{
    enum data = "QUJD";
    assert(data.decodeBase64 == "ABC");
}

{
    enum data = "QQ==";
    assert(data.decodeBase64 == "A");
}

{
    enum data = "YSBiIGMgZCBlIGYgZyBoIGkgaiBrIGwgbSBuIG8gcCBxIHIgcyB0IHUgdiB3IHggeSB6";
    assert(data.decodeBase64 == "a b c d e f g h i j k l m n o p q r s t u v w x y z");
}

{
    enum data = "LCAuIDsgLyBbICcgXSBcID0gLSAwIDkgOCA3IDYgNSA0IDMgMiAxIGAgfiAhIEAgIyAkICUgXiAmICogKCApIF8gKyB8IDogPCA+ID8=";
    assert(data.decodeBase64 == ", . ; / [ ' ] \\ = - 0 9 8 7 6 5 4 3 2 1 ` ~ ! @ # $ % ^ & * ( ) _ + | : < > ?");
}

{
    enum data = "AAA=";
    assert(data.decodeBase64 == "\x00\x00");
}

{
    enum data = "AAAABBCC";
    assert(data.decodeBase64 == "\x00\x00\x00\x04\x10\x82");
}

{
    enum data = "AA==";
    assert(data.decodeBase64 == "\x00");
}

{
    enum data = "AA/=";
    assert(data.decodeBase64 == "\x00\x0f");
}

void testFail(const(char)[] input) @safe pure
{
    bool thrown = false;
    try {
        ubyte[] decoded = input.decodeBase64;
    } catch (Exception t) {
        thrown = true;
    }

    assert(thrown);
}

testFail("===A");
testFail("A=");
testFail("AA=");
testFail("A=AA");
testFail("AA=A");
testFail("AA=A====");
testFail("=AAA");
testFail("AAA=QUJD");
// This fails because we don't allow extra padding (than what is necessary)
testFail("AA======");
// This fails because we don't allow padding before the end of the string (otherwise we'd have a side-channel)
testFail("QU==QUJD");
testFail("QU======QUJD");
// Invalid data that's out of the alphabet
testFail("!@##@@!@");