Added a test with different implementations for generating background color in SVG.

tests/cpp_tests/svg_renderer_tests/background_color_test.cpp

@@ -0,0 +1,135 @@
+#define BOOST_TEST_MODULE background_color_test
+
+/*
+ * This test module contains several generators for 
+ * the implementation of a background color in SVG
+ * using a rectangle.
+ */
+
+// boost.test
+#include <boost/test/included/unit_test.hpp>
+
+// boost.spirit
+#include <boost/spirit/include/karma.hpp>
+#include <boost/spirit/repository/include/karma_confix.hpp>
+
+// boost
+#include <boost/fusion/tuple.hpp>
+
+// stl
+#include <string>
+#include <sstream>
+
+namespace karma = boost::spirit::karma;
+namespace repository = boost::spirit::repository;
+namespace fusion = boost::fusion;
+using namespace karma;
+
+struct F 
+{
+    F() :
+	x(0),
+	y(0),
+	width(100),
+	height(100),
+	bgcolor("#ffffff"),
+	expected_output("<rect x=\"0\" y=\"0\" width=\"100px\" height=\"100px\" style=\"fill: #ffffff\"/>") {}
+	
+    ~F() {}
+
+    const int x;
+    const int y;
+    const int width;
+    const int height;
+    const std::string bgcolor;
+    const std::string expected_output;
+    std::ostringstream actual_output;
+};
+
+/*
+ * This test case uses one compound generator to generate the SVG element.
+ *
+ * It makes only one call to the format function and uses an ostringstream
+ * as its output destination.
+ *
+ * The attribute values are provided as arguments to the format function.
+ * The disadvantage of this is that the number of arguments is limited
+ * by the preprocessor constant SPIRIT_ARGUMENTS_LIMIT, whose default
+ * value is 10. The advantage is that they can be of any type (as long
+ * as they are compatible with the corresponding generator type).
+ */
+BOOST_FIXTURE_TEST_CASE(bgcolor_stream_test_case, F)
+{
+    actual_output
+	<< format(
+	    "<rect x=\"" << int_ << "\" "
+	    << "y=\"" << int_ << "\" "
+	    << "width=\"" << int_ << string << "\" "
+	    << "height=\"" << int_ << string << "\" "
+	    << "style=\"fill: " << string << "\""
+	    << "/>",
+	    x, y, width, "px", height, "px", bgcolor);
+
+    BOOST_CHECK_EQUAL(actual_output.str(), expected_output);
+}
+
+/*
+ * This test case uses confix to wrap each xml attribute's value
+ * inside double quotes.
+ *
+ * Notice that the generators' attribute list contains also tuples.
+ * Tuples are needed to specify each confix's attributes that contain
+ * more than one generator, like confix()[int_ << string] (this 
+ * generator needs a tuple: tuple<int, string>).
+ *
+ * The difference between this generator and the one in test case
+ * 'bgcolor_stream_test_case' is the use of less << operators and
+ * a more clean handling of double quotes.
+ */
+BOOST_FIXTURE_TEST_CASE(bgcolor_stream_confix_test_case, F)
+{
+    using repository::confix;
+    using fusion::tuple;
+
+    actual_output
+	<< format(
+	    "<rect x=" << confix('"', '"')[int_]
+	    << " y=" << confix('"', '"')[int_]
+	    << " width=" << confix('"', '"')[int_ << string]
+	    << " height=" << confix('"', '"')[int_ << string]
+	    << " style=" << confix('"', '"')["fill: " << string]
+	    << "/>",
+	    x, y, tuple<int, std::string>(width, "px"), tuple<int, std::string>(height, "px"), bgcolor); 
+    
+    BOOST_CHECK_EQUAL(actual_output.str(), expected_output);
+}
+
+/*
+ * This test case generates the angle brackets of the svg/xml tag
+ * using confix. notice that a confix generator can be part of another
+ * confix generator's expression.
+ *
+ * Notice also that the attribute list is the same as in 
+ * 'bgcolor_stream_confix_test_case'. From this one can see that each 
+ * generator is meant to have a list of attributes if it has more than one. 
+ *
+ * If the generator is nested inside another generator, the former's attribute 
+ * list will be another list (a tuple, for example) inside the latter's.
+ */
+BOOST_FIXTURE_TEST_CASE(bgcolor_stream_confix_complete_test_case, F)
+{
+    using repository::confix;
+    using fusion::tuple;
+
+    actual_output
+	<< format(
+	    confix('<', "/>")[
+		"rect x=" << confix('"', '"')[int_]
+		<< " y=" << confix('"', '"')[int_]
+		<< " width=" << confix('"', '"')[int_ << string]
+		<< " height=" << confix('"', '"')[int_ << string]
+		<< " style=" << confix('"', '"')["fill: " << string]],
+		x, y, tuple<int, std::string>(width, "px"), tuple<int, std::string>(height, "px"), bgcolor); 
+    
+    BOOST_CHECK_EQUAL(actual_output.str(), expected_output);
+}