Game Developer Specialist

Illustrative preview: this representative editorial result is not a recorded runtime session.

task_id: PICKUP-DEV-1
artifact_id: PICKUP-RULE-FIXTURE
version: 1
status: COMPLETE_LOCAL
producer / recipient: game developer / fixture owner
objective / scope: Supply complete Python source and check source for the closed rule fixture; execution and game integration are outside this delivered scope.
inputs_and_sources: The request's score, stable-ID, snapshot and validation rules.
confirmed_decisions: Successful first collection awards one point; duplicate collection awards none; restoration validates before mutation.
recommendations_and_pending: Run the checks in the chosen Python environment; actual engine/scene integration needs a separate authorized project context.
criteria: PICK-1 first award, PICK-2 duplicate denial, SAVE-1 independent snapshot, SAVE-2 atomic validated restore
next_action: Fixture owner runs the supplied check source and records source/harness hashes and raw output.

Complete source, not executed:

class World:
    def __init__(self):
        self.score = 0
        self.collected = set()

    def pickup(self, pickup_id):
        if not isinstance(pickup_id, str) or not pickup_id:
            raise ValueError('pickup id must be a nonempty string')
        if pickup_id in self.collected:
            return False
        self.collected.add(pickup_id)
        self.score += 1
        return True

    def checkpoint(self):
        return {'score': self.score, 'collected': sorted(self.collected)}

    def restore(self, snapshot):
        if not isinstance(snapshot, dict):
            raise ValueError('snapshot must be a mapping')
        score = snapshot.get('score')
        ids = snapshot.get('collected')
        if type(score) is not int or score < 0:
            raise ValueError('invalid score')
        if not isinstance(ids, list):
            raise ValueError('invalid collected list')
        if any(not isinstance(x, str) or not x for x in ids):
            raise ValueError('invalid pickup id')
        validated = set(ids)
        if len(validated) != len(ids) or score != len(validated):
            raise ValueError('inconsistent snapshot')
        self.score, self.collected = score, validated

Separate check source, not executed:

w = World()
assert w.pickup('A') is True
assert w.pickup('A') is False and w.score == 1
saved = w.checkpoint()
saved['collected'].append('external')
assert w.collected == {'A'}
saved = w.checkpoint()
assert w.pickup('B') is True
w.restore(saved)
assert w.score == 1 and w.pickup('A') is False
before = w.checkpoint()
for invalid in [None, {'score': True, 'collected': ['A']},
                {'score': 2, 'collected': ['A', 'A']},
                {'score': 1, 'collected': ['']},
                {'score': 9, 'collected': ['A']}]:
    try:
        w.restore(invalid)
    except ValueError:
        pass
    else:
        raise AssertionError('invalid snapshot accepted')
    assert w.checkpoint() == before

Implementation receipt
Binding: These supplied source blocks only; no repository commit, file hash, Python version or executed harness binding was obtained.
Behavior: The authoritative collected set guards the award; checkpoint creates a fresh list; restore builds a validated temporary set before assignment.
Integration: No scene, collision, audio, animation or save-file I/O was requested or inspected.
Checks: PENDING; the assertions are planned writer self-checks. No command ran and no PASS or exit code is claimed.
Limits: This is rule-fixture source, not a playable engine build or independent acceptance. Production file formats, capacity limits and engine integration require their own project contract.