migrate-to-e2e

Migrate a suite to e2e

A migration is never one change. Each session ports one slice, proves it, and leaves both suites green: the old runner keeps every test it had, and the new e2e tests pass beside it. A progress file, MIGRATION.md, records what moved, what is left, and why, so the next session, yours or another agent's, starts from it instead of from scratch. The user decides when an old test goes.

Two references do most of the work. Read them; do not restate them.

• The e2e skill for everything the runner does: .agents/skills/e2e/SKILL.md

once npx e2e init or npx skills add tester-army/e2e ran, or npx e2e guide <topic> from the installed package. Topics named below (setup, writing-tests, agent, mcp, running, debugging) are its reference files.

• The migration guide for the source runner, and the engine page it ports

to. The guide maps the runner's config, commands, and API to e2e, and says what e2e does not have yet (marked missing or "No equivalent") with today's workaround. Both ship in the installed package under node_modules/e2e/docs/ with the same paths as .mdx files.

Detect the source runner, then read both docs in its row in full, before the inventory and before writing any code. Each later step leans on them.

WebdriverIO and Appium have no guide. Map their WebDriver calls with the Selenium guide; map Appium's device commands with the Detox and Maestro guides, on the mobile engine. Tell the user the mapping is partial. A project with two source runners migrates one at a time, one section of the progress file each.

1. Resume or start

Look for MIGRATION.md beside the e2e config, then at the repo root. When one exists, this is a later session:

1. Read it, then the migration guide and engine page its Source line

names. Its Next section names the slice this session takes, unless the user names another.

1. Check it against the repo before trusting it: every ported test still

exists in both suites, every source file or test it lists still exists (except retired ones, deleted on purpose), and no new source file or test is missing from it (add those as todo). No Defect check: line: ask as in step 2. A planted bug noted under Next: revert it first (step 6).

1. Run the file's Run new command once. A ported test that fails now is

the first thing to fix, before any new slice.

1. Unless the progress file's Harness: line says done, go to step 3, Build

the harness. Otherwise go to step 4, Pick the slice.

No progress file means a first session: steps 2 and 3, then the rest.

2. Inventory the suite (first session)

Answer these from the repo; ask the user only what you cannot observe.

Write MIGRATION.md now (format in step 8), every source file todo.

Ask whether each slice should also run against a planted defect (step 6) and record the answer as Defect check: on or off.

3. Build the harness (once)

The harness is the config, the app launch, and one green test. It is done once and the progress file says so; later sessions skip this step.

1. No e2e config: npx e2e init --yes (topic setup). On a device project, swap

@e2e-dev/web for @e2e-dev/mobile and delete or rewrite the example test. One target per platform or browser the source suite covers.

1. Ask the user which model agent steps use, and configure it (topic

agent). A literal port needs none: every test can be deterministic, and a config without a model runs those.

1. Port the orchestration the CI job does, reusing the repo's own scripts

rather than writing new ones:

• The one process that serves the app (a dev server, Metro for an Expo dev

client) becomes the target's app.command with readyUrl (topic setup). The command gets only PATH, HOME, the temp-directory variables, and command.env, not the shell's environment, so pass what the server read from the old runner's environment in command.env.

• e2e has no services key. Databases, queues, and mock servers start

before the run with the command the CI job uses, or app.command runs a script that brings them up and then serves the app. Name the command in the progress file.

• A reset or seed the source ran per test (runScript with http.post,

cy.task('db:reset'), an API call in beforeEach) becomes fetch in a beforeEach or a fixture, so each test still starts from known data.

• A seed helper that imports the app's own code (an ORM factory, a

server module) is reused, not rewritten. The old runner may have compiled it to CommonJS; e2e loads every .ts file as an ES module. Importing it into a test can then fail with __dirname is not defined, with "does not provide an export named" for a CommonJS package, or with ERR_UNSUPPORTED_DIR_IMPORT. When it does, run the helper unchanged in a child process with the repo's own TypeScript runner (ts-node, tsx) and call it from a fixture. Do not edit the app's modules to make them load.

• Env values become module constants; passwords and tokens go under

credentials or secrets (topic setup). When the old config loaded an env file (dotenv.config()), load it the same way in the e2e config, so tests and helpers see the same values. app.command does not see them; pass the ones the server needs in command.env.

