improve the XML generation: prolog optional, using [] instead of :empty

lib/saxy.ex

@@ -83,7 +83,7 @@ defmodule Saxy do
       iex> import Saxy.XML
       iex> element = element("person", [gender: "female"], "Alice")
       {"person", [{"gender", "female"}], [{:characters, "Alice"}]}
-      iex> Saxy.encode!(element, [])
+      iex> Saxy.encode!(element, [version: "1.0"])
       "<?xml version=\"1.0\"?><person gender=\"female\">Alice</person>"
 
   See `Saxy.XML` for more XML building APIs.
@@ -100,7 +100,7 @@ defmodule Saxy do
       iex> john = %Person{gender: :male, name: "John"}
       iex> import Saxy.XML
       iex> root = element("people", [], [jack, john])
-      iex> Saxy.encode!(root, [])
+      iex> Saxy.encode!(root, [version: "1.0"])
       "<?xml version=\"1.0\"?><people><person gender=\"male\">Jack</person><person gender=\"male\">John</person></people>"
 
   """

lib/saxy/encoder.ex

@@ -1,13 +1,45 @@
 defmodule Saxy.Encoder do
   @moduledoc false
 
+  @doc """
+  Encode data into a iodata list (merge between list and binary data).
+
+  Example:
+    iex> Saxy.Encoder.encode_to_iodata({"foo", [], []})
+    [[[60, "foo"], 47, 62]]
+
+    iex> Saxy.Encoder.encode_to_iodata({"foo", [{"id", "10"}], []})
+    [[[60, "foo", 32, "id", 61, 34, "10", 34], 47, 62]]
+  """
+  def encode_to_iodata(root, prolog \\ nil)
+
+  def encode_to_iodata(root, nil) do
+    [element(root)]
+  end
+
   def encode_to_iodata(root, prolog) do
     prolog = prolog(prolog)
     element = element(root)
 
     [prolog | element]
   end
 
+  @doc """
+  Encode data into a XML string representation.
+
+  Example:
+    iex> Saxy.Encoder.encode_to_binary({"foo", [], []})
+    "<foo/>"
+
+    iex> Saxy.Encoder.encode_to_binary({"foo", [{"id", "10"}], []})
+    "<foo id=\\"10\\"/>"
+  """
+  def encode_to_binary(root, prolog \\ nil) do
+    root
+    |> encode_to_iodata(prolog)
+    |> IO.iodata_to_binary()
+  end
+
   defp prolog(%Saxy.Prolog{} = prolog) do
     ['<?xml', version(prolog.version), encoding(prolog.encoding), standalone(prolog.standalone), '?>']
   end
@@ -34,7 +66,7 @@ defmodule Saxy.Encoder do
     [?\s, 'standalone', ?=, ?", "yes", ?"]
   end
 
-  defp element({tag_name, attributes, :empty}) do
+  defp element({tag_name, attributes, []}) do
     [start_tag(tag_name, attributes), ?/, ?>]
   end
 

lib/saxy/xml.ex

@@ -54,7 +54,7 @@ defmodule Saxy.XML do
     {
       to_string(name),
       attributes(attributes),
-      :empty
+      []
     }
   end
 

