deprecate _format UDL in code using FMT_DEPRECATED

fmtlib · Dec 11, 2021 · fe302bf · fe302bf
1 parent 3a951a6
commit fe302bf
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Showing 4 changed files with 46 additions and 10 deletions.
diff --git a/include/fmt/format.h b/include/fmt/format.h
@@ -3056,7 +3056,7 @@ constexpr auto operator"" _a(const char* s, size_t) -> detail::udl_arg<char> {
     using namespace fmt::literals;
     std::string message = "The answer is {}"_format(42);
  */
-constexpr auto operator"" _format(const char* s, size_t n)
+FMT_DEPRECATED constexpr auto operator"" _format(const char* s, size_t n)
     -> detail::udl_formatter<char> {
   return {{s, n}};
 }

diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
@@ -41,7 +41,7 @@ endfunction()
 # Adds a test.
 # Usage: add_fmt_test(name srcs...)
 function(add_fmt_test name)
-  cmake_parse_arguments(ADD_FMT_TEST "HEADER_ONLY;MODULE" "" "" ${ARGN})
+  cmake_parse_arguments(ADD_FMT_TEST "HEADER_ONLY;MODULE;DEPRECATED" "" "" ${ARGN})
 
   set(sources ${name}.cc ${ADD_FMT_TEST_UNPARSED_ARGUMENTS})
   if (ADD_FMT_TEST_HEADER_ONLY)
@@ -63,7 +63,7 @@ function(add_fmt_test name)
   if (FMT_PEDANTIC)
     target_compile_options(${name} PRIVATE ${PEDANTIC_COMPILE_FLAGS})
   endif ()
-  if (FMT_WERROR)
+  if (FMT_WERROR AND NOT ADD_FMT_TEST_DEPRECATED)
     target_compile_options(${name} PRIVATE ${WERROR_FLAG})
   endif ()
   add_test(NAME ${name} COMMAND ${name})
@@ -79,6 +79,7 @@ add_fmt_test(format-test mock-allocator.h)
 if (MSVC)
   target_compile_options(format-test PRIVATE /bigobj)
 endif ()
+add_fmt_test(format-test-deprecated DEPRECATED)
 if (NOT (MSVC AND BUILD_SHARED_LIBS))
   add_fmt_test(format-impl-test HEADER_ONLY header-only-test.cc)
 endif ()

diff --git a/test/format-test-deprecated.cc b/test/format-test-deprecated.cc
@@ -0,0 +1,42 @@
+// Formatting library for C++ - formatting library tests
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+// clang-format off
+#include "fmt/format.h"
+// clang-format on
+
+#include "gmock/gmock.h"
+#include "util.h"
+
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<date> {
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    auto it = ctx.begin();
+    if (it != ctx.end() && *it == 'd') ++it;
+    return it;
+  }
+
+  auto format(const date& d, format_context& ctx) -> decltype(ctx.out()) {
+    format_to(ctx.out(), "{}-{}-{}", d.year(), d.month(), d.day());
+    return ctx.out();
+  }
+};
+FMT_END_NAMESPACE
+
+#if FMT_USE_USER_DEFINED_LITERALS
+
+using namespace fmt::literals;
+
+TEST(format_test, format_udl) {
+  EXPECT_EQ("{}c{}"_format("ab", 1), fmt::format("{}c{}", "ab", 1));
+  EXPECT_EQ("foo"_format(), "foo");
+  EXPECT_EQ("{0:10}"_format(42), "        42");
+  EXPECT_EQ("{}"_format(date(2015, 10, 21)), "2015-10-21");
+}
+#endif  // FMT_USE_USER_DEFINED_LITERALS
+
diff --git a/test/format-test.cc b/test/format-test.cc
@@ -1761,13 +1761,6 @@ TEST(format_test, custom_format_compile_time_string) {
 
 using namespace fmt::literals;
 
-TEST(format_test, format_udl) {
-  EXPECT_EQ("{}c{}"_format("ab", 1), fmt::format("{}c{}", "ab", 1));
-  EXPECT_EQ("foo"_format(), "foo");
-  EXPECT_EQ("{0:10}"_format(42), "        42");
-  EXPECT_EQ("{}"_format(date(2015, 10, 21)), "2015-10-21");
-}
-
 TEST(format_test, named_arg_udl) {
   auto udl_a = fmt::format("{first}{second}{first}{third}", "first"_a = "abra",
                            "second"_a = "cad", "third"_a = 99);