arc diff problems

[Edward Z. Yang]

And here's the existing bug report: https://secure.phabricator.com/T6050

Excerpts from Edward Z. Yang's message of 2015-08-05 12:53:47 -0700:
> OK, I've resolved the problem; the problem was that I had
> copypasted an updated commit message into the Phabricator
> description field which contained special fields, which caused
> problems for Phabricator.
> 
> Edward
> 
> Excerpts from Edward Z. Yang's message of 2015-08-05 11:06:59 -0700:
> > Hello friends,
> > 
> > I too am having Arcanist problems (my libphutil and arcanist
> > are at the latest head).  Here's my error:
> > 
> > [ezyang at hs01 ghc-quick]$ arc diff HEAD~
> > You have untracked files in this working copy.
> > 
> >   Working copy: /home/hs01/ezyang/ghc-quick/
> > 
> >   Untracked changes in working copy:
> >   (To ignore these changes, add them to ".git/info/exclude".)
> >     testsuite/tests/driver/T9938
> >     testsuite/tests/driver/T9938B
> >     testsuite/tests/driver/dynamicToo/dynamicToo001/d
> >     testsuite/tests/driver/dynamicToo/dynamicToo001/s
> >     testsuite/tests/driver/dynamicToo/dynamicToo005/A005.dyn_o-boot
> > 
> >     Ignore these untracked files and continue? [y/N] y
> > 
> > Exception
> > Field "testPlan" occurs twice in commit message!
> > (Run with `--trace` for a full exception trace.)
> > 
> > Here is the commit message in question:
> > 
> > commit 80ef08619c315e35e439e50724afc5d3b3203895
> > Author: Edward Z. Yang <ezyang at cs.stanford.edu>
> > Date:   Fri Jul 24 15:13:49 2015 -0700
> > 
> >     Unify hsig and hs-boot; add preliminary "hs-boot" merging.
> >     
> >     This patch drops the file level distinction between hs-boot and hsig;
> >     we figure out which one we are compiling based on whether or not there
> >     is a corresponding hs file lying around.
> >     
> >     To make the "import A" syntax continue to work for bare hs-boot
> >     files, we also introduce hs-boot merging, which takes an A.hi-boot
> >     and converts it to an A.hi when there is no A.hs file in scope.
> >     This will be generalized in Backpack to merge multiple A.hi files together;
> >     which means we can jettison the "load multiple interface files" functionality.
> >     
> >     This works automatically for --make, but for one-shot compilation
> >     we need a new mode: ghc --merge-requirements A will generate an A.hi/A.o
> >     from a local A.hi-boot file; Backpack will extend this mechanism further.
> >     
> >     Has Haddock submodule update to deal with change in msHsFilePath behavior.
> >     
> >         - This commit drops support for the hsig extension. Can
> >           we support it?  It's annoying because the finder code is
> >           written with the assumption that where there's an hs-boot
> >           file, there's always an hs file too.  To support hsig, you'd
> >           have to probe two locations.  Easier to just not support it.
> >     
> >         - #10333 affects us, modifying an hs-boot still doesn't trigger
> >           recomp.
> >     
> >         - See compiler/main/Finder.hs: this diff is very skeevy, but
> >           it seems to work.
> >     
> >         - This code cunningly doesn't drop hs-boot files from the
> >           "drop hs-boot files" module graph, if they don't have a
> >           corresponding hs file.  I have no idea if this actually is useful.
> >     
> >     Signed-off-by: Edward Z. Yang <ezyang at cs.stanford.edu>
> >     
> >     Test Plan: validate
> >     
> >     Reviewers: simonpj, austin, bgamari, spinda
> >     
> >     Subscribers: thomie
> >     
> >     Differential Revision: https://phabricator.haskell.org/D1098
> > 
> > It doesn't work even if I delete "Test Plan".
> > 
> > Edward