Always use FMT_STRING internally where possible [Issue #2002] (#2006)

Co-authored-by: Walter Gray <[email protected]>
fmtlib · Nov 15, 2020 · befd7d4 · befd7d4
1 parent f8640d4
commit befd7d4
Show file tree

Hide file tree

Showing 3 changed files with 48 additions and 18 deletions.
diff --git a/include/fmt/chrono.h b/include/fmt/chrono.h
@@ -764,15 +764,24 @@ inline std::chrono::duration<Rep, std::milli> get_milliseconds(
   return std::chrono::duration<Rep, std::milli>(static_cast<Rep>(ms));
 }
 
-template <typename Char, typename Rep, typename OutputIt>
+template <typename Char, typename Rep, typename OutputIt,
+          FMT_ENABLE_IF(std::is_integral<Rep>::value)>
+OutputIt format_duration_value(OutputIt out, Rep val, int) {
+  static FMT_CONSTEXPR_DECL const Char format[] = {'{', '}', 0};
+  return format_to(out, compile_string_to_view(format), val);
+}
+
+template <typename Char, typename Rep, typename OutputIt,
+          FMT_ENABLE_IF(std::is_floating_point<Rep>::value)>
 OutputIt format_duration_value(OutputIt out, Rep val, int precision) {
-  const Char pr_f[] = {'{', ':', '.', '{', '}', 'f', '}', 0};
-  if (precision >= 0) return format_to(out, pr_f, val, precision);
-  const Char fp_f[] = {'{', ':', 'g', '}', 0};
-  const Char format[] = {'{', '}', 0};
-  return format_to(out, std::is_floating_point<Rep>::value ? fp_f : format,
-                   val);
+  static FMT_CONSTEXPR_DECL const Char pr_f[] = {'{', ':', '.', '{',
+                                                 '}', 'f', '}', 0};
+  if (precision >= 0)
+    return format_to(out, compile_string_to_view(pr_f), val, precision);
+  static FMT_CONSTEXPR_DECL const Char fp_f[] = {'{', ':', 'g', '}', 0};
+  return format_to(out, compile_string_to_view(fp_f), val);
 }
+
 template <typename Char, typename OutputIt>
 OutputIt copy_unit(string_view unit, OutputIt out, Char) {
   return std::copy(unit.begin(), unit.end(), out);
@@ -790,10 +799,13 @@ template <typename Char, typename Period, typename OutputIt>
 OutputIt format_duration_unit(OutputIt out) {
   if (const char* unit = get_units<Period>())
     return copy_unit(string_view(unit), out, Char());
-  const Char num_f[] = {'[', '{', '}', ']', 's', 0};
-  if (const_check(Period::den == 1)) return format_to(out, num_f, Period::num);
-  const Char num_def_f[] = {'[', '{', '}', '/', '{', '}', ']', 's', 0};
-  return format_to(out, num_def_f, Period::num, Period::den);
+  static FMT_CONSTEXPR_DECL const Char num_f[] = {'[', '{', '}', ']', 's', 0};
+  if (const_check(Period::den == 1))
+    return format_to(out, compile_string_to_view(num_f), Period::num);
+  static FMT_CONSTEXPR_DECL const Char num_def_f[] = {'[', '{', '}', '/', '{',
+                                                      '}', ']', 's', 0};
+  return format_to(out, compile_string_to_view(num_def_f), Period::num,
+                   Period::den);
 }
 
 template <typename FormatContext, typename OutputIt, typename Rep,

diff --git a/include/fmt/format-inl.h b/include/fmt/format-inl.h
@@ -146,8 +146,8 @@ FMT_FUNC void format_error_code(detail::buffer<char>& out, int error_code,
   error_code_size += detail::to_unsigned(detail::count_digits(abs_value));
   auto it = buffer_appender<char>(out);
   if (message.size() <= inline_buffer_size - error_code_size)
-    format_to(it, "{}{}", message, SEP);
-  format_to(it, "{}{}", ERROR_STR, error_code);
+    format_to(it, FMT_STRING("{}{}"), message, SEP);
+  format_to(it, FMT_STRING("{}{}"), ERROR_STR, error_code);
   assert(out.size() <= inline_buffer_size);
 }
 
@@ -2663,14 +2663,15 @@ template <> struct formatter<detail::bigint> {
     for (auto i = n.bigits_.size(); i > 0; --i) {
       auto value = n.bigits_[i - 1u];
       if (first) {
-        out = format_to(out, "{:x}", value);
+        out = format_to(out, FMT_STRING("{:x}"), value);
         first = false;
         continue;
       }
-      out = format_to(out, "{:08x}", value);
+      out = format_to(out, FMT_STRING("{:08x}"), value);
     }
     if (n.exp_ > 0)
-      out = format_to(out, "p{}", n.exp_ * detail::bigint::bigit_bits);
+      out = format_to(out, FMT_STRING("p{}"),
+                      n.exp_ * detail::bigint::bigit_bits);
     return out;
   }
 };
@@ -2716,8 +2717,8 @@ FMT_FUNC void format_system_error(detail::buffer<char>& out, int error_code,
       int result =
           detail::safe_strerror(error_code, system_message, buf.size());
       if (result == 0) {
-        format_to(detail::buffer_appender<char>(out), "{}: {}", message,
-                  system_message);
+        format_to(detail::buffer_appender<char>(out), FMT_STRING("{}: {}"),
+                  message, system_message);
         return;
       }
       if (result != ERANGE)

diff --git a/test/format-test.cc b/test/format-test.cc
@@ -1805,11 +1805,28 @@ fmt::string_view to_string_view(string_like) { return "foo"; }
 
 constexpr char with_null[3] = {'{', '}', '\0'};
 constexpr char no_null[2] = {'{', '}'};
+static FMT_CONSTEXPR_DECL const char static_with_null[3] = {'{', '}', '\0'};
+static FMT_CONSTEXPR_DECL const wchar_t static_with_null_wide[3] = {'{', '}',
+                                                                    '\0'};
+static FMT_CONSTEXPR_DECL const char static_no_null[2] = {'{', '}'};
+static FMT_CONSTEXPR_DECL const wchar_t static_no_null_wide[2] = {'{', '}'};
 
 TEST(FormatTest, CompileTimeString) {
   EXPECT_EQ("42", fmt::format(FMT_STRING("{}"), 42));
   EXPECT_EQ(L"42", fmt::format(FMT_STRING(L"{}"), 42));
   EXPECT_EQ("foo", fmt::format(FMT_STRING("{}"), string_like()));
+
+  (void)static_with_null;
+  (void)static_with_null_wide;
+  (void)static_no_null;
+  (void)static_no_null_wide;
+#if !defined(_MSC_VER)
+  EXPECT_EQ("42", fmt::format(FMT_STRING(static_with_null), 42));
+  EXPECT_EQ(L"42", fmt::format(FMT_STRING(static_with_null_wide), 42));
+  EXPECT_EQ("42", fmt::format(FMT_STRING(static_no_null), 42));
+  EXPECT_EQ(L"42", fmt::format(FMT_STRING(static_no_null_wide), 42));
+#endif
+
   (void)with_null;
   (void)no_null;
 #if __cplusplus >= 201703L