tests: Add tests for fp roundtrip

We test min/max and several different mantissas for the entire exponent range
for both float and double.

It's not clear whether all supported compilers provide an implementation of
sprintf/strtod that supports roundtripping so we may need to disable some of
these tests in the future.

1 files changed, 73 insertions, 11 deletions

diff --git a/tests/test_dom_modify.cpp b/tests/test_dom_modify.cpp
index 70cba53..1fb9dd3 100644
--- a/tests/test_dom_modify.cpp
+++ b/tests/test_dom_modify.cpp
@@ -2,6 +2,7 @@
 
 #include <limits>
 #include <string>
+#include <cmath>
 
 TEST_XML(dom_attr_assign, "<node/>")
 {
@@ -99,6 +100,17 @@ TEST_XML(dom_attr_set_value_llong, "<node/>")
 }
 #endif
 
+TEST_XML(dom_attr_assign_large_number, "<node attr1='' attr2='' />")
+{
+	xml_node node = doc.child(STR("node"));
+
+	node.attribute(STR("attr1")) = std::numeric_limits<float>::max();
+	node.attribute(STR("attr2")) = std::numeric_limits<double>::max();
+
+	CHECK(test_node(node, STR("<node attr1=\"3.40282347e+038\" attr2=\"1.7976931348623157e+308\" />"), STR(""), pugi::format_raw) ||
+		  test_node(node, STR("<node attr1=\"3.40282347e+38\" attr2=\"1.7976931348623157e+308\" />"), STR(""), pugi::format_raw));
+}
+
 TEST_XML(dom_node_set_name, "<node>text</node>")
 {
 	CHECK(doc.child(STR("node")).set_name(STR("n")));
@@ -752,17 +764,6 @@ TEST_XML_FLAGS(dom_node_copy_types, "<?xml version='1.0'?><!DOCTYPE id><root><?p
 	CHECK_NODE(doc, STR("<?xml version=\"1.0\"?><!DOCTYPE id><?xml version=\"1.0\"?><!DOCTYPE id><root><?pi value?><!--comment--><node id=\"1\">pcdata<![CDATA[cdata]]></node></root><root><?pi value?><!--comment--><node id=\"1\">pcdata<![CDATA[cdata]]></node></root>"));
 }
 
-TEST_XML(dom_attr_assign_large_number, "<node attr1='' attr2='' />")
-{
-	xml_node node = doc.child(STR("node"));
-
-	node.attribute(STR("attr1")) = std::numeric_limits<float>::max();
-	node.attribute(STR("attr2")) = std::numeric_limits<double>::max();
-
-	CHECK(test_node(node, STR("<node attr1=\"3.40282347e+038\" attr2=\"1.7976931348623157e+308\" />"), STR(""), pugi::format_raw) ||
-		  test_node(node, STR("<node attr1=\"3.40282347e+38\" attr2=\"1.7976931348623157e+308\" />"), STR(""), pugi::format_raw));
-}
-
 TEST(dom_node_declaration_name)
 {
 	xml_document doc;
@@ -1444,3 +1445,64 @@ TEST(dom_node_copy_declaration_empty_name)
 
 	CHECK_STRING(decl2.name(), STR(""));
 }
+
+TEST(dom_fp_roundtrip_min_max)
+{
+	xml_document doc;
+	xml_node node = doc.append_child(STR("node"));
+	xml_attribute attr = node.append_attribute(STR("attr"));
+
+	node.text().set(std::numeric_limits<float>::min());
+	CHECK(node.text().as_float() == std::numeric_limits<float>::min());
+
+	attr.set_value(std::numeric_limits<float>::max());
+	CHECK(attr.as_float() == std::numeric_limits<float>::max());
+
+	attr.set_value(std::numeric_limits<double>::min());
+	CHECK(attr.as_double() == std::numeric_limits<double>::min());
+
+	node.text().set(std::numeric_limits<double>::max());
+	CHECK(node.text().as_double() == std::numeric_limits<double>::max());
+}
+
+const double fp_roundtrip_base[] =
+{
+	0.31830988618379067154,
+	0.43429448190325182765,
+	0.57721566490153286061,
+	0.69314718055994530942,
+	0.70710678118654752440,
+	0.78539816339744830962,
+};
+
+TEST(dom_fp_roundtrip_float)
+{
+	xml_document doc;
+
+	for (int e = -125; e <= 128; ++e)
+	{
+		for (size_t i = 0; i < sizeof(fp_roundtrip_base) / sizeof(fp_roundtrip_base[0]); ++i)
+		{
+			float value = ldexpf(fp_roundtrip_base[i], e);
+
+			doc.text().set(value);
+			CHECK(doc.text().as_float() == value);
+		}
+	}
+}
+
+TEST(dom_fp_roundtrip_double)
+{
+	xml_document doc;
+
+	for (int e = -1021; e <= 1024; ++e)
+	{
+		for (size_t i = 0; i < sizeof(fp_roundtrip_base) / sizeof(fp_roundtrip_base[0]); ++i)
+		{
+			double value = ldexp(fp_roundtrip_base[i], e);
+
+			doc.text().set(value);
+			CHECK(doc.text().as_double() == value);
+		}
+	}
+}