editeng: remove SvxLRSpaceItem::nTxtLeft

Several parts of SvxLRSpaceItem appear to maintain an invariant of the
3 members nTxtLeft/nLeftMargin/nFirstLineOffset: nLeftMargin is either
equal to nTxtLeft if nFirstLineOffset is positive, otherwise equal to
nTxtLeft + nFirstLineOffset.

But not every part maintains it: there are functions SetLeftValue() and
SetLeft() which simply write into nLeftMargin regardless, and a
constructor that takes 3 separate numbers without any checks.

The constructor calls violate the invariant in 2 ways: nTxtLeft is
simply set to 0 (many cases), and one case in OutlineView::OutlineView()
that sets nTxtLeft to 2000 but the other 2 at 0.

Another odd thing is that the UNO services that expose SvxLRSpaceItem
either expose a property for MID_L_MARGIN or for MID_TXT_LMARGIN but
never both.

It looks like there are 2 distinct usages of SvxLRSpaceItem:
for anything that's applied to paragraphs, all 3 members are used;
for anything else, nTxtLeft is unused.

Try to simplify this by removing the nTxtLeft member, instead
GetTextLeft() simply calculates it.

Also assert in SetLeftValue()/SetLeft() that nFirstLineOffset is 0.

Change-Id: Ida900c6ff04ef78e92e8914beda1cc731a695b06
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/146643
Tested-by: Jenkins
Reviewed-by: Michael Stahl <michael.stahl@allotropia.de>

1 files changed, 5 insertions, 7 deletions

diff --git a/include/editeng/lrspitem.hxx b/include/editeng/lrspitem.hxx
index 8ddaa157416c..3072e385f939 100644
--- a/include/editeng/lrspitem.hxx
+++ b/include/editeng/lrspitem.hxx
@@ -49,7 +49,8 @@ SetTextLeft SetTextFirst GetLeft GetTextLeft  GetTextFirst  (What?)
 
 class EDITENG_DLLPUBLIC SvxLRSpaceItem final : public SfxPoolItem
 {
-    tools::Long    nTxtLeft;           // We spend a sal_uInt16
+    /// First-line indent always relative to GetTextLeft()
+    short   nFirstLineOffset;
     tools::Long    nLeftMargin;        // nLeft or the negative first-line indent
     tools::Long    nRightMargin;       // The unproblematic right edge
     /// The amount of extra space added to the left margin.
@@ -58,20 +59,17 @@ class EDITENG_DLLPUBLIC SvxLRSpaceItem final : public SfxPoolItem
     tools::Long    m_nRightGutterMargin;
 
     sal_uInt16  nPropFirstLineOffset, nPropLeftMargin, nPropRightMargin;
-    short   nFirstLineOffset;     // First-line indent _always_ relative to nTxtLeft
     bool        bAutoFirst;    // Automatic calculation of the first line indent
     bool        bExplicitZeroMarginValRight;
     bool        bExplicitZeroMarginValLeft;
 
-    void   AdjustLeft();        // nLeftMargin and nTxtLeft are being adjusted.
-
 public:
 
     static SfxPoolItem* CreateDefault();
 
     explicit SvxLRSpaceItem( const sal_uInt16 nId  );
     SvxLRSpaceItem( const tools::Long nLeft, const tools::Long nRight,
-                    const tools::Long nTLeft /*= 0*/, const short nOfset /*= 0*/,
+                    const short nOfset /*= 0*/,
                     const sal_uInt16 nId  );
     SvxLRSpaceItem(SvxLRSpaceItem const &) = default; // SfxPoolItem copy function dichotomy
 
@@ -97,7 +95,7 @@ public:
     // Query/direct setting of the absolute values
     tools::Long GetLeft()  const { return nLeftMargin; }
     tools::Long GetRight() const { return nRightMargin;}
-    void SetLeftValue( const tools::Long nL ) { nTxtLeft = nLeftMargin = nL; }
+    void SetLeftValue( const tools::Long nL ) { assert(nFirstLineOffset == 0); nLeftMargin = nL; }
     void SetRightValue( const tools::Long nR ) { nRightMargin = nR; }
     bool IsAutoFirst()  const { return bAutoFirst; }
     void SetAutoFirst( const bool bNew ) { bAutoFirst = bNew; }
@@ -111,7 +109,7 @@ public:
 
     // The UI/text interface:
     void SetTextLeft(const tools::Long nL, const sal_uInt16 nProp = 100);
-    tools::Long GetTextLeft() const { return nTxtLeft; }
+    tools::Long GetTextLeft() const;
 
     void SetTextFirstLineOffset(const short nF, const sal_uInt16 nProp = 100);
     short  GetTextFirstLineOffset() const { return nFirstLineOffset; }