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An origin adapter turns byte requests into bounded aligned storage reads: cached blocks retain slice mappings while skipping origin reads · case 05

An origin adapter turns byte requests into bounded aligned storage reads: cached blocks retain slice mappings while skipping origin reads.

Member previewVariant 5 · 3 implementations · 7 checks per implementation

Case contract

x contains complete object length, positive storage block size, ordered [start,stop) requested spans already within object, and cached block numbers. Return [uncached-block-reads,request-to-block-slices]. Each storage read is [block,absolute-start,count], clipped at EOF. Request maps contain [block,offset,count] for every crossed block, including cached ones; empty spans map to an empty list. Storage reads are deduplicated and sorted by block.

Why this case matters

Range responses combine representation identity, conditional requests, framing, and partial-object state.

One recorded failure

Sample boundary fixture

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

Boundary fixture	Actual	Expected	Outcome
cached-block-fetch fixture 1	`[[[0, 0, 4], [2, 8, 2]], [[[2, 0, 2]], [[0, 0, 2]], [[0, 1, 2]]]]`	`[[[2, 8, 2]], [[[2, 0, 2]], [[0, 0, 2]], [[0, 1, 2]]]]`	Failed

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This record includes three runnable implementations, regression fixtures, execution results, and source hashes.

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