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A varint decoder accepts an ambiguous or overflowing frame · case 04

Trailing bytes, overlong encodings, and values larger than the specified integer width are accepted.

Member previewVariant 4 · 3 implementations · 9 checks per implementation

Case contract

Decode exactly one minimally encoded unsigned 32-bit LEB128 integer from bytes. Return None for an empty, unterminated, overlong, overflowing, or multi-value input; otherwise return the integer.

Why this case matters

Binary framing needs a single accepted representation and an exact consumption contract. Decoding a numeric prefix alone cannot establish that the whole frame was valid.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
overflow fifth group rejected	`5368709119`	`null`	Failed

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