✨ add default TypeScript ESLint config if TypeScript is installed

Author: blakek

config/eslint/.eslintrc.js

@@ -1,10 +1,28 @@
+const { has } = require('@blakek/deep');
 const { projectPackageJson } = require('../../src/utils');
 
-const isReactInstalled =
-  projectPackageJson &&
-  projectPackageJson.dependencies &&
-  projectPackageJson.dependencies.react;
+function isDependentOn(dependencyName) {
+  return (
+    has(['dependencies', dependencyName], projectPackageJson) ||
+    has(['devDependencies', dependencyName], projectPackageJson)
+  );
+}
+
+function getBaseConfig() {
+  if (isDependentOn('typescript')) {
+    return 'gsandf-typescript';
+  }
+
+  if (isDependentOn('react')) {
+    return 'gsandf-react';
+  }
+
+  return 'gsandf';
+}
 
 module.exports = {
-  extends: [isReactInstalled ? 'gsandf-react' : 'gsandf']
+  extends: [getBaseConfig()],
+  parserOptions: {
+    project: './tsconfig.json'
+  }
 };

package.json

@@ -24,14 +24,16 @@
   },
   "version": "1.1.0",
   "dependencies": {
+    "@blakek/deep": "^2.2.0",
     "babel-eslint": "^10.1.0",
     "common-tags": "^1.8.0",
-    "eslint": "^7.17.0",
-    "eslint-config-gsandf": "^2.0.0",
-    "eslint-config-gsandf-react": "^2.0.1",
-    "execa": "^5.0.0",
+    "eslint": "^7.29.0",
+    "eslint-config-gsandf": "^3.0.0",
+    "eslint-config-gsandf-react": "^3.0.0",
+    "eslint-config-gsandf-typescript": "^1.0.2",
+    "execa": "^5.1.1",
     "listr": "^0.14.3",
-    "prettier": "^2.2.1",
+    "prettier": "^2.3.2",
     "read-pkg-up": "^7.0.1"
   }
 }