fpspreadsheet: Replace prev commit by better fix for formulas with return a blank cell being lost.

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@5752 8e941d3f-bd1b-0410-a28a-d453659cc2b4

components/fpspreadsheet/source/common/fpspreadsheet.pas

@@ -1231,7 +1231,9 @@ var
   p: Integer;
   link, txt: String;
   cell: PCell;
+  formula: String;
 begin
+  formula := ACell^.FormulaValue;
   ACell^.Flags := ACell^.Flags + [cfCalculating] - [cfCalculated];
 
   parser := TsSpreadsheetParser.Create(self);
@@ -1283,6 +1285,8 @@ begin
     parser.Free;
   end;
 
+  // Restore the formula. Could have been erased by WriteBlank or WriteText('')
+  ACell^.FormulaValue := formula;
   ACell^.Flags := ACell^.Flags + [cfCalculated] - [cfCalculating];
 end;
 
@@ -1315,7 +1319,6 @@ begin
     for cell in FCells do
       if HasFormula(cell) and (cell^.ContentType <> cctError) then
         CalcFormula(cell);
-
   finally
     dec(FWorkbook.FCalculationLock);
   end;
@@ -4823,14 +4826,16 @@ end;
 {@@ ----------------------------------------------------------------------------
   Writes an empty cell
 
-  @param  ACel      Pointer to the cell
+  @param  ACel          Pointer to the cell
   Note:   Empty cells are useful when, for example, a border line extends
           along a range of cells including empty cells.
 -------------------------------------------------------------------------------}
 procedure TsWorksheet.WriteBlank(ACell: PCell);
 begin
   if ACell <> nil then begin
-    //ACell^.FormulaValue := '';
+      ACell^.FormulaValue := '';
+    // NOTE: Erase the formula because if it would return a non-blank result
+    // this would be very confusing!
     if HasHyperlink(ACell) then
       WriteText(ACell, '')  // '' will be replaced by the hyperlink target.
     else

components/fpspreadsheet/source/common/xlsbiff2.pas

@@ -65,6 +65,7 @@ type
     procedure ReadNumber(AStream: TStream); override;
     procedure ReadRowColXF(AStream: TStream; out ARow, ACol: Cardinal; out AXF: Word); override;
     procedure ReadRowInfo(AStream: TStream); override;
+    function ReadRPNAttr(AStream: TStream; AIdentifier: Byte): Boolean; override;
     function ReadRPNFunc(AStream: TStream): Word; override;
     procedure ReadRPNSharedFormulaBase(AStream: TStream; out ARow, ACol: Cardinal); override;
     function ReadRPNTokenArraySize(AStream: TStream): Word; override;
@@ -931,6 +932,16 @@ begin
   lRow^.FormatIndex := XFToFormatIndex(xf);
 end;
 
+function TsSpreadBIFF2Reader.ReadRPNAttr(AStream: TStream; AIdentifier: Byte): Boolean;
+begin
+  Result := false;
+  case AIdentifier of
+    $01: AStream.ReadByte;   // tAttrVolatile
+    else exit;       // others not supported by fpspreadsheet --> Result = false
+  end;
+  Result := true;
+end;
+
 {@@ ----------------------------------------------------------------------------
   Reads the identifier for an RPN function with fixed argument count from the
   stream.

components/fpspreadsheet/source/common/xlscommon.pas

@@ -452,6 +452,7 @@ type
     procedure ReadRowColXF(AStream: TStream; out ARow, ACol: Cardinal; out AXF: Word); virtual;
     // Read row info
     procedure ReadRowInfo(AStream: TStream); virtual;
+    function ReadRPNAttr(AStream: TStream; AIdentifier: Byte): boolean; virtual;
     // Read the array of RPN tokens of a formula
     procedure ReadRPNCellAddress(AStream: TStream; out ARow, ACol: Cardinal;
       out AFlags: TsRelFlags); virtual;
@@ -2154,6 +2155,24 @@ begin
     FWorksheet.WriteRowInfo(rowrec.RowIndex, lRow);
 end;
 
