From 2cc9e311a38b8074fd1b30c073f3a7a506c8c75f Mon Sep 17 00:00:00 2001
From: Simon Boudrias <admin@simonboudrias.com>
Date: Wed, 17 Jul 2024 17:17:32 -0400
Subject: [PATCH] Fix(inquirer): Ensure no mutation of the question objects

---
 packages/inquirer/src/types.mts     | 60 +++++++++++++++--------------
 packages/inquirer/src/ui/prompt.mts | 20 ++++++++--
 2 files changed, 48 insertions(+), 32 deletions(-)

diff --git a/packages/inquirer/src/types.mts b/packages/inquirer/src/types.mts
index 54fb8a890..e0d0f6b56 100644
--- a/packages/inquirer/src/types.mts
+++ b/packages/inquirer/src/types.mts
@@ -41,43 +41,45 @@ export interface QuestionMap {
 }
 
 type PromptConfigMap<A extends Answers> = {
-  [key in keyof QuestionMap]: DistributiveMerge<
-    QuestionMap[keyof QuestionMap],
-    {
-      type: keyof QuestionMap;
-      name: KeyUnion<A>;
-      when?: AsyncGetterFunction<boolean, Prettify<A>> | boolean;
-      askAnswered?: boolean;
-      message:
-        | Pick<QuestionMap[keyof QuestionMap], 'message'>
-        | AsyncGetterFunction<
-            Pick<QuestionMap[keyof QuestionMap], 'message'>,
-            Prettify<A>
-          >;
-      choices?:
-        | Pick<QuestionMap[keyof QuestionMap], 'choices'>
-        | string[]
-        | AsyncGetterFunction<
-            Pick<QuestionMap[keyof QuestionMap], 'choices'> | string[],
-            Prettify<A>
-          >;
-      default?:
-        | Pick<QuestionMap[keyof QuestionMap], 'default'>
-        | AsyncGetterFunction<
-            Pick<QuestionMap[keyof QuestionMap], 'default'> | string[],
-            Prettify<A>
-          >;
-    }
+  [key in keyof QuestionMap]: Readonly<
+    DistributiveMerge<
+      QuestionMap[keyof QuestionMap],
+      {
+        type: keyof QuestionMap;
+        name: KeyUnion<A>;
+        when?: AsyncGetterFunction<boolean, Prettify<A>> | boolean;
+        askAnswered?: boolean;
+        message:
+          | Pick<QuestionMap[keyof QuestionMap], 'message'>
+          | AsyncGetterFunction<
+              Pick<QuestionMap[keyof QuestionMap], 'message'>,
+              Prettify<A>
+            >;
+        choices?:
+          | Pick<QuestionMap[keyof QuestionMap], 'choices'>
+          | string[]
+          | AsyncGetterFunction<
+              Pick<QuestionMap[keyof QuestionMap], 'choices'> | string[],
+              Prettify<A>
+            >;
+        default?:
+          | Pick<QuestionMap[keyof QuestionMap], 'default'>
+          | AsyncGetterFunction<
+              Pick<QuestionMap[keyof QuestionMap], 'default'> | string[],
+              Prettify<A>
+            >;
+      }
+    >
   >;
 };
 
 export type Question<A extends Answers> = PromptConfigMap<A>[keyof PromptConfigMap<A>];
 
 export type QuestionAnswerMap<A extends Answers> =
-  | { [name in KeyUnion<A>]: Omit<Question<A>, 'name'> }
+  | Readonly<{ [name in KeyUnion<A>]: Omit<Question<A>, 'name'> }>
   | never;
 
-export type QuestionArray<A extends Answers> = Question<A>[] | never;
+export type QuestionArray<A extends Answers> = readonly Question<A>[] | never;
 
 export type QuestionObservable<A extends Answers> = Observable<Question<A>> | never;
 
diff --git a/packages/inquirer/src/ui/prompt.mts b/packages/inquirer/src/ui/prompt.mts
index 12ccb2d89..20f2ef772 100644
--- a/packages/inquirer/src/ui/prompt.mts
+++ b/packages/inquirer/src/ui/prompt.mts
@@ -158,8 +158,22 @@ function setupReadlineOptions(opt: StreamOptions = {}) {
   };
 }
 
+function isQuestionArray<A extends Answers>(
+  questions:
+    | QuestionArray<A>
+    | QuestionAnswerMap<A>
+    | QuestionObservable<A>
+    | Question<A>,
+): questions is QuestionArray<A> {
+  return Array.isArray(questions);
+}
+
 function isQuestionMap<A extends Answers>(
-  questions: QuestionArray<A> | QuestionAnswerMap<A> | Question<A>,
+  questions:
+    | QuestionArray<A>
+    | QuestionAnswerMap<A>
+    | QuestionObservable<A>
+    | Question<A>,
 ): questions is QuestionAnswerMap<A> {
   return Object.values(questions).every(
     (maybeQuestion) =>
@@ -207,7 +221,7 @@ export default class PromptsRunner<A extends Answers> {
     this.answers = typeof answers === 'object' ? { ...answers } : {};
 
     let obs: Observable<Question<A>>;
-    if (Array.isArray(questions)) {
+    if (isQuestionArray(questions)) {
       obs = from(questions);
     } else if (isObservable(questions)) {
       obs = questions;
@@ -366,7 +380,7 @@ export default class PromptsRunner<A extends Answers> {
   setDefaultType = (question: Question<A>): Observable<Question<A>> => {
     // Default type to input
     if (!this.prompts[question.type]) {
-      question.type = 'input';
+      question = Object.assign({}, question, { type: 'input' });
     }
 
     return defer(() => of(question));