From e482fdcafc8bc8219e6f44fee18d0ff52a1fe07e Mon Sep 17 00:00:00 2001
From: Andrew Telnov <andrew.telnov@gmail.com>
Date: Fri, 30 Jul 2021 15:32:49 +0300
Subject: [PATCH] Fix: Do not call notification on setting the same value in
 select base renderedValue property #3160

---
 src/question_baseselect.ts           |  5 +++-
 tests/question_matrixdynamictests.ts | 39 ++++++++++++++++++++++++++++
 2 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/src/question_baseselect.ts b/src/question_baseselect.ts
index 1a69b61176..7cb4bb71a3 100644
--- a/src/question_baseselect.ts
+++ b/src/question_baseselect.ts
@@ -342,7 +342,10 @@ export class QuestionSelectBase extends Question {
   }
   public set renderedValue(val: any) {
     this.setPropertyValue("renderedValue", val);
-    this.value = this.rendredValueToData(val);
+    var val = this.rendredValueToData(val);
+    if (!Helpers.isTwoValueEquals(val, this.value)) {
+      this.value = val;
+    }
   }
   protected setQuestionValue(
     newValue: any,
diff --git a/tests/question_matrixdynamictests.ts b/tests/question_matrixdynamictests.ts
index 5d605d90f5..5e2eda41c0 100644
--- a/tests/question_matrixdynamictests.ts
+++ b/tests/question_matrixdynamictests.ts
@@ -6765,3 +6765,42 @@ QUnit.test(
     assert.equal(counter, 1, "value is correct");
   }
 );
+QUnit.test(
+  "Matrixdynamic onMatrixValueChanging - do not call event on set the same renderedValue",
+  function(assert) {
+    var json = {
+      questions: [
+        {
+          type: "matrixdynamic",
+          name: "q1",
+          rowCount: 1,
+          columns: [
+            {
+              name: "col1",
+              choices: [1, 2, 3, 4, 5],
+            },
+          ],
+        },
+      ],
+    };
+    var survey = new SurveyModel(json);
+    var counter = 0;
+    survey.onMatrixCellValueChanging.add(function(sender, options) {
+      counter++;
+    });
+    var matrix = <QuestionMatrixDynamicModel>survey.getQuestionByName("q1");
+    var cellQuestion = <QuestionDropdownModel>(
+      matrix.visibleRows[0].cells[0].question
+    );
+    cellQuestion.renderedValue = undefined;
+    assert.equal(counter, 0, "There is not value to clear");
+    cellQuestion.renderedValue = 1;
+    assert.equal(counter, 1, "Call one time");
+    cellQuestion.renderedValue = 1;
+    assert.equal(counter, 1, "Do not call on the same value");
+    cellQuestion.renderedValue = undefined;
+    assert.equal(counter, 2, "Value is undefined");
+    cellQuestion.renderedValue = undefined;
+    assert.equal(counter, 2, "Value is still undefined");
+  }
+);