Better fix for *_stringForCharacterAtIndex's missing prototype

Tests/Unit/SOGoTest.h

@@ -54,8 +54,6 @@
 
 - (BOOL) run;
 
-NSString *_stringForCharacterAtIndex(NSUInteger index, NSString *str, NSUInteger length);
-
 - (NSString*) stringFromDiffBetween: (NSString*) str1
                                 and: (NSString*) str2;
 @end

Tests/Unit/SOGoTest.m

@@ -31,6 +31,36 @@
 
 static NSString *SOGoTestAssertException = @"SOGoTestAssertException";
 
+/* Helper function for diffForString:andString */
+static NSString *_stringForCharacterAtIndex(NSUInteger index, NSString *str, NSUInteger length)
+{
+  NSString *chrStr;
+  unichar chr;
+  if (index < length)
+    {
+      chr = [str characterAtIndex: index];
+      if (isprint(chr)) 
+        {
+          chrStr = [NSString stringWithFormat: @"%c", chr];
+        }
+      else
+        {
+          if (chr == 10) 
+            chrStr = @"[NL]";
+          else if (chr == 0)
+            chrStr = @"[\0]";
+          else    
+            chrStr = [NSString stringWithFormat: @"[NP: %u]", chr];
+        }
+    }
+  else
+    {
+      chrStr = @"[none]";
+    }
+
+  return chrStr;
+}
+
 @implementation SOGoTest
 
 + (NSArray *) allTestClasses
@@ -186,36 +216,6 @@ static NSString *SOGoTestAssertException = @"SOGoTestAssertException";
   return YES;
 }
 
-/* Helper function for diffForString:andString */
-NSString *_stringForCharacterAtIndex(NSUInteger index, NSString *str, NSUInteger length)
-{
-  NSString *chrStr;
-  unichar chr;
-  if (index < length)
-    {
-      chr = [str characterAtIndex: index];
-      if (isprint(chr)) 
-        {
-          chrStr = [NSString stringWithFormat: @"%c", chr];
-        }
-      else
-        {
-          if (chr == 10) 
-            chrStr = @"[NL]";
-          else if (chr == 0)
-            chrStr = @"[\0]";
-          else    
-            chrStr = [NSString stringWithFormat: @"[NP: %u]", chr];
-        }
-    }
-  else
-    {
-      chrStr = @"[none]";
-    }
-
-  return chrStr;
-}
-
 /*
   Returns a string with a very verbose diff of the two strings.
   In case the strings are equal it returns an empty string.