[GHC] #15498: HPC: do notation marks () as non-covered

9 Aug 2018

      #15498: HPC: do notation marks () as non-covered
-------------------------------------+-------------------------------------
           Reporter:  tom-bop        |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:  8.6.1
          Component:  Code Coverage  |           Version:  8.2.1
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  Incorrect
  Unknown/Multiple                   |  error/warning at compile-time
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 With this Main.hs, the "()" in "pure ()" is marked by HPC as a non-covered
 expression:

 {{{#!hs
 foo :: IO ()
 foo = do
    _ <- putStrLn "Unimportant string"
    pure ()

 main :: IO ()
 main = do
    foo
    putStrLn "Unimportant #2"
 }}}

 Repro:
   - `ghc -fhpc Main.hs`
   - `./Main`
   - `hpc markup Main.tix`

 This is an admittedly small issue, but it can be valuable for a project to
 aspire to 100% code coverage and false negatives prevent us from getting
 there.

-- 
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15498
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