1. Port the simplest source test, often the sign-in or the launch, as the

smoke test. It must pass on every target before any other port. When it cannot, the harness is wrong, not the test: fix the harness.

1. init adds a test:e2e script (e2e run) unless a script already has

that name. When the name was taken, or init did not run, add one under a free name. Keep the old suite's scripts as they were.

1. Mark the harness done in the progress file, with the commands that start the

dependencies, run the old suite, and run the new one.

4. Pick the slice

A slice is what this session can finish green: one file, one folder, one tag, or one feature area, usually one to five tests. Ask the user which. When they leave it to you, suggest in this order:

1. Tests whose shared helpers are already ported.
2. Tests that break often in the old runner: retries, flaky history in CI,

comments explaining a workaround for the runner. They gain the most.

1. Tests that need a capability the guide marks missing or "No

equivalent", last.

Write the slice into the progress file's Next section before starting, so an interrupted session leaves a trail.

5. Port the slice

Port the slice's shared helpers first, once, as plain .ts files (not .e2e.ts, so the runner does not collect them), for example under tests/support/. A subflow becomes a function or a test.extend fixture; a page object becomes a fixture (topic writing-tests). Record each in the progress file.

Then each test, one at a time:

• Keep its title, and open the file with a comment naming the source

(// Ported from __e2e__/flows/login.yml), so reports and reviewers map one to the other.

• Translate literally first with the guide's tables, one awaited call per

source step. Each source assertion maps to its own e2e assertion. A wait that fails on timeout (waitForFunction) becomes one more, so the e2e count is at least the inventory's.

• A test the source skips is ported in full and stays skipped, with the

source's reason, so it can be turned back on in either suite. Its row says so; when the reason allows, run it unskipped once and note the result.

• Learn exact names before writing a locator: e2e mcp with open_session,

observe, and locate (topic mcp). When your client has no e2e MCP tools, run the test and read the screen listed on its trace page (topic debugging); do not build a bridge. The guide's notes on selectors list the edits most ports need: e2e matches whole strings and fails on several matches where the old runner took the first. When a query also matches a hidden copy (another layout's), add { visible: true }. When two visible nodes match, such as a second toast over the first, pick the one the step means.

• A sleep or fixed wait becomes an assertion on the state it waited for.
• A per-platform branch becomes { platforms: [...] } on a test, or an if

on the platform fixture inside one.

• A workaround the source comments explain (a flaky hideKeyboard, a

coordinate tap, a retry loop around a picker) is a workaround for the old runner. Try the plain step first; keep a workaround only when e2e needs it too, with its own comment saying why.

• Where the guide marks a step missing or "No equivalent", use its

workaround. When there is none, the test stays in the old runner: mark it stays with the reason and offer to send npx e2e feedback --type feature -m "<the gap>" once: preview it with --dry-run and send it only when the user agrees (the e2e skill, Feedback).

• Do not change app code. A test that needs a test id the app lacks gets

agent.act or a different locator; propose the app change to the user instead of making it. A defect check's planted bug (step 6) is the exception, reverted the same session.

agent.act comes after the literal port passes, never instead of it, and only with a model configured. Propose it for a stretch the source kept patching: coordinate taps, picker spins, long tap sequences through a wizard. Pin the outcome right after with a locator assertion (topic agent).

6. Prove each port

A port is done when it is as strict as the source and passes every time.

1. Run it on every target the source covered:

npx e2e run <file> --repeat-each 3, plus --no-cache when it has agent steps. Three of three on each target, or it is not done (topic running).

1. When the old suite can run here, run the source test on the same build.

A failure both runners show is an app or environment bug: report it, do not port around it. A failure only e2e shows is the port's.

1. Check strictness against the source: an e2e assertion for every source

assertion, so the count is at least the inventory's, and every end state the source checked is checked. Never weaken an assertion, widen a timeout without a reason, or drop a step to go green. A test that cannot pass honestly stays blocked with what failed.

1. Read the trace page of any failure before changing the test

(topic debugging).

