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Source is good. Now let's make the tests faster and better. 

Signed-off-by: Adam Rocska <adam.rocska@adams.solutions>
This commit is contained in:
Adam Rocska 2020-04-30 22:33:32 +02:00
parent 927efa97f7
commit 7bde17165c
1 changed files with 22 additions and 1 deletions
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23
Sources/MaxMindDBReader/ControlByte.swift
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@ -39,7 +39,28 @@ struct ControlByte {
let payloadSizeWholeBytes: Data = bytesAfterTypeSpecifyingBytes + Data(
count: 4 - bytesAfterTypeSpecifyingBytes.count
)
payloadSize = 29 + payloadSizeWholeBytes.withUnsafeBytes { $0.load(as: UInt32.self) }
/// (n=0;00) : 28 | 28
/// (n=1;01) : 29 |
/// (n=2;10) : 285 | 255 + 30
/// (n=3;11) : 65821 | 65535 + 286
/// ——————————————————————————————————————————————————
/// (n=0;00) : 28 | 28
/// (n=1;01) : 29 | 0 + f(n-1) + 1
/// (n=2;10) : 285 | 255 + f(n-1) + 1
/// (n=3;11) : 65821 | 65535 + f(n-1) + 1
/// ——————————————————————————————————————————————————
let val = (0..<numberOfAdditionalBytesToRead)
.map({ Int($0) })
.reduce(UInt32(28)) { previous, byteCount in
precondition(byteCount <= 4)
let payloadSizeBase = Data(repeating: 0b1111_1111, count: byteCount) +
Data(count: 4 - byteCount)
return (previous + 1) + payloadSizeBase.withUnsafeBytes { $0.load(as: UInt32.self) }
}
payloadSize = UInt32(val) + payloadSizeWholeBytes.withUnsafeBytes { $0.load(as: UInt32.self) }
}
self.type = type