Ink's render-border.ts computes each border edge's background from
border<Edge>BackgroundColor ?? borderBackgroundColor only — it never falls
back to the Box's own backgroundColor. vue-tui's colorizeEdge had an extra
`?? bgColor` fallback, so a Box with backgroundColor but no explicit border
background painted its background onto the border glyphs too.
Drop the fallback. Background still fills the inner content area; border
glyphs are now uncolored unless an explicit border background is set.
Tests rewritten to match Ink (per maintainer's align-to-Ink policy; see
.agents/docs/parity-ledger.md Decisions log):
- add failing-first repro "Box backgroundColor does not bleed onto border
glyphs (Ink parity)"
- "wrapped text preserves backgroundColor on every content line": assert
inner rows carry bg, border rows don't (height 4->5 so text fits)
- "Box background with border fills content area": snapshot updated so
border rows have no bg
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
Yunfei He
0c113a3063