On Sun, 28 May 2017 00:08:18 -0700, sml...@gmail.com wrote: > This bug is still present in > > This is Rakudo version 2017.05-134-g0c5fe56cc built on MoarVM version > 2017.05-25-g62bc54e9 > implementing Perl 6.c.
OK, keeping in mind that I have entirely, absolutely no idea what I am doing... I figured out that the block inside the string inside the parens is being annotated to a statement ID one greater than that of the whole statement_mod, which means it doesn't get "migrated". I also figured out that it seems to be the case that no blocks from inside the predicate of the for/given appear in the list considered for migration. I don't know if the annotation is correct or not, and I don't know if there is some contorted syntax that could put a block in the list of considered items for migration which would be erroneously migrated, but simply changing make_topic_block_ref to also grab all in_stmt_mod blocks with a statement ID higher than the one it is handed seems to pass all spectests and "fix" this problem. Resulting in the following one-character patch (drumroll please): diff --git a/src/Perl6/Actions.nqp b/src/Perl6/Actions.nqp index 36fa59b2b..6576f61b7 100644 --- a/src/Perl6/Actions.nqp +++ b/src/Perl6/Actions.nqp @@ -8953,7 +8953,7 @@ class Perl6::Actions is HLL::Actions does STDActions { $*W.pop_lexpad(); if nqp::defined($migrate_stmt_id) { migrate_blocks($*W.cur_lexpad(), $block, -> $b { - !$b.ann('in_stmt_mod') && ($b.ann('statement_id') // -1) == $migrate_stmt_id + !$b.ann('in_stmt_mod') && ($b.ann('statement_id') // -1) >= $migrate_stmt_id }); } ($*W.cur_lexpad())[0].push($block); Now, all that said, I cannot begin to properly emphasize the massive extent of the heck of which I do not know here. So, this is either the right fix, or a very wrong fix which might just break things in a way roast test writers are just not twisted and deviant enough to think of, or a fix that doesn't catch derivative cases, or... Other cases tested with this patch: $ perl6 -e 'say ("{$_}") given <aa bb>' aa bb $ perl6 -e 'say ("{$_}") if True given <aa bb>' aa bb $ perl6 -e 'say ("{$_}") if ({True}) given <aa bb>' aa bb $ perl6 -e 'say ("{$_}") if ("{True}") given <aa bb>' aa bb $ perl6 -e 'say ("{$_}") if "{True}" given <aa bb>' aa bb $ perl6 -e 'say ("{$_}") if "{so $_}" given <aa bb>' aa bb $ perl6 -e 'say ("{$_}") if ("{$_ ~~ /bb/ ?? q|1| !! q|| }") for <aa bb>' bb $ perl6 -e 'say ("{$_}") for ("{$_}" for <aa bb>)' aa bb $ perl6 -e 'my $a = 13; say ("{$_}") for {my $a = 42; ("{$a}" for <aa bb>)}()' 42 42