refactor: remove regex_escape function

include/jvalidate/detail/string.h

@@ -32,64 +32,6 @@ inline size_t length(std::string_view arg) {
   return ucs.countChar32();
 }
 
-/**
- * @brief Ensures that any codepoints/graphemes in the given regular expression
- * are wrapped in parenthesis in order to ensure that e.g. <PIRATE-EMOJI>*
- * properly matches the entire emoji multiple times, instead of just the last
- * byte of the string.
- *
- * Because we are only performing a regex search, and not matching/capturing
- * groups - we don't care that all of these extra parenthesis cause us to
- * generate new capture-groups or push some of the groups to a later point.
- *
- * @param arg A regular expression string, to be sanitized for UTF8 pattern-
- * matching.
- *
- * @returns The regular expression, with some more parenthesis added.
- */
-inline std::string regex_escape(std::string_view arg) {
-  icu::UnicodeString const ucs = icu::UnicodeString::fromUTF8(icu::StringPiece(arg));
-  // Short-circuit if there are no multi-byte codepoints or graphemes, since
-  // C++ regexes don't have any problems with those.
-  if (ucs.countChar32() == arg.size()) {
-    return std::string(arg);
-  }
-
-  UErrorCode status = U_ZERO_ERROR;
-  // createCharacterInstance directly uses new - without any special allocation
-  // rules or cleanup, since the first argument is NULL.
-  std::unique_ptr<icu::BreakIterator> iter(
-      icu::BreakIterator::createCharacterInstance(NULL, status));
-
-  // This should never occur - unless there's like an alloc error
-  if (U_FAILURE(status)) {
-    return std::string(arg);
-  }
-
-  icu::UnicodeString rval;
-  iter->setText(ucs);
-  int32_t start = iter->first();
-  int32_t end = iter->next();
-  while (end != icu::BreakIterator::DONE) {
-    // 0-or-1, 1-or-more, 0-or-more markings
-    // This could be optimized to only operate when on a multibyte character
-    if (std::strchr("?*+", ucs.charAt(end))) {
-      rval.append('(');
-      rval.append(ucs, start, end - start);
-      rval.append(')');
-      rval.append(ucs.char32At(end));
-      end = iter->next();
-    } else {
-      rval.append(ucs, start, end - start);
-    }
-    start = end;
-    end = iter->next();
-  }
-
-  std::string out;
-  return rval.toUTF8String(out);
-}
-
 inline std::string_view to_u8(std::string_view arg) { return arg; }
 
 inline std::string to_u8(std::u32string_view arg) {

include/jvalidate/validator.h

@@ -35,7 +35,6 @@ public:
   }
 
   bool search(std::string const & regex, std::string const & text) {
-    // TODO: detail::regex_escape
     auto const & re = cache_.try_emplace(regex, regex).first->second;
     return std::regex_search(text, re);
   }