Ticket #110: xapian-fix-inconsistent-paging-with-sort-by-relevance-then-value.patch

matcher/multimatch.cc

@@ -2 +2 @@
  *
  * Copyright 1999,2000,2001 BrightStation PLC
  * Copyright 2001,2002 Ananova Ltd
- * Copyright 2002,2003,2004,2005,2006 Olly Betts
+ * Copyright 2002,2003,2004,2005,2006,2007 Olly Betts
  * Copyright 2003 Orange PCS Ltd
  * Copyright 2003 Sam Liddicott
  *
@@ -61 +61 @@
 
 using namespace std;
 
+const Xapian::Enquire::Internal::sort_setting REL =
+        Xapian::Enquire::Internal::REL;
+const Xapian::Enquire::Internal::sort_setting REL_VAL =
+        Xapian::Enquire::Internal::REL_VAL;
+const Xapian::Enquire::Internal::sort_setting VAL =
+        Xapian::Enquire::Internal::VAL;
+const Xapian::Enquire::Internal::sort_setting VAL_REL =
+        Xapian::Enquire::Internal::VAL_REL;
+
 ////////////////////////////////////
 // Initialisation and cleaning up //
 ////////////////////////////////////
@@ -139 +148 @@
                 rem_db->set_query(query, qlen, collapse_key, order, sort_key,
                                   sort_by, sort_value_forward, percent_cutoff,
                                   weight_cutoff, weight, *subrset);
+                bool decreasing_relevance =
+                    (sort_by == REL || sort_by == REL_VAL);
                 smatch = new RemoteSubMatch(rem_db, gatherer.get(),
-                                            sort_key != Xapian::valueno(-1));
+                                            !decreasing_relevance);
             } else {
 #endif /* XAPIAN_HAS_REMOTE_BACKEND */
                 smatch = new LocalSubMatch(subdb, query, qlen, *subrset, gatherer.get(), weight);
@@ -417 +428 @@
 
         DEBUGLINE(MATCH, "Candidate document id " << did << " wt " << wt);
         Xapian::Internal::MSetItem new_item(wt, did);
-        if (sort_key != Xapian::valueno(-1)) {
+        if (sort_by != REL) {
             const unsigned int multiplier = db.internal.size();
             Assert(multiplier != 0);
             Xapian::doccount n = (new_item.did - 1) % multiplier; // which actual database
@@ -428 +439 @@
 
         // Test if item has high enough weight (or sort key) to get into
         // proto-mset.
-        if (sort_key != Xapian::valueno(-1) || min_item.wt > 0.0)
+        if (sort_by != REL || min_item.wt > 0.0)
             if (!mcmp(new_item, min_item)) continue;
 
         Xapian::Internal::RefCntPtr<Xapian::Document::Internal> doc;
@@ -476 +487 @@
                 } else {
                     ++duplicates_found;
                     Xapian::Internal::MSetItem &old_item = oldkey->second.first;
-                    // FIXME: what about sort_key != Xapian::valueno(-1) case
-                    // here?
+                    // FIXME: what about the (sort_by != REL) case here?
                     if (mcmp(old_item, new_item)) {
                         DEBUGLINE(MATCH, "collapsem: better exists: " <<
                                   new_item.collapse_key);
@@ -495 +505 @@
 
                     // This is best match with this key so far:
                     // remove the old one from the MSet
-                    if ((sort_key == Xapian::valueno(-1) && min_item.wt <= 0.0) ||
+                    if ((sort_by != VAL && min_item.wt <= 0.0) ||
                         mcmp(old_item, min_item)) {
                         // Old one hasn't fallen out of MSet yet
                         // Scan through (unsorted) MSet looking for entry
@@ -540 +550 @@
                 pop_heap<vector<Xapian::Internal::MSetItem>::iterator,
                          MSetCmp>(items.begin(), items.end(), mcmp);
                 items.pop_back();
-                if (sort_key != Xapian::valueno(-1)) {
+                if (sort_by == REL || sort_by == REL_VAL) {
                     Xapian::weight tmp = min_item.wt;
                     min_item = items.front();
                     min_item.wt = tmp;
@@ -554 +564 @@
             } else {
                 items.push_back(new_item);
                 is_heap = false;
-                if (sort_key == Xapian::valueno(-1) && items.size() == max_msize) {
+                if (sort_by == REL && items.size() == max_msize) {
                     // We're done if this is a forward boolean match
                     // (bodgetastic, FIXME better if we can)
                     if (max_weight == 0 && sort_forward) break;