mdebray/tvl-depot
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Export of internal Abseil changes

Browse source 
--
24162e64040e89f174531fa78fc0ff43c3a67da4 by Abseil Team <absl-team@google.com>:

Make ABSL_RETIRED_FLAG behave consistently with ABSL_FLAG.

Before the change:
ABSL_RETIRED_FLAG does not compile when there are competing ctors in the type, even when ABSL_FLAG does.

After the change:
ABSL_RETIRED_FLAG compiles when ABSL_FLAG does.

PiperOrigin-RevId: 286437395

--
870d4cb4d114813e9cefe30d26d020b0fdcdc4b4 by Tom Manshreck <shreck@google.com>:

Add docs on bind_front

PiperOrigin-RevId: 286433540

--
b0c328bd9bb64e0382f942f93b85054229dafeac by Tom Manshreck <shreck@google.com>:

Specify the format for LogSeverity flags

PiperOrigin-RevId: 286402811
GitOrigin-RevId: 24162e64040e89f174531fa78fc0ff43c3a67da4
Change-Id: I89785145d049fee49c6b9cf3357893ece9a6231c
This commit is contained in:
Abseil Team 2019-12-19 12:03:35 -08:00 committed by CJ Johnson
parent 7bd1935dcb
commit ad904b6cd3
5 changed files with 127 additions and 34 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

50
absl/base/log_severity.h
View file

@ -24,19 +24,45 @@
namespace absl {
ABSL_NAMESPACE_BEGIN
// absl::LogSeverity
//
// Four severity levels are defined. Logging APIs should terminate the program
// when a message is logged at severity `kFatal`; the other levels have no
// special semantics.
//
// Abseil flags may be defined with type `LogSeverity`. Dependency layering
// constraints require that the `AbslParseFlag` overload be declared and defined
// in the flags module rather than here. The `AbslUnparseFlag` overload is
// defined there too for consistency.
// Values other than the four defined levels (e.g. produced by `static_cast`)
// are valid, but their semantics when passed to a function, macro, or flag
// depend on the function, macro, or flag. The usual behavior is to normalize
// such values to a defined severity level, however in some cases values other
// than the defined levels are useful for comparison.
//
// The parser accepts arbitrary integers (as if the type were `int`). It also
// accepts each named enumerator, without regard for case, with or without the
// leading 'k'. For example: "kInfo", "INFO", and "info" all parse to the value
// `absl::LogSeverity::kInfo`.
// Exmaple:
//
// // Effectively disables all logging:
// SetMinLogLevel(static_cast<absl::LogSeverity>(100));
//
// Abseil flags may be defined with type `LogSeverity`. Dependency layering
// constraints require that the `AbslParseFlag()` overload be declared and
// defined in the flags library itself rather than here. The `AbslUnparseFlag()`
// overload is defined there as well for consistency.
//
// absl::LogSeverity Flag String Representation
//
// An `absl::LogSeverity` has a string representation used for parsing
// command-line flags based on the enumerator name (e.g. `kFatal`) or
// its unprefixed name (without the `k`) in any case-insensitive form. (E.g.
// "FATAL", "fatal" or "Fatal" are all valid.) Unparsing such flags produces an
// unprefixed string representation in all caps (e.g. "FATAL") or an integer.
//
// Additionally, the parser accepts arbitrary integers (as if the type were
// `int`).
//
// Examples:
//
// --my_log_level=kInfo
// --my_log_level=INFO
// --my_log_level=info
// --my_log_level=0
//
// Unparsing a flag produces the same result as `absl::LogSeverityName()` for
// the standard levels and a base-ten integer otherwise.
@ -47,6 +73,8 @@ enum class LogSeverity : int {
kFatal = 3,
};
// LogSeverities()
//
// Returns an iterable of all standard `absl::LogSeverity` values, ordered from
// least to most severe.
constexpr std::array<absl::LogSeverity, 4> LogSeverities() {
@ -54,6 +82,8 @@ constexpr std::array<absl::LogSeverity, 4> LogSeverities() {
absl::LogSeverity::kError, absl::LogSeverity::kFatal}};
}
// LogSeverityName()
//
// Returns the all-caps string representation (e.g. "INFO") of the specified
// severity level if it is one of the standard levels and "UNKNOWN" otherwise.
constexpr const char* LogSeverityName(absl::LogSeverity s) {
@ -66,6 +96,8 @@ constexpr const char* LogSeverityName(absl::LogSeverity s) {
: s == absl::LogSeverity::kFatal ? "FATAL" : "UNKNOWN";
}
// NormalizeLogSeverity()
//
// Values less than `kInfo` normalize to `kInfo`; values greater than `kFatal`
// normalize to `kError` (**NOT** `kFatal`).
constexpr absl::LogSeverity NormalizeLogSeverity(absl::LogSeverity s) {
@ -77,6 +109,8 @@ constexpr absl::LogSeverity NormalizeLogSeverity(int s) {
return absl::NormalizeLogSeverity(static_cast<absl::LogSeverity>(s));
}
// operator<<
//
// The exact representation of a streamed `absl::LogSeverity` is deliberately
// unspecified; do not rely on it.
std::ostream& operator<<(std::ostream& os, absl::LogSeverity s);

