The collapsed tool row showed "tool output (N chars)" where N was len() of the
raw unified diff — i.e. the diff blob's *byte* length (headers, @@, +/-/context
all counted), labelled "chars". That number corresponded to nothing the operator
cares about, and len() is bytes not characters.
- Summarise a write/edit by the diff's row count instead — "· diff (7 rows) —
^x to view" — matching exactly what the ^x modal reports. Non-diff output (the
defensive fallback) now counts runes, not bytes, so "N chars" is truthful.
Retire itoaLen (the byte-count-as-"len" footgun).
- Harden the (+a −b) line counts in diffSummary: guard the file header with the
trailing space ("+++ "/"--- "), so a changed line whose content starts with
"++"/"--" is counted instead of mistaken for a header. Apply the same guard in
parseUnifiedDiff so such a line is rendered (and counted) rather than dropped.
tool_summary_test.go covers the diff-row summary, the rune (not byte) count, and
the ++/-- content-line edge case.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
kami
4e4d7c186a