ttrpg-initiative-tracker/shared/tests/turn.temphp.test.js

// Temp HP: damage hits temp first, then regular.
// setTempHp replaces (no stacking). Healing regular HP ignores temp.
const shared = require('@ttrpg/shared');
const { makeParticipant, applyHpChange, setTempHp, addParticipant } = shared;
const { mockCtx } = require('./_helpers');

function setupEnc() {
  const { ctx } = mockCtx();
  return {
    enc: { id: 'enc1', name: 'TempEnc', participants: [], isStarted: false, isPaused: false, round: 0 },
    ctx,
  };
}

describe('temp HP', () => {
  test('setTempHp sets tempHp on participant', async () => {
    const { enc, ctx } = setupEnc();
    const p = makeParticipant({
      name: 'Hero', type: 'character', initiative: 10, maxHp: 20, currentHp: 20,
    });
    let e = await addParticipant(enc, p, ctx);
    e = await setTempHp(e, p.id, 5, ctx);
    expect(e.participants[0].tempHp).toBe(5);
  });

  test('setTempHp replaces existing temp (no stacking)', async () => {
    const { enc, ctx } = setupEnc();
    const p = makeParticipant({
      name: 'Hero', type: 'character', initiative: 10, maxHp: 20, currentHp: 20,
    });
    let e = await addParticipant(enc, p, ctx);
    e = await setTempHp(e, p.id, 5, ctx);
    e = await setTempHp(e, p.id, 3, ctx);
    expect(e.participants[0].tempHp).toBe(3);
  });

  test('setTempHp to 0 clears temp', async () => {
    const { enc, ctx } = setupEnc();
    const p = makeParticipant({
      name: 'Hero', type: 'character', initiative: 10, maxHp: 20, currentHp: 20,
    });
    let e = await addParticipant(enc, p, ctx);
    e = await setTempHp(e, p.id, 5, ctx);
    e = await setTempHp(e, p.id, 0, ctx);
    expect(e.participants[0].tempHp).toBe(0);
  });

  test('damage: temp absorbs before regular HP', async () => {
    const { enc, ctx } = setupEnc();
    const p = makeParticipant({
      name: 'Hero', type: 'character', initiative: 10, maxHp: 20, currentHp: 20,
    });
    let e = await addParticipant(enc, p, ctx);
    e = await setTempHp(e, p.id, 5, ctx);
    e = await applyHpChange(e, p.id, 'damage', 8, ctx);
    expect(e.participants[0].tempHp).toBe(0);
    expect(e.participants[0].currentHp).toBe(17);
  });

  test('damage less than temp: only temp reduced', async () => {
    const { enc, ctx } = setupEnc();
    const p = makeParticipant({
      name: 'Hero', type: 'character', initiative: 10, maxHp: 20, currentHp: 20,
    });
    let e = await addParticipant(enc, p, ctx);
    e = await setTempHp(e, p.id, 10, ctx);
    e = await applyHpChange(e, p.id, 'damage', 4, ctx);
    expect(e.participants[0].tempHp).toBe(6);
    expect(e.participants[0].currentHp).toBe(20);
  });

  test('heal: does not affect temp HP', async () => {
    const { enc, ctx } = setupEnc();
    const p = makeParticipant({
      name: 'Hero', type: 'character', initiative: 10, maxHp: 20, currentHp: 10,
    });
    let e = await addParticipant(enc, p, ctx);
    e = await setTempHp(e, p.id, 5, ctx);
    e = await applyHpChange(e, p.id, 'heal', 8, ctx);
    expect(e.participants[0].tempHp).toBe(5);
    expect(e.participants[0].currentHp).toBe(18);
  });

  test('damage exactly equals temp: temp gone, regular intact', async () => {
    const { enc, ctx } = setupEnc();
    const p = makeParticipant({
      name: 'Hero', type: 'character', initiative: 10, maxHp: 20, currentHp: 20,
    });
    let e = await addParticipant(enc, p, ctx);
    e = await setTempHp(e, p.id, 5, ctx);
    e = await applyHpChange(e, p.id, 'damage', 5, ctx);
    expect(e.participants[0].tempHp).toBe(0);
    expect(e.participants[0].currentHp).toBe(20);
  });

  test('makeParticipant: tempHp defaults to 0', async () => {
    const p = makeParticipant({
      name: 'Hero', type: 'character', initiative: 10, maxHp: 20, currentHp: 20,
    });
    expect(p.tempHp).toBe(0);
  });
});