fix: BinaryReader 64-bit endianness + base-class generic#20
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Two correctness bugs in BinaryReader surfaced by the parity audit: 1. ReadInt64/ReadUInt64 hardcoded BNReadLE64 (little-endian) instead of the endian-agnostic BNRead64, so a BinaryReader whose Endianness is set to BigEndian silently read little-endian 64-bit values. The 8/16/32-bit siblings and the explicit *LE/*BE variants are all correct; only the two endian-agnostic 64-bit readers were wrong. Mirrors Python's read64. 2. Copy-paste typo: BinaryReader derived from AbstractSafeHandle<Architecture> instead of <BinaryReader> (BinaryWriter correctly uses <BinaryWriter>). AbstractSafeHandle<T_SELF> implements IEquatable/IComparable by casting `other as T_SELF`, so two BinaryReader wrappers never compared equal and BinaryReader was not IEquatable<BinaryReader> — diverging from Python's handle-address __eq__/__hash__.
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Summary
Two correctness bugs in
BinaryReader, surfaced by the parity audit.1. 64-bit reads ignored the reader's
EndiannessReadInt64/ReadUInt64hardcodedBNReadLE64(little-endian) instead of the endian-agnosticBNRead64, so aBinaryReaderwhoseEndiannessis set toBigEndiansilently read little-endian 64-bit values. The 8/16/32-bit siblings and the explicit*LE/*BEvariants are all correct — only the two endian-agnostic 64-bit readers were wrong. (Python'sread64→BNRead64.)2. Wrong base-class generic broke equality
Copy-paste typo:
BinaryReader : AbstractSafeHandle<Architecture>instead of<BinaryReader>(BinaryWritercorrectly uses<BinaryWriter>).AbstractSafeHandle<T_SELF>implementsIEquatable/IComparableby castingother as T_SELF, so twoBinaryReaderwrappers never compared equal andBinaryReaderwas notIEquatable<BinaryReader>— diverging from Python's handle-address__eq__/__hash__.Verification
ReadInt64/ReadUInt64now honourEndianness.LittleEndianvsBigEndian(computed independently from the raw bytes);EqualsObjectOnSelfReturnsTrueproves the base-class generic is nowBinaryReader.