10
absl/flags/flag.h
View file

@ -384,11 +384,19 @@ ABSL_NAMESPACE_END
//
// `default_value` is only used as a double check on the type. `explanation` is
// unused.
//
// ABSL_RETIRED_FLAG support omitting the default value for default
// constructible value type, so that users can delete the code generatring this
// value.
//
// TODO(rogeeff): Return an anonymous struct instead of bool, and place it into
// the unnamed namespace.
#define ABSL_RETIRED_FLAG(type, flagname, default_value, explanation) \
ABSL_ATTRIBUTE_UNUSED static const bool ignored_##flagname = \
([] { return type(default_value); }, \
([] { \
return absl::flags_internal::MakeFromDefaultValueOrEmpty<type>( \
default_value); \
}, \
absl::flags_internal::RetiredFlag<type>(#flagname))
#endif // ABSL_FLAGS_FLAG_H_

23
absl/flags/flag_test.cc
View file

@ -486,11 +486,30 @@ TEST_F(FlagTest, TestNonDefaultConstructibleType) {
// --------------------------------------------------------------------
struct Wrapper {
Wrapper() {}
// NOLINTNEXTLINE(runtime/explicit)
Wrapper(const std::string& val) : val(val) {}
// NOLINTNEXTLINE(runtime/explicit)
template <typename T>
Wrapper(T&& t) : val(std::forward<T>(t)) {}
// NOLINTNEXTLINE(runtime/explicit)
operator std::string() const& { return val; }
std::string val;
};
} // namespace
ABSL_RETIRED_FLAG(bool, old_bool_flag, true, "old descr");
ABSL_RETIRED_FLAG(int, old_int_flag, (int)std::sqrt(10), "old descr");
ABSL_RETIRED_FLAG(std::string, old_str_flag, "", absl::StrCat("old ", "descr"));
ABSL_RETIRED_FLAG(Wrapper, old_wrapper_flag, {}, "old wrapper");
ABSL_RETIRED_FLAG(Wrapper, old_wrapper_no_default_flag, ,
"old wrapper no default");
namespace {
@ -502,6 +521,10 @@ TEST_F(FlagTest, TestRetiredFlagRegistration) {
EXPECT_FALSE(is_bool);
EXPECT_TRUE(flags::IsRetiredFlag("old_str_flag", &is_bool));
EXPECT_FALSE(is_bool);
EXPECT_TRUE(flags::IsRetiredFlag("old_wrapper_flag", &is_bool));
EXPECT_FALSE(is_bool);
EXPECT_TRUE(flags::IsRetiredFlag("old_wrapper_no_default_flag", &is_bool));
EXPECT_FALSE(is_bool);
EXPECT_FALSE(flags::IsRetiredFlag("some_other_flag", &is_bool));
}

