diff --git a/tests/src/core/geometry/testqgsgeometry.cpp b/tests/src/core/geometry/testqgsgeometry.cpp
index 63d50c140dd..6fe37f090e1 100644
--- a/tests/src/core/geometry/testqgsgeometry.cpp
+++ b/tests/src/core/geometry/testqgsgeometry.cpp
@@ -2597,13 +2597,17 @@ void TestQgsGeometry::snappedToGrid()
     QCOMPARE( snapped->asWkt( 5 ), QStringLiteral( "LineStringZM (68 415 10 60, 27 505 20 50, 27 406 40 30)" ) );
 
     // with removal of redundant vertices
-    curve = QgsGeometry::fromWkt( "LineString( 68.1 415.2, 27.1 505.2, 27.1 406.2 )" );
-    curve.densifyByCount( 10 );
+    curve = QgsGeometry::fromWkt( "LineString( 68.1 415.2, 68.1 505.2, 27.1 505.2 )" );
+    curve = curve.densifyByCount( 10 );
+    // no removal of redundant vertices
+    snapped.reset( curve.constGet()->snappedToGrid( 1, 1, 0, 0, false ) );
+    QCOMPARE( snapped->nCoordinates(), 23 );
+    // removal of redundant vertices
     snapped.reset( curve.constGet()->snappedToGrid( 1, 1, 0, 0, true ) );
-    QCOMPARE( snapped->asWkt( 5 ), QStringLiteral( "LineString (68 415, 27 505, 27 406)" ) );
-    curve.densifyByCount( 1000 );
+    QCOMPARE( snapped->asWkt( 5 ), QStringLiteral( "LineString (68 415, 68 505, 27 505)" ) );
+    curve = curve.densifyByCount( 1000 );
     snapped.reset( curve.constGet()->snappedToGrid( 1, 1, 0, 0, true ) );
-    QCOMPARE( snapped->asWkt( 5 ), QStringLiteral( "LineString (68 415, 27 505, 27 406)" ) );
+    QCOMPARE( snapped->asWkt( 5 ), QStringLiteral( "LineString (68 415, 68 505, 27 505)" ) );
   }
 
   //compound curve