Don't test sdist in the main script.

See haskell#3630 (comment).

travis-script.sh

@@ -40,8 +40,6 @@ cp cabal.project.travis cabal.project.local
 # Cabal
 # ---------------------------------------------------------------------
 
-export CABAL_BUILDDIR="${CABAL_BDIR}"
-
 # NB: Best to do everything for a single package together as it's
 # more efficient (since new-build will uselessly try to rebuild
 # Cabal otherwise).
@@ -70,18 +68,11 @@ timed cabal new-build Cabal Cabal:package-tests Cabal:unit-tests
 # Check for package warnings
 (cd Cabal && timed cabal check) || exit $?
 
-# Test that an sdist can be created
-(cd Cabal && timed cabal sdist --builddir=${CABAL_BDIR}) || exit $?
-
-unset CABAL_BUILDDIR
 
 # ---------------------------------------------------------------------
 # cabal-install
 # ---------------------------------------------------------------------
 
-# Setting the build directory here helps avoid sdist bugs.
-export CABAL_BUILDDIR="${CABAL_INSTALL_BDIR}"
-
 timed cabal new-build cabal-install:cabal \
                       cabal-install:integration-tests \
                       cabal-install:integration-tests2 \
@@ -98,9 +89,6 @@ timed cabal new-build cabal-install:cabal \
 (cd cabal-install && timed ${CABAL_INSTALL_SETUP} haddock --builddir=${CABAL_INSTALL_BDIR} ) || exit $?
 
 (cd cabal-install && timed cabal check) || exit $?
-(cd cabal-install && timed cabal sdist --builddir=${CABAL_INSTALL_BDIR}) || exit $?
-
-unset CABAL_BUILDDIR
 
 # Check what we got
 ${CABAL_INSTALL_BDIR}/build/cabal/cabal --version