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Posted to commits@lucene.apache.org by ho...@apache.org on 2015/08/04 01:13:23 UTC

svn commit: r1693979 - in /lucene/dev/trunk: lucene/ lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/ lucene/queries/src/test/org/apache/lucene/queries/function/ solr/core/src/test/org/apache/solr/cloud/ solr/core/src/test/org/ap...

Author: hossman
Date: Mon Aug  3 23:13:22 2015
New Revision: 1693979

URL: http://svn.apache.org/r1693979
Log:
LUCENE-6609: Add getSortField impls to many subclasses of FieldCacheSource which return the most direct SortField implementation

Modified:
    lucene/dev/trunk/lucene/CHANGES.txt
    lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/DoubleFieldSource.java
    lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/FloatFieldSource.java
    lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/IntFieldSource.java
    lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/LongFieldSource.java
    lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/SortedSetFieldSource.java
    lucene/dev/trunk/lucene/queries/src/test/org/apache/lucene/queries/function/TestFunctionQuerySort.java
    lucene/dev/trunk/lucene/queries/src/test/org/apache/lucene/queries/function/TestSortedSetFieldSource.java
    lucene/dev/trunk/solr/core/src/test/org/apache/solr/cloud/DistribCursorPagingTest.java
    lucene/dev/trunk/solr/core/src/test/org/apache/solr/search/function/SortByFunctionTest.java

Modified: lucene/dev/trunk/lucene/CHANGES.txt
URL: http://svn.apache.org/viewvc/lucene/dev/trunk/lucene/CHANGES.txt?rev=1693979&r1=1693978&r2=1693979&view=diff
==============================================================================
--- lucene/dev/trunk/lucene/CHANGES.txt (original)
+++ lucene/dev/trunk/lucene/CHANGES.txt Mon Aug  3 23:13:22 2015
@@ -370,6 +370,11 @@ Changes in Runtime Behavior
   TestEarlyTerminatingSortingCollector.testTerminatedEarly test added.
   (Christine Poerschke)
 
+* LUCENE-6609: Add getSortField impls to many subclasses of FieldCacheSource which return
+  the most direct SortField implementation.  In many trivial sort by ValueSource usages, this
+  will result in less RAM, and more precise sorting of extreme values due to no longer
+  converting to double. (hossman)
+
 Optimizations
 
 * LUCENE-6548: Some optimizations for BlockTree's intersect with very

Modified: lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/DoubleFieldSource.java
URL: http://svn.apache.org/viewvc/lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/DoubleFieldSource.java?rev=1693979&r1=1693978&r2=1693979&view=diff
==============================================================================
--- lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/DoubleFieldSource.java (original)
+++ lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/DoubleFieldSource.java Mon Aug  3 23:13:22 2015
@@ -26,6 +26,8 @@ import org.apache.lucene.index.DocValues
 import org.apache.lucene.index.NumericDocValues;
 import org.apache.lucene.queries.function.FunctionValues;
 import org.apache.lucene.queries.function.docvalues.DoubleDocValues;
+import org.apache.lucene.search.SortField;
+import org.apache.lucene.search.SortField.Type;
 import org.apache.lucene.util.Bits;
 import org.apache.lucene.util.mutable.MutableValue;
 import org.apache.lucene.util.mutable.MutableValueDouble;
@@ -46,6 +48,11 @@ public class DoubleFieldSource extends F
   }
 
   @Override
+  public SortField getSortField(boolean reverse) {
+    return new SortField(field, Type.DOUBLE, reverse);
+  }
+  
+  @Override
   public FunctionValues getValues(Map context, LeafReaderContext readerContext) throws IOException {
     final NumericDocValues arr = DocValues.getNumeric(readerContext.reader(), field);
     final Bits valid = DocValues.getDocsWithField(readerContext.reader(), field);

