From @masak

<masak> rakudo​: class A { has $!b is readonly = "foo" }; A.new
<p6eval> rakudo 55f51d​: ( no output )
<masak> locally, "No applicable candidates found to dispatch to for
'trait_mod​:is'"
<masak> should that work?
<jnthn> masak​: Probably...
* masak submits rakudobug
<masak> at least the warning is LTA-ly suspicious.
<jnthn> Well, it's not far off the mark.
<masak> it makes it sound as if 'is readonly' is not implemented...
<jnthn> Right, which in that case it evidently isn't. :-)
<masak> so, to summarize​: the bug is that 'is readonly' isn't implemented.
<masak> we also don't really know whether it should work,
semantically, to assign to a readonly variable during object
construction.

From @coke

08​:44 < timotimo> triage mode engaged​:
  https://rt-archive.perl.org/perl6/Public/Bug/Display.html?id=71356 -
  this bug seems resolved. can be closed.

Marking testneeded.

--
Will "Coke" Coleda

@coke - Status changed from 'new' to 'open'

From @timo

A test case for this bug was added to roast in this commit​:

Raku/roast@1fa9ddf
8b67d

From @stmuk

On Tue Dec 11 11​:27​:59 2012, timo wrote​:

A test case for this bug was added to roast in this commit​:

Raku/roast@1fa9ddf

I notice this warns with "useless use of 'is readonly' on $!attr"
and the test is still #?rakudo todo 'readonly attributes'

From @zoffixznet

As was discussed at http://irclog.perlgeek.de/perl6/2016-07-06#i_12795183 this feature/tests are no longer relevant in the current Rakudo implementation.

@zoffixznet - Status changed from 'open' to 'resolved'