tdf#156551 tdf#150606 sw: layout: only invalidate SwTabFrame if it...

... wants to move back.

In this document, the table 1709 splits across 3 columns of the section
1702 with 1 row each, and when its follows are invalidated in
CalcContent(), the later SwTabFrame::MakeAll() of the 1st follow joins
the 2nd follow and invalidates the size of the section frame, causing a
loop.

So only invalidate if that actually looks necessary.

(regression from commit 59987d3c77ec7dbf59fbea9f47cc226f4e8903f9)

Change-Id: I360c8f697a7666a19a08d8ebcabbcfa3a7cdf844
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/155452
Tested-by: Jenkins
Reviewed-by: Michael Stahl <michael.stahl@allotropia.de>
(cherry picked from commit a9b19f78f3cdcbf5c949a85b45877e903114cc54)
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/155456
Tested-by: Michael Stahl <michael.stahl@allotropia.de>

3 files changed, 29 insertions, 3 deletions

diff --git a/sw/source/core/inc/tabfrm.hxx b/sw/source/core/inc/tabfrm.hxx
index 95da935cd079..6dfa6c743a13 100644
--- a/sw/source/core/inc/tabfrm.hxx
+++ b/sw/source/core/inc/tabfrm.hxx
@@ -43,6 +43,7 @@ class SwTabFrame: public SwLayoutFrame, public SwFlowFrame
     bool m_bCalcLowers      :1; /// For stability of the content in MakeAll
     bool m_bLowersFormatted :1; /// Communication between MakeAll and Layact
     bool m_bLockBackMove    :1; /// The Master took care of the BackMove test
+    bool m_bWantBackMove    :1; /// Table wants to move back but was locked
     bool m_bResizeHTMLTable :1; /// Call the Resize of the HTMLTableLayout in the MakeAll
                                 /// This is an optimization, so that we don't have to call
                                 /// it in ContentFrame::Grow; there it might be called for
diff --git a/sw/source/core/layout/fly.cxx b/sw/source/core/layout/fly.cxx
index 6cdec269c2d9..2b6973d14e97 100644
--- a/sw/source/core/layout/fly.cxx
+++ b/sw/source/core/layout/fly.cxx
@@ -1663,7 +1663,12 @@ void CalcContent( SwLayoutFrame *pLay, bool bNoColl )
                 {
                     assert(static_cast<SwTabFrame*>(pFrame)->IsFollow());
                     static_cast<SwTabFrame*>(pFrame)->m_bLockBackMove = false;
-                    pFrame->InvalidatePos();
+                    // tdf#150606 encourage it to move back in FormatLayout()
+                    if (static_cast<SwTabFrame*>(pFrame)->m_bWantBackMove)
+                    {
+                        static_cast<SwTabFrame*>(pFrame)->m_bWantBackMove = false;
+                        pFrame->InvalidatePos();
+                    }
                 }
             }
 
diff --git a/sw/source/core/layout/tabfrm.cxx b/sw/source/core/layout/tabfrm.cxx
index 4489142e8e56..f39250dcc67b 100644
--- a/sw/source/core/layout/tabfrm.cxx
+++ b/sw/source/core/layout/tabfrm.cxx
@@ -74,6 +74,7 @@ SwTabFrame::SwTabFrame( SwTable &rTab, SwFrame* pSib )
     , m_bCalcLowers(false)
     , m_bLowersFormatted(false)
     , m_bLockBackMove(false)
+    , m_bWantBackMove(false)
     , m_bResizeHTMLTable(false)
     , m_bONECalcLowers(false)
     , m_bHasFollowFlowLine(false)
@@ -113,6 +114,7 @@ SwTabFrame::SwTabFrame( SwTabFrame &rTab )
     , m_bCalcLowers(false)
     , m_bLowersFormatted(false)
     , m_bLockBackMove(false)
+    , m_bWantBackMove(false)
     , m_bResizeHTMLTable(false)
     , m_bONECalcLowers(false)
     , m_bHasFollowFlowLine(false)
@@ -3549,9 +3551,17 @@ bool SwTabFrame::ShouldBwdMoved( SwLayoutFrame *pNewUpper, bool &rReformat )
             }
             else if (!m_bLockBackMove)
                 bMoveAnyway = true;
+            else
+            {
+                m_bWantBackMove = true;
+            }
         }
         else if (!m_bLockBackMove)
             bMoveAnyway = true;
+        else
+        {
+            m_bWantBackMove = true;
+        }
 
         if ( bMoveAnyway )
         {
@@ -3563,7 +3573,7 @@ bool SwTabFrame::ShouldBwdMoved( SwLayoutFrame *pNewUpper, bool &rReformat )
             // This frame fits into pNewUpper in case it has no space, but this
             // frame is empty.
             bFits = nSpace >= 0;
-        if (!m_bLockBackMove && bFits)
+        if (bFits)
         {
             // #i26945# - check, if follow flow line
             // contains frame, which are moved forward due to its object
@@ -3582,7 +3592,17 @@ bool SwTabFrame::ShouldBwdMoved( SwLayoutFrame *pNewUpper, bool &rReformat )
             // 'return nHeight <= nSpace' to 'return nTmpHeight < nSpace'.
             // This obviously results in problems with table frames in
             // sections. Remember: Every twip is sacred.
-            return nTmpHeight <= nSpace;
+            if (nTmpHeight <= nSpace)
+            {
+                if (m_bLockBackMove)
+                {
+                    m_bWantBackMove = true;
+                }
+                else
+                {
+                    return true;
+                }
+            }
         }
     }
     return false;