Add a config to experiments & rollouts to allow dependent experiments to
be flagged.
We're getting past the point where it's possible to reason about which
experiments need to be turned off if we disable some other experiment,
and so this provides some additional rollout safety.
Can be specified in both experiments and rollouts: experiments.yaml
makes the most sense and we should default to it, but rollouts.yaml lets
us put dependencies between internal & external dependencies internally
and that's gonna be a little useful.
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Co-authored-by: ctiller <ctiller@users.noreply.github.com>
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It introduces the following syntax:
The following would mark the experiment as broken on ios, false on
windows and debug on posix. If a platform is un-specified, the default
for that platform will be set to false. Refer to
test/core/experiments/fixtures/test_experiments_rollout.yaml for
examples which are tested.
- name: experiment_1
default:
ios: broken
windows: false
posix: debug
It also supports the already existing syntax and interprets it as just
specifying one default for all platforms.
Supported platform tags: ios, windows, posix
Adds a test for the experiments codegen. It updates the codegen to parse
test_experiments.yaml and test_experiments_rollouts.yaml files and
generate test_experiments.h and test_experiments.cc files along with an
experiments_test.cc file. The experiments test verifies the returned
value of IsExperimentEnabled with the expected value.