jevtest¶
Plain-English end-to-end tests for Android and iOS apps. Write what a user does and what they should see; Jev works out the taps. Every run is recorded, so CI replays it exactly, offline.
app: build/app-debug.apk
device: { android: emulator-5554 }
tests:
- name: Sign in
fresh: true
steps:
- do: Sign in with email "${DEMO_EMAIL}" and password "${DEMO_PASSWORD}"
expect: The home screen is showing
see: Welcome, ${DEMO_EMAIL}
$ jevtest run login.yaml --lock frozen --out results
jevtest 0.10.0 · android · emulator-5554 · dev.jevtest.jevtest_demo · jev-1.13.0 · lockfile: frozen
▶ Sign in
✓ do: Sign in with email "${DEMO_EMAIL}" and password "${DEMO_PASSWORD}" (2.6s) — 3 saved steps
→ type "${DEMO_EMAIL}" into text_field 'Email'
→ type "${DEMO_PASSWORD}" into password_field 'Password'
→ tap button 'Sign in'
✓ expect: The home screen is showing — Jev 0.96
✓ see: Welcome, ${DEMO_EMAIL}
PASS Sign in (5.1s)
1/1 passed in 5s
Jev: 1 decision, 1 from lockfile, 0 asked live in 0.0s (0% of run time), $0.0000
Results: results/20260928-161344/android/emulator-5554
Real output from the demo app on an Android emulator. ${DEMO_PASSWORD} comes from .env: logs and reports only ever show the name.
Why jevtest¶
-
Tests read like the spec
One action, then what should be true.
do:takes a plain-English goal;tap:,type:,swipe:and 23 more are there when you want exact control. -
Deterministic by design
The first run saves the steps Jev worked out for each
do:, and its answers to every check, in a lockfile. Later runs repeat them exactly, with no network and no API key. -
Nothing assumed
No default device, no guessing what a typo meant, and settings with good defaults and strict limits. Anything missing or wrong fails before the run starts, and says exactly what to fix.
-
Real apps, real phones
Android emulators and phones, iOS simulators and iPhones. Native, Flutter, React Native, and in-app WebViews, all driven the same way. jevtest never turns off animations, and puts back what a step changes on the device (all but an Android emulator's location).
-
Wait until, or fail
Each step waits until what it needs is on screen, up to its timeout, and then fails saying what it waited for. No sleeps, no guessing when the app is "ready".
-
Built for CI
JUnit XML, a JSON report of every step and decision, screenshots of failures, one exit code. Split tests across several devices and run them at the same time.
How it works, in one picture¶
flowchart LR
A[Step: tap / see / do / expect] --> B[Wait until what it needs<br/>is on screen]
B --> C{do: with<br/>saved steps?}
C -- yes --> D[Repeat the saved steps]
C -- no --> E[Ask Jev<br/>choose from options] --> F[Act and save the step]
D --> G[Next step]
F --> GJev is TypeSafe's decision model: it reads text and chooses from the options jevtest gives it. It never writes free text, so what gets typed always comes from your test file. More on how it works.
Status¶
jevtest is new. It is tested end to end on a Flutter demo app with native and web screens, on Android emulators (API 37 and API 35), a Pixel 4a (Android 13), iOS simulators (iOS 26) and an iPhone 17 (iOS 27), and on six apps written to test it (SwiftUI, UIKit, Jetpack Compose, Android Views, React Native and a second Flutter app) on the emulators and simulators, the Android ones on the Pixel, and SwiftUI, UIKit and Flutter on the iPhone, with 100% line and branch coverage in its unit tests. Issues and pull requests are welcome.