Battle-for-Tismo/tests/improvements_test.js

import { TestCase } from "./framework/test_case.js";
import { smallState, cityOf } from "./framework/helpers.js";
import { key } from "../shared/hex.js";
import { TRANSPORT_BY_ID } from "../shared/data/improvements.js";

const BIG_BUDGET = 10_000_000_000;

// A land tile owned by civ 0 that carries no transport improvement yet.
function bareOwnedLand(state, civ = 0) {
  return state.landCells.find((coords) => {
    const k = key(coords.x, coords.y);
    return state.civAt(coords) === civ && !state.roads.has(k) && !state.railways.has(k);
  });
}

export class ImprovementsTest extends TestCase {
  test_building_a_road_costs_money_and_lays_the_tile() {
    const state = smallState();
    state.budgets.set(0, BIG_BUDGET);
    const coords = bareOwnedLand(state);
    this.assertNotNull(coords, "the map has a bare owned land tile");
    const k = key(coords.x, coords.y);
    const before = state.getBudget(0);
    this.assertTrue(state.requestBuildImprovement(0, coords, "road"));
    this.assertTrue(state.roads.has(k), "the road is on the tile");
    this.assertFalse(state.railways.has(k), "it is not a railway");
    this.assertApprox(before - state.getBudget(0), TRANSPORT_BY_ID.road.buildCost);
  }

  test_a_railway_replaces_a_road_and_moves_twice_as_fast() {
    const state = smallState();
    state.budgets.set(0, BIG_BUDGET);
    const coords = bareOwnedLand(state);
    this.assertNotNull(coords);
    const k = key(coords.x, coords.y);
    const unit = state._spawnUnit(coords, 0, state.protoUnits[0]);

    state.roads.add(k);
    const roadHours = state._tileTravelHours(unit, coords);
    this.assertTrue(state.requestBuildImprovement(0, coords, "railway"));
    this.assertTrue(state.railways.has(k), "the railway is on the tile");
    this.assertFalse(state.roads.has(k), "the road was replaced");
    const railHours = state._tileTravelHours(unit, coords);
    this.assertApprox(railHours * 2, roadHours, 1e-9, "a railway is 50% faster than a road");
  }

  test_a_railway_moves_four_times_as_fast_as_open_grass() {
    const state = smallState();
    state.budgets.set(0, BIG_BUDGET);
    const coords = state.landCells.find(
      (c) => state.tiles[key(c.x, c.y)].terrainType === "Land" && state.civAt(c) === 0
    );
    this.assertNotNull(coords, "the map has owned grass");
    const unit = state._spawnUnit(coords, 0, state.protoUnits[0]);
    state.roads.delete(key(coords.x, coords.y));
    state.railways.delete(key(coords.x, coords.y));
    const open = state._tileTravelHours(unit, coords);
    this.assertTrue(state.requestBuildImprovement(0, coords, "railway"));
    const rail = state._tileTravelHours(unit, coords);
    this.assertApprox(rail * 4, open, 1e-9, "a railway is four times grass speed");
  }

  test_only_a_controlled_land_tile_may_be_improved() {
    const state = smallState();
    state.budgets.set(0, BIG_BUDGET);
    const sea = Object.keys(state.tiles)
      .map((k) => state.tiles[k])
      .find((tile) => tile.terrainClass === "Sea");
    this.assertNotNull(sea, "the map has a sea tile");
    // The exact coords of the sea tile.
    const seaEntry = Object.entries(state.tiles).find(([, tile]) => tile === sea);
    const [sx, sy] = seaEntry[0].split(",").map(Number);
    this.assertFalse(state.requestBuildImprovement(0, { x: sx, y: sy }, "road"), "no road at sea");

    // A tile owned by another civilisation is off limits.
    const foreign = state.landCells.find((c) => state.civAt(c) === 1);
    if (foreign) {
      this.assertFalse(
        state.requestBuildImprovement(0, foreign, "road"),
        "cannot build on a foreign tile"
      );
    }
    // An unknown improvement id is refused.
    const owned = bareOwnedLand(state);
    this.assertFalse(state.requestBuildImprovement(0, owned, "monorail"));
  }

  test_the_same_improvement_cannot_be_built_twice() {
    const state = smallState();
    state.budgets.set(0, BIG_BUDGET);
    const coords = bareOwnedLand(state);
    this.assertTrue(state.requestBuildImprovement(0, coords, "road"));
    const after = state.getBudget(0);
    this.assertFalse(state.requestBuildImprovement(0, coords, "road"), "already a road");
    this.assertApprox(state.getBudget(0), after, 1e-9, "nothing was charged");
  }

  test_poor_nations_cannot_build() {
    const state = smallState();
    state.budgets.set(0, 0);
    const coords = bareOwnedLand(state);
    this.assertFalse(state.requestBuildImprovement(0, coords, "road"));
    this.assertFalse(state.roads.has(key(coords.x, coords.y)));
  }

  test_maintenance_counts_roads_and_railways_the_nation_holds() {
    const state = smallState();
    state.budgets.set(0, BIG_BUDGET);
    const coords = bareOwnedLand(state);
    const k = key(coords.x, coords.y);
    const before = state.getTransportUpkeep(0);
    this.assertTrue(state.requestBuildImprovement(0, coords, "road"));
    this.assertApprox(
      state.getTransportUpkeep(0) - before,
      TRANSPORT_BY_ID.road.maintenance,
      1e-9,
      "a road adds its hourly maintenance"
    );
    this.assertTrue(state.requestBuildImprovement(0, coords, "railway"));
    this.assertApprox(
      state.getTransportUpkeep(0) - before,
      TRANSPORT_BY_ID.railway.maintenance,
      1e-9,
      "the railway replaces the road's maintenance"
    );
  }

  test_the_snapshot_ships_railways() {
    const state = smallState();
    state.budgets.set(0, BIG_BUDGET);
    const coords = bareOwnedLand(state);
    this.assertTrue(state.requestBuildImprovement(0, coords, "railway"));
    const snapshot = state.snapshot(0);
    this.assertTrue(
      snapshot.railways.some(([x, y]) => x === coords.x && y === coords.y),
      "the built railway is in the snapshot"
    );
    this.assertEqual(
      snapshot.versions.improvements,
      state._improvementVersion,
      "the improvement version is shipped"
    );
  }

  test_a_city_starts_with_a_road_the_player_could_upgrade() {
    const state = smallState();
    state.budgets.set(0, BIG_BUDGET);
    const city = cityOf(state, 0);
    const coords = { x: city.coords.x, y: city.coords.y };
    const k = key(coords.x, coords.y);
    this.assertTrue(state.roads.has(k), "a city carries a road");
    this.assertTrue(state.requestBuildImprovement(0, coords, "railway"));
    this.assertTrue(state.railways.has(k), "the city road becomes a railway");
    this.assertFalse(state.roads.has(k));
  }
}