Modified: lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/FloatFieldSource.java
URL: http://svn.apache.org/viewvc/lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/FloatFieldSource.java?rev=1693979&r1=1693978&r2=1693979&view=diff
==============================================================================
--- lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/FloatFieldSource.java (original)
+++ lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/FloatFieldSource.java Mon Aug  3 23:13:22 2015
@@ -25,6 +25,8 @@ import org.apache.lucene.index.DocValues
 import org.apache.lucene.index.NumericDocValues;
 import org.apache.lucene.queries.function.FunctionValues;
 import org.apache.lucene.queries.function.docvalues.FloatDocValues;
+import org.apache.lucene.search.SortField;
+import org.apache.lucene.search.SortField.Type;
 import org.apache.lucene.util.Bits;
 import org.apache.lucene.util.mutable.MutableValue;
 import org.apache.lucene.util.mutable.MutableValueFloat;
@@ -45,6 +47,11 @@ public class FloatFieldSource extends Fi
   }
 
   @Override
+  public SortField getSortField(boolean reverse) {
+    return new SortField(field, Type.FLOAT, reverse);
+  }
+  
+  @Override
   public FunctionValues getValues(Map context, LeafReaderContext readerContext) throws IOException {
     final NumericDocValues arr = DocValues.getNumeric(readerContext.reader(), field);
     final Bits valid = DocValues.getDocsWithField(readerContext.reader(), field);

Modified: lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/IntFieldSource.java
URL: http://svn.apache.org/viewvc/lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/IntFieldSource.java?rev=1693979&r1=1693978&r2=1693979&view=diff
==============================================================================
--- lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/IntFieldSource.java (original)
+++ lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/IntFieldSource.java Mon Aug  3 23:13:22 2015
@@ -25,6 +25,8 @@ import org.apache.lucene.index.DocValues
 import org.apache.lucene.index.NumericDocValues;
 import org.apache.lucene.queries.function.FunctionValues;
 import org.apache.lucene.queries.function.docvalues.IntDocValues;
+import org.apache.lucene.search.SortField;
+import org.apache.lucene.search.SortField.Type;
 import org.apache.lucene.util.Bits;
 import org.apache.lucene.util.mutable.MutableValue;
 import org.apache.lucene.util.mutable.MutableValueInt;
@@ -44,7 +46,11 @@ public class IntFieldSource extends Fiel
     return "int(" + field + ')';
   }
 
-
+  @Override
+  public SortField getSortField(boolean reverse) {
+    return new SortField(field, Type.INT, reverse);
+  }
+  
   @Override
   public FunctionValues getValues(Map context, LeafReaderContext readerContext) throws IOException {
     final NumericDocValues arr = DocValues.getNumeric(readerContext.reader(), field);

Modified: lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/LongFieldSource.java
URL: http://svn.apache.org/viewvc/lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/LongFieldSource.java?rev=1693979&r1=1693978&r2=1693979&view=diff
==============================================================================
--- lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/LongFieldSource.java (original)
+++ lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/LongFieldSource.java Mon Aug  3 23:13:22 2015
@@ -25,6 +25,8 @@ import org.apache.lucene.index.DocValues
 import org.apache.lucene.index.NumericDocValues;
 import org.apache.lucene.queries.function.FunctionValues;
 import org.apache.lucene.queries.function.docvalues.LongDocValues;
+import org.apache.lucene.search.SortField;
+import org.apache.lucene.search.SortField.Type;
 import org.apache.lucene.util.Bits;
 import org.apache.lucene.util.mutable.MutableValue;
 import org.apache.lucene.util.mutable.MutableValueLong;
@@ -57,6 +59,11 @@ public class LongFieldSource extends Fie
   }
 
   @Override
+  public SortField getSortField(boolean reverse) {
+    return new SortField(field, Type.LONG, reverse);
+  }
+  
+  @Override
   public FunctionValues getValues(Map context, LeafReaderContext readerContext) throws IOException {
     final NumericDocValues arr = DocValues.getNumeric(readerContext.reader(), field);
     final Bits valid = DocValues.getDocsWithField(readerContext.reader(), field);

