Commit b4c911ec authored by Eric Fiselier's avatar Eric Fiselier
Browse files

[libcxx] Add a std::string_view pretty printer for libcxx. 

This adds a std::string_view pretty printer for libcxx and updates the gdb
pretty printer test.

Patch by Ali Tamur (tamur@google.com)
Reviewed as https://reviews.llvm.org/D73514
parent aa6ec19c

libcxx/test/pretty_printers/gdb_pretty_printer_test.sh.cpp

+16 −0
Original line number Diff line number Diff line
@@ -153,6 +153,21 @@ void string_test() { 
                            "\"mehmet bizim dostumuz agzi kirik testimiz\"");

}



void string_view_test() {

  std::string_view i_am_empty;

  ComparePrettyPrintToChars(i_am_empty, "std::string_view of length 0: \"\"");



  std::string source_string("to be or not to be");

  std::string_view to_be(source_string);

  ComparePrettyPrintToChars(

      to_be, "std::string_view of length 18: \"to be or not to be\"");



  const char char_arr[] = "what a wonderful world";

  std::string_view wonderful(&char_arr[7], 9);

  ComparePrettyPrintToChars(

      wonderful, "std::string_view of length 9: \"wonderful\"");

}



void u16string_test() {

  std::u16string test0 = u"Hello World";

  ComparePrettyPrintToChars(test0, "u\"Hello World\"");
@@ -613,6 +628,7 @@ int main(int argc, char* argv[]) { 
  framework_self_test();



  string_test();

  string_view_test();



  u32string_test();

  tuple_test();

libcxx/utils/gdb/libcxx/printers.py

+29 −0
Original line number Diff line number Diff line
@@ -69,6 +69,8 @@ def _remove_generics(typename): 
_common_substitutions = [

    ("std::basic_string<char, std::char_traits<char>, std::allocator<char> >",

     "std::string"),

    ("std::basic_string_view<char, std::char_traits<char> >",

     "std::string_view"),

]
@@ -243,6 +245,32 @@ class StdStringPrinter(object): 
        return "string"





class StdStringViewPrinter(object):

    """Print a std::string_view."""



    def __init__(self, val):

      self.val = val



    def to_string(self):  # pylint: disable=g-bad-name

      """GDB calls this to compute the pretty-printed form."""



      ptr = self.val["__data"]

      length = self.val["__size"]

      print_length = length

      # We print more than just a simple string (i.e. we also print

      # "of length %d").  Thus we can't use the "string" display_hint,

      # and thus we have to handle "print elements" ourselves.

      # For reference sake, gdb ensures limit == None or limit > 0.

      limit = gdb.parameter("print elements")

      if limit is not None:

        print_length = min(print_length, limit)

      # FIXME: Passing ISO-8859-1 here isn't always correct.

      string = ptr.string("ISO-8859-1", "ignore", print_length)

      if length > print_length:

        string += "..."

      return "std::string_view of length %d: \"%s\"" % (length, string)





class StdUniquePtrPrinter(object):

    """Print a std::unique_ptr."""
@@ -904,6 +932,7 @@ class LibcxxPrettyPrinter(object): 
        self.lookup = {

            "basic_string": StdStringPrinter,

            "string": StdStringPrinter,

            "string_view": StdStringViewPrinter,

            "tuple": StdTuplePrinter,

            "unique_ptr": StdUniquePtrPrinter,

            "shared_ptr": StdSharedPointerPrinter,