Separate languages functionality doesn't work correctly for composite…

packages/survey-core/src/base.ts

@@ -451,6 +451,11 @@ export class Base implements IObjectValueContext {
   protected mergeLocalizationObj(obj: Base, locales?: Array<string>): void {
     this.mergeLocalizationInObjectCore(obj, locales);
     this.mergeLocalizationInArrays(obj, locales);
+    const orgObj = obj.getOriginalObj();
+    const org = this.getOriginalObj();
+    if (orgObj !== obj && org !== this) {
+      org.mergeLocalizationObj(orgObj, locales);
+    }
   }
   private mergeLocalizationInObjectCore(obj: Base, locales?: Array<string>): void {
     if (!this.canMergeObj(obj)) return;
@@ -471,7 +476,6 @@ export class Base implements IObjectValueContext {
     if (!obj || typeof obj.mergeLocalizationObj !== "function") return false;
     const self: any = this;
     if (obj["name"] && self.name !== obj["name"]) return false;
-    if (obj["value"] && self.value !== obj["value"]) return false;
     return true;
   }
   private mergeLocalizationInArrays(obj: Base, locales?: Array<string>): void {

packages/survey-core/src/question_custom.ts

@@ -804,6 +804,12 @@ export class QuestionCustomModel extends QuestionCustomModelBase {
   public getOriginalObj(): Base {
     return this.questionWrapper;
   }
+  public getOriginalByProperty(propName: string): Base {
+    const inProps = this.customQuestion?.json?.inheritBaseProps;
+    let isInheritedProp = inProps === true || (Array.isArray(inProps) && inProps.indexOf(propName) > -1);
+    if (!isInheritedProp && !!Serializer.findProperty("question", propName)) return this;
+    return super.getOriginalByProperty(propName);
+  }
   protected createWrapper(): void {
     this.questionWrapper = this.createQuestion();
     this.createDynamicProperties(this.questionWrapper);

packages/survey-core/tests/question_customtests.ts

@@ -4253,3 +4253,125 @@ QUnit.test("Composite: allow to make the custom number rendering", function (ass
 
   ComponentCollection.Instance.clear();
 });
+QUnit.test("Single: Merge with separate locale strings, Bug#10771", (assert) => {
+  ComponentCollection.Instance.add({
+    name: "newquestion",
+    inheritBaseProps: ["choices"],
+    questionJSON:
+      {
+        type: "dropdown",
+      }
+  });
+  var survey = new SurveyModel({
+    elements: [{
+      type: "newquestion",
+      name: "q1",
+      title: { default: "Title", de: "Titel" },
+      description: { default: "Description", de: "Beschreibung" },
+      choices: [{ value: 1, text: { default: "item en", de: "item de" } }]
+    }]
+  });
+  const plainJSON = survey.toJSON({ storeLocaleStrings: false });
+  assert.deepEqual(plainJSON.pages[0].elements[0], {
+    type: "newquestion",
+    name: "q1",
+    choices: [1]
+  }, "check plain json");
+  const enJSON = survey.getLocalizationJSON(["default"]);
+  assert.deepEqual(enJSON.pages[0].elements[0], {
+    type: "newquestion",
+    name: "q1",
+    title: "Title",
+    description: "Description",
+    choices: [{ value: 1, text: "item en" }]
+  }, "check en json");
+  const deJSON = survey.getLocalizationJSON(["de"]);
+  assert.deepEqual(deJSON.pages[0].elements[0], {
+    type: "newquestion",
+    name: "q1",
+    title: "Titel",
+    description: "Beschreibung",
+    choices: [{ value: 1, text: "item de" }]
+  }, "check de json");
+  const mergedSurvey = new SurveyModel(plainJSON);
+  mergedSurvey.mergeLocalizationJSON(enJSON);
+  mergedSurvey.mergeLocalizationJSON(deJSON);
+  assert.deepEqual(mergedSurvey.toJSON().pages[0].elements[0], {
+    type: "newquestion",
+    name: "q1",
+    title: { default: "Title", de: "Titel" },
+    description: { default: "Description", de: "Beschreibung" },
+    choices: [{ value: 1, text: { default: "item en", de: "item de" } }]
+  }, "check merged json");
+  ComponentCollection.Instance.clear();
+});
+QUnit.test("Composite: Merge with separate locale strings, Bug#10771", (assert) => {
+  ComponentCollection.Instance.add(<any>{
+    name: "newquestion",
+    elementsJSON:
+      [{
+        type: "dropdown",
+        name: "myQuestion",
+      }],
+    onInit() {
+      Serializer.addProperty("newquestion", {
+        name: "myChoices:choiceitem[]",
+      });
+    },
+    onLoaded(question: QuestionCompositeModel) {
+      this.setChoices(question);
+    },
+    onPropertyChanged(question: QuestionCompositeModel, propertyName: string) {
+      if (propertyName == "myChoices") {
+        this.setChoices(question);
+      }
+    },
+    setChoices: (question: QuestionCompositeModel) => {
+      const choices = question.myChoices;
+      const dropdown = question.contentPanel.getQuestionByName("myQuestion") as QuestionDropdownModel;
+      dropdown.choices = choices;
+    }
+  });
+  var survey = new SurveyModel({
+    elements: [{
+      type: "newquestion",
+      name: "q1",
+      title: { default: "Title", de: "Titel" },
+      description: { default: "Description", de: "Beschreibung" },
+      myChoices: [{ value: 1, text: { default: "item en", de: "item de" } }]
+    }]
+  });
+  const plainJSON = survey.toJSON({ storeLocaleStrings: false });
+  assert.deepEqual(plainJSON.pages[0].elements[0], {
+    type: "newquestion",
+    name: "q1",
+    myChoices: [1]
+  }, "check plain json");
+  const enJSON = survey.getLocalizationJSON(["default"]);
+  assert.deepEqual(enJSON.pages[0].elements[0], {
+    type: "newquestion",
+    name: "q1",
+    title: "Title",
+    description: "Description",
+    myChoices: [{ value: 1, text: "item en" }]
+  }, "check en json");
+  const deJSON = survey.getLocalizationJSON(["de"]);
+  assert.deepEqual(deJSON.pages[0].elements[0], {
+    type: "newquestion",
+    name: "q1",
+    title: "Titel",
+    description: "Beschreibung",
+    myChoices: [{ value: 1, text: "item de" }]
+  }, "check de json");
+  const mergedSurvey = new SurveyModel(plainJSON);
+  mergedSurvey.mergeLocalizationJSON(enJSON);
+  mergedSurvey.mergeLocalizationJSON(deJSON);
+  assert.deepEqual(mergedSurvey.toJSON().pages[0].elements[0], {
+    type: "newquestion",
+    name: "q1",
+    title: { default: "Title", de: "Titel" },
+    description: { default: "Description", de: "Beschreibung" },
+    myChoices: [{ value: 1, text: { default: "item en", de: "item de" } }]
+  }, "check merged json");
+  ComponentCollection.Instance.clear();
+});