tdf#96943 sw Hide Whitespace: don't create pages for widow / orphan ...

... paragraphs that would otherwise fit nominal size of the page frame

(cherry picked from commits 6d8da2b2deb4be2182ca1852cec7eb38a4c654eb and
59ae2d11d5884ffdf77dec95d8cd2566943fd789)

Conflicts:
	sw/qa/extras/uiwriter/uiwriter.cxx

Change-Id: I90c3de9150b17c951e1ac4158babb7a71afee9ee
Reviewed-on: https://gerrit.libreoffice.org/21445
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Ashod Nakashian <ashnakash@gmail.com>
Tested-by: Ashod Nakashian <ashnakash@gmail.com>

6 files changed, 64 insertions, 27 deletions

diff --git a/sw/qa/extras/uiwriter/data/tdf96943.odt b/sw/qa/extras/uiwriter/data/tdf96943.odt
new file mode 100644
index 000000000000..1ee5b9f91ce7
--- /dev/null
+++ b/sw/qa/extras/uiwriter/data/tdf96943.odt
diff --git a/sw/qa/extras/uiwriter/uiwriter.cxx b/sw/qa/extras/uiwriter/uiwriter.cxx
index eea54dfe8fb4..bff3a4ba757d 100644
--- a/sw/qa/extras/uiwriter/uiwriter.cxx
+++ b/sw/qa/extras/uiwriter/uiwriter.cxx
@@ -173,6 +173,7 @@ public:
     void testTdf77014();
     void testTdf92648();
     void testTdf96515();
+    void testTdf96943();
     void testTdf96479();
     void testTdf96536();
 
@@ -256,6 +257,7 @@ public:
     CPPUNIT_TEST(testTdf77014);
     CPPUNIT_TEST(testTdf92648);
     CPPUNIT_TEST(testTdf96515);
+    CPPUNIT_TEST(testTdf96943);
     CPPUNIT_TEST(testTdf96479);
     CPPUNIT_TEST(testTdf96536);
     CPPUNIT_TEST_SUITE_END();
@@ -2908,6 +2910,23 @@ void SwUiWriterTest::testTdf96515()
     CPPUNIT_ASSERT_EQUAL(1, getPages());
 }
 
+void SwUiWriterTest::testTdf96943()
+{
+    // Enable hide whitespace mode.
+    SwDoc* pDoc = createDoc("tdf96943.odt");
+    SwWrtShell* pWrtShell = pDoc->GetDocShell()->GetWrtShell();
+    SwViewOption aViewOptions(*pWrtShell->GetViewOptions());
+    aViewOptions.SetHideWhitespaceMode(true);
+    pWrtShell->ApplyViewOptions(aViewOptions);
+
+    // Insert a new character at the end of the document.
+    pWrtShell->SttEndDoc(/*bStt=*/false);
+    pWrtShell->Insert("d");
+
+    // This was 2, a new page was created for the new layout line.
+    CPPUNIT_ASSERT_EQUAL(1, getPages());
+}
+
 void SwUiWriterTest::testTdf96479()
 {
     // We want to verify the empty input text field in the bookmark
diff --git a/sw/source/core/inc/pagefrm.hxx b/sw/source/core/inc/pagefrm.hxx
index 840c580ff382..2df4c1d58a37 100644
--- a/sw/source/core/inc/pagefrm.hxx
+++ b/sw/source/core/inc/pagefrm.hxx
@@ -334,6 +334,9 @@ public:
     static const vcl::Font& GetEmptyPageFont();
 
     static SwTwips GetSidebarBorderWidth( const SwViewShell* );
+
+    /// Adjust a bottom-of-page-frame - bottom-of-text-frame difference in case whitespace is hidden.
+    void HandleWhitespaceHiddenDiff(SwTwips& nDiff);
 };
 
 inline SwContentFrame *SwPageFrame::FindFirstBodyContent()
diff --git a/sw/source/core/layout/calcmove.cxx b/sw/source/core/layout/calcmove.cxx
index 21d479a79131..84daf90e8c5b 100644
--- a/sw/source/core/layout/calcmove.cxx
+++ b/sw/source/core/layout/calcmove.cxx
@@ -1522,32 +1522,12 @@ void SwContentFrame::MakeAll(vcl::RenderContext* /*pRenderContext*/)
         const long nPrtBottom = (GetUpper()->*fnRect->fnGetPrtBottom)();
         long nBottomDist = (Frame().*fnRect->fnBottomDist)(nPrtBottom);
 