+{@@ ----------------------------------------------------------------------------
+  Reads the special attribute of an RPN formula element.
+  Attributes are ignored by fpspreadsheet.
+  Structure is value for BIFF3 - BIFF8. Must be overridden for BIFF2.
+  Returns false if the structure is too complex for fps.
+-------------------------------------------------------------------------------}
+function TsSpreadBIFFReader.ReadRPNAttr(AStream: TStream; AIdentifier: Byte): Boolean;
+var
+  w: Word;
+begin
+  Result := false;
+  case AIdentifier of
+    $01: AStream.ReadWord;     // tAttrVolatile token
+    else exit;                 // others not supported by fps --> Result = false
+  end;
+  Result := true;
+end;
+
 {@@ ----------------------------------------------------------------------------
   Reads the cell address used in an RPN formula element.
   Evaluates the corresponding bits to distinguish between absolute and
@@ -2511,6 +2530,11 @@ begin
   while (AStream.Position < p0 + ARPNTokenArraySize) and supported do begin
     token := AStream.ReadByte;
     case token of
+      INT_EXCEL_TOKEN_TATTR:
+        begin
+          b := AStream.ReadByte;
+          supported := ReadRPNAttr(AStream, b);
+        end;
       INT_EXCEL_TOKEN_TREFV:
         begin
           ReadRPNCellAddress(AStream, r, c, flags);

components/fpspreadsheet/source/common/xlsconst.pas

@@ -34,12 +34,21 @@ const
   INT_EXCEL_TOKEN_TPAREN    = $15; // Operator in parenthesis
 
   { Constant Operand Tokens, 3.8}
-  INT_EXCEL_TOKEN_TMISSARG  = $16; //missing operand
+  INT_EXCEL_TOKEN_TMISSARG  = $16; // missing operand
-  INT_EXCEL_TOKEN_TSTR      = $17; //string
+  INT_EXCEL_TOKEN_TSTR      = $17; // string
-  INT_EXCEL_TOKEN_TERR      = $1C; //error value
+  INT_EXCEL_TOKEN_TERR      = $1C; // error value
-  INT_EXCEL_TOKEN_TBOOL     = $1D; //boolean
+  INT_EXCEL_TOKEN_TBOOL     = $1D; // boolean
-  INT_EXCEL_TOKEN_TINT      = $1E; //(unsigned) integer
+  INT_EXCEL_TOKEN_TINT      = $1E; // (unsigned) integer
-  INT_EXCEL_TOKEN_TNUM      = $1F; //floating-point
+  INT_EXCEL_TOKEN_TNUM      = $1F; // floating-point
+
+  { Control Tokens, Special Tokens, 3.10 }
+//  01H tExp Matrix formula or shared formula
+//  02H tTbl Multiple operation table
+//  15H tParen Parentheses
+//  18H tNlr Natural language reference (BIFF8)
+  INT_EXCEL_TOKEN_TATTR = $19; // tAttr Special attribute
+//  1AH tSheet Start of external sheet reference (BIFF2-BIFF4)
+//  1BH tEndSheet End of external sheet reference (BIFF2-BIFF4)
 
   { Operand Tokens }
   // _R: reference; _V: value; _A: array
@@ -259,14 +268,6 @@ const
 
   INT_EXCEL_SHEET_FUNC_HYPERLINK  = 359;  // BIFF8 only
 
-  { Control Tokens, Special Tokens }
-//  01H tExp Matrix formula or shared formula
-//  02H tTbl Multiple operation table
-//  15H tParen Parentheses
-//  18H tNlr Natural language reference (BIFF8)
-  INT_EXCEL_TOKEN_TATTR = $19; // tAttr Special attribute
-//  1AH tSheet Start of external sheet reference (BIFF2-BIFF4)
-//  1BH tEndSheet End of external sheet reference (BIFF2-BIFF4)
 
 
 implementation

components/fpspreadsheet/source/common/xlsxooxml.pas

@@ -308,6 +308,13 @@ type
     Tooltip: String;
   end;
 
+  TSharedFormulaData = class
+    Worksheet: TsWorksheet;
+    Row: Integer;
+    Col: Integer;
+    Formula: String;
+  end;
+
 const
   PATTERN_TYPES: array [TsFillStyle] of string = (
     'none',            // fsNoFill
@@ -327,7 +334,7 @@ const
     'lightDown',       // fsThinStripeDiagDown
     'darkTrellis',     // fsHatchDiag
     'lightTrellis',    // fsHatchThinDiag
-    'darkTellis',      // fsHatchTickDiag
+    'darkTellis',      // fsHatchThickDiag
     'lightGrid'        // fsHatchThinHor
     );
 
@@ -359,19 +366,25 @@ destructor TsSpreadOOXMLReader.Destroy;
 var
   j: Integer;
 begin
-  for j := FFillList.Count-1 downto 0 do TObject(FFillList[j]).Free;
+  for j := FFillList.Count-1 downto 0 do
+    TObject(FFillList[j]).Free;
   FFillList.Free;
 
