2 files changed, 33 insertions, 24 deletions

diff --git a/linden/indra/llui/lllineeditor.cpp b/linden/indra/llui/lllineeditor.cpp
index fc33dcf..6994f0b 100644
--- a/linden/indra/llui/lllineeditor.cpp
+++ b/linden/indra/llui/lllineeditor.cpp
@@ -135,18 +135,14 @@ LLLineEditor::LLLineEditor(const std::string& name, const LLRect& rect,
                 mSelectAllonCommit( TRUE ),
                 mPassDelete(FALSE),
                 mReadOnly(FALSE),
+                mHaveHistory(FALSE),
                 mImage( sImage ),
                 mReplaceNewlinesWithSpaces( TRUE )
 {
         llassert( max_length_bytes > 0 );
 
-        // line history support:
-        // - initialize line history list
-        mLineHistory.insert( mLineHistory.end(), "" );
-        // - disable line history by default
-        mHaveHistory = FALSE;
-        // - reset current history line pointer
-        mCurrentHistoryLine = 0;
+        // Initialize current history line iterator
+        mCurrentHistoryLine = mLineHistory.begin();
 
         if (font)
         {
@@ -244,16 +240,31 @@ void LLLineEditor::updateHistory()
         // reset current history line number.
         // Be sure only to remember lines that are not empty and that are
         // different from the last on the list.
-        if( mHaveHistory && mText.length() && ( mLineHistory.empty() || getText() != mLineHistory.back() ) )
+        if( mHaveHistory && getLength() )
         {
-                // discard possible empty line at the end of the history
-                // inserted by setText()
-                if( !mLineHistory.back().length() )
+                if( !mLineHistory.empty() )
                 {
-                        mLineHistory.pop_back();
+                        // When not empty, last line of history should always be blank.
+                        if( mLineHistory.back().empty() )
+                        {
+                                // discard the empty line
+                                mLineHistory.pop_back();
+                        }
+                        else
+                        {
+                                LL_WARNS("") << "Last line of history was not blank." << LL_ENDL;
+                        }
                 }
-                mLineHistory.insert( mLineHistory.end(), getText() );
-                mCurrentHistoryLine = mLineHistory.size() - 1;
+
+                // Add text to history, ignoring duplicates
+                if( mLineHistory.empty() || getText() != mLineHistory.back() )
+                {
+                        mLineHistory.push_back( getText() );
+                }
+
+                // Restore the blank line and set mCurrentHistoryLine to point at it
+                mLineHistory.push_back( "" );
+                mCurrentHistoryLine = mLineHistory.end() - 1;
         }
 }
 
@@ -324,11 +335,8 @@ void LLLineEditor::setText(const LLStringExplicit &new_text)
         }
         setCursor(llmin((S32)mText.length(), getCursor()));
 
-        // Newly set text goes always in the last line of history.
-        // Possible empty strings (as with chat line) will be deleted later.
-        mLineHistory.insert( mLineHistory.end(), new_text );
         // Set current history line to end of history.
-        mCurrentHistoryLine = mLineHistory.size() - 1;
+        mCurrentHistoryLine = mLineHistory.end() - 1;
 
         mPrevText = mText;
 }
@@ -1200,9 +1208,9 @@ BOOL LLLineEditor::handleSpecialKey(KEY key, MASK mask)
         case KEY_UP:
                 if( mHaveHistory && ( MASK_CONTROL == mask ) )
                 {
-                        if( mCurrentHistoryLine > 0 )
+                        if( mCurrentHistoryLine > mLineHistory.begin() )
                         {
-                                mText.assign( mLineHistory[ --mCurrentHistoryLine ] );
+                                mText.assign( *(--mCurrentHistoryLine) );
                                 setCursor(llmin((S32)mText.length(), getCursor()));
                         }
                         else
@@ -1217,9 +1225,9 @@ BOOL LLLineEditor::handleSpecialKey(KEY key, MASK mask)
         case KEY_DOWN:
                 if( mHaveHistory  && ( MASK_CONTROL == mask ) )
                 {
-                        if( !mLineHistory.empty() && mCurrentHistoryLine < mLineHistory.size() - 1 )
+                        if( !mLineHistory.empty() && mCurrentHistoryLine < mLineHistory.end() - 1 )
                         {
-                                mText.assign( mLineHistory[ ++mCurrentHistoryLine ] );
+                                mText.assign( *(++mCurrentHistoryLine) );
                                 setCursor(llmin((S32)mText.length(), getCursor()));
                         }
                         else
diff --git a/linden/indra/llui/lllineeditor.h b/linden/indra/llui/lllineeditor.h
index a670b21..f7cff8f 100644
--- a/linden/indra/llui/lllineeditor.h
+++ b/linden/indra/llui/lllineeditor.h
@@ -259,8 +259,9 @@ protected:
 
         // line history support:
         BOOL            mHaveHistory;                           // flag for enabled line history
-        std::vector<std::string> mLineHistory;          // line history storage
-        U32                     mCurrentHistoryLine;            // currently browsed history line
+        typedef std::vector<std::string>        line_history_t;
+        line_history_t                          mLineHistory;                   // line history storage
+        line_history_t::iterator        mCurrentHistoryLine;    // currently browsed history line
 
         LLViewBorder* mBorder;
         const LLFontGL* mGLFont;