support eslint with typescript

.babelrc

@@ -7,6 +7,7 @@
           "node": "10"
         }
       }
-    ]
+    ],
+    "@babel/preset-typescript"
   ]
-}
+}

.eslintrc

@@ -12,5 +12,20 @@
   },
   "env": {
     "browser": true
-  }
+  },
+  "overrides": [
+    {
+      "files": "**/*.+(ts|tsx)",
+      "parser": "@typescript-eslint/parser",
+      "parserOptions": {
+        "project": "./tsconfig.json"
+      },
+      "plugins": ["@typescript-eslint/eslint-plugin"],
+      "extends": [
+        "plugin:@typescript-eslint/eslint-recommended",
+        "plugin:@typescript-eslint/recommended",
+        "eslint-config-prettier/@typescript-eslint"
+      ]
+    }
+  ]
 }

package-lock.json

@@ -110,6 +110,20 @@
         "@babel/types": "^7.7.0"
       }
     },
+    "@babel/helper-create-class-features-plugin": {
+      "version": "7.7.0",
+      "resolved": "https://registry.npmjs.org/@babel/helper-create-class-features-plugin/-/helper-create-class-features-plugin-7.7.0.tgz",
+      "integrity": "sha512-MZiB5qvTWoyiFOgootmRSDV1udjIqJW/8lmxgzKq6oDqxdmHUjeP2ZUOmgHdYjmUVNABqRrHjYAYRvj8Eox/UA==",
+      "dev": true,
+      "requires": {
+        "@babel/helper-function-name": "^7.7.0",
+        "@babel/helper-member-expression-to-functions": "^7.7.0",
+        "@babel/helper-optimise-call-expression": "^7.7.0",
+        "@babel/helper-plugin-utils": "^7.0.0",
+        "@babel/helper-replace-supers": "^7.7.0",
+        "@babel/helper-split-export-declaration": "^7.7.0"
+      }
+    },
     "@babel/helper-create-regexp-features-plugin": {
       "version": "7.7.2",
       "resolved": "https://registry.npmjs.org/@babel/helper-create-regexp-features-plugin/-/helper-create-regexp-features-plugin-7.7.2.tgz",
@@ -425,6 +439,15 @@
         "@babel/helper-plugin-utils": "^7.0.0"
       }
     },
+    "@babel/plugin-syntax-typescript": {
+      "version": "7.3.3",
+      "resolved": "https://registry.npmjs.org/@babel/plugin-syntax-typescript/-/plugin-syntax-typescript-7.3.3.tgz",
+      "integrity": "sha512-dGwbSMA1YhVS8+31CnPR7LB4pcbrzcV99wQzby4uAfrkZPYZlQ7ImwdpzLqi6Z6IL02b8IAL379CaMwo0x5Lag==",
+      "dev": true,
+      "requires": {
+        "@babel/helper-plugin-utils": "^7.0.0"
+      }
+    },
     "@babel/plugin-transform-arrow-functions": {
       "version": "7.2.0",
       "resolved": "https://registry.npmjs.org/@babel/plugin-transform-arrow-functions/-/plugin-transform-arrow-functions-7.2.0.tgz",
@@ -721,6 +744,17 @@
         "@babel/helper-plugin-utils": "^7.0.0"
       }
     },
+    "@babel/plugin-transform-typescript": {
+      "version": "7.7.2",
+      "resolved": "https://registry.npmjs.org/@babel/plugin-transform-typescript/-/plugin-transform-typescript-7.7.2.tgz",
+      "integrity": "sha512-UWhDaJRqdPUtdK1s0sKYdoRuqK0NepjZto2UZltvuCgMoMZmdjhgz5hcRokie/3aYEaSz3xvusyoayVaq4PjRg==",
+      "dev": true,
+      "requires": {
+        "@babel/helper-create-class-features-plugin": "^7.7.0",
+        "@babel/helper-plugin-utils": "^7.0.0",
+        "@babel/plugin-syntax-typescript": "^7.2.0"
+      }
+    },
     "@babel/plugin-transform-unicode-regex": {
       "version": "7.7.0",
