Add tsconfig

packages/utils/tsconfig.json

@@ -0,0 +1,78 @@
+{
+    /* Docs: https://aka.ms/tsconfig.json */
+    "compilerOptions": {
+        /* We use TypeScript as a type checker, not as a build tool */
+        "noEmit": true,
+
+        /*
+         * Tell TypeScript which all things it can assume that our target
+         * runtime will have.
+         *
+         * In our case, we tell it that the code will run in a modern browser,
+         * and will have access to a latest JS (esnext) and the DOM (dom). Our
+         * transpiler (Babel via Next.js) will take care that these things hold.
+         *
+         * Unlike the other individual library components (say how "esnext"
+         * implies "esnext.*"), "dom.iterable" (the ability to iterate over DOM
+         * elements) is not a subset of "dom" and needs to be listed out
+         * explicitly.
+         *
+         * Note that we don't need to specify target, since TypeScript isn't
+         * actually generating (emitting) the JavaScript.
+         */
+        "lib": ["esnext", "dom", "dom.iterable"],
+
+        /*
+         * The module system to assume the generated JavaScript will use.
+         *
+         * Since we're using a bundler, we should set this to esnext
+         * https://www.typescriptlang.org/docs/handbook/modules/guides/choosing-compiler-options.html
+         */
+        "module": "esnext",
+        /*
+         * Tell TypeScript how to lookup the file for a given import
+         *
+         * From the TypeScript docs:
+         *
+         * > 'bundler' is for use with bundlers. Like node16 and nodenext, this
+         *   mode supports package.json `imports` and `exports`, but unlinke the
+         *   Node.js resolution modes, bundler never requires file extensions on
+         *   relative paths in imports.
+         *
+         * > bundler does not support resolution of `require` calls.
+         */
+        "moduleResolution": "bundler",
+
+        /* Allow use of `.tsx` files */
+        "jsx": "preserve",
+
+        /* Ask TypeScript to warn us if we use TypeScript features that cannot
+           be used by single-file transpilers (Babel in our case) */
+        "isolatedModules": true,
+        /* Enable various workarounds to play better with CJS libraries */
+        "esModuleInterop": true,
+
+        /* Speed things up by not type checking `node_modules` */
+        "skipLibCheck": true,
+        /* Ensure filename in import has the same casing as the file on disk */
+        "forceConsistentCasingInFileNames": true,
+        /* Require the `type` modifier when importing types */
+        "verbatimModuleSyntax": true,
+        /* Enable importing .json files */
+        "resolveJsonModule": true,
+
+        "strict": true,
+        /* Stricter than strict */
+        "noImplicitReturns": true,
+        "noUnusedParameters": true,
+        "noUnusedLocals": true,
+        "noFallthroughCasesInSwitch": true,
+        /* e.g. makes array indexing returns undefined */
+        "noUncheckedIndexedAccess": true,
+        "exactOptionalPropertyTypes": true
+    },
+    /*
+     * Typecheck all files (here or in subfolders) with the given extensions
+     */
+    "include": ["**/*.ts", "**/*.tsx"]
+}