Changed TEST_DEPENDS pip install to install one package at a time

[radarhere]

In https://github.com/python-pillow/Pillow-wheels, TEST_DEPENDS="pytest pytest-cov numpy scipy". scipy depends on numpy, and so if you try to install scipy and numpy at the same time, you receive an error that numpy is not present - https://travis-ci.org/python-pillow/pillow-wheels/jobs/397965939#L4956. This is not normally the case - it would seem to be happening here because wheels do not yet exist for Python 3.7.

So instead, for this scenario, I suggest installing TEST_DEPENDS packages one at a time.

Note that this doesn't solve that pillow-wheels build completely, but it's a step in the right direction, and worthwhile as a change in it's own right.

[matthew-brett]

Does this work OK for every possible way of spelling a dependency?

[radarhere]

echo "Empty string"
TEST_DEPENDS=""
for TEST_DEPENDENCY in $TEST_DEPENDS; do
	echo "install" $TEST_DEPENDENCY
done

echo ""
echo "One package"
TEST_DEPENDS="a"
for TEST_DEPENDENCY in $TEST_DEPENDS; do
	echo "install" $TEST_DEPENDENCY
done

echo ""
echo "Several packages"
TEST_DEPENDS="a b==12.3 c~=1.4 d>=1,<2"
for TEST_DEPENDENCY in $TEST_DEPENDS; do
	echo "install" $TEST_DEPENDENCY
done

outputs

Empty string

One package
install a

Several packages
install a
install b==12.3
install c~=1.4
install d>=1,<2

So that all seems correct to me. Let me know if there is a use case I haven't considered.

[hugovk]

@matthew-brett We're due for a quarterly Pillow release today (python-pillow/Pillow#3154), it would be great to get multibuild updated so we could include Python 3.7 wheels.

Re:

• Add Python 3.7 python-pillow/pillow-wheels#90
• [WIP] Add Python 3.7 to the travis builds. python-pillow/pillow-wheels#86
• Release wheels for latest stable for Python 3.7 python-pillow/Pillow#3074

@radarhere, do you know if this change will fix python-pillow/pillow-wheels#90?

Thanks!

[radarhere]

@hugovk this only helps the macOS build in pillow-wheels, not the Linux builds.

The problem in the macOS build is really that there are no Python 3.7 wheels for numpy and scipy yet.

• This issue fixes https://travis-ci.org/python-pillow/pillow-wheels/jobs/397965939#L4956 - ModuleNotFoundError: No module named 'numpy' when installing scipy.
• After that, you get https://travis-ci.org/radarhere/pillow-wheels/builds/398466492#L9038 - error: library dfftpack has Fortran sources but no Fortran compiler found
• I tried fixing that with brew install gcc, and got https://travis-ci.org/radarhere/pillow-wheels/builds/398466486#L9186 - error: Command "/usr/local/bin/gfortran -Wall -g -ffixed-form -fno-second-underscore -arch i386 -arch x86_64 -I/Users/travis/build/radarhere/pillow-wheels/venv/lib/python3.7/site-packages/numpy/core/include -c -c scipy/integrate/mach/d1mach.f -o build/temp.macosx-10.6-intel-3.7/scipy/integrate/mach/d1mach.o" failed with exit status 1 and that's as far as I've gone.

[hugovk]

• Python 3.7 wheels for NumPy were added here: Please provide Python 3.7 wheels numpy/numpy#11418

• Python 3.7 wheels for SciPy requested here: Please provide Python 3.7 wheels scipy/scipy#8987

[hugovk]

Python 3.7 wheels for SciPy are now available: scipy/scipy#8987

[webknjaz]

Installing everything with one command is fine in most of the cases so I'd suggest having a toggle to turn on this behavior and have it turned off by default

[radarhere]

Okay. I have added a commit so that instead of splitting up the packages into separate install commands by each word, instead it splits into separate install commands by each line.

[webknjaz]

LGTM

[radarhere]

Note that I've since realised that newlines are not as convenient as I had presumed -
- TEST_DEPENDS="pytest pytest-cov numpy"$'\n'"scipy" is the simplest way to do this that I could find.

[webknjaz]

You can probably do smth like

- |
  TEST_DEPENDS="pytest pytest-cov numpy
  scipy"

Or even use mapping instead of sequence in yaml

env:
  TEST_DEPENDS: |
    'pytest pytest-cov numpy
     scipy'