fix silly exception when highlightQuery is provided but there are no hits; improve verbosity of build.py to list specific sources it is compiling; remove useless DateTimeUtil that was always being compiled because of mismatch package name & its source location

Author: mikemccand

build.py

@@ -353,18 +353,16 @@ def compileChangedSources(srcPath, destPath, classPath):
         classFileName = 'build/classes/%s.class' % ('%s/%s' % (root, fileName))[4:-5]
         if not os.path.exists(classFileName) or os.path.getmtime(classFileName) < os.path.getmtime('%s/%s' % (root, fileName)):
           changedSources.append('%s/%s' % (root, fileName))
+          print(f'{fileName} {classFileName}')
 
   if len(changedSources) > 0:
     cmd = ['javac', '-Xmaxerrs', '10000', '-d', destPath]
     cmd.append('-cp')
     cmd.append(':'.join(classPath))
     cmd.extend(changedSources)
-    if False:
-      print('compile sources:')
-      for fileName in changedSources:
-        print('  %s' % fileName)
-    else:
-      print('compile %d sources' % len(changedSources))
+    print(f'compile {len(changedSources)} sources:')
+    for fileName in changedSources:
+      print('  %s' % fileName)
     run(' '.join(cmd))
 
 def getCompileClassPath():

src/java/org/apache/lucene/server/handlers/SearchHandler.java

@@ -2773,7 +2773,11 @@ protected boolean scoreSubDocsAtOnce() {
                                                                 queryForHighlights,
                                                                 highlightDocIDs,
                                                                 maxPassages);
+      } else {
+        // #26: so we consume the parameter even if there are no hits
+        r.clearParam("highlightQuery");
       }
+      
       diagnostics.put("highlightTimeMS", (System.nanoTime() - t0)/1000000.);
 
       t0 = System.nanoTime();

src/java/org/apache/lucene/server/util/DateTimeUtil.java

@@ -202,6 +202,29 @@ public void testContentWithSep() throws Exception {
     }
   }
 
+  public void testHighlightQueryWithHit() throws Exception {
+    deleteAllDocs();
+
+    long gen = addDocument("{fields: {authors: ['Dr. Seuss', 'Bob Smith', 'Seuss is Fun.  Some extra content.']}}");
+    JSONObject result = send("search", "{queryText: 'authors:seuss', retrieveFields: [{field: authors, highlight: snippets, maxPassages: 1}], " +
+                             "highlightQuery: {class: TermQuery, field: authors, term: seuss}, " +
+                             "searcher: {indexGen: " + gen + "}}");
+    assertEquals(1, getInt(result, "hits.length"));
+    assertEquals(1, getInt(result, "hits[0].fields.authors.length"));
+    assertEquals("<b>Seuss</b> Bob Smith <b>Seuss</b> is Fun.  ", renderSingleHighlight(getArray(result, "hits[0].fields.authors[0].parts")));
+  }
+
+  // #26: do not throw exception if highlightQuery is provided and there are no hits!
+  public void testHighlightQueryNoHits() throws Exception {
+    deleteAllDocs();
+
+    long gen = addDocument("{fields: {authors: ['Dr. Seuss', 'Bob Smith', 'Seuss is Fun.  Some extra content.']}}");
+    JSONObject result = send("search", "{queryText: 'authors:foobar', retrieveFields: [{field: authors}], " +
+                             "highlightQuery: {class: TermQuery, field: authors, term: seuss}, " +
+                             "searcher: {indexGen: " + gen + "}}");
+    assertEquals(0, getInt(result, "hits.length"));
+  }
+
   // nocommit fixme
   /*
   public void testNonDefaultOffsetGap() throws Exception {