Modified: lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/SortedSetFieldSource.java
URL: http://svn.apache.org/viewvc/lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/SortedSetFieldSource.java?rev=1693979&r1=1693978&r2=1693979&view=diff
==============================================================================
--- lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/SortedSetFieldSource.java (original)
+++ lucene/dev/trunk/lucene/queries/src/java/org/apache/lucene/queries/function/valuesource/SortedSetFieldSource.java Mon Aug  3 23:13:22 2015
@@ -26,7 +26,9 @@ import org.apache.lucene.index.SortedDoc
 import org.apache.lucene.index.SortedSetDocValues;
 import org.apache.lucene.queries.function.FunctionValues;
 import org.apache.lucene.queries.function.docvalues.DocTermsIndexDocValues;
+import org.apache.lucene.search.SortField;
 import org.apache.lucene.search.SortedSetSelector;
+import org.apache.lucene.search.SortedSetSortField;
 
 /**
  * Retrieves {@link FunctionValues} instances for multi-valued string based fields.
@@ -47,7 +49,12 @@ public class SortedSetFieldSource extend
     super(field);
     this.selector = selector;
   }
-
+  
+  @Override
+  public SortField getSortField(boolean reverse) {
+    return new SortedSetSortField(this.field, reverse, this.selector);
+  }
+  
   @Override
   public FunctionValues getValues(Map context, LeafReaderContext readerContext) throws IOException {
     SortedSetDocValues sortedSet = DocValues.getSortedSet(readerContext.reader(), field);

Modified: lucene/dev/trunk/lucene/queries/src/test/org/apache/lucene/queries/function/TestFunctionQuerySort.java
URL: http://svn.apache.org/viewvc/lucene/dev/trunk/lucene/queries/src/test/org/apache/lucene/queries/function/TestFunctionQuerySort.java?rev=1693979&r1=1693978&r2=1693979&view=diff
==============================================================================
--- lucene/dev/trunk/lucene/queries/src/test/org/apache/lucene/queries/function/TestFunctionQuerySort.java (original)
+++ lucene/dev/trunk/lucene/queries/src/test/org/apache/lucene/queries/function/TestFunctionQuerySort.java Mon Aug  3 23:13:22 2015
@@ -26,7 +26,12 @@ import org.apache.lucene.document.Numeri
 import org.apache.lucene.index.IndexReader;
 import org.apache.lucene.index.IndexWriterConfig;
 import org.apache.lucene.index.RandomIndexWriter;
+import org.apache.lucene.queries.function.valuesource.DoubleConstValueSource;
+import org.apache.lucene.queries.function.valuesource.DoubleFieldSource;
+import org.apache.lucene.queries.function.valuesource.FloatFieldSource;
 import org.apache.lucene.queries.function.valuesource.IntFieldSource;
+import org.apache.lucene.queries.function.valuesource.LongFieldSource;
+import org.apache.lucene.queries.function.valuesource.SumFloatFunction;
 import org.apache.lucene.search.FieldDoc;
 import org.apache.lucene.search.IndexSearcher;
 import org.apache.lucene.search.MatchAllDocsQuery;
@@ -34,13 +39,63 @@ import org.apache.lucene.search.Query;
 import org.apache.lucene.search.ScoreDoc;
 import org.apache.lucene.search.Sort;
 import org.apache.lucene.search.SortField;
+import org.apache.lucene.search.SortField.Type;
 import org.apache.lucene.search.TopDocs;
 import org.apache.lucene.store.Directory;
 import org.apache.lucene.util.LuceneTestCase;
 
