Fix handling of width when formatting int as char

fmtlib · Jan 14, 2021 · f8c2f84 · f8c2f84
1 parent 0fe0b15
commit f8c2f84
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Showing 2 changed files with 14 additions and 13 deletions.
diff --git a/include/fmt/format.h b/include/fmt/format.h
@@ -1592,6 +1592,16 @@ OutputIt write_bytes(OutputIt out, string_view bytes,
   });
 }
 
+template <typename Char, typename OutputIt>
+constexpr OutputIt write_char(OutputIt out, Char value,
+                              const basic_format_specs<Char>& specs) {
+  using iterator = remove_reference_t<decltype(reserve(out, 0))>;
+  return write_padded(out, specs, 1, [=](iterator it) {
+    *it++ = value;
+    return it;
+  });
+}
+
 // Data for write_int that doesn't depend on output iterator type. It is used to
 // avoid template code bloat.
 template <typename Char> struct write_int_data {
@@ -1777,7 +1787,7 @@ template <typename OutputIt, typename Char, typename UInt> struct int_writer {
         [=](iterator it) { return copy_str<Char>(data, data + size, it); });
   }
 
-  void on_chr() { *out++ = static_cast<Char>(abs_value); }
+  void on_chr() { out = write_char(out, static_cast<Char>(abs_value), specs); }
 
   FMT_NORETURN void on_error() {
     FMT_THROW(format_error("invalid type specifier"));
@@ -2043,16 +2053,6 @@ inline OutputIt write(OutputIt out, T value) {
   return write(out, value, basic_format_specs<Char>());
 }
 
-template <typename Char, typename OutputIt>
-constexpr OutputIt write_char(OutputIt out, Char value,
-                              const basic_format_specs<Char>& specs) {
-  using iterator = remove_reference_t<decltype(reserve(out, 0))>;
-  return write_padded(out, specs, 1, [=](iterator it) {
-    *it++ = value;
-    return it;
-  });
-}
-
 template <typename Char, typename OutputIt, typename UIntPtr>
 OutputIt write_ptr(OutputIt out, UIntPtr value,
                    const basic_format_specs<Char>* specs) {

diff --git a/test/format-test.cc b/test/format-test.cc
@@ -868,8 +868,9 @@ TEST(FormatterTest, Width) {
   EXPECT_EQ("    0xcafe", format("{0:10}", reinterpret_cast<void*>(0xcafe)));
   EXPECT_EQ("x          ", format("{0:11}", 'x'));
   EXPECT_EQ("str         ", format("{0:12}", "str"));
-  EXPECT_EQ(fmt::format("{:*^5}", "🤡"), "**🤡**");
-  EXPECT_EQ(fmt::format("{:#6}", 42.0), "  42.0");
+  EXPECT_EQ(format("{:*^5}", "🤡"), "**🤡**");
+  EXPECT_EQ(format("{:#6}", 42.0), "  42.0");
+  EXPECT_EQ(format("{:6c}", static_cast<int>('x')), "x     ");
 }
 
 template <typename T> inline T const_check(T value) { return value; }