       "resolved": "https://registry.npmjs.org/@babel/plugin-transform-unicode-regex/-/plugin-transform-unicode-regex-7.7.0.tgz",
@@ -790,6 +824,16 @@
         "semver": "^5.5.0"
       }
     },
+    "@babel/preset-typescript": {
+      "version": "7.7.2",
+      "resolved": "https://registry.npmjs.org/@babel/preset-typescript/-/preset-typescript-7.7.2.tgz",
+      "integrity": "sha512-1B4HthAelaLGfNRyrWqJtBEjXX1ulThCrLQ5B2VOtEAznWFIFXFJahgXImqppy66lx/Oh+cOSCQdJzZqh2Jh5g==",
+      "dev": true,
+      "requires": {
+        "@babel/helper-plugin-utils": "^7.0.0",
+        "@babel/plugin-transform-typescript": "^7.7.2"
+      }
+    },
     "@babel/template": {
       "version": "7.7.0",
       "resolved": "https://registry.npmjs.org/@babel/template/-/template-7.7.0.tgz",
@@ -846,6 +890,91 @@
         "to-fast-properties": "^2.0.0"
       }
     },
+    "@types/eslint-visitor-keys": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/@types/eslint-visitor-keys/-/eslint-visitor-keys-1.0.0.tgz",
+      "integrity": "sha512-OCutwjDZ4aFS6PB1UZ988C4YgwlBHJd6wCeQqaLdmadZ/7e+w79+hbMUFC1QXDNCmdyoRfAFdm0RypzwR+Qpag==",
+      "dev": true
+    },
+    "@types/json-schema": {
+      "version": "7.0.3",
+      "resolved": "https://registry.npmjs.org/@types/json-schema/-/json-schema-7.0.3.tgz",
+      "integrity": "sha512-Il2DtDVRGDcqjDtE+rF8iqg1CArehSK84HZJCT7AMITlyXRBpuPhqGLDQMowraqqu1coEaimg4ZOqggt6L6L+A==",
+      "dev": true
+    },
+    "@typescript-eslint/eslint-plugin": {
+      "version": "2.7.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/eslint-plugin/-/eslint-plugin-2.7.0.tgz",
+      "integrity": "sha512-H5G7yi0b0FgmqaEUpzyBlVh0d9lq4cWG2ap0RKa6BkF3rpBb6IrAoubt1NWh9R2kRs/f0k6XwRDiDz3X/FqXhQ==",
+      "dev": true,
+      "requires": {
+        "@typescript-eslint/experimental-utils": "2.7.0",
+        "eslint-utils": "^1.4.2",
+        "functional-red-black-tree": "^1.0.1",
+        "regexpp": "^2.0.1",
+        "tsutils": "^3.17.1"
+      }
+    },
+    "@typescript-eslint/experimental-utils": {
+      "version": "2.7.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/experimental-utils/-/experimental-utils-2.7.0.tgz",
+      "integrity": "sha512-9/L/OJh2a5G2ltgBWJpHRfGnt61AgDeH6rsdg59BH0naQseSwR7abwHq3D5/op0KYD/zFT4LS5gGvWcMmegTEg==",
+      "dev": true,
+      "requires": {
+        "@types/json-schema": "^7.0.3",
+        "@typescript-eslint/typescript-estree": "2.7.0",
+        "eslint-scope": "^5.0.0"
+      }
+    },
+    "@typescript-eslint/parser": {
+      "version": "2.7.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/parser/-/parser-2.7.0.tgz",
+      "integrity": "sha512-ctC0g0ZvYclxMh/xI+tyqP0EC2fAo6KicN9Wm2EIao+8OppLfxji7KAGJosQHSGBj3TcqUrA96AjgXuKa5ob2g==",
+      "dev": true,
+      "requires": {
+        "@types/eslint-visitor-keys": "^1.0.0",
+        "@typescript-eslint/experimental-utils": "2.7.0",
+        "@typescript-eslint/typescript-estree": "2.7.0",
+        "eslint-visitor-keys": "^1.1.0"
+      }
+    },
+    "@typescript-eslint/typescript-estree": {
+      "version": "2.7.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/typescript-estree/-/typescript-estree-2.7.0.tgz",
