Summary  
This chapter demonstrates how to use the str() function to convert non-string values into strings for concatenation in code.

General domain of usage  
Formatting printed output

import unittest

def _dynamic_test(test_case, condition, success_message, failure_message):
    if condition:
        test_case._testMethodName = success_message
        test_case.assertTrue(True, success_message)
    else:
        test_case._testMethodName = failure_message
        test_case.fail(failure_message)


class TestUserCode(unittest.TestCase):
    # Expected values based on the provided starter data
    EXP_AGE = 19
    EXP_HAS_ID = True
    EXP_TIER = "VIP"
    EXP_SEAT_NUMBER_STR = "023"
    EXP_ZONE = "A"
    EXP_SEAT_NUMBER = 23

    EXP_IS_ADULT = True
    EXP_CAN_ENTER = True
    EXP_VIP_PERK = True
    EXP_MEMBER_FASTLANE = False
    EXP_SEAT_OK = True
    EXP_ENTRY_GRANTED = True

    EXP_SUMMARY = (
        f"{EXP_TIER}-{EXP_SEAT_NUMBER_STR}-{EXP_ZONE} | "
        f"age={EXP_AGE} | enter={EXP_ENTRY_GRANTED} | "
        f"vip={EXP_VIP_PERK} | fastlane={EXP_MEMBER_FASTLANE}"
    )

    def test_age_is_declared(self):
        import user_code
        _dynamic_test(
            self,
            hasattr(user_code, "age"),
            "The `age` variable is declared.",
            "Expected `age` to be declared."
        )

    def test_has_id_is_declared(self):
        import user_code
        _dynamic_test(
            self,
            hasattr(user_code, "has_id"),
            "The `has_id` variable is declared.",
            "Expected `has_id` to be declared."
        )

    def test_conversions_values_and_types(self):
        import user_code
        try:
            age_ok = isinstance(user_code.age, int) and user_code.age == self.EXP_AGE
            has_id_ok = isinstance(user_code.has_id, bool) and user_code.has_id == self.EXP_HAS_ID
            condition = age_ok and has_id_ok
            failure = (
                f"Expected `age` to be int `{self.EXP_AGE}` and `has_id` to be bool `{self.EXP_HAS_ID}`, "
                f"but got `age={getattr(user_code, 'age', None)}` and `has_id={getattr(user_code, 'has_id', None)}`."
            )
        except Exception as e:
            condition = False
            failure = f"Could not validate `age` and `has_id` due to an error: {type(e).__name__}."
        _dynamic_test(
            self,
            condition,
            f"`age` is `{self.EXP_AGE}` (int) and `has_id` is `{self.EXP_HAS_ID}` (bool).",
            failure
        )

    def test_ticket_parts_declared(self):
        import user_code
        needed = ["tier", "seat_number_str", "zone", "seat_number"]
        missing = [v for v in needed if not hasattr(user_code, v)]
        _dynamic_test(
            self,
            len(missing) == 0,
            "Ticket parts variables are declared (`tier`, `seat_number_str`, `zone`, `seat_number`).",
            f"Expected these variables to be declared: {', '.join(missing) if missing else '(none)'}."
        )

    def test_ticket_parts_values(self):
        import user_code
        try:
            condition = (
                user_code.tier == self.EXP_TIER and
                user_code.seat_number_str == self.EXP_SEAT_NUMBER_STR and
                user_code.zone == self.EXP_ZONE and
                user_code.seat_number == self.EXP_SEAT_NUMBER
            )
            failure = (
                f"Expected tier/seat/zone/seat_number to be "
                f"`{self.EXP_TIER}`, `{self.EXP_SEAT_NUMBER_STR}`, `{self.EXP_ZONE}`, `{self.EXP_SEAT_NUMBER}`, "
                f"but got `{getattr(user_code, 'tier', None)}`, `{getattr(user_code, 'seat_number_str', None)}`, "
                f"`{getattr(user_code, 'zone', None)}`, `{getattr(user_code, 'seat_number', None)}`."
            )
        except Exception as e:
            condition = False
            failure = f"Could not validate ticket parts due to an error: {type(e).__name__}."
        _dynamic_test(
            self,
            condition,
            "Ticket parts parsed correctly.",
            failure
        )

