Add a spec for formatting non-VALUEs as pointers in rb_sprintf.

Author: aardvark179

optional/capi/ext/string_spec.c

@@ -488,6 +488,15 @@ static VALUE string_spec_rb_sprintf7(VALUE self, VALUE str, VALUE obj) {
   return results;
 }
 
+static VALUE string_spec_rb_sprintf8(VALUE self, VALUE str, VALUE num) {
+  VALUE results = rb_ary_new();
+  rb_ary_push(results, rb_sprintf(RSTRING_PTR(str), FIX2LONG(num)));
+  char cstr[256];
+  int len = snprintf(cstr, 256, RSTRING_PTR(str), FIX2LONG(num));
+  rb_ary_push(results, rb_str_new(cstr, len));
+  return results;
+}
+
 PRINTF_ARGS(static VALUE string_spec_rb_vsprintf_worker(char* fmt, ...), 1, 2);
 static VALUE string_spec_rb_vsprintf_worker(char* fmt, ...) {
   va_list varargs;
@@ -648,6 +657,7 @@ void Init_string_spec(void) {
   rb_define_method(cls, "rb_sprintf5", string_spec_rb_sprintf5, 3);
   rb_define_method(cls, "rb_sprintf6", string_spec_rb_sprintf6, 3);
   rb_define_method(cls, "rb_sprintf7", string_spec_rb_sprintf7, 2);
+  rb_define_method(cls, "rb_sprintf8", string_spec_rb_sprintf8, 2);
   rb_define_method(cls, "rb_vsprintf", string_spec_rb_vsprintf, 4);
   rb_define_method(cls, "rb_str_equal", string_spec_rb_str_equal, 2);
   rb_define_method(cls, "rb_usascii_str_new", string_spec_rb_usascii_str_new, 2);

optional/capi/string_spec.rb

@@ -1095,6 +1095,11 @@ def inspect
       res = @s.rb_sprintf7("%p", "Hello")
       res[0].should == res[1]
     end
+
+    it "can format a raw number a pointer and gives the same output as sprintf in C" do
+      res = @s.rb_sprintf7("%p", 0x223643);
+      res[0].should == res[1]
+    end
   end
 
   describe "rb_vsprintf" do