feuerwerk/tests/core/struct-variable.test.ts

import { describe, expect, it } from 'vitest';
import {
  AddStructFieldCommand,
  AddVariableCommand,
  RemoveStructFieldCommand,
  RenameStructFieldCommand,
} from '../../src/core/commands/variableCommands';
import { SetOverrideCommand } from '../../src/core/commands/sceneObjectCommands';
import { findAsset, objectHolders, type Project } from '../../src/core/model/Project';
import { coerceValue, variableDef } from '../../src/core/properties/PropertySchema';
import { makeBehavior, makeSpriteScene, place, roundTrip } from '../helpers';

const findObject = (project: Project, id: string) =>
  objectHolders(project)
    .flatMap((holder) => holder.objects)
    .find((o) => o.id === id);

const structDef = (project: Project, assetId: string, key: string) => {
  const asset = findAsset(project, assetId);
  const def = asset?.type === 'behavior' ? asset.variables.find((v) => v.key === key) : undefined;
  return def?.kind === 'struct' ? def : undefined;
};

/** A behavior with a struct variable `piece`, placed once with an override of its own. */
function withStruct() {
  const f = makeSpriteScene();
  const behavior = makeBehavior(f, 'B');
  f.stack.execute(new AddVariableCommand(behavior.id, 'piece', 'struct'));
  f.stack.execute(new AddStructFieldCommand(behavior.id, 'piece', { key: 'x', kind: 'number' }));
  const object = place(f, behavior.id, { x: 0, y: 0 });
  f.stack.execute(new SetOverrideCommand(f.sceneId, object, 'piece', { x: 7 }));
  return { f, behaviorId: behavior.id, object };
}

describe('a variable of type struct', () => {
  it('starts with no fields at all, so nothing is invented for it', () => {
    const f = makeSpriteScene();
    const behavior = makeBehavior(f, 'B');
    f.stack.execute(new AddVariableCommand(behavior.id, 'piece', 'struct'));
    expect(structDef(f.project, behavior.id, 'piece')?.fields).toEqual([]);
    expect(findAsset(f.project, behavior.id)?.props.piece).toEqual({});
  });

  it('grows a new field in the declaration, in its own value and in every override at once', () => {
    const { f, behaviorId, object } = withStruct();
    f.stack.execute(new AddStructFieldCommand(behaviorId, 'piece', { key: 'name', kind: 'text' }));

    expect(structDef(f.project, behaviorId, 'piece')?.fields).toEqual([
      { key: 'x', kind: 'number' },
      { key: 'name', kind: 'text' },
    ]);
    // The override deviates in `x` and must keep that while gaining the new field.
    expect(findObject(f.project, object)?.overrides.piece).toEqual({ x: 7, name: '' });
    expect(findAsset(f.project, behaviorId)?.props.piece).toEqual({ x: 0, name: '' });
  });

  it('takes the field back out on undo, so no value keeps a shape the declaration dropped', () => {
    const { f, behaviorId, object } = withStruct();
    f.stack.execute(new AddStructFieldCommand(behaviorId, 'piece', { key: 'name', kind: 'text' }));
    f.stack.undo();

    expect(structDef(f.project, behaviorId, 'piece')?.fields).toEqual([{ key: 'x', kind: 'number' }]);
    expect(findAsset(f.project, behaviorId)?.props.piece).toEqual({ x: 0 });
    expect(findObject(f.project, object)?.overrides.piece).toEqual({ x: 7 });
  });

  it('gives an override its own removed value back, not the default', () => {
    const { f, behaviorId, object } = withStruct();
    f.stack.execute(new RemoveStructFieldCommand(behaviorId, 'piece', 'x'));
    expect(findObject(f.project, object)?.overrides.piece).toEqual({});

    f.stack.undo();
    // 7 is the override's own value; the behavior's default for the same field is 0.
    expect(findObject(f.project, object)?.overrides.piece).toEqual({ x: 7 });
    expect(findAsset(f.project, behaviorId)?.props.piece).toEqual({ x: 0 });
  });

  it('carries the value along when a field is renamed, and back again on undo', () => {
    const { f, behaviorId, object } = withStruct();
    f.stack.execute(new RenameStructFieldCommand(behaviorId, 'piece', 'x', 'column'));

    expect(structDef(f.project, behaviorId, 'piece')?.fields).toEqual([{ key: 'column', kind: 'number' }]);
    expect(findObject(f.project, object)?.overrides.piece).toEqual({ column: 7 });

    f.stack.undo();
    expect(findObject(f.project, object)?.overrides.piece).toEqual({ x: 7 });
  });

  it('refuses a second field of the same name', () => {
    const { f, behaviorId } = withStruct();
    expect(() =>
      f.stack.execute(new AddStructFieldCommand(behaviorId, 'piece', { key: 'x', kind: 'text' })),
    ).toThrow(/already exists/);
  });

  it('survives saving and loading with its declaration, not just its value', () => {
    const { f, behaviorId, object } = withStruct();
    f.stack.execute(new AddStructFieldCommand(behaviorId, 'piece', { key: 'name', kind: 'text' }));

    const loaded = roundTrip(f.project);
    expect(structDef(loaded, behaviorId, 'piece')?.fields).toEqual([
      { key: 'x', kind: 'number' },
      { key: 'name', kind: 'text' },
    ]);
    expect(findObject(loaded, object)?.overrides.piece).toEqual({ x: 7, name: '' });
  });

  it('coerces a stored value to the shape its declaration promises', () => {
    const def = variableDef('piece', 'struct', undefined, undefined, [
      { key: 'x', kind: 'number' },
      { key: 'on', kind: 'boolean' },
    ]);
    // An unknown key is dropped, a missing one starts empty, and '3' is a number here.
    expect(coerceValue(def, { x: '3', gone: 9 })).toEqual({ x: 3, on: false });
  });
});