-        SwViewShell* pShell = getRootFrame()->GetCurrShell();
-        if (pShell && pShell->GetViewOptions()->IsWhitespaceHidden())
-        {
-            // When whitespace is hidden, the page frame has two heights: the
-            // nominal (defined by the frame format), and the actual (which is
-            // at most the nominal height, but can be smaller in case there is
-            // no content for the whole page).
-            // The layout size is the actual one, but we want to move the
-            // content frame to a new page only in case it doesn't fit the
-            // nominal size.
-            if (nBottomDist < 0)
-            {
-                // Content frame doesn't fit the actual size, check if it fits the nominal one.
-                SwPageFrame* pPageFrame = FindPageFrame();
-                const SwFrameFormat* pPageFormat = static_cast<const SwFrameFormat*>(pPageFrame->GetRegisteredIn());
-                const Size& rPageSize = pPageFormat->GetFrameSize().GetSize();
-                long nWhitespace = rPageSize.getHeight() - pPageFrame->Frame().Height();
-                if (nWhitespace > -nBottomDist)
-                {
-                    // It does: don't move it and invalidate our page frame so
-                    // that it gets a larger height.
-                    nBottomDist = 0;
-                    pPageFrame->InvalidateSize();
-                }
-            }
-        }
+        // Hide whitespace may require not to insert a new page.
+        SwPageFrame* pPageFrame = FindPageFrame();
+        long nOldBottomDist = nBottomDist;
+        pPageFrame->HandleWhitespaceHiddenDiff(nBottomDist);
+        if (nOldBottomDist != nBottomDist)
+            pPageFrame->InvalidateSize();
 
         if( nBottomDist >= 0 )
         {
diff --git a/sw/source/core/layout/pagechg.cxx b/sw/source/core/layout/pagechg.cxx
index 34adb7a7ea4f..967ee2fe5305 100644
--- a/sw/source/core/layout/pagechg.cxx
+++ b/sw/source/core/layout/pagechg.cxx
@@ -2287,6 +2287,34 @@ bool SwPageFrame::IsOverHeaderFooterArea( const Point& rPt, FrameControlType &rC
     return false;
 }
 
+void SwPageFrame::HandleWhitespaceHiddenDiff(SwTwips& nDiff)
+{
+    SwViewShell* pShell = getRootFrame()->GetCurrShell();
+    if (pShell && pShell->GetViewOptions()->IsWhitespaceHidden())
+    {
+        // When whitespace is hidden, the page frame has two heights: the
+        // nominal (defined by the frame format), and the actual (which is
+        // at most the nominal height, but can be smaller in case there is
+        // no content for the whole page).
+        // The layout size is the actual one, but we want to move the
+        // content frame to a new page only in case it doesn't fit the
+        // nominal size.
+        if (nDiff < 0)
+        {
+            // Content frame doesn't fit the actual size, check if it fits the nominal one.
+            const SwFrameFormat* pPageFormat = static_cast<const SwFrameFormat*>(GetRegisteredIn());
+            const Size& rPageSize = pPageFormat->GetFrameSize().GetSize();
+            long nWhitespace = rPageSize.getHeight() - Frame().Height();
+            if (nWhitespace > -nDiff)
+            {
+                // It does: don't move it and invalidate our page frame so
+                // that it gets a larger height.
+                nDiff = 0;
+            }
+        }
+    }
+}
+
 SwTextGridItem const* GetGridItem(SwPageFrame const*const pPage)
 {
     if (pPage && pPage->HasGrid())
diff --git a/sw/source/core/text/widorp.cxx b/sw/source/core/text/widorp.cxx
index 11e8c7aa658b..c75a9586ef19 100644
--- a/sw/source/core/text/widorp.cxx
+++ b/sw/source/core/text/widorp.cxx
@@ -37,6 +37,7 @@
 #include "itrtxt.hxx"
 #include "sectfrm.hxx"
 #include "ftnfrm.hxx"
+#include "pagefrm.hxx"
 
 #undef WIDOWTWIPS
 
@@ -126,8 +127,14 @@ bool SwTextFrameBreak::IsInside( SwTextMargin &rLine ) const
         // The Frame has a height to fit on the page.
         SwTwips nHeight =
             (*fnRect->fnYDiff)( (m_pFrame->GetUpper()->*fnRect->fnGetPrtBottom)(), m_nOrigin );
+        SwTwips nDiff = nHeight - nLineHeight;
+
+        // Hide whitespace may require not to insert a new page.
+        SwPageFrame* pPageFrame = m_pFrame->FindPageFrame();
+        pPageFrame->HandleWhitespaceHiddenDiff(nDiff);
+
         // If everything is inside the existing frame the result is true;
-        bFit = nHeight >= nLineHeight;
+        bFit = nDiff >= 0;
 
         // --> OD #i103292#
         if ( !bFit )