chore: add linting (#259)

.eslintignore

@@ -0,0 +1,2 @@
+node_modules
+build

package.json

@@ -2,18 +2,19 @@
   "private": true,
   "repository": "https://github.com/tanstack/react-virtual.git",
   "scripts": {
+    "build": "yarn lint && rollup --config rollup.config.js && tsc -b",
+    "cipublish": "ts-node scripts/publish.ts",
+    "cipublishforce": "YARN_REGISTRY=https://registry.npmjs.org CI=true yarn cipublish",
+    "dev": "yarn watch",
     "linkAll": "lerna exec 'yarn link'",
-    "unlinkAll": "lerna exec 'yarn unlink'",
+    "lint": "eslint ./packages --ext .js,.ts,.tsx",
+    "prettier": "prettier \"packages/*/{src/**,examples/**/src/**}.{md,js,jsx,ts,tsx,json}\" --write",
     "test": "(is-ci && yarn test:ci) || yarn test:dev",
     "test:ci": "jest",
     "test:dev": "jest --watch",
-    "build": "rollup --config rollup.config.js && tsc -b",
-    "watch": "concurrently --kill-others \"rollup --config rollup.config.js -w\" \"tsc -b --watch\"",
-    "dev": "yarn watch",
-    "prettier": "prettier \"packages/*/{src/**,examples/**/src/**}.{md,js,jsx,ts,tsx,json}\" --write",
+    "unlinkAll": "lerna exec 'yarn unlink'",
     "visualize": "lerna exec 'open build/stats-html.html'",
-    "cipublish": "ts-node scripts/publish.ts",
-    "cipublishforce": "YARN_REGISTRY=https://registry.npmjs.org CI=true yarn cipublish"
+    "watch": "concurrently --kill-others \"rollup --config rollup.config.js -w\" \"tsc -b --watch\""
   },
   "workspaces": [
     "./packages/react-virtual"
@@ -29,16 +30,24 @@
     "@rollup/plugin-babel": "^5.3.0",
     "@rollup/plugin-node-resolve": "^13.1.3",
     "@rollup/plugin-replace": "^3.0.1",
+    "@testing-library/dom": "^8.11.3",
     "@testing-library/jest-dom": "^5.16.1",
     "@testing-library/react": "^12.1.2",
     "@testing-library/react-hooks": "^7.0.2",
+    "@testing-library/user-event": "14.0.0-beta.10",
     "@types/luxon": "^2.0.9",
     "@types/node": "^17.0.12",
     "@types/react": "^17.0.38",
+    "@typescript-eslint/eslint-plugin": "^5.11.0",
+    "@typescript-eslint/parser": "^5.11.0",
     "axios": "^0.25.0",
     "babel-plugin-transform-async-to-promises": "^0.8.18",
     "concurrently": "^7.0.0",
     "current-git-branch": "^1.1.0",
+    "eslint": "^8.8.0",
+    "eslint-config-prettier": "^8.3.0",
+    "eslint-plugin-jest": "^26.1.0",
+    "eslint-plugin-react-hooks": "^4.3.0",
     "git-log-parser": "^1.2.0",
     "jest": "^27.4.7",
     "lerna": "^4.0.0",

packages/react-virtual/package.json

@@ -39,5 +39,27 @@
   },
   "devDependencies": {
     "babel-plugin-transform-async-to-promises": "^0.8.18"
+  },
+  "eslintConfig": {
+    "parser": "@typescript-eslint/parser",
+    "plugins": [
+      "@typescript-eslint",
+      "jest"
+    ],
+    "extends": [
+      "eslint:recommended",
+      "plugin:@typescript-eslint/recommended",
+      "prettier",
+      "plugin:react-hooks/recommended",
+      "plugin:jest/recommended"
+    ],
+    "rules": {
+      "react-hooks/exhaustive-deps": [
+        "warn",
+        {
+          "additionalHooks": "(useIsomorphicLayoutEffect)"
+        }
+      ]
+    }
   }
 }

packages/react-virtual/src/index.tsx

@@ -18,9 +18,9 @@ interface ScrollToOptions {
   align: ScrollAlignment
 }
 
-interface ScrollToOffsetOptions extends ScrollToOptions {}
+type ScrollToOffsetOptions = ScrollToOptions
 
-interface ScrollToIndexOptions extends ScrollToOptions {}
+type ScrollToIndexOptions = ScrollToOptions
 
 export interface Range {
   start: number
@@ -358,8 +358,8 @@ const findNearestBinarySearch = (
   value: number,
 ) => {
   while (low <= high) {
-    let middle = ((low + high) / 2) | 0
-    let currentValue = getCurrentValue(middle)
+    const middle = ((low + high) / 2) | 0
+    const currentValue = getCurrentValue(middle)
 
     if (currentValue < value) {
       low = middle + 1
@@ -389,7 +389,7 @@ function calculateRange({
   const size = measurements.length - 1
   const getOffset = (index: number) => measurements[index].start
 
-  let start = findNearestBinarySearch(0, size, getOffset, scrollOffset)
+  const start = findNearestBinarySearch(0, size, getOffset, scrollOffset)
   let end = start
 
   while (end < size && measurements[end].end < scrollOffset + outerSize) {