editeng: return ParaPortion from the list as a ref.

Change operator[] for getRef(..) method, so instead of returning
a pointer, return a reference to ParaPortion instead. This also
needs changes to the code, because we now need to make sure before
hand that the ParaPortion is really available in the list and when
this is not possible or convenient, the change the call to use
existing "SafeGetObject" instead. Add "exists" to check if the
object is available in the ParaPortionList.

In addition add "lastIndex" method to return the index of the
last ParaPortion in the list (shortcut for Count() - 1).

Change-Id: Id52c38f996468af51c75d50185110ec8502169e2
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/162071
Tested-by: Jenkins
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>

1 files changed, 19 insertions, 4 deletions

diff --git a/editeng/inc/ParagraphPortionList.hxx b/editeng/inc/ParagraphPortionList.hxx
index aa7862afa8d7..7ee252132d4e 100644
--- a/editeng/inc/ParagraphPortionList.hxx
+++ b/editeng/inc/ParagraphPortionList.hxx
@@ -38,18 +38,33 @@ public:
     tools::Long GetYOffset(const ParaPortion* pPPortion) const;
     sal_Int32 FindParagraph(tools::Long nYOffset) const;
 
-    const ParaPortion* SafeGetObject(sal_Int32 nPos) const;
-    ParaPortion* SafeGetObject(sal_Int32 nPos);
+    const ParaPortion* SafeGetObject(sal_Int32 nPos) const
+    {
+        return exists(nPos) ? maPortions[nPos].get() : nullptr;
+    }
+
+    ParaPortion* SafeGetObject(sal_Int32 nPos)
+    {
+        return exists(nPos) ? maPortions[nPos].get() : nullptr;
+    }
 
     sal_Int32 GetPos(const ParaPortion* p) const;
-    ParaPortion* operator[](sal_Int32 nPos);
-    const ParaPortion* operator[](sal_Int32 nPos) const;
+
+    ParaPortion& getRef(sal_Int32 nPosition) { return *maPortions[nPosition]; }
+    ParaPortion const& getRef(sal_Int32 nPosition) const { return *maPortions[nPosition]; }
 
     std::unique_ptr<ParaPortion> Release(sal_Int32 nPos);
     void Remove(sal_Int32 nPos);
     void Insert(sal_Int32 nPos, std::unique_ptr<ParaPortion> p);
     void Append(std::unique_ptr<ParaPortion> p);
     sal_Int32 Count() const;
+    sal_Int32 lastIndex() const { return Count() - 1; }
+
+    bool exists(sal_Int32 nPosition) const
+    {
+        return nPosition >= 0 && o3tl::make_unsigned(nPosition) < maPortions.size()
+               && maPortions[nPosition];
+    }
 
     ParaPortionContainerType::iterator begin() { return maPortions.begin(); }
     ParaPortionContainerType::iterator end() { return maPortions.end(); }