Don't eliminate text completely in Ellipsize().

If the shortened text is so short there's nothing left of the original,
show one character and "...". This is standard behaviour on both
Windows and OS X, in addition to making lot of sense.

Fixes #11360.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@66874 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/ctrlcmn.cpp

@@ -402,6 +402,11 @@ wxString wxControlBase::DoEllipsizeSingleLine(const wxString& curLine, const wxD
                 calc.Init(0, 1);
                 while ( !calc.IsShortEnough() )
                     calc.RemoveFromEnd();
+
+                // always show at least one character of the string:
+                if ( calc.m_nCharsToRemove == len )
+                    return wxString(wxELLIPSE_REPLACEMENT) + curLine[len-1];
+
                 break;
             }
 
@@ -444,6 +449,15 @@ wxString wxControlBase::DoEllipsizeSingleLine(const wxString& curLine, const wxD
                     else
                         calc.RemoveFromEnd();
                 }
+
+                // Always show at least one character of the string.
+                // Additionally, if there's only one character left, prefer
+                // "a..." to "...a":
+                if ( calc.m_nCharsToRemove == len ||
+                     calc.m_nCharsToRemove == len - 1 )
+                {
+                    return curLine[0] + wxString(wxELLIPSE_REPLACEMENT);
+                }
             }
             break;
 
@@ -452,6 +466,11 @@ wxString wxControlBase::DoEllipsizeSingleLine(const wxString& curLine, const wxD
                 calc.Init(len - 1, 1);
                 while ( !calc.IsShortEnough() )
                     calc.RemoveFromStart();
+
+                // always show at least one character of the string:
+                if ( calc.m_nCharsToRemove == len )
+                    return curLine[0] + wxString(wxELLIPSE_REPLACEMENT);
+
                 break;
             }