Bug #15980
closedCoverage shows while/until after raise if/unless as uncovered line
Description
The following code shows line 2 (while true
) as uncovered:
raise if 1 == 2
while true
break
end
Coverage reports the following for this file: [1, 0, 1, nil]
. Note that true
isn't important, any while
condition will work. However, if you change line 1 to raise if false
, line 1 shows nil
coverage, and line 2 shows as covered ([nil, 1, 1, nil]
). That leads me to believe this issue is related to the optimizer.
I bisected this to 100bf2757468439106775a7d95a791a8c10b874a, which certainly appears related.
This is not a theoretical case, it affected three lines in Sequel. While not a major problem, I do think a fix should be backported to 2.6.
Note that this only affects line coverage. Branch coverage shows:
{"file.rb"=>
{:branches=>
{[:if, 0, 1, 0, 1, 15]=>
{[:then, 1, 1, 0, 1, 5]=>0, [:else, 2, 1, 0, 1, 15]=>1},
[:while, 3, 2, 0, 4, 3]=>{[:body, 4, 3, 2, 3, 7]=>1}}}}
If you run with both branch and line coverage, line coverage shows correctly.
This affects while
/until
after a line with raise ... if ...
or raise ... unless ...
. If you switch to if ...; raise ...; end
, then line coverage shows correctly.