gitlab-org--gitlab-foss/spec/experiments/application_experiment_spec.rb

127 lines
3.7 KiB
Ruby

# frozen_string_literal: true
require 'spec_helper'
RSpec.describe ApplicationExperiment do
subject { described_class.new(:stub) }
describe "publishing results" do
it "tracks the assignment" do
expect(subject).to receive(:track).with(:assignment)
subject.publish(nil)
end
it "pushes the experiment knowledge into the client using Gon.global" do
expect(Gon.global).to receive(:push).with(
{
experiment: {
'stub' => { # string key because it can be namespaced
experiment: 'stub',
key: 'e8f65fd8d973f9985dc7ea3cf1614ae1',
variant: 'control'
}
}
},
true
)
subject.publish(nil)
end
end
describe "tracking events", :snowplow do
it "doesn't track if excluded" do
subject.exclude { true }
subject.track(:action)
expect_no_snowplow_event
end
it "tracks the event with the expected arguments and merged contexts" do
subject.track(:action, property: '_property_', context: [
SnowplowTracker::SelfDescribingJson.new('iglu:com.gitlab/fake/jsonschema/0-0-0', { data: '_data_' })
])
expect_snowplow_event(
category: 'stub',
action: 'action',
property: '_property_',
context: [
{
schema: 'iglu:com.gitlab/fake/jsonschema/0-0-0',
data: { data: '_data_' }
},
{
schema: 'iglu:com.gitlab/gitlab_experiment/jsonschema/0-3-0',
data: { experiment: 'stub', key: 'e8f65fd8d973f9985dc7ea3cf1614ae1', variant: 'control' }
}
]
)
end
end
describe "variant resolution" do
it "returns nil when not rolled out" do
stub_feature_flags(stub: false)
expect(subject.variant.name).to eq('control')
end
context "when rolled out to 100%" do
it "returns the first variant name" do
subject.try(:variant1) {}
subject.try(:variant2) {}
expect(subject.variant.name).to eq('variant1')
end
end
end
context "when caching" do
let(:cache) { ApplicationExperiment::Cache.new }
before do
cache.clear(key: subject.name)
subject.use { } # setup the control
subject.try { } # setup the candidate
allow(Gitlab::Experiment::Configuration).to receive(:cache).and_return(cache)
end
it "caches the variant determined by the variant resolver" do
expect(subject.variant.name).to eq('candidate') # we should be in the experiment
subject.run
expect(cache.read(subject.cache_key)).to eq('candidate')
end
it "doesn't cache a variant if we don't explicitly provide one" do
# by not caching "empty" variants, we effectively create a mostly
# optimal combination of caching and rollout flexibility. If we cached
# every control variant assigned, we'd inflate the cache size and
# wouldn't be able to roll out to subjects that we'd already assigned to
# the control.
stub_feature_flags(stub: false) # simulate being not rolled out
expect(subject.variant.name).to eq('control') # if we ask, it should be control
subject.run
expect(cache.read(subject.cache_key)).to be_nil
end
it "caches a control variant if we assign it specifically" do
# by specifically assigning the control variant here, we're guaranteeing
# that this context will always get the control variant unless we delete
# the field from the cache (or clear the entire experiment cache) -- or
# write code that would specify a different variant.
subject.run(:control)
expect(cache.read(subject.cache_key)).to eq('control')
end
end
end