 /** Test that functionquery's getSortField() actually works */
 public class TestFunctionQuerySort extends LuceneTestCase {
+  
+  public void testOptimizedFieldSourceFunctionSorting() throws IOException {
+    // index contents don't matter for this test.
+    Directory dir = newDirectory();
+    IndexWriterConfig iwc = newIndexWriterConfig(null);
+    RandomIndexWriter writer = new RandomIndexWriter(random(), dir, iwc);
+    IndexReader reader = writer.getReader();
+    writer.close();
+    IndexSearcher searcher = newSearcher(reader);
 
+    final boolean reverse = random().nextBoolean();
+    ValueSource vs;
+    SortField sf, vssf;
+
+    vs = new IntFieldSource("int_field");
+    sf = new SortField("int_field", Type.INT, reverse);
+    vssf = vs.getSortField(reverse);
+    assertEquals(sf, vssf);
+    sf = sf.rewrite(searcher);
+    vssf = vssf.rewrite(searcher);
+    assertEquals(sf, vssf);
+    
+    vs = new FloatFieldSource("float_field");
+    sf = new SortField("float_field", Type.FLOAT, reverse);
+    vssf = vs.getSortField(reverse);
+    assertEquals(sf, vssf);
+    sf = sf.rewrite(searcher);
+    vssf = vssf.rewrite(searcher);
+    assertEquals(sf, vssf);
+    
+    vs = new DoubleFieldSource("double_field");
+    sf = new SortField("double_field", Type.DOUBLE, reverse);
+    vssf = vs.getSortField(reverse);
+    assertEquals(sf, vssf);
+    sf = sf.rewrite(searcher);
+    vssf = vssf.rewrite(searcher);
+    assertEquals(sf, vssf);
+    
+    vs = new LongFieldSource("long_field");
+    sf = new SortField("long_field", Type.LONG, reverse);
+    vssf = vs.getSortField(reverse);
+    assertEquals(sf, vssf);
+    sf = sf.rewrite(searcher);
+    vssf = vssf.rewrite(searcher);
+    assertEquals(sf, vssf);
+     
+    reader.close();
+    dir.close();
+  }
+  
   public void testSearchAfterWhenSortingByFunctionValues() throws IOException {
     Directory dir = newDirectory();
     IndexWriterConfig iwc = newIndexWriterConfig(null);
@@ -66,8 +121,9 @@ public class TestFunctionQuerySort exten
     writer.close();
     IndexSearcher searcher = newSearcher(reader);
 
-    // Get ValueSource from FieldCache
-    IntFieldSource src = new IntFieldSource("value");
+    // Trivial ValueSource function that bypasses single field ValueSource sort optimization
+    ValueSource src = new SumFloatFunction(new ValueSource[] { new IntFieldSource("value"),
+                                                               new DoubleConstValueSource(1.0D) });
     // ...and make it a sort criterion
     SortField sf = src.getSortField(false).rewrite(searcher);
     Sort orderBy = new Sort(sf);

Modified: lucene/dev/trunk/lucene/queries/src/test/org/apache/lucene/queries/function/TestSortedSetFieldSource.java
URL: http://svn.apache.org/viewvc/lucene/dev/trunk/lucene/queries/src/test/org/apache/lucene/queries/function/TestSortedSetFieldSource.java?rev=1693979&r1=1693978&r2=1693979&view=diff
==============================================================================
--- lucene/dev/trunk/lucene/queries/src/test/org/apache/lucene/queries/function/TestSortedSetFieldSource.java (original)
+++ lucene/dev/trunk/lucene/queries/src/test/org/apache/lucene/queries/function/TestSortedSetFieldSource.java Mon Aug  3 23:13:22 2015
@@ -26,6 +26,9 @@ import org.apache.lucene.index.LeafReade
 import org.apache.lucene.index.DirectoryReader;
 import org.apache.lucene.index.IndexWriter;
 import org.apache.lucene.queries.function.valuesource.SortedSetFieldSource;
+import org.apache.lucene.search.IndexSearcher;
+import org.apache.lucene.search.SortField;
+import org.apache.lucene.search.SortedSetSortField;
 import org.apache.lucene.store.Directory;
 import org.apache.lucene.util.BytesRef;
 import org.apache.lucene.util.LuceneTestCase;
@@ -47,12 +50,24 @@ public class TestSortedSetFieldSource ex
     writer.close();
 
