refactor: replace Joi with Zod and make use of type inference

package.json

@@ -91,8 +91,8 @@
   "dependencies": {
     "@sindresorhus/is": "4.6.0",
     "chalk": "4.1.2",
-    "joi": "17.4.2",
     "json-stringify-pretty-compact": "3.0.0",
-    "moment": "2.29.1"
+    "moment": "2.29.1",
+    "zod": "3.11.6"
   }
 }

src/bunyan-pretty-stream.ts

@@ -1,22 +1,16 @@
-import { MergedOptions, Options, schema } from './options';
+import { Options, schema } from './options';
 import { Transform, TransformCallback } from 'stream';
 import { fromString, isBunyanRecord } from './bunyan-record';
 import { Formatter } from './formatter';
 import is from '@sindresorhus/is';
-import { joi } from './helpers';
 
 class PrettyStream extends Transform {
   private _formatter: Formatter;
 
   constructor(options: Options = {}) {
     super({ objectMode: true });
 
-    const validation = schema.validate(options);
-    if (!joi.isValid<MergedOptions>(validation, validation.value)) {
-      throw validation.error;
-    }
-
-    this._formatter = new Formatter(validation.value);
+    this._formatter = new Formatter(schema.parse(options));
   }
 
   _transform(

src/formatter.ts

@@ -79,17 +79,18 @@ class Formatter {
       return parsed;
     }
 
-    const extras = parsed.details[this._options.extrasKey];
-    if (this._options.extrasKey !== '' && is.nonEmptyObject(extras)) {
-      Object.entries(parsed.details[this._options.extrasKey]).forEach(
-        ([key, value]) => {
-          if (this.isExtra(value)) {
-            parsed.extras[key] = value;
-            delete parsed.details[this._options.extrasKey][key];
-          }
-        },
-      );
-    } else if (this._options.extrasKey === '') {
+    const extras = is.undefined(this._options.extrasKey)
+      ? {}
+      : parsed.details[this._options.extrasKey];
+    if (this._options.extrasKey !== undefined && is.nonEmptyObject(extras)) {
+      const extrasKey = this._options.extrasKey;
+      Object.entries(parsed.details[extrasKey]).forEach(([key, value]) => {
+        if (this.isExtra(value)) {
+          parsed.extras[key] = value;
+          delete parsed.details[extrasKey][key];
+        }
+      });
+    } else if (this._options.extrasKey === undefined) {
       Object.entries(parsed.details).forEach(([key, value]) => {
         if (this.isExtra(value)) {
           parsed.extras[key] = value;