[Groff] handling of composing and combined Unicode characters

[Bruno Haible]

Hi,

Find attached two files find.vi.after-preconv and
find.vi.after-preconv-decomposed, containing two test cases:
  1) \[u1EBF] = 'e' \u0302 \u0301
  2) 'x' \u0302 \u0301 (no precomposed character in Unicode)

I call
   $ troff -mandoc -Tutf8 < find.vi.after-preconv[-decomposed]"

The expected behaviour of troff should be that it emits a composed glyph,
created by src/roff/troff/input.cpp:composite_glyph_name(), right?
In both cases the behaviour is different:
  1) find.vi.1:6: warning: can't find special character `u0065_0302_0301'
  2) find.vi.1:6: warning: can't find special character `u0302'
     find.vi.1:6: warning: can't find special character `u0301'

Is my assumption right?

Bruno

find.vi.after-preconv
Description: Troff document

find.vi.after-preconv-decomposed
Description: Troff document