Commit Graph

3 Commits

Author SHA1 Message Date
Kefu Chai
1cb95b8cff mutation: specialize fmt::formatter<tombstone> and fmt::formatter<shadowable_tombstone>
this is a part of a series to migrating from `operator<<(ostream&, ..)`
based formatting to fmtlib based formatting. the goal here is to enable
fmtlib to print `tombstone` and `shadowable_tombstone` without the
help of `operator<<`.

in this change, only `operator<<(ostream&, const shadowable_tombstone&)`
is dropped, and all its callers are now using fmtlib for formatting the
instances of `shadowable_tombstone` now.
`operator<<(ostream&, const tombstone&)` is preserved. as it is still
used by Boost::test for printing the operands in case the comparing tests
fail.

please note, before this change we were using a concrete string
for indent. after this change, some of the places are changed to
using fmtlib for indent.

Refs scylladb#13245

Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
2023-04-12 10:57:03 +08:00
Kefu Chai
c37f4e5252 treewide: use fmt::join() when appropriate
now that fmtlib provides fmt::join(). see
https://fmt.dev/latest/api.html#_CPPv4I0EN3fmt4joinE9join_viewIN6detail10iterator_tI5RangeEEN6detail10sentinel_tI5RangeEEERR5Range11string_view
there is not need to revent the wheel. so in this change, the homebrew
join() is replaced with fmt::join().

as fmt::join() returns an join_view(), this could improve the
performance under certain circumstances where the fully materialized
string is not needed.

please note, the goal of this change is to use fmt::join(), and this
change does not intend to improve the performance of existing
implementation based on "operator<<" unless the new implementation is
much more complicated. we will address the unnecessarily materialized
strings in a follow-up commit.

some noteworthy things related to this change:

* unlike the existing `join()`, `fmt::join()` returns a view. so we
  have to materialize the view if what we expect is a `sstring`
* `fmt::format()` does not accept a view, so we cannot pass the
  return value of `fmt::join()` to `fmt::format()`
* fmtlib does not format a typed pointer, i.e., it does not format,
  for instance, a `const std::string*`. but operator<<() always print
  a typed pointer. so if we want to format a typed pointer, we either
  need to cast the pointer to `void*` or use `fmt::ptr()`.
* fmtlib is not able to pick up the overload of
  `operator<<(std::ostream& os, const column_definition* cd)`, so we
  have to use a wrapper class of `maybe_column_definition` for printing
  a pointer to `column_definition`. since the overload is only used
  by the two overloads of
  `statement_restrictions::add_single_column_parition_key_restriction()`,
  the operator<< for `const column_definition*` is dropped.

Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
2023-03-16 20:34:18 +08:00
Avi Kivity
c5e4bf51bd Introduce mutation/ module
Move mutation-related files to a new mutation/ directory. The names
are kept in the global namespace to reduce churn; the names are
unambiguous in any case.

mutation_reader remains in the readers/ module.

mutation_partition_v2.cc was missing from CMakeLists.txt; it's added in this
patch.

This is a step forward towards librarization or modularization of the
source base.

Closes #12788
2023-02-14 11:19:03 +02:00