    this.assertApprox(effectValue({ baseValue: 10, exponent: 0.5 }, 4), 20);
    this.assertLess(
      effectValue({ baseValue: 10, exponent: 0.5 }, 4),
      effectValue({ baseValue: 10, exponent: 1 }, 4)
    );
  }

  test_building_effect_value_sums_matching_stats() {
    const building = proto({
      effects: [
        { stat: "gdp", baseValue: 0.04, exponent: 0.75 },
        { stat: "gdp", baseValue: 0.01, exponent: 1.0 },
        { stat: "culture", baseValue: 1.0, exponent: 1.0 },
      ],
    });
    this.assertApprox(buildingEffectValue(building, "gdp", 1), 0.05);
    this.assertApprox(buildingEffectValue(building, "culture", 1), 1.0);
    this.assertEqual(buildingEffectValue(building, "research", 1), 0);
    this.assertEqual(buildingEffectValue(building, "gdp", 0), 0);
  }

  test_government_change_cost() {
    const government = { baseCost: 100, costGdpFraction: 0.01 };
    this.assertApprox(governmentChangeCost(government, 1000), 110);
    this.assertApprox(governmentChangeCost(government, 10000), 200);
    this.assertApprox(governmentChangeCost(government, -50), 100);
  }

  test_catalogue_effects() {
    const monarchy = GOVERNMENTS.find((g) => g.id === "monarchy");
    this.assertApprox(governmentEffects(monarchy)[EFFECT_GDP], 0.1);
    this.assertApprox(governmentEffects(monarchy)[EFFECT_CULTURE], 1.0);
    const technocracy = GOVERNMENTS.find((g) => g.id === "technocracy");
    this.assertGreater(
      governmentEffects(technocracy)[EFFECT_RESEARCH],
      governmentEffects(monarchy)[EFFECT_RESEARCH] || 0
    );
    const method = TECHNOLOGIES.find((t) => t.id === "scientific_method");
    this.assertApprox(technologyEffects(method)[EFFECT_RESEARCH], 1.0);
    this.assertApprox(technologyEffects(method)[EFFECT_GDP], 0.02);
  }

  test_prerequisites_met() {
    const space = TECHNOLOGIES.find((t) => t.id === "space_program");
    this.assertFalse(prerequisitesMet(space, new Set(), TECHNOLOGIES));
    const index = (id) => TECHNOLOGIES.findIndex((t) => t.id === id);
    this.assertFalse(
      prerequisitesMet(space, new Set([index("scientific_method"), index("industrial_automation")]), TECHNOLOGIES)
    );
    this.assertTrue(
      prerequisitesMet(
        space,
        new Set([index("scientific_method"), index("industrial_automation"), index("quantum_computing")]),
        TECHNOLOGIES
      )
    );
  }

  test_root_technology_has_no_prerequisites() {
    const method = TECHNOLOGIES.find((t) => t.id === "scientific_method");
    this.assertEmpty(method.prerequisites);
    this.assertTrue(prerequisitesMet(method, new Set(), TECHNOLOGIES));
  }

  test_defense_factors_come_from_the_tile_and_its_city() {
    const mountain = TERRAIN_TILES.find((t) => t.terrainType === "Mountain");
    const plains = TERRAIN_TILES.find((t) => t.terrainType === "Land");
    this.assertSize(defenseFactors(plains, false), 0, "open land defends normally");
    this.assertSize(defenseFactors(null, false), 0, "no tile, no factor");

    const mountainFactors = defenseFactors(mountain, false);
    this.assertSize(mountainFactors, 1);
    this.assertEqual(mountainFactors[0].label, "Mountain");
    this.assertApprox(mountainFactors[0].bonus, 1.0);

    const cityFactors = defenseFactors(mountain, true);
    this.assertSize(cityFactors, 2);
    this.assertEqual(cityFactors[1].label, "City");
    this.assertApprox(cityFactors[1].bonus, 0.5);
  }

  test_defense_multiplier_adds_terrain_and_city_bonuses() {
    const forest = TERRAIN_TILES.find((t) => t.terrainType === "Forest");
    const mountain = TERRAIN_TILES.find((t) => t.terrainType === "Mountain");
    const plains = TERRAIN_TILES.find((t) => t.terrainType === "Land");
    this.assertApprox(defenseMultiplier(plains, false), 1.0);
    this.assertApprox(defenseMultiplier(forest, false), 1.33);
    this.assertApprox(defenseMultiplier(mountain, false), 2.0);
    this.assertApprox(defenseMultiplier(mountain, true), 2.5);
  }

  test_unit_defense_scales_the_base_stat() {
    const mountain = TERRAIN_TILES.find((t) => t.terrainType === "Mountain");
    this.assertApprox(unitDefense(100, mountain, false), 200);
    this.assertApprox(unitDefense(100, mountain, true), 250);
    this.assertApprox(unitDefense(100, null, false), 100);
  }

  test_terrain_defense_bonuses_match_the_spec() {
    const bonusOf = (type) => {
      const tile = TERRAIN_TILES.find((t) => t.terrainType === type);
      return tile ? tile.defenseBonus : 0;
    };
    this.assertApprox(bonusOf("Forest"), 0.33);
    this.assertApprox(bonusOf("Hills"), 0.33);
    this.assertApprox(bonusOf("Mountain"), 1.0);
    this.assertApprox(bonusOf("Land"), 0);
  }
}