     DirectoryReader ir = DirectoryReader.open(dir);
+    IndexSearcher searcher = newSearcher(ir);
     LeafReader ar = getOnlySegmentReader(ir);
     
     ValueSource vs = new SortedSetFieldSource("value");
     FunctionValues values = vs.getValues(Collections.emptyMap(), ar.getContext());
     assertEquals("baz", values.strVal(0));
-    assertEquals("bar", values.strVal(1)); 
+    assertEquals("bar", values.strVal(1));
+
+    // test SortField optimization
+    final boolean reverse = random().nextBoolean();
+    SortField vssf = vs.getSortField(reverse);
+    SortField sf = new SortedSetSortField("value", reverse);
+    assertEquals(sf, vssf);
+
+    vssf = vssf.rewrite(searcher);
+    sf = sf.rewrite(searcher);
+    assertEquals(sf, vssf);
+      
     ir.close();
     dir.close();
   }

Modified: lucene/dev/trunk/solr/core/src/test/org/apache/solr/cloud/DistribCursorPagingTest.java
URL: http://svn.apache.org/viewvc/lucene/dev/trunk/solr/core/src/test/org/apache/solr/cloud/DistribCursorPagingTest.java?rev=1693979&r1=1693978&r2=1693979&view=diff
==============================================================================
--- lucene/dev/trunk/solr/core/src/test/org/apache/solr/cloud/DistribCursorPagingTest.java (original)
+++ lucene/dev/trunk/solr/core/src/test/org/apache/solr/cloud/DistribCursorPagingTest.java Mon Aug  3 23:13:22 2015
@@ -376,50 +376,54 @@ public class DistribCursorPagingTest ext
     assertEquals("no more docs, but cursorMark has changed", 
                  cursorMark, assertHashNextCursorMark(rsp));
 
