Add TextDimensions

textview.go

@@ -1317,3 +1317,12 @@ func (t *TextView) MouseHandler() func(action MouseAction, event *tcell.EventMou
 		return
 	})
 }
+
+// TextDimensions returns the number of lines in the text buffer and the length
+// of the longest line in the buffer. This is the dimensions of the text buffer.
+// This is not the dimensions of the TextView on the screen.
+func (t *TextView) TextDimensions() (int, int) {
+	t.Lock()
+	defer t.Unlock()
+	return t.longestLine, len(t.buffer)
+}