MIL-003: Step 2 - New flash cards

Review record RC-025 (Go, autonomous mode, not independent).

Task: MIL-003#1
Task: MIL-003#2
Task: MIL-003#3
Task: MIL-003#4
Task: MIL-003#5

tests/unit/domain/test_card.py

@@ -0,0 +1,38 @@
+"""Tests of the Card, LanguagePair and Vocabulary value types."""
+
+import dataclasses
+
+import pytest
+
+from flash_card.domain.entities.card import Card
+from flash_card.domain.entities.vocabulary import Vocabulary
+from flash_card.domain.value_objects.language_pair import LanguagePair
+
+
+def test_card_equals_card_with_same_texts() -> None:
+    assert Card("aku", "mig") == Card("aku", "mig")
+
+
+def test_card_is_frozen() -> None:
+    card = Card("aku", "mig")
+    with pytest.raises(dataclasses.FrozenInstanceError):
+        card.front = "kau"  # type: ignore[misc]
+
+
+def test_language_pair_holds_codes() -> None:
+    pair = LanguagePair("ms", "da")
+    assert (pair.front_code, pair.back_code) == ("ms", "da")
+
+
+def test_language_pair_is_frozen() -> None:
+    pair = LanguagePair("ms", "da")
+    with pytest.raises(dataclasses.FrozenInstanceError):
+        pair.front_code = "en"  # type: ignore[misc]
+
+
+def test_vocabulary_holds_pair_and_cards() -> None:
+    pair = LanguagePair("ms", "da")
+    cards = (Card("aku", "mig"),)
+    vocabulary = Vocabulary(pair, cards)
+    assert vocabulary.language_pair == pair
+    assert vocabulary.cards == cards

tests/unit/domain/test_deck.py

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+"""Tests of the Deck entity."""
+
+from collections.abc import Sequence
+
+import pytest
+
+from flash_card.domain.entities.card import Card
+from flash_card.domain.entities.deck import Deck
+from flash_card.domain.entities.vocabulary import Vocabulary
+from flash_card.domain.errors.vocabulary_errors import EmptyDeckError
+from flash_card.domain.value_objects.language_pair import LanguagePair
+
+PAIR = LanguagePair("ms", "da")
+A = Card("aku", "mig")
+B = Card("kau", "du")
+
+
+def _first(cards: Sequence[Card]) -> Card:
+    return cards[0]
+
+
+def test_from_vocabulary_holds_all_cards() -> None:
+    deck = Deck.from_vocabulary(Vocabulary(PAIR, (A, B)))
+    assert deck.cards == (A, B)
+    assert deck.language_pair == PAIR
+    assert len(deck) == 2
+
+
+def test_cards_returns_copy_when_deck_changes_later() -> None:
+    deck = Deck(PAIR, [A])
+    snapshot = deck.cards
+    deck.remove(A)
+    assert snapshot == (A,)
+    assert deck.is_empty
+
+
+def test_draw_returns_chosen_card() -> None:
+    assert Deck(PAIR, [A, B]).draw(_first) == A
+
+
+def test_draw_avoids_excluded_card_when_another_exists() -> None:
+    assert Deck(PAIR, [A, B]).draw(_first, exclude=A) == B
+
+
+def test_draw_returns_excluded_card_when_it_is_the_only_one() -> None:
+    assert Deck(PAIR, [A]).draw(_first, exclude=A) == A
+
+
+def test_draw_keeps_card_in_deck() -> None:
+    deck = Deck(PAIR, [A, B])
+    deck.draw(_first)
+    assert len(deck) == 2
+
+
+def test_draw_raises_when_deck_is_empty() -> None:
+    with pytest.raises(EmptyDeckError):
+        Deck(PAIR, []).draw(_first)
+
+
+def test_remove_deletes_first_equal_card() -> None:
+    deck = Deck(PAIR, [A, B, A])
+    deck.remove(A)
+    assert deck.cards == (B, A)
+
+
+def test_remove_raises_when_card_is_absent() -> None:
+    with pytest.raises(ValueError):
+        Deck(PAIR, [A]).remove(B)
+
+
+def test_is_empty_reflects_cards() -> None:
+    assert Deck(PAIR, []).is_empty
+    assert not Deck(PAIR, [A]).is_empty

tests/unit/domain/test_vocabulary_errors.py

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+"""Tests of the vocabulary error hierarchy."""
+
+import pytest
+
+from flash_card.domain.errors.vocabulary_errors import (
+    EmptyDeckError,
+    VocabularyError,
+    VocabularyFormatError,
+    VocabularyNotFoundError,
+)
+
+
+@pytest.mark.parametrize(
+    "error", [VocabularyFormatError, VocabularyNotFoundError, EmptyDeckError]
+)
+def test_error_is_a_vocabulary_error(error: type[VocabularyError]) -> None:
+    assert issubclass(error, VocabularyError)
+
+
+def test_vocabulary_error_is_an_exception() -> None:
+    assert issubclass(VocabularyError, Exception)