+      "integrity": "sha512-vVCE/DY72N4RiJ/2f10PTyYekX2OLaltuSIBqeHYI44GQ940VCYioInIb8jKMrK9u855OEJdFC+HmWAZTnC+Ag==",
+      "dev": true,
+      "requires": {
+        "debug": "^4.1.1",
+        "glob": "^7.1.4",
+        "is-glob": "^4.0.1",
+        "lodash.unescape": "4.0.1",
+        "semver": "^6.3.0",
+        "tsutils": "^3.17.1"
+      },
+      "dependencies": {
+        "debug": {
+          "version": "4.1.1",
+          "resolved": "https://registry.npmjs.org/debug/-/debug-4.1.1.tgz",
+          "integrity": "sha512-pYAIzeRo8J6KPEaJ0VWOh5Pzkbw/RetuzehGM7QRRX5he4fPHx2rdKMB256ehJCkX+XRQm16eZLqLNS8RSZXZw==",
+          "dev": true,
+          "requires": {
+            "ms": "^2.1.1"
+          }
+        },
+        "ms": {
+          "version": "2.1.2",
+          "resolved": "https://registry.npmjs.org/ms/-/ms-2.1.2.tgz",
+          "integrity": "sha512-sGkPx+VjMtmA6MX27oA4FBFELFCZZ4S4XqeGOXCv68tT+jb3vk/RyaKWP0PTKyWtmLSM0b+adUTEvbs1PEaH2w==",
+          "dev": true
+        },
+        "semver": {
+          "version": "6.3.0",
+          "resolved": "https://registry.npmjs.org/semver/-/semver-6.3.0.tgz",
+          "integrity": "sha512-b39TBaTSfV6yBrapU89p5fKekE2m/NwnDocOVruQFS1/veMgdzuPcnOM34M6CwxW8jH/lxEa5rBoDeUwu5HHTw==",
+          "dev": true
+        }
+      }
+    },
     "acorn": {
       "version": "7.1.0",
       "resolved": "https://registry.npmjs.org/acorn/-/acorn-7.1.0.tgz",
@@ -2828,6 +2957,12 @@
       "integrity": "sha512-8xOcRHvCjnocdS5cpwXQXVzmmh5e5+saE2QGoeQmbKmRS6J3VQppPOIt0MnmE+4xlZoumy0GPG0D0MVIQbNA1A==",
       "dev": true
     },
+    "lodash.unescape": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/lodash.unescape/-/lodash.unescape-4.0.1.tgz",
+      "integrity": "sha1-vyJJiGzlFM2hEvrpIYzcBlIR/Jw=",
+      "dev": true
+    },
     "loose-envify": {
       "version": "1.4.0",
       "resolved": "https://registry.npmjs.org/loose-envify/-/loose-envify-1.4.0.tgz",
@@ -3879,6 +4014,15 @@
       "integrity": "sha512-qOebF53frne81cf0S9B41ByenJ3/IuH8yJKngAX35CmiZySA0khhkovshKK+jGCaMnVomla7gVlIcc3EvKPbTQ==",
       "dev": true
     },
+    "tsutils": {
+      "version": "3.17.1",
+      "resolved": "https://registry.npmjs.org/tsutils/-/tsutils-3.17.1.tgz",
+      "integrity": "sha512-kzeQ5B8H3w60nFY2g8cJIuH7JDpsALXySGtwGJ0p2LSjLgay3NdIpqq5SoOBe46bKDW2iq25irHCr8wjomUS2g==",
+      "dev": true,
+      "requires": {
+        "tslib": "^1.8.1"
+      }
+    },
     "type-check": {
       "version": "0.3.2",
       "resolved": "https://registry.npmjs.org/type-check/-/type-check-0.3.2.tgz",
@@ -3894,6 +4038,12 @@
       "integrity": "sha512-DWkS49EQKVX//Tbupb9TFa19c7+MK1XmzkrZUR8TAktmE/DizXoaoJV6TZ/tSIPXipqNiRI6CyAe7x69Jb6RSw==",
       "dev": true
     },
+    "typescript": {
+      "version": "3.7.2",
+      "resolved": "https://registry.npmjs.org/typescript/-/typescript-3.7.2.tgz",
+      "integrity": "sha512-ml7V7JfiN2Xwvcer+XAf2csGO1bPBdRbFCkYBczNZggrBZ9c7G3riSUeJmqEU5uOtXNPMhE3n+R4FA/3YOAWOQ==",
+      "dev": true
+    },
     "unicode-canonical-property-names-ecmascript": {
       "version": "1.0.4",
       "resolved": "https://registry.npmjs.org/unicode-canonical-property-names-ecmascript/-/unicode-canonical-property-names-ecmascript-1.0.4.tgz",

