AFAICT (apologies if I’ve missed something!) the spec is unclear about what happens to using
headers when the child is a relative import with its own using
headers.
The spec says that “the child import can reuse custom headers from the parent import if the child is a relative import”. The relevant judgement is:
path₀ </> path₁ = path₂
───────────────────────────────────────────────────────────────────────────────────────────────────────────
https://authority path₀ file₀ using headers </> . path₁ file₁ = https://authority path₂ file₁ using headers
but what is the relevant judgement for:
path₀ </> path₁ = path₂
───────────────────────────────────────────────────────────────────────────────────────────────────────────
https://authority path₀ file₀ using headers </> . path₁ file₁ using headers2 = ???
Should headers2 replace headers? Or should they be merged (presumably right-biased)?