add test for suggester iterators

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1291502 13f79535-47bb-0310-9956-ffa450edef68

modules/suggest/src/test/org/apache/lucene/search/suggest/TestTermFreqIterator.java

@@ -0,0 +1,75 @@
+package org.apache.lucene.search.suggest;
+
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with this
+ * work for additional information regarding copyright ownership. The ASF
+ * licenses this file to You under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+
+import java.util.Iterator;
+import java.util.Map;
+import java.util.TreeMap;
+
+import org.apache.lucene.search.spell.TermFreqIterator;
+import org.apache.lucene.util.BytesRef;
+import org.apache.lucene.util.LuceneTestCase;
+import org.apache.lucene.util._TestUtil;
+
+public class TestTermFreqIterator extends LuceneTestCase {
+  public void testEmpty() throws Exception {
+    TermFreqArrayIterator iterator = new TermFreqArrayIterator(new TermFreq[0]);
+    TermFreqIterator wrapper = new SortedTermFreqIteratorWrapper(iterator, BytesRef.getUTF8SortedAsUnicodeComparator());
+    assertNull(wrapper.next());
+    wrapper = new UnsortedTermFreqIteratorWrapper(iterator);
+    assertNull(wrapper.next());
+  }
+  
+  public void testTerms() throws Exception {
+    int num = atLeast(10000);
+    
+    TreeMap<BytesRef,Float> sorted = new TreeMap<BytesRef,Float>();
+    TermFreq[] unsorted = new TermFreq[num];
+
+    for (int i = 0; i < num; i++) {
+      BytesRef key;
+      do {
+        key = new BytesRef(_TestUtil.randomUnicodeString(random));
+      } while (sorted.containsKey(key));
+      float value = random.nextFloat();
+      sorted.put(key, value);
+      unsorted[i] = new TermFreq(key, value);
+    }
+    
+    // test the sorted iterator wrapper
+    TermFreqIterator wrapper = new SortedTermFreqIteratorWrapper(new TermFreqArrayIterator(unsorted), BytesRef.getUTF8SortedAsUnicodeComparator());
+    Iterator<Map.Entry<BytesRef,Float>> expected = sorted.entrySet().iterator();
+    while (expected.hasNext()) {
+      Map.Entry<BytesRef,Float> entry = expected.next();
+      
+      assertEquals(entry.getKey(), wrapper.next());
+      assertEquals(entry.getValue().floatValue(), wrapper.freq(), 0F);
+    }
+    assertNull(wrapper.next());
+    
+    // test the unsorted iterator wrapper
+    wrapper = new UnsortedTermFreqIteratorWrapper(new TermFreqArrayIterator(unsorted));
+    TreeMap<BytesRef,Float> actual = new TreeMap<BytesRef,Float>();
+    BytesRef key;
+    while ((key = wrapper.next()) != null) {
+      float value = wrapper.freq();
+      actual.put(BytesRef.deepCopyOf(key), value);
+    }
+    assertEquals(sorted, actual);
+  }
+}