Properly handle escaping in std::exception formatter

fmtlib · Aug 27, 2022 · 1cc09bc · 1cc09bc
1 parent f40db2f
commit 1cc09bc
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Showing 2 changed files with 4 additions and 4 deletions.
diff --git a/include/fmt/std.h b/include/fmt/std.h
@@ -174,13 +174,11 @@ FMT_BEGIN_NAMESPACE
 template <typename Char, typename T>
 struct formatter<T, Char,
                  std::enable_if_t<std::is_base_of_v<std::exception, T>>>
-    : formatter<basic_string_view<Char>> {
+    : formatter<std::string> {
   template <typename FormatContext>
   auto format(const std::exception& ex, FormatContext& ctx) const ->
       typename FormatContext::iterator {
-    auto out = ctx.out();
-    detail::write(out, ex.what());
-    return out;
+    return fmt::formatter<std::string>::format(ex.what(), ctx);
   }
 };
 FMT_END_NAMESPACE

diff --git a/test/std-test.cc b/test/std-test.cc
@@ -84,12 +84,14 @@ TEST(std_test, exception) {
     std::ignore = vec.at(42);
   } catch (const std::exception& ex) {
     EXPECT_EQ(fmt::format("{}", ex), "invalid vector subscript");
+    EXPECT_EQ(fmt::format("{:?}", ex), "\"invalid vector subscript\"");
   }
 
   try {
     std::vector<int> vec;
     std::ignore = vec.at(42);
   } catch (const std::out_of_range& ex) {
     EXPECT_EQ(fmt::format("{}", ex), "invalid vector subscript");
+    EXPECT_EQ(fmt::format("{:?}", ex), "\"invalid vector subscript\"");
   }
 }