-    // tri-level sort with more dups of primary then fit on a page
-    cursorMark = CURSOR_MARK_START;
-    params = params("q", "*:*", 
-                    "rows","2",
-                    "fl", "id",
-                    "sort", "float asc, "+intsort+" desc, id desc");
-    rsp = query(p(params, CURSOR_MARK_PARAM, cursorMark));
-    assertNumFound(10, rsp);
-    assertStartsAt(0, rsp);
-    assertDocList(rsp, 2, 9);
-    cursorMark = assertHashNextCursorMark(rsp);
-    //
-    rsp = query(p(params, CURSOR_MARK_PARAM, cursorMark));
-    assertNumFound(10, rsp); 
-    assertStartsAt(0, rsp);
-    assertDocList(rsp, 7, 4);
-    cursorMark = assertHashNextCursorMark(rsp);
-    //
-    rsp = query(p(params, CURSOR_MARK_PARAM, cursorMark));
-    assertNumFound(10, rsp); 
-    assertStartsAt(0, rsp);
-    assertDocList(rsp, 3, 8);
-    cursorMark = assertHashNextCursorMark(rsp);
-    //
-    rsp = query(p(params, CURSOR_MARK_PARAM, cursorMark));
-    assertNumFound(10, rsp); 
-    assertStartsAt(0, rsp);
-    assertDocList(rsp, 5, 6);
-    cursorMark = assertHashNextCursorMark(rsp);
-    //
-    rsp = query(p(params, CURSOR_MARK_PARAM, cursorMark));
-    assertNumFound(10, rsp);
-    assertStartsAt(0, rsp);
-    assertDocList(rsp, 1, 0);
-    cursorMark = assertHashNextCursorMark(rsp);
-    // we've exactly exhausted all the results, but solr had no way of know that
-    //
-    rsp = query(p(params, CURSOR_MARK_PARAM, cursorMark));
-    assertNumFound(10, rsp); 
-    assertStartsAt(0, rsp);
-    assertDocList(rsp);
-    assertEquals("no more docs, but cursorMark has changed", 
-                 cursorMark, assertHashNextCursorMark(rsp));
-
+    // tri-level sort with more dups of primary then fit on a page.
+    // also a function based sort using a simple function(s) on same field
+    // (order should be the same in all cases)
+    for (String primarysort : new String[] { "float", "field('float')", "sum(float,42)" }) {
+      cursorMark = CURSOR_MARK_START;
+      params = params("q", "*:*", 
+                      "rows","2",
+                      "fl", "id",
+                      "sort", primarysort + " asc, "+intsort+" desc, id desc");
+      rsp = query(p(params, CURSOR_MARK_PARAM, cursorMark));
+      assertNumFound(10, rsp);
+      assertStartsAt(0, rsp);
+      assertDocList(rsp, 2, 9);
+      cursorMark = assertHashNextCursorMark(rsp);
+      //
+      rsp = query(p(params, CURSOR_MARK_PARAM, cursorMark));
+      assertNumFound(10, rsp); 
+      assertStartsAt(0, rsp);
+      assertDocList(rsp, 7, 4);
+      cursorMark = assertHashNextCursorMark(rsp);
+      //
+      rsp = query(p(params, CURSOR_MARK_PARAM, cursorMark));
+      assertNumFound(10, rsp); 
+      assertStartsAt(0, rsp);
+      assertDocList(rsp, 3, 8);
+      cursorMark = assertHashNextCursorMark(rsp);
+      //
+      rsp = query(p(params, CURSOR_MARK_PARAM, cursorMark));
+      assertNumFound(10, rsp); 
+      assertStartsAt(0, rsp);
+      assertDocList(rsp, 5, 6);
+      cursorMark = assertHashNextCursorMark(rsp);
+      //
+      rsp = query(p(params, CURSOR_MARK_PARAM, cursorMark));
+      assertNumFound(10, rsp);
+      assertStartsAt(0, rsp);
+      assertDocList(rsp, 1, 0);
+      cursorMark = assertHashNextCursorMark(rsp);
+      // we've exactly exhausted all the results, but solr had no way of know that
+      //
+      rsp = query(p(params, CURSOR_MARK_PARAM, cursorMark));
+      assertNumFound(10, rsp); 
+      assertStartsAt(0, rsp);
+      assertDocList(rsp);
+      assertEquals("no more docs, but cursorMark has changed", 
+                   cursorMark, assertHashNextCursorMark(rsp));
+    }
+    
     // trivial base case: rows bigger then number of matches
     cursorMark = CURSOR_MARK_START;
     params = params("q", "id:3 id:7", 

Modified: lucene/dev/trunk/solr/core/src/test/org/apache/solr/search/function/SortByFunctionTest.java
URL: http://svn.apache.org/viewvc/lucene/dev/trunk/solr/core/src/test/org/apache/solr/search/function/SortByFunctionTest.java?rev=1693979&r1=1693978&r2=1693979&view=diff
==============================================================================
--- lucene/dev/trunk/solr/core/src/test/org/apache/solr/search/function/SortByFunctionTest.java (original)
+++ lucene/dev/trunk/solr/core/src/test/org/apache/solr/search/function/SortByFunctionTest.java Mon Aug  3 23:13:22 2015
@@ -36,7 +36,8 @@ public class SortByFunctionTest extends
   @Override
   public void setUp() throws Exception {
     super.setUp();
-  
+    assertU(delQ("*:*"));
+    assertU(commit());
   }
 