Defect check (optional)

With Defect check: on, show both suites fail on the same bug:

1. With the user's agreement, plant a small bug in an end state the source

asserts (a checkout showing the wrong total), in a file with no uncommitted changes. Note the file under Next until it is reverted.

1. Rebuild, confirm the app shows the bug, then run Run old on the slice

(when it runs here) and npx e2e run <files> --no-cache.

1. Revert only that file (git checkout -- <file>), rebuild, and confirm

git diff -- <file> is empty.

1. Both fail at the step that checks the planted state: record it. Only

the old suite passes: record that the source was weaker. Only e2e passes: the port lost an assertion, so it is not done. Neither fails: pick another bug. A failure before that step is not a catch.

1. Fill the row's Defect check cell, for example total +1: both fail,

or old not run when the old suite cannot run here.

7. Run both suites

Until the user retires a source test, both runners keep it.

• Ported tests stay in the old suite too. Delete a source test only when the

user confirms, then mark it retired. Once neither a remaining source test nor e2e code uses a source helper, propose deleting it, and delete it when the user confirms.

• CI: propose adding the e2e suite beside the old job once a few ports are

green, and make the change only when the user agrees, since it edits the old runner's workflow. Reuse its build, services, and devices. Two runners never drive one device or simulator at the same time; run them one after the other in the same job, or give each its own device. The e2e job runs every ported test, so a later change that breaks one fails the pull request (topic running, Continuous integration).

• When the last source test is retired or marked stays, the progress file says

the migration is complete and which tests, if any, stay behind.

8. Keep the progress file

MIGRATION.md, beside the e2e config, is the migration's state. Update it as you go, not at the end; an interrupted session must leave it true.

# Migration to e2e

Source: Maestro, `__e2e__/flows/**` (guide: https://e2e.tester.army/docs/migrate/maestro.md, engine: https://e2e.tester.army/docs/mobile.md)
e2e: `e2e.config.ts`, tests `tests/**/*.e2e.ts`
Start dependencies: `pnpm e2e:mock-server`
Run old: `maestro test __e2e__`
Run new: `npx e2e run`
Harness: done, smoke `tests/login.e2e.ts` on ios and android
Defect check: on

| Source | e2e | Status | Assertions (source → e2e) | Passing | Defect check | Notes |
| --- | --- | --- | --- | --- | --- | --- |
| flows/login.yml | tests/login.e2e.ts | ported | 3 → 3 | ios 3/3, android 3/3 | wrong screen: both fail | |
| flows/create-account.yml | | blocked | 6 → | | | date picker spin fails on android, trace in .e2e/results |
| flows/search-screen.yml | | todo | 4 → | | | |

## Shared helpers

| Source | e2e | Used by |
| --- | --- | --- |
| setupApp.yml | tests/support/app.ts `openSignedOut()` | login, create-account |

## Gaps

- `addMedia` has no e2e equivalent (guide: missing); feedback sent.

## Next

flows/composer.yml and flows/composer-self-label.yml (both need `signInAlice()`).

One row per source file. A file whose tests end in different statuses gets one row per test, each with its own assertion count. A suite with hundreds of tests keeps file rows: the table is read at the start of every session.

Statuses: todo; ported (green in e2e, the source test still runs); retired (the user confirmed, the source test is deleted); blocked (tried, does not pass yet, with what failed); stays (stays in the old runner on purpose, with why).

9. Hand over

Tell the user what this session moved and what it proved: the tests ported and their pass counts per target, defect check results, the helpers ported, what is blocked or stays and why, the gaps reported, and the next slice. Ask which ported source tests may be retired. List every file you created or changed.

Rules

• One slice per session. Leave both suites green: the old suite passes as it

did, and every ported test passes.

• Never delete or edit a source test, helper, or the old runner's config

without the user's confirmation.

• Port from what the repo shows. Run every command you put in the

progress file at least once; one that cannot run here (the old runner not installed) says so in the progress file.

• A source step whose meaning is unclear, such as a tap on a disabled

control or a coordinate tap that may miss, keeps its intent in the port. Note your reading in the progress file and ask the user.

• One sentence from the e2e skill or the guide beats a paragraph of your

own. Name the topic or the guide's section.

• Never put a secret in a test, the config, or the progress file. Name the

credential (topic setup).

• Do not commit on the user's behalf.