From b35cfe7e98f792eb07ca74b9e34da8e052887661 Mon Sep 17 00:00:00 2001
From: "Maxim.Mossienko" <Maxim.Mossienko@jetbrains.com>
Date: Mon, 31 Oct 2016 18:00:49 +0100
Subject: [PATCH] IDEA freezes for half a minute on window activation
 (IDEA-162538)

---
 .../src/com/intellij/util/indexing/FileBasedIndexImpl.java       | 1 +
 1 file changed, 1 insertion(+)

diff --git a/platform/lang-impl/src/com/intellij/util/indexing/FileBasedIndexImpl.java b/platform/lang-impl/src/com/intellij/util/indexing/FileBasedIndexImpl.java
index 257a72fae253..34c01d0ca5d3 100644
--- a/platform/lang-impl/src/com/intellij/util/indexing/FileBasedIndexImpl.java
+++ b/platform/lang-impl/src/com/intellij/util/indexing/FileBasedIndexImpl.java
@@ -1021,6 +1021,7 @@ public class FileBasedIndexImpl extends FileBasedIndex {
 
         final TIntArrayList filesSet = new TIntArrayList();
         iterateIndexableFiles(fileOrDir -> {
+          ProgressManager.checkCanceled();
           filesSet.add(((VirtualFileWithId)fileOrDir).getId());
           return true;
         }, project, SilentProgressIndicator.create());