mathiasandClaude Sonnet 5
625955e944
Round-1 review found a real regression: tightening Split's closing-fence
match to require a trailing newline (closing the "\n---extra" bypass)
also silently narrowed internal/frontmatter's own Lint/Fix behavior — a
document whose closing fence is literally the last bytes of the file
("---\ntitle: x\n---", no body at all) used to parse fine via this
package's private split, and now returns ok=false, contradicting this
PR's own "zero behavior change for Lint/Fix" claim. internal/api and
internal/mcp were unaffected (both already required the trailing newline
pre-consolidation), but cmd/frontmatterlint's Lint/Fix relied on the old,
looser acceptance.
Split now distinguishes "fence followed by a newline" (real body follows)
and "fence is the last bytes of the document" (no body, not a bypass
attempt) — both valid — from "fence followed by anything else" (the
actual bypass shape, still rejected). Regression test pins the
literal-EOF case; flip-tested to confirm it's load-bearing.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>