From 85a2fc06c168a2870374c6b8f29699262ace607d Mon Sep 17 00:00:00 2001
From: Tomi Virkki <virkki@vaadin.com>
Date: Mon, 15 Oct 2018 14:30:58 +0300
Subject: [PATCH] Don't throw with large size

---
 src/vaadin-combo-box-data-provider-mixin.html | 12 ++++++------
 test/lazy-loading.html                        |  4 ++++
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/src/vaadin-combo-box-data-provider-mixin.html b/src/vaadin-combo-box-data-provider-mixin.html
index 8ee8abfe9..f3186e7a2 100644
--- a/src/vaadin-combo-box-data-provider-mixin.html
+++ b/src/vaadin-combo-box-data-provider-mixin.html
@@ -175,12 +175,12 @@
       }
     }
 
-    _sizeChanged(size) {
-      const filteredItems = this.filteredItems || [];
-      filteredItems.length = size || 0;
-      this.filteredItems = new Array(...filteredItems).map(item => {
-        return item !== undefined ? item : new Vaadin.ComboBoxPlaceholder();
-      });
+    _sizeChanged(size = 0) {
+      const filteredItems = (this.filteredItems || []).slice(0);
+      for (let i = 0; i < size; i++) {
+        filteredItems[i] = filteredItems[i] !== undefined ? filteredItems[i] : new Vaadin.ComboBoxPlaceholder();
+      }
+      this.filteredItems = filteredItems;
     }
 
     _pageSizeChanged(pageSize, oldPageSize) {
diff --git a/test/lazy-loading.html b/test/lazy-loading.html
index 7506bdf5c..b144fde8f 100644
--- a/test/lazy-loading.html
+++ b/test/lazy-loading.html
@@ -88,6 +88,10 @@
             expect(spyDataProvider).to.be.calledOnce;
           });
 
+          it('should not throw with large size', () => {
+            expect(() => comboBox.size = 500000).not.to.throw(Error);
+          });
+
           it('should throw if set after items', () => {
             comboBox.items = ['foo'];
             function setDataProvider() {