From 395cf0f03ecaa35c24faaaca42d481e316f00422 Mon Sep 17 00:00:00 2001
From: Victor Zverovich <viz@fb.com>
Date: Tue, 12 Apr 2022 06:45:46 -0700
Subject: [PATCH] Fix detection of unformattable pointers

---
 include/fmt/core.h |  1 +
 test/core-test.cc  | 12 ++++++++++++
 2 files changed, 13 insertions(+)

diff --git a/include/fmt/core.h b/include/fmt/core.h
index d8aa4deb..36c92f66 100644
--- a/include/fmt/core.h
+++ b/include/fmt/core.h
@@ -1478,6 +1478,7 @@ template <typename Context> struct arg_mapper {
   template <typename T, typename U = remove_cvref_t<T>,
             FMT_ENABLE_IF(!is_string<U>::value && !is_char<U>::value &&
                           !std::is_array<U>::value &&
+                          !std::is_pointer<U>::value &&
                           !has_format_as<U>::value &&
                           (has_formatter<U, Context>::value ||
                            has_fallback_formatter<U, char_type>::value))>
diff --git a/test/core-test.cc b/test/core-test.cc
index a040d241..8692c76b 100644
--- a/test/core-test.cc
+++ b/test/core-test.cc
@@ -679,6 +679,7 @@ TEST(format_test, constexpr_parse_format_string) {
 #endif  // FMT_USE_CONSTEXPR
 
 struct enabled_formatter {};
+struct enabled_ptr_formatter {};
 struct disabled_formatter {};
 struct disabled_formatter_convertible {
   operator int() const { return 42; }
@@ -693,6 +694,16 @@ template <> struct formatter<enabled_formatter> {
     return ctx.out();
   }
 };
+
+template <> struct formatter<enabled_ptr_formatter*> {
+  auto parse(format_parse_context& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+  auto format(enabled_ptr_formatter*, format_context& ctx)
+      -> decltype(ctx.out()) {
+    return ctx.out();
+  }
+};
 FMT_END_NAMESPACE
 
 TEST(core_test, has_formatter) {
@@ -785,6 +796,7 @@ TEST(core_test, is_formattable) {
   static_assert(!fmt::is_formattable<fmt::basic_string_view<wchar_t>>::value,
                 "");
   static_assert(fmt::is_formattable<enabled_formatter>::value, "");
+  static_assert(!fmt::is_formattable<enabled_ptr_formatter*>::value, "");
   static_assert(!fmt::is_formattable<disabled_formatter>::value, "");
   static_assert(fmt::is_formattable<disabled_formatter_convertible>::value, "");