14
absl/flags/internal/flag.h
View file

@ -416,6 +416,20 @@ T* MakeFromDefaultValue(EmptyBraces) {
return new T;
}
// MakeFromDefaultValueOrEmpty is basically the same as MakeFromDefaultValue. It
// also allows for empty macro parameter (hence no argument), which was somehow
// widely used for ABSL_RETIRED_FLAG().
template <typename T>
T* MakeFromDefaultValueOrEmpty(T t) {
return MakeFromDefaultValue(std::move(t));
}
template <typename T>
T* MakeFromDefaultValueOrEmpty() {
return MakeFromDefaultValue<T>(EmptyBraces());
}
} // namespace flags_internal
ABSL_NAMESPACE_END
} // namespace absl

60
absl/functional/bind_front.h
View file

@ -11,17 +11,44 @@
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// `absl::bind_front()` returns a functor by binding a number of arguments to
// the front of a provided functor, allowing you to avoid known problems with
// `std::bind()`. It is a form of partial function application
// https://en.wikipedia.org/wiki/Partial_application.
//
// Like `std::bind()` it is implicitly convertible to `std::function`. In
// particular, it may be used as a simpler replacement for `std::bind()` in most
// cases, as it does not require placeholders to be specified. More
// importantly, it provides more reliable correctness guarantees than
// `std::bind()`.
// -----------------------------------------------------------------------------
// File: bind_front.h
// -----------------------------------------------------------------------------
//
// `absl::bind_front()` returns a functor by binding a number of arguments to
// the front of a provided (usually more generic) functor. Unlike `std::bind`,
// it does not require the use of argument placeholders. The simpler syntax of
// `absl::bind_front()` allows you to avoid known misuses with `std::bind()`.
//
// `absl::bind_front()` is meant as a drop-in replacement for C++20's upcoming
// `std::bind_front()`, which similarly resolves these issues with
// `std::bind()`. Both `bind_front()` alternatives, unlike `std::bind()`, allow
// partial function application. (See
// https://en.wikipedia.org/wiki/Partial_application).
#ifndef ABSL_FUNCTIONAL_BIND_FRONT_H_
#define ABSL_FUNCTIONAL_BIND_FRONT_H_
#include "absl/functional/internal/front_binder.h"
#include "absl/utility/utility.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
// bind_front()
//
// Binds the first N arguments of an invocable object and stores them by value,
// except types of `std::reference_wrapper` which are 'unwound' and stored by
// reference.
//
// Like `std::bind()`, `absl::bind_front()` is implicitly convertible to
// `std::function`. In particular, it may be used as a simpler replacement for
// `std::bind()` in most cases, as it does not require placeholders to be
// specified. More importantly, it provides more reliable correctness guarantees
// than `std::bind()`; while `std::bind()` will silently ignore passing more
// parameters than expected, for example, `absl::bind_front()` will report such
// mis-uses as errors.
//
// absl::bind_front(a...) can be seen as storing the results of
// std::make_tuple(a...).
@ -125,19 +152,6 @@
// // dangling references.
// foo->DoInFuture(absl::bind_front(Print, std::ref(hi), "Guest")); // BAD!
// auto f = absl::bind_front(Print, std::ref(hi), "Guest"); // BAD!
#ifndef ABSL_FUNCTIONAL_BIND_FRONT_H_
#define ABSL_FUNCTIONAL_BIND_FRONT_H_
#include "absl/functional/internal/front_binder.h"
#include "absl/utility/utility.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
// Binds the first N arguments of an invocable object and stores them by value,
// except types of std::reference_wrapper which are 'unwound' and stored by
// reference.
template <class F, class... BoundArgs>
constexpr functional_internal::bind_front_t<F, BoundArgs...> bind_front(
F&& func, BoundArgs&&... args) {