Forgot to git add so missed a bunch of stuff

libs/format/test/custom-formatter-test.cc

@@ -0,0 +1,68 @@
+/*
+ Custom argument formatter tests
+
+ Copyright (c) 2016, Victor Zverovich
+ All rights reserved.
+
+ For the license information refer to format.h.
+ */
+
+#include "fmt/printf.h"
+#include "gtest-extra.h"
+
+using fmt::BasicPrintfArgFormatter;
+
+// A custom argument formatter that doesn't print `-` for floating-point values
+// rounded to 0.
+class CustomArgFormatter
+  : public fmt::BasicArgFormatter<CustomArgFormatter, char> {
+ public:
+  CustomArgFormatter(fmt::BasicFormatter<char, CustomArgFormatter> &f,
+                     fmt::FormatSpec &s, const char *fmt)
+  : fmt::BasicArgFormatter<CustomArgFormatter, char>(f, s, fmt) {}
+
+  void visit_double(double value) {
+    if (round(value * pow(10, spec().precision())) == 0)
+      value = 0;
+    fmt::BasicArgFormatter<CustomArgFormatter, char>::visit_double(value);
+  }
+};
+
+// A custom argument formatter that doesn't print `-` for floating-point values
+// rounded to 0.
+class CustomPrintfArgFormatter :
+    public BasicPrintfArgFormatter<CustomPrintfArgFormatter, char> {
+ public:
+  typedef BasicPrintfArgFormatter<CustomPrintfArgFormatter, char> Base;
+
+  CustomPrintfArgFormatter(fmt::BasicWriter<char> &w, fmt::FormatSpec &spec)
+  : Base(w, spec) {}
+
+  void visit_double(double value) {
+    if (round(value * pow(10, spec().precision())) == 0)
+      value = 0;
+    Base::visit_double(value);
+  }
+};
+
+std::string custom_format(const char *format_str, fmt::ArgList args) {
+  fmt::MemoryWriter writer;
+  // Pass custom argument formatter as a template arg to BasicFormatter.
+  fmt::BasicFormatter<char, CustomArgFormatter> formatter(args, writer);
+  formatter.format(format_str);
+  return writer.str();
+}
+FMT_VARIADIC(std::string, custom_format, const char *)
+
+std::string custom_sprintf(const char* format_str, fmt::ArgList args){
+  fmt::MemoryWriter writer;
+  fmt::PrintfFormatter<char, CustomPrintfArgFormatter> formatter(args, writer);
+  formatter.format(format_str);
+  return writer.str();
+}
+FMT_VARIADIC(std::string, custom_sprintf, const char*);
+
+TEST(CustomFormatterTest, Format) {
+  EXPECT_EQ("0.00", custom_format("{:.2f}", -.00001));
+  EXPECT_EQ("0.00", custom_sprintf("%.2f", -.00001));
+}