Dateien lesen und schreiben

# Read scores.txt: one "name,score" pair per line.
print("3 scores, average 82.3")
print("best: ada (90)")

from learnrun import run_main


def run_with(text):
    with open("scores.txt", encoding="utf-8") as f:
        original = f.read()
    with open("scores.txt", "w", encoding="utf-8") as f:
        f.write(text)
    try:
        return run_main().strip().splitlines()
    finally:
        with open("scores.txt", "w", encoding="utf-8") as f:
            f.write(original)


def test_given_file():
    """Die mitgelieferte Datei ergibt 3 Punktzahlen, Durchschnitt 82.3, beste ada"""
    got = run_main().strip().splitlines()
    assert got == ["3 scores, average 82.3", "best: ada (90)"], f"das Programm gab {got!r} aus"


def test_other_file():
    """Eine andere Datei ergibt ihre eigene Anzahl, ihren Durchschnitt und ihre Beste"""
    got = run_with("lin,70\nmo,95\n")
    assert got == ["2 scores, average 82.5", "best: mo (95)"], f"für lin,70 und mo,95 gab das Programm {got!r} aus"


def test_no_final_newline():
    """Eine Datei ohne Zeilenumbruch in der letzten Zeile funktioniert auch"""
    got = run_with("kim,60\nsam,61")
    assert got == ["2 scores, average 60.5", "best: sam (61)"], f"für kim,60 und sam,61 gab das Programm {got!r} aus"

ada,90
grace,85
alan,72

def save_lines(path: str, lines: list[str]) -> None:
    with open(path, "a", encoding="utf-8") as f:
        for line in lines:
            f.write(line)


def load_lines(path: str) -> list[str]:
    with open(path, encoding="utf-8") as f:
        return list(f)


if __name__ == "__main__":
    save_lines("todo.txt", ["milk", "eggs"])
    print(load_lines("todo.txt"))

from main import load_lines, save_lines


def test_file_text():
    """save_lines schreibt eine Zeile pro Eintrag, jede mit Zeilenumbruch am Ende"""
    save_lines("t1.txt", ["milk", "eggs"])
    with open("t1.txt", encoding="utf-8") as f:
        text = f.read()
    assert text == "milk\neggs\n", f"die Datei enthält {text!r}, erwartet war 'milk\\neggs\\n'"


def test_round_trip():
    """load_lines liefert genau das Gespeicherte zurück, auch Umlaute"""
    lines = ["Grüße", "tea for two", "42"]
    save_lines("t2.txt", lines)
    got = load_lines("t2.txt")
    assert got == lines, f"load_lines gab {got!r} zurück, erwartet war {lines!r}"


def test_replaces():
    """Erneutes Speichern ersetzt die alten Zeilen"""
    save_lines("t3.txt", ["old"])
    save_lines("t3.txt", ["new"])
    got = load_lines("t3.txt")
    assert got == ["new"], f"nach dem Speichern von ['old'] und dann ['new'] gab load_lines {got!r} zurück"