Bug#921897: morse-simulator: FTBFS (Could not import extension sphinx.ext.pngmath)

[Santiago Vila]

Package: src:morse-simulator
Version: 1.4-4
Severity: serious
Tags: ftbfs

Dear maintainer:

I tried to build this package in buster but it failed:

--------------------------------------------------------------------------------
[...]
 debian/rules build-indep
dh build-indep --with python3
   dh_update_autotools_config -i
   debian/rules override_dh_auto_configure
make[1]: Entering directory '/<<PKGBUILDDIR>>'
dh_auto_configure -- -DBUILD_DOC_SUPPORT=ON -DPYTHON_EXECUTABLE=/usr/bin/python3 \
	 -DCPACK_DEBIAN_PACKAGE_DEPENDS=python3-all-dev -DPYMORSE_SUPPORT=ON
	cd obj-x86_64-linux-gnu && cmake -DCMAKE_INSTALL_PREFIX=/usr -DCMAKE_BUILD_TYPE=None -DCMAKE_INSTALL_SYSCONFDIR=/etc -DCMAKE_INSTALL_LOCALSTATEDIR=/var -DCMAKE_EXPORT_NO_PACKAGE_REGISTRY=ON -DCMAKE_FIND_PACKAGE_NO_PACKAGE_REGISTRY=ON "-GUnix Makefiles" -DCMAKE_VERBOSE_MAKEFILE=ON -DCMAKE_INSTALL_LIBDIR=lib/x86_64-linux-gnu -DBUILD_DOC_SUPPORT=ON -DPYTHON_EXECUTABLE=/usr/bin/python3 -DCPACK_DEBIAN_PACKAGE_DEPENDS=python3-all-dev -DPYMORSE_SUPPORT=ON ..
-- The C compiler identification is GNU 8.2.0
-- The CXX compiler identification is GNU 8.2.0
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done

[... snipped ...]

CMake Warning:
  Manually-specified variables were not used by the project:

    CMAKE_EXPORT_NO_PACKAGE_REGISTRY
    CMAKE_INSTALL_LIBDIR
    CMAKE_INSTALL_LOCALSTATEDIR
    CMAKE_INSTALL_SYSCONFDIR
    CPACK_DEBIAN_PACKAGE_DEPENDS


-- Build files have been written to: /<<PKGBUILDDIR>>/obj-x86_64-linux-gnu
make[1]: Leaving directory '/<<PKGBUILDDIR>>'
   debian/rules override_dh_auto_build
make[1]: Entering directory '/<<PKGBUILDDIR>>'
cp version.py obj-*/
dh_auto_build
	cd obj-x86_64-linux-gnu && make -j1
make[2]: Entering directory '/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu'
/usr/bin/cmake -S/<<PKGBUILDDIR>> -B/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu --check-build-system CMakeFiles/Makefile.cmake 0
/usr/bin/cmake -E cmake_progress_start /<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/CMakeFiles /<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/CMakeFiles/progress.marks
make -f CMakeFiles/Makefile2 all
make[3]: Entering directory '/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu'
make -f CMakeFiles/man.dir/build.make CMakeFiles/man.dir/depend
make[4]: Entering directory '/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu'
cd /<<PKGBUILDDIR>>/obj-x86_64-linux-gnu && /usr/bin/cmake -E cmake_depends "Unix Makefiles" /<<PKGBUILDDIR>> /<<PKGBUILDDIR>> /<<PKGBUILDDIR>>/obj-x86_64-linux-gnu /<<PKGBUILDDIR>>/obj-x86_64-linux-gnu /<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/CMakeFiles/man.dir/DependInfo.cmake --color=
Scanning dependencies of target man
make[4]: Leaving directory '/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu'
make -f CMakeFiles/man.dir/build.make CMakeFiles/man.dir/build
make[4]: Entering directory '/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu'
env PYTHONPATH=/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu:/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/src:/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/fakeenv:/<<PKGBUILDDIR>>/src:/<<PKGBUILDDIR>>/testing:/<<PKGBUILDDIR>>/bindings/pymorse/src/:$PYTHONPATH PYTHONDONTWRITEBYTECODE="morse" MORSESOURCE=/<<PKGBUILDDIR>> /usr/bin/python3 /usr/bin/sphinx-build -b man -c /<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/doc /<<PKGBUILDDIR>>/doc/man /<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/doc/man && /bin/gzip -f /<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/doc/man/*.1
Running Sphinx v1.8.3

Extension error:
Could not import extension sphinx.ext.pngmath (exception: No module named 'sphinx.ext.pngmath')
make[4]: *** [CMakeFiles/man.dir/build.make:60: CMakeFiles/man] Error 2
make[4]: Leaving directory '/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu'
make[3]: *** [CMakeFiles/Makefile2:140: CMakeFiles/man.dir/all] Error 2
make[3]: Leaving directory '/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu'
make[2]: *** [Makefile:144: all] Error 2
make[2]: Leaving directory '/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu'
dh_auto_build: cd obj-x86_64-linux-gnu && make -j1 returned exit code 2
make[1]: *** [debian/rules:27: override_dh_auto_build] Error 2
make[1]: Leaving directory '/<<PKGBUILDDIR>>'
make: *** [debian/rules:8: build-indep] Error 2
dpkg-buildpackage: error: debian/rules build-indep subprocess returned exit status 2
--------------------------------------------------------------------------------

(The above is just how the build ends and not necessarily the most relevant part)

The build was made in my autobuilder with "dpkg-buildpackage -A"
and it also fails here:

https://tests.reproducible-builds.org/debian/rb-pkg/unstable/amd64/morse-simulator.html

where you can get a full build log if you need it.

If this is really a bug in one of the build-depends, please use reassign and affects,
so that this is still visible in the BTS web page for this package.

Thanks.