FA-75750 / Text diff and three-way merge / Member archive

Unified hunk parser: an omitted old count is read as zero · case 05

Single-line hunks are rejected as truncated or misread.

Member previewVariant 5 · 3 implementations · 8 checks per implementation

Case contract

Parse "@@ -a[,b] +c[,d] @@" hunks (omitted counts are 1) and consume body lines until both remaining counts reach zero: " " (or a completely empty line) counts for both sides, "-" for old, "+" for new, "\\" marker lines are skipped and not counted, anything else ends the body. Remaining counts other than zero yield {"error": "hunk k truncated"}. Return [a, b, c, d, body_lines] per hunk.

Why this case matters

Patch tools must validate hunk bodies against their headers before applying anything.

One recorded failure

Sample boundary fixture

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

Boundary fixture	Actual	Expected	Outcome
omitted counts mean one	`{"error": "hunk 0 truncated"}`	`{"hunks": [[4, 1, 4, 1, 2]]}`	Failed

MEMBER ARCHIVE

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