rexml: Fix XPath bug of //#{ELEMENT_NAME}[#{POSITION}]

The position should be counted for each nodeset but the previous
implementation counts position for union-ed nodeset.

For example, "/a/*/*[1]" should be matched to "<c1/>" and "<c2/>" with
the following XML.

    <a>
      <b>
        <c1/>
      </b>
      <b>
        <c2/>
      </b>
    </a>

But the previous implementation just returns only "<c1/>".

* lib/rexml/element.rb (REXML::Attributes#each_attribute):
  Support Enumerator for no block use.

* lib/rexml/element.rb (REXML::Attributes#each):
  Support Enumerator for no block use.

* lib/rexml/functions.rb (REXML::Functions.string):
  Support NaN again.

* lib/rexml/xpath_parser.rb: Re-implement "Step" evaluator.
  It should evaluate "AxisSpecifier", "NodeTest" and "Predicate" in one
  step to respect position for each nodeset.

* test/rexml/test_jaxen.rb: Enable more tests. Remained tests should
  be also enabled but it'll not be near future.

* test/rexml/xpath/test_base.rb: Fix expected value.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@63237 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

lib/rexml/element.rb

@@ -1033,6 +1033,7 @@ module REXML
     #    p attr.expanded_name+" => "+attr.value
     #  }
     def each_attribute # :yields: attribute
+      return to_enum(__method__) unless block_given?
       each_value do |val|
         if val.kind_of? Attribute
           yield val
@@ -1048,6 +1049,7 @@ module REXML
     #  doc = Document.new '<a x="1" y="2"/>'
     #  doc.root.attributes.each {|name, value| p name+" => "+value }
     def each
+      return to_enum(__method__) unless block_given?
       each_attribute do |attr|
         yield [attr.expanded_name, attr.value]
       end

lib/rexml/functions.rb

@@ -154,12 +154,16 @@ module REXML
         case object
         when Array
           string(object[0])
-        when Numeric
-          integer = object.to_i
-          if object == integer
-            "%d" % integer
+        when Float
+          if object.nan?
+            "NaN"
           else
-            object.to_s
+            integer = object.to_i
+            if object == integer
+              "%d" % integer
+            else
+              object.to_s
+            end
           end
         when nil
           ""

test/rexml/test_jaxen.rb

@@ -24,14 +24,17 @@ module REXMLTests
     # document() function for XSLT isn't supported
     def _test_message ; process_test_case("message") ; end
     def test_moreover ; process_test_case("moreover") ; end
-    def _test_much_ado ; process_test_case("much_ado") ; end
-    def _test_namespaces ; process_test_case("namespaces") ; end
-    def _test_nitf ; process_test_case("nitf") ; end
+    def test_much_ado ; process_test_case("much_ado") ; end
+    def test_namespaces ; process_test_case("namespaces") ; end
+    def test_nitf ; process_test_case("nitf") ; end
+    # Exception should be considered
     def _test_numbers ; process_test_case("numbers") ; end
     def test_pi ; process_test_case("pi") ; end
     def test_pi2 ; process_test_case("pi2") ; end
     def test_simple ; process_test_case("simple") ; end
+    # TODO: namespace node is needed
     def _test_testNamespaces ; process_test_case("testNamespaces") ; end
+    # document() function for XSLT isn't supported
     def _test_text ; process_test_case("text") ; end
     def test_underscore ; process_test_case("underscore") ; end
     def _test_web ; process_test_case("web") ; end

test/rexml/xpath/test_base.rb

@@ -713,7 +713,7 @@ module REXMLTests
       XML
       d = REXML::Document.new( source )
       r = REXML::XPath.match( d, %q{/a/*/*[1]} )
-      assert_equal(["1"],
+      assert_equal(["1", "3"],
                    r.collect {|element| element.attribute("id").value})
     end
 
@@ -849,7 +849,7 @@ module REXMLTests
       EOL
       d = REXML::Document.new( string )
       cs = XPath.match( d, '/a/*/*[1]' )
-      assert_equal(["c1"], cs.collect(&:name))
+      assert_equal(["c1", "c2"], cs.collect(&:name))
     end
 
     def test_sum