Add a unittest case of ReplaceStringPlaceholders()

base/string_util.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/string_util.h"
 
 #include "build/build_config.h"
 
 #include <ctype.h>
 #include <errno.h>
@@ skipping 797 matching lines @@
 }
 
 string16 JoinString(const std::vector<string16>& parts, char16 sep) {
   return JoinStringT(parts, sep);
 }
 
 template<class FormatStringType, class OutStringType>
 OutStringType DoReplaceStringPlaceholders(const FormatStringType& format_string,
     const std::vector<OutStringType>& subst, std::vector<size_t>* offsets) {
   size_t substitutions = subst.size();
-  DCHECK(substitutions < 10);
 
   size_t sub_length = 0;
   for (typename std::vector<OutStringType>::const_iterator iter = subst.begin();
        iter != subst.end(); ++iter) {
     sub_length += iter->length();
   }
 
   OutStringType formatted;
   formatted.reserve(format_string.length() + sub_length);
 
   std::vector<ReplacementOffset> r_offsets;
   for (typename FormatStringType::const_iterator i = format_string.begin();
        i != format_string.end(); ++i) {
     if ('$' == *i) {
       if (i + 1 != format_string.end()) {
         ++i;
         DCHECK('$' == *i || '1' <= *i) << "Invalid placeholder: " << *i;
         if ('$' == *i) {
           while (i != format_string.end() && '$' == *i) {
             formatted.push_back('$');
             ++i;
           }
           --i;
         } else {
-          uintptr_t index = *i - '1';
+          uintptr_t index = 0;
+          while (i != format_string.end() && '0' <= *i && *i <= '9') {
+            index *= 10;
+            index += *i - '0';
+            ++i;
+          }
+          --i;
+          index -= 1;
           if (offsets) {
             ReplacementOffset r_offset(index,
                 static_cast<int>(formatted.size()));
             r_offsets.insert(std::lower_bound(r_offsets.begin(),
                                               r_offsets.end(),
                                               r_offset,
                                               &CompareParameter),
                              r_offset);
           }
           if (index < substitutions)
@@ skipping 218 matching lines @@
 }
 
 }  // namespace
 
 size_t base::strlcpy(char* dst, const char* src, size_t dst_size) {
   return lcpyT<char>(dst, src, dst_size);
 }
 size_t base::wcslcpy(wchar_t* dst, const wchar_t* src, size_t dst_size) {
   return lcpyT<wchar_t>(dst, src, dst_size);
 }