Add Linting page for @codeceptjs/lint

docs/lint.md

@@ -0,0 +1,111 @@
+---
+permalink: /lint
+title: Linting
+---
+
+# Linting
+
+CodeceptJS tests have well-known smell patterns: fixed sleeps instead of waits, `if` branches that make tests non-deterministic, raw `fetch()` calls that bypass test steps and reports, plain-text passwords printed into logs, missing `await` on grabbers, and leftover `pause()` or `.only` from debugging sessions.
+
+[`@codeceptjs/lint`](https://github.com/codeceptjs/lint) catches all of them statically. It reads tests, page objects and helpers as an AST — CodeceptJS itself doesn't need to be installed and no browser is started.
+
+## Usage
+
+```bash
+npx @codeceptjs/lint                          # files from codecept.conf.js in the current directory
+npx @codeceptjs/lint tests/ pages/login.js    # explicit paths
+npx @codeceptjs/lint -r no-pause -r no-only   # only these rules (or --rules no-pause,no-only)
+npx @codeceptjs/lint rules                    # list all rules
+npx @codeceptjs/lint --json                   # findings as JSON
+npx @codeceptjs/lint -c e2e/codecept.conf.js  # config in another directory
+```
+
+Each finding is printed on one line:
+
+```
+checkout_test.js:4:3  error  no-fixed-wait  I.wait() sleeps unconditionally. Wait for a condition: I.waitForElement / I.waitForText / I.see
+```
+
+Exit codes: `0` — no errors (warnings allowed), `1` — errors found, `2` — bad input or a file that can't be parsed.
+
+Without paths, the linter reads `codecept.conf.js` (or `.ts`, `.cjs`, `.mjs`) and lints files matched by `tests`, local files from `include` (page objects, steps file) and helpers loaded with `require`.
+
+## Rules
+
+| Rule | Default | Detects |
+| --- | --- | --- |
+| `no-fixed-wait` | error | `I.wait(5)` with a number. Use `I.waitForElement`, `I.waitForText`, `I.see` |
+| `no-sleep` | error | `setTimeout`, including `window.setTimeout`, `await new Promise(r => setTimeout(r, ms))` and `timers/promises`, outside helpers |
+| `no-if-in-test` | error | `if` inside a Scenario or hook. Use `tryTo()` from `codeceptjs/effects` |
+| `no-fetch` | error | `fetch()` outside helpers. Use the REST helper: `I.sendGetRequest`, `I.sendPostRequest` |
+| `no-console` | warn | `console.*` outside helpers. Use `I.say()` |
+| `no-only` | error on CI, warn locally | `Scenario.only`, `Feature.only`, `Data(...).only` |
+| `no-pause` | error on CI, warn locally | `pause()` |
+| `no-skip` | warn | `Scenario.skip`, `Feature.skip`, `xScenario`, `xFeature` |
+| `secret-credentials` | error | `I.fillField` on a password, token, secret or API key field, or such a `process.env.*` passed to `I.*`, without `secret()` |
+| `await-grab` | error | `I.grab*()` assigned or used without `await` |
+| `no-actor-in-helper` | error | `I` inside a class extending `Helper`. Use `this.helpers[...]` |
+| `raw-browser-in-test` | warn | `I.use*To`, `I.executeScript` in a Scenario. Move it into a helper or page object |
+
+"On CI" means the `CI` environment variable is set, which every CI provider does. Locally `pause()` and `.only` stay warnings, so debugging stubs don't fail the lint.
+
+## Configuration
+
+Set rule levels in a `lint` section of `codecept.conf.js`:
+
+```js
+export const config = {
+  tests: './*_test.js',
+  lint: {
+    rules: { 'no-if-in-test': 'warn', 'raw-browser-in-test': 'off' },
+  },
+}
+```
+
+Levels are `error`, `warn` or `off`.
+
+To allow a single case, suppress it inline — the rule id is required:
+
+```js
+I.wait(1) // codeceptjs-lint-disable-line no-fixed-wait
+
+// codeceptjs-lint-disable-next-line no-fixed-wait
+I.wait(1)
+```
+
+TypeScript is read with Node's type stripping (Node 22.13+). Files that use `enum` or `namespace` are reported as parse errors. A TypeScript config that imports `.js` paths of `.ts` files (the tsx/esbuild convention) can't be loaded by plain Node; if the project has `tsx` installed, the linter registers its loader automatically, otherwise pass paths explicitly.
+
+## CI
+
+```yaml
+- run: npx @codeceptjs/lint
+- run: npx codeceptjs run
+```
+
+## Blocking Bad Edits by an AI Agent
+
+The linter can check an agent's edit before it lands. Add a `PreToolUse` hook to `.claude/settings.json`:
+
+```json
+{
+  "hooks": {
+    "PreToolUse": [
+      {
+        "matcher": "Write|Edit|MultiEdit",
+        "hooks": [{ "type": "command", "command": "npx @codeceptjs/lint --hook claude" }]
+      }
+    ]
+  }
+}
+```
+
+The hook checks only files the config lints. It builds the file as it would look after the edit, and blocks the edit only when it adds a new error. Errors already in the file and warnings never block, so an agent can still add a `pause()` stub or touch a legacy test. If the hook fails, the edit is allowed. See [Agentic Testing](/agents/) for the full agent toolkit.
+
+## API
+
+```js
+import Linter from '@codeceptjs/lint'
+
+const linter = await Linter.load('codecept.conf.js')
+for (const file of linter.files()) console.log(linter.lintFile(file))
+```