package.json

@@ -4,19 +4,24 @@
   "author": "Kent C. Dodds (http://kentcdodds.com/)",
   "license": "GPLv3",
   "scripts": {
-    "build": "babel src --out-dir dist",
+    "build": "babel src --extensions .js,.ts,.tsx --out-dir dist",
-    "lint": "eslint --ignore-path .gitignore .",
+    "lint": "eslint --ignore-path .gitignore --ext .js,.ts,.tsx .",
-    "prettier": "prettier --ignore-path .gitignore \"**/*.+(js|json)\"",
+    "check-types": "tsc",
+    "prettier": "prettier --ignore-path .gitignore \"**/*.+(js|json|ts|tsx)\"",
     "format": "npm run prettier -- --write",
     "check-format": "npm run prettier -- --list-different",
-    "validate": "npm run check-format && npm run lint && npm run build"
+    "validate": "npm run check-types && npm run check-format && npm run lint && npm run build"
   },
   "devDependencies": {
     "@babel/cli": "^7.7.0",
     "@babel/core": "^7.7.2",
     "@babel/preset-env": "^7.7.1",
+    "@babel/preset-typescript": "^7.7.2",
+    "@typescript-eslint/eslint-plugin": "^2.7.0",
+    "@typescript-eslint/parser": "^2.7.0",
     "eslint": "^6.6.0",
     "eslint-config-prettier": "^6.5.0",
-    "prettier": "^1.19.1"
+    "prettier": "^1.19.1",
+    "typescript": "^3.7.2"
   }
 }

src/typescript-example.js

@@ -1,14 +0,0 @@
-function add(a, b) {
-  return a + b
-}
-
-function getFullName(user) {
-  const {
-    name: {first, middle, last},
-  } = user
-  return [first, middle, last].filter(Boolean).join('')
-}
-
-add(1, 'two')
-
-getFullName({name: {first: 'Joe', midd1e: 'Bud', last: 'Matthews'}})

src/typescript-example.ts

@@ -0,0 +1,21 @@
+function add(a: number, b: number): number {
+  return a + b
+}
+
+interface User {
+  name: {
+    first: string
+    middle: string
+    last: string
+  }
+}
+function getFullName(user: User): string {
+  const {
+    name: {first, middle, last},
+  } = user
+  return [first, middle, last].filter(Boolean).join('')
+}
+
+add(1, 2)
+
+getFullName({name: {first: 'Joe', middle: 'Bud', last: 'Matthews'}})

tsconfig.json

@@ -0,0 +1,6 @@
+{
+  "compilerOptions": {
+    "noEmit": true,
+    "baseUrl": "./src"
+  }
+}