    def test_rules_declared(self):
        import user_code
        names = ["is_adult", "can_enter", "vip_perk", "member_fastlane", "seat_ok", "entry_granted"]
        missing = [n for n in names if not hasattr(user_code, n)]
        _dynamic_test(
            self,
            len(missing) == 0,
            "All rule variables are declared.",
            f"Expected these rule variables to be declared: {', '.join(missing) if missing else '(none)'}."
        )

    def test_rules_values(self):
        import user_code
        try:
            condition = (
                user_code.is_adult == self.EXP_IS_ADULT and
                user_code.can_enter == self.EXP_CAN_ENTER and
                user_code.vip_perk == self.EXP_VIP_PERK and
                user_code.member_fastlane == self.EXP_MEMBER_FASTLANE and
                user_code.seat_ok == self.EXP_SEAT_OK and
                user_code.entry_granted == self.EXP_ENTRY_GRANTED
            )
            failure = (
                "Expected rules to be: "
                f"is_adult={self.EXP_IS_ADULT}, can_enter={self.EXP_CAN_ENTER}, vip_perk={self.EXP_VIP_PERK}, "
                f"member_fastlane={self.EXP_MEMBER_FASTLANE}, seat_ok={self.EXP_SEAT_OK}, entry_granted={self.EXP_ENTRY_GRANTED}, "
                f"but got: is_adult={getattr(user_code, 'is_adult', None)}, can_enter={getattr(user_code, 'can_enter', None)}, "
                f"vip_perk={getattr(user_code, 'vip_perk', None)}, member_fastlane={getattr(user_code, 'member_fastlane', None)}, "
                f"seat_ok={getattr(user_code, 'seat_ok', None)}, entry_granted={getattr(user_code, 'entry_granted', None)}."
            )
        except Exception as e:
            condition = False
            failure = f"Could not validate rules due to an error: {type(e).__name__}."
        _dynamic_test(
            self,
            condition,
            "Rules computed correctly.",
            failure
        )

    def test_summary_declared(self):
        import user_code
        _dynamic_test(
            self,
            hasattr(user_code, "summary"),
            "The `summary` variable is declared.",
            "Expected `summary` to be declared."
        )

    def test_summary_value(self):
        import user_code
        try:
            actual = user_code.summary
            condition = actual == self.EXP_SUMMARY
            failure = f"Expected `summary` to be `{self.EXP_SUMMARY}`, but got `{actual}`."
        except Exception as e:
            condition = False
            failure = f"Could not validate `summary` due to an error: {type(e).__name__}."
        _dynamic_test(
            self,
            condition,
            "Summary string computed correctly.",
            failure
        )


if __name__ == "__main__":
    unittest.main()


test_main.py

Pythonの主要なデータ型について確かな理解を身につけ、それらを効果的に扱う方法を学びます。数値、ブール値、文字列を実践的な演習や具体例を通じて探求します。基本的な操作を自信を持って行い、クリーンで効率的なPythonコードを書くための基礎的なスキルを養います。

Pythonにおける数値データ型の基本を学び、整数型および浮動小数点数型の扱い方を習得します。基本的な算術演算の習得、不変性の概念の探求、Pythonの組み込み関数やツールを用いた実践的な数値処理の経験を得ることができます。

真理値を表す数値データの特殊なサブタイプであるブール型データについて明確に理解します。最初は難しく感じるかもしれませんが、ブール型の習得は論理的かつ効率的なプログラムを書くために不可欠です。本セクションでは、実際のプログラミングシナリオにおいて自信を持ってブール論理を適用できるようサポートします。

文字列は、Pythonでテキストを扱うための手段を提供し、メッセージの表示からユーザー入力の処理まで幅広く利用されます。文字列の作成、変更、操作方法について効果的に学習します。文字列の理解は、対話的なプログラムの作成や、コードを通じて情報を明確に伝達するために不可欠です。

データ型を効果的に扱い、プログラムの正確性と一貫性を確保する方法を学びます。値を適切な型に変換し、比較前にテキストをクリーンアップし、数値演算とテキストフォーマットを分離します。また、欠損データを意図的に管理し、人が読みやすいテキストと生データ入力を区別して扱うことで、信頼性が高く一貫性があり、読みやすい結果を得る方法も習得します。

チャレンジ：アクセス＆チケット特典エンジン

解答