From 79414d2b72631c82cf76235cc61e2efd812e7cc1 Mon Sep 17 00:00:00 2001
From: Yonik Seeley <yonik@apache.org>
Date: Fri, 8 May 2009 20:25:07 +0000
Subject: [PATCH] SOLR-1078: WDF - treat non-spacing marks,etc like letters

git-svn-id: https://svn.apache.org/repos/asf/lucene/solr/trunk@773085 13f79535-47bb-0310-9956-ffa450edef68
---
 CHANGES.txt                                   |  4 ++
 .../solr/analysis/WordDelimiterFilter.java    | 55 +++++++++++++++----
 .../analysis/TestWordDelimiterFilter.java     | 33 +++++++++++
 3 files changed, 82 insertions(+), 10 deletions(-)

diff --git a/CHANGES.txt b/CHANGES.txt
index d1385bcec50..78df7c32bda 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -361,6 +361,10 @@ Bug Fixes
 
 44. SOLR-1141: NullPointerException during snapshoot command in java based replication (Jian Han Guo, shalin)
 
+45. SOLR-1078: Fixes to WordDelimiterFilter to avoid splitting or dropping
+    international non-letter characters such as non spacing marks. (yonik)
+
+
 Other Changes
 ----------------------
  1. Upgraded to Lucene 2.4.0 (yonik)
diff --git a/src/java/org/apache/solr/analysis/WordDelimiterFilter.java b/src/java/org/apache/solr/analysis/WordDelimiterFilter.java
index 1818b74c06e..ad4310e0be4 100644
--- a/src/java/org/apache/solr/analysis/WordDelimiterFilter.java
+++ b/src/java/org/apache/solr/analysis/WordDelimiterFilter.java
@@ -242,15 +242,51 @@ final class WordDelimiterFilter extends TokenFilter {
     this(in, defaultWordDelimTable, generateWordParts, generateNumberParts, catenateWords, catenateNumbers, catenateAll, 1, 0, 1, null);
   }
 
+
   int charType(int ch) {
     if (ch<charTypeTable.length) {
       return charTypeTable[ch];
-    } else if (Character.isLowerCase(ch)) {
-      return LOWER;
-    } else if (Character.isLetter(ch)) {
-      return UPPER;
-    } else {
-      return SUBWORD_DELIM;
+    }
+    switch (Character.getType(ch)) {
+      case Character.UPPERCASE_LETTER: return UPPER;
+      case Character.LOWERCASE_LETTER: return LOWER;
+
+      case Character.TITLECASE_LETTER:
+      case Character.MODIFIER_LETTER:
+      case Character.OTHER_LETTER:
+      case Character.NON_SPACING_MARK:
+      case Character.ENCLOSING_MARK:  // depends what it encloses?
+      case Character.COMBINING_SPACING_MARK:
+        return ALPHA; 
+
+      case Character.DECIMAL_DIGIT_NUMBER:
+      case Character.LETTER_NUMBER:
+      case Character.OTHER_NUMBER:
+        return DIGIT;
+
+      // case Character.SPACE_SEPARATOR:
+      // case Character.LINE_SEPARATOR:
+      // case Character.PARAGRAPH_SEPARATOR:
+      // case Character.CONTROL:
+      // case Character.FORMAT:
+      // case Character.PRIVATE_USE:
+
+      case Character.SURROGATE:  // prevent splitting
+        return ALPHA|DIGIT;  
+
+      // case Character.DASH_PUNCTUATION:
+      // case Character.START_PUNCTUATION:
+      // case Character.END_PUNCTUATION:
+      // case Character.CONNECTOR_PUNCTUATION:
+      // case Character.OTHER_PUNCTUATION:
+      // case Character.MATH_SYMBOL:
+      // case Character.CURRENCY_SYMBOL:
+      // case Character.MODIFIER_SYMBOL:
+      // case Character.OTHER_SYMBOL:
+      // case Character.INITIAL_QUOTE_PUNCTUATION:
+      // case Character.FINAL_QUOTE_PUNCTUATION:
+
+      default: return SUBWORD_DELIM;
     }
   }
 
@@ -348,7 +384,7 @@ final class WordDelimiterFilter extends TokenFilter {
 
         while (pos< len) {
 
-          if (type!=lastType) {
+          if ((type & lastType)==0) {  // no overlap in character type
             // check and remove "'s" from the end of a token.
             // the pattern to check for is
             //   ALPHA "'" ("s"|"S") (SUBWORD_DELIM | END)
@@ -389,9 +425,8 @@ final class WordDelimiterFilter extends TokenFilter {
             if (splitOnCaseChange == 0 && 
                 (lastType & ALPHA) != 0 && (type & ALPHA) != 0) {
               // ALPHA->ALPHA: always ignore if case isn't considered.
-
-            } else if ((lastType & UPPER)!=0 && (type & LOWER)!=0) {
-              // UPPER->LOWER: Don't split
+            } else if ((lastType & UPPER)!=0 && (type & ALPHA)!=0) {
+              // UPPER->letter: Don't split
             } else if(splitOnNumerics == 0 &&
                 ( ((lastType &  ALPHA) != 0 && (type & DIGIT) != 0) || ((lastType &  DIGIT) != 0 && (type & ALPHA) != 0) ) ) {
               // ALPHA->NUMERIC, NUMERIC->ALPHA :Don't split
diff --git a/src/test/org/apache/solr/analysis/TestWordDelimiterFilter.java b/src/test/org/apache/solr/analysis/TestWordDelimiterFilter.java
index dda71ea173e..805c81ab75e 100644
--- a/src/test/org/apache/solr/analysis/TestWordDelimiterFilter.java
+++ b/src/test/org/apache/solr/analysis/TestWordDelimiterFilter.java
@@ -327,4 +327,37 @@ public class TestWordDelimiterFilter extends AbstractSolrTestCase {
     );
   }
 
+
+  public void doSplit(final String input, String... output) throws Exception {
+    WordDelimiterFilter wdf = new WordDelimiterFilter(new TokenStream() {
+      boolean done=false;
+      @Override
+      public Token next() throws IOException {
+        if (done) return null;
+        done = true;
+        return new Token(input,0,input.length());
+      }
+    }
+            ,1,1,0,0,0
+    );
+
+    for(String expected : output) {
+      Token t = wdf.next();
+      assertEquals(expected, t.term());
+    }
+
+    assertEquals(null, wdf.next());
+  }
+
+  public void testSplits() throws Exception {
+    doSplit("basic-split","basic","split");
+    doSplit("camelCase","camel","Case");
+
+    // non-space marking symbol shouldn't cause split
+    // this is an example in Thai    
+    doSplit("\u0e1a\u0e49\u0e32\u0e19","\u0e1a\u0e49\u0e32\u0e19");
+
+
+  }
+
 }