Duplicate Error Messages During Async Validation fix #8993 (#9191)

packages/survey-core/src/validator.ts

@@ -481,23 +481,22 @@ export class ExpressionValidator extends SurveyValidator {
   public getType(): string {
     return "expressionvalidator";
   }
-  public get isValidateAllValues() {
+  public get isValidateAllValues(): boolean {
     return true;
   }
   public get isAsync(): boolean {
-    if (!this.ensureConditionRunner()) return false;
+    if (!this.ensureConditionRunner(false)) return false;
     return this.conditionRunner.isAsync;
   }
   public get isRunning(): boolean {
     return this.isRunningValue;
   }
-  public validate(
-    value: any,
-    name: string = null,
-    values: any = null,
-    properties: any = null
-  ): ValidatorResult {
-    if (!this.ensureConditionRunner()) return null;
+  public validate(value: any, name: string = null, values: any = null, properties: any = null): ValidatorResult {
+    if (!this.expression) return null;
+    if(!!this.conditionRunner) {
+      this.conditionRunner.onRunComplete = null;
+    }
+    this.ensureConditionRunner(true);
     this.conditionRunner.onRunComplete = (res) => {
       this.isRunningValue = false;
       if (!!this.onAsyncCompleted) {
@@ -510,22 +509,22 @@ export class ExpressionValidator extends SurveyValidator {
     this.isRunningValue = false;
     return this.generateError(res, value, name);
   }
-  protected generateError(res: boolean, value: any, name: string) {
+  protected generateError(res: boolean, value: any, name: string): ValidatorResult {
     if (!res) {
       return new ValidatorResult(value, this.createCustomError(name));
     }
     return null;
   }
-  protected getDefaultErrorText(name: string) {
+  protected getDefaultErrorText(name: string): string {
     return this.getLocalizationFormatString("invalidExpression", this.expression);
   }
-  protected ensureConditionRunner(): boolean {
-    if (!!this.conditionRunner) {
+  private ensureConditionRunner(reNew: boolean): boolean {
+    if (!this.expression) return false;
+    if(reNew || !this.conditionRunner) {
+      this.conditionRunner = new ConditionRunner(this.expression);
+    } else {
       this.conditionRunner.expression = this.expression;
-      return true;
     }
-    if (!this.expression) return false;
-    this.conditionRunner = new ConditionRunner(this.expression);
     return true;
   }
   /**

packages/survey-core/tests/surveyvalidatortests.ts

@@ -554,3 +554,49 @@ QUnit.test("settings.readOnly.enableValidation option", function(assert) {
   assert.equal(q1.errors.length, 1, "There is an error");
   settings.readOnly.enableValidation = false;
 });
+QUnit.test("Async expression validators creates several errors", function(assert) {
+  const asynList = new Array<any>();
+  function asyncFunc(params) {
+    asynList.push(this.returnResult);
+  }
+  FunctionFactory.Instance.register("asyncFunc", asyncFunc, true);
+  function callAsyncList(): void {
+    while(asynList.length > 0) {
+      let i = asynList.length % 2;
+      if(i >= asynList.length) i = 0;
+      asynList[i](false);
+      asynList.splice(i, 1);
+    }
+  }
+  const survey = new SurveyModel({
+    elements: [
+      {
+        type: "text",
+        name: "q1",
+        validators: [{ type: "expression", expression: "asyncFunc({question1})" }]
+      },
+      {
+        type: "text",
+        name: "q2",
+        validators: [{ type: "expression", expression: "asyncFunc({question1})" }]
+      }
+    ]
+  });
+  const q1 = survey.getQuestionByName("q1");
+  const q2 = survey.getQuestionByName("q2");
+  q1.value = "a";
+  q1.valule = "b";
+  survey.validate(true);
+  assert.equal(asynList.length, 2, "#1.0");
+  callAsyncList();
+  assert.equal(q1.errors.length, 1, "#1.1");
+  assert.equal(q2.errors.length, 1, "#1.2");
+  q1.value = "aa";
+  callAsyncList();
+  assert.equal(q1.errors.length, 1, "#2.1");
+  assert.equal(q2.errors.length, 1, "#2.2");
+  q2.value = "bb";
+  callAsyncList();
+  assert.equal(q1.errors.length, 1, "#3.1");
+  assert.equal(q2.errors.length, 1, "#3.2");
+});