synopsis split across a line causing haddock failures

[juhp]

Another weird haddock failure in the Stackage Nightly build (which I could not reproduce locally:

Preprocessing library stm-conduit-2.6.1...
Warning: The documentation for the following packages are not installed. No
links will be generated to these packages: nats-1.1,
transformers-compat-0.4.0.4
target ‘conduits concurrently.’ is not a module name or a source file

‘conduits concurrently.’ comes from the Synopsis!

[snoyberg]

This also affects:

• aeson-casing
• groom

See #1030

[bergmark]

Also tasty-rerun when building LTS

Running Haddock for tasty-rerun-1.1.5...
Preprocessing library tasty-rerun-1.1.5...
Warning: The documentation for the following packages are not installed. No
links will be generated to these packages: nats-1, transformers-compat-0.4.0.4
target ‘runs’ is not a module name or a source file

[snoyberg]

A number of these Haddocks seem to have started building again, I'll remove the relevant expected failures.

[juhp]

So maybe we can close this now?

[snoyberg]

I'd say this still requires more research to figure out what's going on. I've looked into it a few times, and have a theory that somewhere along the way whitespace in the cabal file is getting corrupted somehow, but I have no idea exactly how that's happening or why it seems to fix itself after some time. I'll try to set aside a block of time to work on it today.

[juhp]

For LTS-3.20 build this happens for:

• blaze-builder-enumerator-0.2.1.0
• ghc-mtl-1.2.1.0
• bson-0.3.2.1
• hedis-0.6.9
• ref-fd-0.4

[juhp]

Actually I think mongoDB too.

I suspect the packages in question all have their synopsis split over a line
(I guess people do that because they can...).

[snoyberg]

I've been able to reproduce this from within the Docker image by just running cabal commands. I'm seeing if I can reproduce this with a matching Cabal/cabal-install version combo on my local system.

[snoyberg]

I discovered the problem, and it appears to be a bug in response file handling. Specifically, it appears that Cabal is not properly escaping the arguments added to the response file. Consider the following response file:

--prologue=dist/doc/html/tmp/haddock-prologue1804289383846930886.txt
--dump-interface=dist/doc/html/tmp/tmp.haddock
--package-name=tmp
--package-version=0.1.0.0
--verbosity=1
--html
--read-interface=file:///opt/ghc/7.10.2/share/doc/ghc/html/libraries/base-4.8.1.0,/opt/ghc/7.10.2/share/doc/ghc/html/libraries/base-4.8.1.0/base.haddock
--read-interface=file:///opt/ghc/7.10.2/share/doc/ghc/html/libraries/ghc-prim-0.4.0.0,/opt/ghc/7.10.2/share/doc/ghc/html/libraries/ghc-prim-0.4.0.0/ghc-prim.haddock
--read-interface=file:///opt/ghc/7.10.2/share/doc/ghc/html/libraries/integer-gmp-1.0.0.0,/opt/ghc/7.10.2/share/doc/ghc/html/libraries/integer-gmp-1.0.0.0/integer-gmp.haddock
--odir=dist/doc/html/tmp/
--title=tmp-0.1.0.0: this is the
package synopsis
--optghc=-fbuilding-cabal-package
--optghc=-O
--optghc=-outputdir
--optghc=dist/build
--optghc=-odir
--optghc=dist/build/tmp-10310
--optghc=-hidir
--optghc=dist/build/tmp-10310
--optghc=-stubdir
--optghc=dist/build/tmp-10310
--optghc=-i
--optghc=-idist/build
--optghc=-i.
--optghc=-idist/build/autogen
--optghc=-Idist/build/autogen
--optghc=-Idist/build
--optghc=-optP-D__HADDOCK_VERSION__=2162
--optghc=-optP-include
--optghc=-optPdist/build/autogen/cabal_macros.h
--optghc=-this-package-key
--optghc=tmp_JdaAODhQa7p5WhxMngbYYt
--optghc=-hide-all-packages
--optghc=-package-id
--optghc=base-4.8.1.0-4f7206fd964c629946bb89db72c80011
--optghc=-XHaskell2010
-B/opt/ghc/7.10.2/lib/ghc-7.10.2
Foo.hs

I'll open up an upstream bug report.

[snoyberg]

Note that the reason I did not reproduce this on my system is that this will only occur with haddock > 2.16.1, which we have in our Docker image, but not on my home system.

[juhp]

Thanks, maybe we can close this now then?
(Or should we keep this open to track the upstream issues?)

[snoyberg]

No, good catch, we can close this.