[QTextCursor] Better use of the cached whiteSpace attribute

In compare to QTextEngine::atSpace(), this also handles the less-common
"white spaces" and the exceptional control codes.

Change-Id: I52878932926b7f9fe36c9dd01007963b9691fbf0
Reviewed-by: Simon Hausmann <simon.hausmann@theqtcompany.com>

4 files changed, 8 insertions, 24 deletions

diff --git a/src/gui/text/qtextcursor.cpp b/src/gui/text/qtextcursor.cpp
index a151c515a3..eb51447105 100644
--- a/src/gui/text/qtextcursor.cpp
+++ b/src/gui/text/qtextcursor.cpp
@@ -424,9 +424,9 @@ bool QTextCursorPrivate::movePosition(QTextCursor::MoveOperation op, QTextCursor
 
         // skip if already at word start
         QTextEngine *engine = layout->engine();
-        engine->attributes();
+        const QCharAttributes *attributes = engine->attributes();
         if ((relativePos == blockIt.length() - 1)
-            && (engine->atSpace(relativePos - 1) || engine->atWordSeparator(relativePos - 1)))
+            && (attributes[relativePos - 1].whiteSpace || engine->atWordSeparator(relativePos - 1)))
             return false;
 
         if (relativePos < blockIt.length()-1)
@@ -499,7 +499,7 @@ bool QTextCursorPrivate::movePosition(QTextCursor::MoveOperation op, QTextCursor
     }
     case QTextCursor::EndOfWord: {
         QTextEngine *engine = layout->engine();
-        engine->attributes();
+        const QCharAttributes *attributes = engine->attributes();
         const int len = blockIt.length() - 1;
         if (relativePos >= len)
             return false;
@@ -508,7 +508,7 @@ bool QTextCursorPrivate::movePosition(QTextCursor::MoveOperation op, QTextCursor
             while (relativePos < len && engine->atWordSeparator(relativePos))
                 ++relativePos;
         } else {
-            while (relativePos < len && !engine->atSpace(relativePos) && !engine->atWordSeparator(relativePos))
+            while (relativePos < len && !attributes[relativePos].whiteSpace && !engine->atWordSeparator(relativePos))
                 ++relativePos;
         }
         newPosition = blockIt.position() + relativePos;
diff --git a/src/gui/text/qtextengine.cpp b/src/gui/text/qtextengine.cpp
index 10a61d3c84..67a19804a3 100644
--- a/src/gui/text/qtextengine.cpp
+++ b/src/gui/text/qtextengine.cpp
@@ -2549,21 +2549,6 @@ bool QTextEngine::atWordSeparator(int position) const
     return false;
 }
 
-bool QTextEngine::atSpace(int position) const
-{
-    const QChar c = layoutData->string.at(position);
-    switch (c.unicode()) {
-    case QChar::Tabulation:
-    case QChar::Space:
-    case QChar::Nbsp:
-    case QChar::LineSeparator:
-        return true;
-    default:
-        break;
-    }
-    return false;
-}
-
 void QTextEngine::setPreeditArea(int position, const QString &preeditText)
 {
     if (preeditText.isEmpty()) {
diff --git a/src/gui/text/qtextengine_p.h b/src/gui/text/qtextengine_p.h
index 8037fd5f6d..39b9e0cb5a 100644
--- a/src/gui/text/qtextengine_p.h
+++ b/src/gui/text/qtextengine_p.h
@@ -592,7 +592,6 @@ private:
 
 public:
     bool atWordSeparator(int position) const;
-    bool atSpace(int position) const;
 
     QString elidedText(Qt::TextElideMode mode, const QFixed &width, int flags = 0, int from = 0, int count = -1) const;
 
diff --git a/src/gui/text/qtextlayout.cpp b/src/gui/text/qtextlayout.cpp
index cab9f6ae61..7da3e84041 100644
--- a/src/gui/text/qtextlayout.cpp
+++ b/src/gui/text/qtextlayout.cpp
@@ -648,10 +648,10 @@ int QTextLayout::nextCursorPosition(int oldPos, CursorMode mode) const
             while (oldPos < len && d->atWordSeparator(oldPos))
                 oldPos++;
         } else {
-            while (oldPos < len && !d->atSpace(oldPos) && !d->atWordSeparator(oldPos))
+            while (oldPos < len && !attributes[oldPos].whiteSpace && !d->atWordSeparator(oldPos))
                 oldPos++;
         }
-        while (oldPos < len && d->atSpace(oldPos))
+        while (oldPos < len && attributes[oldPos].whiteSpace)
             oldPos++;
     }
 
@@ -679,7 +679,7 @@ int QTextLayout::previousCursorPosition(int oldPos, CursorMode mode) const
         while (oldPos && !attributes[oldPos].graphemeBoundary)
             oldPos--;
     } else {
-        while (oldPos && d->atSpace(oldPos-1))
+        while (oldPos > 0 && attributes[oldPos - 1].whiteSpace)
             oldPos--;
 
         if (oldPos && d->atWordSeparator(oldPos-1)) {
@@ -687,7 +687,7 @@ int QTextLayout::previousCursorPosition(int oldPos, CursorMode mode) const
             while (oldPos && d->atWordSeparator(oldPos-1))
                 oldPos--;
         } else {
-            while (oldPos && !d->atSpace(oldPos-1) && !d->atWordSeparator(oldPos-1))
+            while (oldPos > 0 && !attributes[oldPos - 1].whiteSpace && !d->atWordSeparator(oldPos-1))
                 oldPos--;
         }
     }