Skip to main content

Usage with Maestro

For instance, if you're using Maestro, you can measure the startup performance of the Twitter app:

  1. Create a twitter.yaml file:
appId: com.twitter.android
---
- launchApp
- assertVisible: Search and Explore
  1. Measure performance 🚀
flashlight test --bundleId com.twitter.android \
  --testCommand "maestro test twitter.yaml" \
  --duration 10000 \
  --resultsFilePath results.json
  1. Open the report
flashlight report results.json

Getting a meaningful TTI

Maestro can be slow to start and stop. Since Flashlight times the execution of the test command, the measured test runtime might not be so meaningful.

We have a forked version of Maestro which helps with that, here's the PR that implements the missing features.

Start a Maestro session in one terminal:

npx @perf-profiler/maestro@latest start-session

Then replace maestro test by npx @perf-profiler/maestro@latest test for instance

flashlight test --bundleId com.twitter.android \
  --testCommand "npx @perf-profiler/maestro@latest test twitter.yaml" \
  --duration 10000 \
  --resultsFilePath results.json

"Average test runtime" will now measure the time from start of the app to the appearance of "Search & explore", so quite close to a TTI.