Can I multiply options in matrix.include[] with the env option? - travis-ci

Question

Given a fairly heterogenous matrix that looks like this:
matrix:
include:
- os: linux
compiler: gcc
env: PLATFORM=android ARCH=arm64-v8a
- os: linux
compiler: gcc
env: PLATFORM=linux ARCH=aarch64
- os: osx
compiler: clang
env: PLATFORM=darwin ARCH=x86_64 TEST=unit
- os: osx
compiler: clang
env: PLATFORM=ios ARCH=arm64
This would result in four builds. I'd like to multiply it by two with an additional environment variable TYPE=Debug/Release. What's the best way to achieve this effect? Consider that I've only shown four configurations but the real number of configurations is 15. I'm hoping I won't have to duplicate everything twice.
I've tried the following but it merely adds two more builds, it doesn't combine with the matrix:
env:
matrix:
- TYPE=Debug
- TYE=Release
Same with this:
env:
- TYPE=Debug
- TYE=Release

Answer 1

I am afraid you cannot.
There is no matrix expansion that you might expect on the top level does not happen in matrix.include.
The env key forms just one axis of the build matrix, and it is not possible to use different env values to construct a build matrix.
The only way to achieve what you need is adding four more jobs:
matrix:
include:
- os: linux
compiler: gcc
env: PLATFORM=android ARCH=arm64-v8a TYPE=Debug
- os: linux
compiler: gcc
env: PLATFORM=linux ARCH=aarch64 TYPE=Debug
- os: osx
compiler: clang
env: PLATFORM=darwin ARCH=x86_64 TEST=unit TYPE=Debug
- os: osx
compiler: clang
env: PLATFORM=ios ARCH=arm64 TYPE=Debug
- os: linux
compiler: gcc
env: PLATFORM=android ARCH=arm64-v8a TYPE=Release
- os: linux
compiler: gcc
env: PLATFORM=linux ARCH=aarch64 TYPE=Release
- os: osx
compiler: clang
env: PLATFORM=darwin ARCH=x86_64 TEST=unit TYPE=Release
- os: osx
compiler: clang
env: PLATFORM=ios ARCH=arm64 TYPE=Release
(Incidentally, where are you getting the number 15?)

Answer 2

I usually use a small python script with a (jinja) template included to generate my travis config.
#!/usr/bin/env python3
tpl = '''
script:
- some_stuff.bash
matrix:
include:
{%- for letter, number in vars %}
- env: TESTS={{number}} CONFIG={{letter}}
{%- endfor %}
'''
import os
import jinja2
from itertools import product
tpl = jinja2.Template(tpl)
ymlfn = os.path.join(os.path.dirname(__file__), '.travis.yml')
with open(ymlfn, 'wt') as yml:
yml.write(tpl.render(vars=product(['a', 'b'], range(5))))
extend example