Merge pull request #25 from benelog/refactor-regex

Refactor to reuse java.util.regex.Pattern

src/main/java/com/github/difflib/text/DiffRowGenerator.java

@@ -49,9 +49,10 @@ import java.util.regex.Pattern;
 public class DiffRowGenerator {
 
     public static final Pattern SPLIT_BY_WORD_PATTERN = Pattern.compile("\\s+|[,.\\[\\](){}/\\\\*+\\-#]");
+    public static final Pattern WHITESPACE_PATTERN = Pattern.compile("\\s+");
 
     public static final BiPredicate<String, String> IGNORE_WHITESPACE_EQUALIZER = (original, revised)
-            -> original.trim().replaceAll("\\s+", " ").equals(revised.trim().replaceAll("\\s+", " "));
+            -> adjustWhitespace(original).equals(adjustWhitespace(revised));
 
     public static final BiPredicate<String, String> DEFAULT_EQUALIZER = Object::equals;
 
@@ -468,4 +469,8 @@ public class DiffRowGenerator {
         }
         return list;
     }
+
+    private static String adjustWhitespace(String raw) {
+        return WHITESPACE_PATTERN.matcher(raw.trim()).replaceAll(" ");
+    }
 }