   public void test() throws Exception {
@@ -128,4 +129,75 @@ public class SortByFunctionTest extends
             "//result/doc[4]/int[@name='id'][.='1']"
     );
   }
+
+  /**
+   * Sort by function normally compares the double value, but if a function is specified that identifies
+   * a single field, we should use the underlying field's SortField to save of a lot of type converstion 
+   * (and RAM), and keep the sort precision as high as possible
+   */
+  public void testFieldSortSpecifiedAsFunction() throws Exception {
+    final long A = Long.MIN_VALUE;
+    final long B = A + 1L;
+    final long C = B + 1L;
+    
+    final long Z = Long.MAX_VALUE;
+    final long Y = Z - 1L;
+    final long X = Y - 1L;
+    
+    // test is predicated on the idea that if long -> double converstion is happening under the hood
+    // then we lose precision in sorting; so lets sanity check that our JVM isn't doing something wacky
+    // in converstion that violates the principle of the test
+    
+    assertEquals("WTF? small longs cast to double aren't equivilent?",
+                 (double)A, (double)B, 0.0D);
+    assertEquals("WTF? small longs cast to double aren't equivilent?",
+                 (double)A, (double)C, 0.0D);
+    
+    assertEquals("WTF? big longs cast to double aren't equivilent?",
+                 (double)Z, (double)Y, 0.0D);
+    assertEquals("WTF? big longs cast to double aren't equivilent?",
+                 (double)Z, (double)X, 0.0D);
+    
+    int docId = 0;
+    for (int i = 0; i < 3; i++) {
+      assertU(adoc(sdoc("id", ++docId, "primary_tl1", X, "secondary_tl1", i,
+                        "multi_l_dv", X, "multi_l_dv", A)));
+      assertU(adoc(sdoc("id", ++docId, "primary_tl1", Y, "secondary_tl1", i,
+                        "multi_l_dv", Y, "multi_l_dv", B)));
+      assertU(adoc(sdoc("id", ++docId, "primary_tl1", Z, "secondary_tl1", i,
+                        "multi_l_dv", Z, "multi_l_dv", C)));
+    }
+    assertU(commit());
+
+    // all of these sorts should result in the exact same order
+    for (String primarySort : new String[] { "primary_tl1", "field(primary_tl1)",
+                                             "field(multi_l_dv,max)", "field(multi_l_dv,min)" }) {
+      assertQ(req("q", "*:*",
+                  "sort", primarySort + " asc, secondary_tl1 asc")
+              , "//*[@numFound='9']"
+              //
+              , "//result/doc[1]/long[@name='primary_tl1'][.='"+X+"']"
+              , "//result/doc[1]/long[@name='secondary_tl1'][.='0']"
+              , "//result/doc[2]/long[@name='primary_tl1'][.='"+X+"']"
+              , "//result/doc[2]/long[@name='secondary_tl1'][.='1']"
+              , "//result/doc[3]/long[@name='primary_tl1'][.='"+X+"']"
+              , "//result/doc[3]/long[@name='secondary_tl1'][.='2']"
+              //
+              , "//result/doc[4]/long[@name='primary_tl1'][.='"+Y+"']"
+              , "//result/doc[4]/long[@name='secondary_tl1'][.='0']"
+              , "//result/doc[5]/long[@name='primary_tl1'][.='"+Y+"']"
+              , "//result/doc[5]/long[@name='secondary_tl1'][.='1']"
+              , "//result/doc[6]/long[@name='primary_tl1'][.='"+Y+"']"
+              , "//result/doc[6]/long[@name='secondary_tl1'][.='2']"
+              //
+              , "//result/doc[7]/long[@name='primary_tl1'][.='"+Z+"']"
+              , "//result/doc[7]/long[@name='secondary_tl1'][.='0']"
+              , "//result/doc[8]/long[@name='primary_tl1'][.='"+Z+"']"
+              , "//result/doc[8]/long[@name='secondary_tl1'][.='1']"
+              , "//result/doc[9]/long[@name='primary_tl1'][.='"+Z+"']"
+              , "//result/doc[9]/long[@name='secondary_tl1'][.='2']"
+              );
+    }
+  }
+  
 }