fix: restrict single select questions to one correct answer (#2618)

Author: djoseph-apphelix

src/editors/containers/ProblemEditor/components/EditProblemView/AnswerWidget/hooks.js

@@ -90,7 +90,7 @@ export const useFeedback = (answer) => {
 };
 
 export const isSingleAnswerProblem = (problemType) => (
-  problemType === ProblemTypeKeys.DROPDOWN
+  problemType === ProblemTypeKeys.SINGLESELECT || problemType === ProblemTypeKeys.DROPDOWN
 );
 
 export const useAnswerContainer = ({ answers, updateField }) => {

src/editors/containers/ProblemEditor/components/EditProblemView/AnswerWidget/hooks.test.js

@@ -200,7 +200,7 @@ describe('Answer Options Hooks', () => {
   });
   describe('isSingleAnswerProblem()', () => {
     test('singleSelect', () => {
-      expect(module.isSingleAnswerProblem(ProblemTypeKeys.SINGLESELECT)).toBe(false);
+      expect(module.isSingleAnswerProblem(ProblemTypeKeys.SINGLESELECT)).toBe(true);
     });
     test('multiSelect', () => {
       expect(module.isSingleAnswerProblem(ProblemTypeKeys.MULTISELECT)).toBe(false);

src/editors/containers/ProblemEditor/components/EditProblemView/SettingsWidget/hooks.js

@@ -299,9 +299,9 @@ export const typeRowHooks = ({
     if (typeKey === ProblemTypeKeys.TEXTINPUT && RichTextProblems.includes(problemType)) {
       convertToPlainText();
     }
-    // Dropdown problems can only have one correct answer. When there is more than one correct answer
+    // Dropdown and single-select problems can only have one correct answer. When there is more than one correct answer
     // from a previous problem type, the correct attribute for selected answers need to be set to false.
-    if (typeKey === ProblemTypeKeys.DROPDOWN) {
+    if (typeKey === ProblemTypeKeys.DROPDOWN || typeKey === ProblemTypeKeys.SINGLESELECT) {
       if (correctAnswerCount > 1) {
         clearPreviouslySelectedAnswers();
       } else if (RichTextProblems.includes(problemType)) {