Move Testing Library rules to live in the Jest config (#39)

* Move testing library rules into the jest config

* Add changesets

* Remove plugins array, testing-library/react already includes it

* Fix the check

* Fix the changeset

* Fix readme

.changeset/healthy-melons-argue.md

@@ -0,0 +1,7 @@
+---
+'@mels/eslint-config-jest': major
+---
+
+Move all Testing Library rules into this config.
+
+`eslint-config-jest` will check under the hood if `@testing-library/react` is installed by the consumer, and if so, then it will automatically enable the Testing Library rules.

.changeset/quiet-fans-deny.md

@@ -0,0 +1,5 @@
+---
+'@mels/eslint-config-react': major
+---
+
+Remove all Testing Library rules from this config. It now lives in [eslint-plugin-jest](https://github.com/melanieseltzer/toolkit/tree/main/packages/eslint-config-jest).

packages/eslint-config-jest/README.md

@@ -22,7 +22,11 @@
 
 ## ✨ Features
 
-This package contains all my Jest rules as an extensible shared ESLint config.
+This package contains all my Jest rules as an extensible shared ESLint config. It extends a number of configs as a base:
+
+- [eslint-plugin-jest](https://github.com/jest-community/eslint-plugin-jest) recommended rules
+- [eslint-plugin-jest](https://github.com/jest-community/eslint-plugin-jest) style rules
+- [eslint-plugin-testing-library](https://github.com/testing-library/eslint-plugin-testing-library/blob/main/lib/configs/react.ts) React rules (but only if this config detects that `@testing-library/react` is installed)
 
 ## Install
 

packages/eslint-config-jest/index.js

@@ -1,3 +1,19 @@
+const readPkgUp = require('read-pkg-up');
+
+const { packageJson } = readPkgUp.sync();
+
+let hasReactTestingLibrary = false;
+
+if (packageJson) {
+  const allDeps = Object.keys({
+    ...packageJson.peerDependencies,
+    ...packageJson.devDependencies,
+    ...packageJson.dependencies,
+  });
+
+  hasReactTestingLibrary = allDeps.includes('@testing-library/react');
+}
+
 const overrides = [
   {
     files: [
@@ -12,7 +28,10 @@ const overrides = [
 
       // https://github.com/jest-community/eslint-plugin-jest#rules
       'plugin:jest/style',
-    ],
+
+      // https://github.com/testing-library/eslint-plugin-testing-library/blob/main/lib/configs/react.ts
+      hasReactTestingLibrary ? 'plugin:testing-library/react' : null,
+    ].filter(Boolean),
 
     rules: {
       // https://github.com/jest-community/eslint-plugin-jest/blob/main/docs/rules/consistent-test-it.md
@@ -50,6 +69,16 @@ const overrides = [
 
       // https://github.com/jest-community/eslint-plugin-jest/blob/main/docs/rules/require-top-level-describe.md
       'jest/require-top-level-describe': 'warn',
+
+      ...(hasReactTestingLibrary
+        ? {
+            // https://github.com/testing-library/eslint-plugin-testing-library/blob/main/docs/rules/prefer-explicit-assert.md
+            'testing-library/prefer-explicit-assert': 'warn',
+
+            // https://github.com/testing-library/eslint-plugin-testing-library/blob/main/docs/rules/prefer-wait-for.md
+            'testing-library/prefer-wait-for': 'error',
+          }
+        : {}),
     },
   },
 ];

packages/eslint-config-jest/package.json

@@ -20,7 +20,9 @@
     "lint": "eslint ."
   },
   "dependencies": {
-    "eslint-plugin-jest": "^26.8.7"
+    "eslint-plugin-jest": "^26.8.7",
+    "eslint-plugin-testing-library": "^5.6.0",
+    "read-pkg-up": "^7.0.1"
   },
   "peerDependencies": {
     "@typescript-eslint/eslint-plugin": "^5.35.1",

packages/eslint-config-react/README.md

@@ -27,7 +27,6 @@ This package contains all my React-related rules as an extensible shared ESLint
 - React ([eslint-plugin-react](https://github.com/yannickcr/eslint-plugin-react))
 - React Hooks ([eslint-plugin-react-hooks](https://github.com/facebook/react/tree/main/packages/eslint-plugin-react-hooks))
 - JSX A11y (accessibility rules) ([eslint-plugin-jsx-a11y](https://github.com/jsx-eslint/eslint-plugin-jsx-a11y))
-- React Testing Library ([eslint-plugin-testing-library](https://github.com/testing-library/eslint-plugin-testing-library)) (if extended with `@mels/react/testing-library`)
 - JSX runtime config (if extended with `@mels/react/jsx-runtime`)
 
 ## Install
@@ -55,17 +54,6 @@ module.exports = {
 };
 ```
 
-If you're using [React Testing Library](https://testing-library.com/), this package also exports a `testing-library` config:
-
-```js
-// .eslintrc.js
-
-module.exports = {
-  extends: ['@mels/base', '@mels/react', '@mels/react/testing-library'],
-  // ... rest of config
-};
-```
-
 This package also exports a `jsx-runtime` config, if you're using the [new JSX transform from React 17](https://reactjs.org/blog/2020/09/22/introducing-the-new-jsx-transform.html#removing-unused-react-imports).
 
 ```js

packages/eslint-config-react/package.json

@@ -5,12 +5,10 @@
   "main": "./index.js",
   "exports": {
     ".": "./index.js",
-    "./testing-library": "./react-testing-library.js",
     "./jsx-runtime": "./jsx-runtime.js"
   },
   "files": [
     "index.js",
-    "react-testing-library.js",
     "jsx-runtime.js"
   ],
   "license": "MIT",
@@ -29,8 +27,7 @@
   "dependencies": {
     "eslint-plugin-jsx-a11y": "^6.6.1",
     "eslint-plugin-react": "^7.31.1",
-    "eslint-plugin-react-hooks": "^4.6.0",
-    "eslint-plugin-testing-library": "^5.6.0"
+    "eslint-plugin-react-hooks": "^4.6.0"
   },
   "peerDependencies": {
     "eslint": "^7.32.0 || ^8.0.0"

yarn.lock

@@ -4819,9 +4819,9 @@ eslint-plugin-testing-library@^5.0.1:
     "@typescript-eslint/utils" "^5.13.0"
 
 eslint-plugin-testing-library@^5.6.0:
-  version "5.6.0"
-  resolved "https://registry.yarnpkg.com/eslint-plugin-testing-library/-/eslint-plugin-testing-library-5.6.0.tgz#91e810ecb838f86decc9b5202876c87e42d73ea7"
-  integrity sha512-y63TRzPhGCMNsnUwMGJU1MFWc/3GvYw+nzobp9QiyNTTKsgAt5RKAOT1I34+XqVBpX1lC8bScoOjCkP7iRv0Mw==
+  version "5.6.3"
+  resolved "https://registry.yarnpkg.com/eslint-plugin-testing-library/-/eslint-plugin-testing-library-5.6.3.tgz#98878d3dbf4910f175d1ec0a3417ede147f3fc6e"
+  integrity sha512-//fhmCzopr8UDv5X2M3XMGxQ0j6KjKYZ+6PGqdV0woLiXTSTOAzuNsiTELGv883iCeUrYrnHhtObPXyiTMytVQ==
   dependencies:
     "@typescript-eslint/utils" "^5.13.0"