From ec56a9557dfff45b1ac090b576d7e2d41cc02b26 Mon Sep 17 00:00:00 2001
From: "Maxim.Mossienko" <Maxim.Mossienko@jetbrains.com>
Date: Fri, 11 Jul 2014 19:37:14 +0200
Subject: [PATCH] skip leading .* in reg exp used for todo pattern when
 building index: it makes sense for todo highlighting but increases matching
 due to backtracking enormously (IDEA-74104)

---
 .../impl/id/PlatformIdTableBuilding.java      |  2 +-
 .../psi/impl/cache/impl/todo/TodoIndex.java   |  2 +-
 .../com/intellij/psi/search/IndexPattern.java | 20 ++++++++++++++-----
 .../psi/impl/cache/impl/BaseFilterLexer.java  |  2 +-
 4 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/platform/editor-ui-ex/src/com/intellij/psi/impl/cache/impl/id/PlatformIdTableBuilding.java b/platform/editor-ui-ex/src/com/intellij/psi/impl/cache/impl/id/PlatformIdTableBuilding.java
index 330dcfdf5e6a..6a3dd82b237e 100644
--- a/platform/editor-ui-ex/src/com/intellij/psi/impl/cache/impl/id/PlatformIdTableBuilding.java
+++ b/platform/editor-ui-ex/src/com/intellij/psi/impl/cache/impl/id/PlatformIdTableBuilding.java
@@ -213,7 +213,7 @@ public abstract class PlatformIdTableBuilding {
       }
       OccurrenceConsumer occurrenceConsumer = new OccurrenceConsumer(null, true);
       for (IndexPattern indexPattern : indexPatterns) {
-        Pattern pattern = indexPattern.getPattern();
+        Pattern pattern = indexPattern.getOptimizedIndexingPattern();
         if (pattern != null) {
           Matcher matcher = pattern.matcher(chars);
           while (matcher.find()) {
diff --git a/platform/editor-ui-ex/src/com/intellij/psi/impl/cache/impl/todo/TodoIndex.java b/platform/editor-ui-ex/src/com/intellij/psi/impl/cache/impl/todo/TodoIndex.java
index 09b379e8078b..d955354cca7f 100644
--- a/platform/editor-ui-ex/src/com/intellij/psi/impl/cache/impl/todo/TodoIndex.java
+++ b/platform/editor-ui-ex/src/com/intellij/psi/impl/cache/impl/todo/TodoIndex.java
@@ -127,7 +127,7 @@ public class TodoIndex extends FileBasedIndexExtension<TodoIndexEntry, Integer>
 
   @Override
   public int getVersion() {
-    return 7;
+    return 8;
   }
 
   @Override
diff --git a/platform/indexing-api/src/com/intellij/psi/search/IndexPattern.java b/platform/indexing-api/src/com/intellij/psi/search/IndexPattern.java
index fc5de78f9407..96c12bda1841 100644
--- a/platform/indexing-api/src/com/intellij/psi/search/IndexPattern.java
+++ b/platform/indexing-api/src/com/intellij/psi/search/IndexPattern.java
@@ -29,6 +29,7 @@ import java.util.regex.PatternSyntaxException;
  */
 public class IndexPattern {
   @NotNull private String myPatternString;
+  private Pattern myOptimizedIndexingPattern;
   private boolean myCaseSensitive;
   private Pattern myPattern;
 
@@ -53,6 +54,10 @@ public class IndexPattern {
     return myPattern;
   }
 
+  public Pattern getOptimizedIndexingPattern() {
+    return myOptimizedIndexingPattern;
+  }
+
   public boolean isCaseSensitive() {
     return myCaseSensitive;
   }
@@ -68,16 +73,21 @@ public class IndexPattern {
   }
 
   private void compilePattern() {
-    try{
-      if (myCaseSensitive){
-        myPattern = Pattern.compile(myPatternString);
+    try {
+      int flags = 0;
+      if (!myCaseSensitive) {
+        flags = Pattern.CASE_INSENSITIVE;
       }
-      else{
-        myPattern = Pattern.compile(myPatternString, Pattern.CASE_INSENSITIVE);
+      myPattern = Pattern.compile(myPatternString, flags);
+      String optimizedPattern = myPatternString;
+      if (optimizedPattern.startsWith(".*")) {
+        optimizedPattern = optimizedPattern.substring(".*".length());
       }
+      myOptimizedIndexingPattern = Pattern.compile(optimizedPattern, flags);
     }
     catch(PatternSyntaxException e){
       myPattern = null;
+      myOptimizedIndexingPattern = null;
     }
   }
 
diff --git a/platform/indexing-impl/src/com/intellij/psi/impl/cache/impl/BaseFilterLexer.java b/platform/indexing-impl/src/com/intellij/psi/impl/cache/impl/BaseFilterLexer.java
index cc9dddf396ea..ab774d182cbb 100644
--- a/platform/indexing-impl/src/com/intellij/psi/impl/cache/impl/BaseFilterLexer.java
+++ b/platform/indexing-impl/src/com/intellij/psi/impl/cache/impl/BaseFilterLexer.java
@@ -76,7 +76,7 @@ public abstract class BaseFilterLexer extends DelegateLexer implements IdTableBu
       todoScanningState = new TodoScanningState(patterns, matchers);
 
       for (int i = 0; i < patterns.length; ++i) {
-        Pattern pattern = patterns[i].getPattern();
+        Pattern pattern = patterns[i].getOptimizedIndexingPattern();
 
         if (pattern != null) {
           matchers[i] = pattern.matcher("");