1 files changed, 75 insertions, 0 deletions
diff --git a/src/fmt/test/grisu-test.cc b/src/fmt/test/grisu-test.cc
new file mode 100644
index 000000000..3fc670cd4
--- /dev/null
+++ b/src/fmt/test/grisu-test.cc
@@ -0,0 +1,75 @@
+// Formatting library for C++ - Grisu tests
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#include "fmt/format.h"
+#include "gtest.h"
+
+static bool reported_skipped;
+
+#undef TEST
+#define TEST(test_fixture, test_name)        \
+  void test_fixture##test_name();            \
+  GTEST_TEST(test_fixture, test_name) {      \
+    if (FMT_USE_GRISU) {                     \
+      test_fixture##test_name();             \
+    } else if (!reported_skipped) {          \
+      reported_skipped = true;               \
+      fmt::print("Skipping Grisu tests.\n"); \
+    }                                        \
+  }                                          \
+  void test_fixture##test_name()
+
+TEST(GrisuTest, NaN) {
+  auto nan = std::numeric_limits<double>::quiet_NaN();
+  EXPECT_EQ("nan", fmt::format("{}", nan));
+  EXPECT_EQ("-nan", fmt::format("{}", -nan));
+}
+
+TEST(GrisuTest, Inf) {
+  auto inf = std::numeric_limits<double>::infinity();
+  EXPECT_EQ("inf", fmt::format("{}", inf));
+  EXPECT_EQ("-inf", fmt::format("{}", -inf));
+}
+
+TEST(GrisuTest, Zero) { EXPECT_EQ("0.0", fmt::format("{}", 0.0)); }
+
+TEST(GrisuTest, Round) {
+  EXPECT_EQ("1.9156918820264798e-56",
+            fmt::format("{}", 1.9156918820264798e-56));
+  EXPECT_EQ("0.0000", fmt::format("{:.4f}", 7.2809479766055470e-15));
+}
+
+TEST(GrisuTest, Prettify) {
+  EXPECT_EQ("0.0001", fmt::format("{}", 1e-4));
+  EXPECT_EQ("1e-05", fmt::format("{}", 1e-5));
+  EXPECT_EQ("9.999e-05", fmt::format("{}", 9.999e-5));
+  EXPECT_EQ("10000000000.0", fmt::format("{}", 1e10));
+  EXPECT_EQ("100000000000.0", fmt::format("{}", 1e11));
+  EXPECT_EQ("12340000000.0", fmt::format("{}", 1234e7));
+  EXPECT_EQ("12.34", fmt::format("{}", 1234e-2));
+  EXPECT_EQ("0.001234", fmt::format("{}", 1234e-6));
+  EXPECT_EQ("0.1", fmt::format("{}", 0.1f));
+  EXPECT_EQ("0.10000000149011612", fmt::format("{}", double(0.1f)));
+}
+
+TEST(GrisuTest, ZeroPrecision) { EXPECT_EQ("1", fmt::format("{:.0}", 1.0)); }
+
+TEST(GrisuTest, Fallback) {
+  EXPECT_EQ("1e+23", fmt::format("{}", 1e23));
+  EXPECT_EQ("9e-265", fmt::format("{}", 9e-265));
+  EXPECT_EQ("5.423717798060526e+125",
+            fmt::format("{}", 5.423717798060526e+125));
+  EXPECT_EQ("1.372371880954233e-288",
+            fmt::format("{}", 1.372371880954233e-288));
+  EXPECT_EQ("55388492.622190244", fmt::format("{}", 55388492.622190244));
+  EXPECT_EQ("2.2506787569811123e-253",
+            fmt::format("{}", 2.2506787569811123e-253));
+  EXPECT_EQ("1103618912042992.8", fmt::format("{}", 1103618912042992.8));
+  // pow(2, -25) - assymetric boundaries:
+  EXPECT_EQ("2.9802322387695312e-08",
+            fmt::format("{}", 2.9802322387695312e-08));
+}