-  for j := FBorderList.Count-1 downto 0 do TObject(FBorderList[j]).Free;
+  for j := FBorderList.Count-1 downto 0 do
+    TObject(FBorderList[j]).Free;
   FBorderList.Free;
 
-  for j := FHyperlinkList.Count-1 downto 0 do TObject(FHyperlinkList[j]).Free;
+  for j := FHyperlinkList.Count-1 downto 0 do
+    TObject(FHyperlinkList[j]).Free;
   FHyperlinkList.Free;
 
   for j := FSharedStrings.Count-1 downto 0 do
-    if FSharedstrings.Objects[j] <> nil then FSharedStrings.Objects[j].Free;
+    FSharedStrings.Objects[j].Free;
   FSharedStrings.Free;
-  FSharedFormulaBaseList.Free;   // Don't free items, they are worksheet cells
+
+  for j := FSharedFormulaBaseList.Count-1 downto 0 do
+    TObject(FSharedFormulaBaseList[j]).Free;
+  FSharedFormulaBaseList.Free;
 
   // FCellFormatList, FNumFormatList and FFontList are destroyed by ancestor
 
@@ -582,7 +595,9 @@ procedure TsSpreadOOXMLReader.ReadCell(ANode: TDOMNode; AWorksheet: TsWorksheet)
 var
   addr, s: String;
   rowIndex, colIndex: Cardinal;
-  cell, sharedformulabase: PCell;
+  cell: PCell;
+  lCell: TCell;
+  sharedFormulabase: TSharedFormulaData;
   datanode, tnode: TDOMNode;
   dataStr: String;
   formulaStr: String;
@@ -655,18 +670,28 @@ begin
         s := GetAttrValue(datanode, 'ref');
         if (s <> '') then      // This defines the shared formula range
         begin
-          AWorksheet.WriteFormula(cell, FormulaStr);
+          AWorksheet.WriteFormula(cell, formulaStr);
           // We store the shared formula base in the SharedFormulaBaseList.
           // The list index is identical with the 'si' attribute of the node.
-          FSharedFormulaBaseList.Add(cell);
+          sharedformulabase := TSharedFormulaData.Create;
+          sharedformulabase.Worksheet := FWorksheet;
+          sharedformulabase.Row := rowindex;
+          sharedformulabase.Col := colindex;
+          sharedformulabase.Formula := formulaStr;
+          FSharedFormulaBaseList.Add(sharedformulabase);
         end else
         begin
-          // Get index into the SharedFormulaBaseList
+          // Get index into the SharedFormulaBaseList...
           s := GetAttrValue(datanode, 'si');
           if s <> '' then
           begin
-            sharedformulabase := PCell(FSharedFormulaBaseList[StrToInt(s)]);
+            sharedformulabase := TSharedFormulaData(FSharedFormulaBaseList[StrToInt(s)]);
-            FWorksheet.CopyFormula(sharedformulabase, rowindex, colindex);
+            // ... and copy shared formula to destination cell
+            InitCell(sharedformulabase.Row, sharedformulabase.Col, lCell);
+            lCell.Formulavalue := sharedformulabase.Formula;
+            lCell.Worksheet := sharedformulabase.Worksheet;
+            FWorksheet.CopyFormula(@lCell, cell);
+            cell^.ContentType := cctFormula;
           end;
         end;
       end
@@ -681,8 +706,9 @@ begin
   s := GetAttrValue(ANode, 't');   // "t" = data type
   if (s = '') and (dataStr = '') then
   begin
+    formulaStr := cell^.FormulaValue;
     AWorksheet.WriteBlank(cell);     // this erases the formula!!!
-    if formulaStr <> '' then cell^.FormulaValue := formulaStr;
+    cell^.FormulaValue := formulaStr;
   end else
   if (s = '') or (s = 'n') then begin
     // Number or date/time, depending on format
@@ -713,10 +739,12 @@ begin
       ms.ReadBuffer(cell^.RichTextParams[0], n*SizeOf(TsRichTextParam));
     end;
   end else
-  if (s = 'str') or (s = 'inlineStr') then
+  if (s = 'str') or (s = 'inlineStr') then begin
     // literal string
-    AWorksheet.WriteText(cell, datastr)
+    formulaStr := cell^.FormulaValue;
-  else
+    AWorksheet.WriteText(cell, datastr);
+    cell^.FormulaValue := formulaStr;
+  end else
   if s = 'b' then
     // boolean
     AWorksheet.WriteBoolValue(cell, dataStr='1')