sc-perf: do not add a million empty filter entries just to sort and discard

Which can happen if an (anonymous) database range as filter range was selected
to span an entire column of which most (the tail) is empty cells. The entries
are processed to be unique anyway. This significantly shortens the time to
display the filter dialog.

Happened with attachment
http://bugs.documentfoundation.org/attachment.cgi?id=136074 of bug
https://bugs.documentfoundation.org/show_bug.cgi?id=112258

Change-Id: Ia169911d6f23611a3b3ecbf291757465f1998210
Reviewed-on: https://gerrit.libreoffice.org/42118
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Eike Rathke <erack@redhat.com>

4 files changed, 46 insertions, 6 deletions

diff --git a/sc/inc/column.hxx b/sc/inc/column.hxx
index b9b5b01f3fe2..6d2ac9e44cf1 100644
--- a/sc/inc/column.hxx
+++ b/sc/inc/column.hxx
@@ -105,6 +105,7 @@ struct ScCellValue;
 class ScDocumentImport;
 class ScHint;
 enum class ScMF;
+struct ScFilterEntries;
 
 struct ScNeededSizeOptions
 {
@@ -522,7 +523,7 @@ public:
 
     void GetFilterEntries(
         sc::ColumnBlockConstPosition& rBlockPos, SCROW nStartRow, SCROW nEndRow,
-        std::vector<ScTypedStrData>& rStrings, bool& rHasDates );
+        ScFilterEntries& rFilterEntries );
 
     bool GetDataEntries( SCROW nRow, std::set<ScTypedStrData>& rStrings, bool bLimit ) const;
 
diff --git a/sc/inc/document.hxx b/sc/inc/document.hxx
index e08378e2242c..a7b9fcdc4d17 100644
--- a/sc/inc/document.hxx
+++ b/sc/inc/document.hxx
@@ -199,6 +199,7 @@ enum class ScDBDataPortion;
 enum class ScSheetEventId;
 class BitmapEx;
 class ScColumnsRange;
+struct ScFilterEntries;
 
 namespace sc {
 
@@ -1900,12 +1901,11 @@ public:
      * database range that contains the specified cell position.
      */
     void              GetFilterEntries( SCCOL nCol, SCROW nRow,
-                                        SCTAB nTab, std::vector<ScTypedStrData>& rStrings,
-                                        bool& rHasDates);
+                                        SCTAB nTab, ScFilterEntries& rFilterEntries );
 
     SC_DLLPUBLIC void GetFilterEntriesArea( SCCOL nCol, SCROW nStartRow, SCROW nEndRow,
                                             SCTAB nTab, bool bCaseSens,
-                                            std::vector<ScTypedStrData>& rStrings, bool& rHasDates);
+                                            ScFilterEntries& rFilterEntries );
 
     void              GetDataEntries( SCCOL nCol, SCROW nRow, SCTAB nTab,
                                       std::vector<ScTypedStrData>& rStrings, bool bLimit = false );
diff --git a/sc/inc/filterentries.hxx b/sc/inc/filterentries.hxx
new file mode 100644
index 000000000000..2a8dccd99cb3
--- /dev/null
+++ b/sc/inc/filterentries.hxx
@@ -0,0 +1,39 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#ifndef SC_INC_FILTERENTRIES_HXX
+#define SC_INC_FILTERENTRIES_HXX
+
+#include <sal/config.h>
+#include "typedstrdata.hxx"
+#include <vector>
+
+struct ScFilterEntries
+{
+    std::vector<ScTypedStrData> maStrData;
+    bool                        mbHasDates;
+    bool                        mbHasEmpties;
+
+    ScFilterEntries() : mbHasDates(false), mbHasEmpties(false) {}
+
+    std::vector<ScTypedStrData>::iterator       begin()         { return maStrData.begin(); }
+    std::vector<ScTypedStrData>::iterator       end()           { return maStrData.end(); }
+    std::vector<ScTypedStrData>::const_iterator begin() const   { return maStrData.begin(); }
+    std::vector<ScTypedStrData>::const_iterator end()   const   { return maStrData.end(); }
+    std::vector<ScTypedStrData>::size_type      size()  const   { return maStrData.size(); }
+          ScTypedStrData&                       front()         { return maStrData.front(); }
+    const ScTypedStrData&                       front() const   { return maStrData.front(); }
+    bool                                        empty() const   { return maStrData.empty(); }
+    void                                        push_back( const ScTypedStrData& r ) { maStrData.push_back(r); }
+    void                                        push_back( ScTypedStrData&& r )      { maStrData.push_back(r); }
+};
+
+#endif
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */
diff --git a/sc/inc/table.hxx b/sc/inc/table.hxx
index 4c734c7d7823..10974065d571 100644
--- a/sc/inc/table.hxx
+++ b/sc/inc/table.hxx
@@ -928,8 +928,8 @@ public:
     SCSIZE      Query(const ScQueryParam& rQueryParam, bool bKeepSub);
     bool        CreateQueryParam(SCCOL nCol1, SCROW nRow1, SCCOL nCol2, SCROW nRow2, ScQueryParam& rQueryParam);
 
-    void GetFilterEntries(SCCOL nCol, SCROW nRow1, SCROW nRow2, std::vector<ScTypedStrData>& rStrings, bool& rHasDates);
-    void GetFilteredFilterEntries(SCCOL nCol, SCROW nRow1, SCROW nRow2, const ScQueryParam& rParam, std::vector<ScTypedStrData>& rStrings, bool& rHasDates );
+    void GetFilterEntries(SCCOL nCol, SCROW nRow1, SCROW nRow2, ScFilterEntries& rFilterEntries );
+    void GetFilteredFilterEntries(SCCOL nCol, SCROW nRow1, SCROW nRow2, const ScQueryParam& rParam, ScFilterEntries& rFilterEntries );
     bool GetDataEntries(SCCOL nCol, SCROW nRow, std::set<ScTypedStrData>& rStrings, bool bLimit);
 
     bool        HasColHeader( SCCOL nStartCol, SCROW nStartRow, SCCOL nEndCol, SCROW nEndRow ) const;