From dd48c7e91baa342a8439d0ce1f167134fa7b2cdc Mon Sep 17 00:00:00 2001
From: Alexander Zolotov <Alexander.Zolotov@jetbrains.com>
Date: Mon, 8 Dec 2014 18:50:34 +0300
Subject: [PATCH] Prefer live template among other exact matched elements

---
 .../completion/JavaAutoPopupTest.groovy       | 15 ++++++++++++++
 .../completion/CompletionLookupArranger.java  | 20 +++++++++++++------
 2 files changed, 29 insertions(+), 6 deletions(-)

diff --git a/java/java-tests/testSrc/com/intellij/codeInsight/completion/JavaAutoPopupTest.groovy b/java/java-tests/testSrc/com/intellij/codeInsight/completion/JavaAutoPopupTest.groovy
index ce00ff76ee67..3c077f1ca801 100644
--- a/java/java-tests/testSrc/com/intellij/codeInsight/completion/JavaAutoPopupTest.groovy
+++ b/java/java-tests/testSrc/com/intellij/codeInsight/completion/JavaAutoPopupTest.groovy
@@ -1115,6 +1115,21 @@ public class UTest {
     assert myFixture.lookupElementStrings == ['new', 'nextWord']
   }
 
+  public void testExactMatchesTemplateFirst() {
+    LiveTemplateCompletionContributor.setShowTemplatesInTests(true, getTestRootDisposable())
+    myFixture.configureByText("a.java", """
+public class Test {
+    void itar() {}
+
+    void foo() {
+        ita<caret>
+    }
+}""")
+    type 'r'
+    assert myFixture.lookupElementStrings == ['itar', 'itar']
+    assert myFixture.lookup.currentItem instanceof LiveTemplateLookupElement
+  }
+
   public void testUpdatePrefixMatchingOnTyping() {
     myFixture.addClass("class CertificateEncodingException {}")
     myFixture.addClass("class CertificateException {}")
diff --git a/platform/lang-impl/src/com/intellij/codeInsight/completion/CompletionLookupArranger.java b/platform/lang-impl/src/com/intellij/codeInsight/completion/CompletionLookupArranger.java
index 1772ac77d451..a676dd225980 100644
--- a/platform/lang-impl/src/com/intellij/codeInsight/completion/CompletionLookupArranger.java
+++ b/platform/lang-impl/src/com/intellij/codeInsight/completion/CompletionLookupArranger.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2009 JetBrains s.r.o.
+ * Copyright 2000-2014 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -339,17 +339,25 @@ public class CompletionLookupArranger extends LookupArranger {
     }
 
     String selectedText = lookup.getEditor().getSelectionModel().getSelectedText();
+    int exactMatchIndex = -1;
     for (int i = 0; i < items.size(); i++) {
       LookupElement item = items.get(i);
-      boolean isTemplate = isLiveTemplate(item);
-      if (isPrefixItem(lookup, item, true) && !isTemplate ||
+      boolean isSuddenLiveTemplate = isSuddenLiveTemplate(item);
+      if (isPrefixItem(lookup, item, true) && !isSuddenLiveTemplate ||
           item.getLookupString().equals(selectedText)) {
-        return i;
+        
+        if (exactMatchIndex == -1 || item instanceof LiveTemplateLookupElement) {
+          // prefer most recent item or LiveTemplate item
+          exactMatchIndex = i;
+        }
       }
-      if (i == 0 && isTemplate && items.size() > 1 && !CompletionServiceImpl.isStartMatch(items.get(1), lookup)) {
+      else if (i == 0 && isSuddenLiveTemplate && items.size() > 1 && !CompletionServiceImpl.isStartMatch(items.get(1), lookup)) {
         return 0;
       }
     }
+    if (exactMatchIndex >= 0) {
+      return exactMatchIndex;
+    }
 
     return Math.max(0, ContainerUtil.indexOfIdentity(items, mostRelevant));
   }
@@ -370,7 +378,7 @@ public class CompletionLookupArranger extends LookupArranger {
   }
 
 
-  private static boolean isLiveTemplate(LookupElement element) {
+  private static boolean isSuddenLiveTemplate(LookupElement element) {
     return element instanceof LiveTemplateLookupElement && ((LiveTemplateLookupElement)element).sudden;
   }