From ee786f46967d6530b2d1c19f61c06bfea330f651 Mon Sep 17 00:00:00 2001
From: peter <peter@jetbrains.com>
Date: Thu, 16 Feb 2017 17:29:33 +0100
Subject: [PATCH] fix completion in an empty custom-file-type file (EA-93679 -
 IOOBE: SegmentArrayWithData.getSegmentData)

---
 .../completion/CustomFileTypeCompletionTest.java            | 6 ++++++
 .../completion/CustomFileTypeCompletionContributor.java     | 2 ++
 2 files changed, 8 insertions(+)

diff --git a/java/java-tests/testSrc/com/intellij/codeInsight/completion/CustomFileTypeCompletionTest.java b/java/java-tests/testSrc/com/intellij/codeInsight/completion/CustomFileTypeCompletionTest.java
index dd0dc3acb1ff..2a44b1e5215a 100644
--- a/java/java-tests/testSrc/com/intellij/codeInsight/completion/CustomFileTypeCompletionTest.java
+++ b/java/java-tests/testSrc/com/intellij/codeInsight/completion/CustomFileTypeCompletionTest.java
@@ -42,6 +42,12 @@ public class CustomFileTypeCompletionTest extends LightCompletionTestCase {
     testByCount(0, new String[] { null });
   }
 
+  public void testEmptyFile() throws Throwable {
+    configureFromFileText("a.cs", "<caret>");
+    complete();
+    testByCount(1, "abstract", "x");
+  }
+
   public void testPlainTextSubstitution() throws IOException {
     FileTypeManagerEx.getInstanceEx().registerFileType(MockLanguageFileType.INSTANCE, "xxx");
     try {
diff --git a/platform/lang-impl/src/com/intellij/codeInsight/completion/CustomFileTypeCompletionContributor.java b/platform/lang-impl/src/com/intellij/codeInsight/completion/CustomFileTypeCompletionContributor.java
index 709bfd7e60eb..e4000d4e2f09 100644
--- a/platform/lang-impl/src/com/intellij/codeInsight/completion/CustomFileTypeCompletionContributor.java
+++ b/platform/lang-impl/src/com/intellij/codeInsight/completion/CustomFileTypeCompletionContributor.java
@@ -71,6 +71,8 @@ public class CustomFileTypeCompletionContributor extends CompletionContributor i
 
   private static boolean inCommentOrLiteral(CompletionParameters parameters) {
     HighlighterIterator iterator = ((EditorEx)parameters.getEditor()).getHighlighter().createIterator(parameters.getOffset());
+    if (iterator.atEnd()) return false;
+
     IElementType elementType = iterator.getTokenType();
     if (elementType == CustomHighlighterTokenType.WHITESPACE) {
       iterator.retreat();