mix.lock

@@ -1,8 +1,8 @@
 %{
-  "earmark": {:hex, :earmark, "1.2.5", "4d21980d5d2862a2e13ec3c49ad9ad783ffc7ca5769cf6ff891a4553fbaae761", [:mix], [], "hexpm"},
-  "ex_doc": {:hex, :ex_doc, "0.19.1", "519bb9c19526ca51d326c060cb1778d4a9056b190086a8c6c115828eaccea6cf", [:mix], [{:earmark, "~> 1.1", [hex: :earmark, repo: "hexpm", optional: false]}, {:makeup_elixir, "~> 0.7", [hex: :makeup_elixir, repo: "hexpm", optional: false]}], "hexpm"},
-  "makeup": {:hex, :makeup, "0.5.1", "966c5c2296da272d42f1de178c1d135e432662eca795d6dc12e5e8787514edf7", [:mix], [{:nimble_parsec, "~> 0.2.2", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm"},
-  "makeup_elixir": {:hex, :makeup_elixir, "0.8.0", "1204a2f5b4f181775a0e456154830524cf2207cf4f9112215c05e0b76e4eca8b", [:mix], [{:makeup, "~> 0.5.0", [hex: :makeup, repo: "hexpm", optional: false]}, {:nimble_parsec, "~> 0.2.2", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm"},
-  "nimble_parsec": {:hex, :nimble_parsec, "0.2.2", "d526b23bdceb04c7ad15b33c57c4526bf5f50aaa70c7c141b4b4624555c68259", [:mix], [], "hexpm"},
-  "stream_data": {:hex, :stream_data, "0.4.2", "fa86b78c88ec4eaa482c0891350fcc23f19a79059a687760ddcf8680aac2799b", [:mix], [], "hexpm"},
+  "earmark": {:hex, :earmark, "1.2.5", "4d21980d5d2862a2e13ec3c49ad9ad783ffc7ca5769cf6ff891a4553fbaae761", [:mix], [], "hexpm", "c57508ddad47dfb8038ca6de1e616e66e9b87313220ac5d9817bc4a4dc2257b9"},
+  "ex_doc": {:hex, :ex_doc, "0.19.1", "519bb9c19526ca51d326c060cb1778d4a9056b190086a8c6c115828eaccea6cf", [:mix], [{:earmark, "~> 1.1", [hex: :earmark, repo: "hexpm", optional: false]}, {:makeup_elixir, "~> 0.7", [hex: :makeup_elixir, repo: "hexpm", optional: false]}], "hexpm", "dc87f778d8260da0189a622f62790f6202af72f2f3dee6e78d91a18dd2fcd137"},
+  "makeup": {:hex, :makeup, "0.5.1", "966c5c2296da272d42f1de178c1d135e432662eca795d6dc12e5e8787514edf7", [:mix], [{:nimble_parsec, "~> 0.2.2", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "259748a45dfcf5f49765a7c29c9594791c82de23e22d7a3e6e59533fe8e8935b"},
+  "makeup_elixir": {:hex, :makeup_elixir, "0.8.0", "1204a2f5b4f181775a0e456154830524cf2207cf4f9112215c05e0b76e4eca8b", [:mix], [{:makeup, "~> 0.5.0", [hex: :makeup, repo: "hexpm", optional: false]}, {:nimble_parsec, "~> 0.2.2", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "393d17c5a648e3b30522b2a4743bd1dc3533e1227c8c2823ebe8c3a8e5be5913"},
+  "nimble_parsec": {:hex, :nimble_parsec, "0.2.2", "d526b23bdceb04c7ad15b33c57c4526bf5f50aaa70c7c141b4b4624555c68259", [:mix], [], "hexpm", "4ababf5c44164f161872704e1cfbecab3935fdebec66c72905abaad0e6e5cef6"},
+  "stream_data": {:hex, :stream_data, "0.4.2", "fa86b78c88ec4eaa482c0891350fcc23f19a79059a687760ddcf8680aac2799b", [:mix], [], "hexpm", "54d6bf6f1e5e27fbf4a7784a2bffbb993446d0efd079debca0f27bf859c0d1cf"},
 }

test/saxy/encoder_test.exs

@@ -5,10 +5,10 @@ defmodule Saxy.EncoderTest do
     document = {
       "person",
       [{"first_name", "John"}, {"last_name", "Doe"}],
-      :empty
+      []
     }
 
-    xml = encode(document)
+    xml = encode(document, version: "1.0")
 
     assert xml == ~s(<?xml version="1.0"?><person first_name="John" last_name="Doe"/>)
   end
@@ -22,22 +22,22 @@ defmodule Saxy.EncoderTest do
       content
     }
 
-    xml = encode(document)
+    xml = encode(document, version: "1.0")
 
     assert xml == ~s(<?xml version="1.0"?><person first_name="John" last_name="Doe">Hello my name is John Doe</person>)
   end
 
   test "encodes attributes with escapable characters" do
     xml = encode({"person", [{"first_name", "&'\"<>"}], []})
 
-    assert xml == ~s(<?xml version="1.0"?><person first_name="&amp;&apos;&quot;&lt;&gt;"></person>)
+    assert xml == ~s(<person first_name="&amp;&apos;&quot;&lt;&gt;"/>)
   end
 
   test "encodes CDATA" do
     children = [{:cdata, "Tom & Jerry"}]
 
     document = {"person", [], children}
-    xml = encode(document)
+    xml = encode(document, version: "1.0")
 
     assert xml == ~s(<?xml version="1.0"?><person><![CDATA[Tom & Jerry]]></person>)
   end
@@ -48,7 +48,7 @@ defmodule Saxy.EncoderTest do
     ]
 
     document = {"movie", [], content}
-    xml = encode(document)
+    xml = encode(document, version: "1.0")
 
     assert xml == ~s(<?xml version="1.0"?><movie>Tom &amp; Jerry</movie>)
   end
@@ -61,7 +61,7 @@ defmodule Saxy.EncoderTest do
     ]
 
     document = {"movie", [], content}
-    xml = encode(document)
+    xml = encode(document, [])
 
     assert xml == ~s(<?xml version="1.0"?><movie>&foo;&x3C;&x60;</movie>)
   end
@@ -75,7 +75,7 @@ defmodule Saxy.EncoderTest do
     document = {"movie", [], content}
     xml = encode(document)
 
-    assert xml == ~s(<?xml version="1.0"?><movie><!--This is obviously a comment--><!--A+, A, A- --></movie>)
+    assert xml == ~s(<movie><!--This is obviously a comment--><!--A+, A, A- --></movie>)
   end
 
   test "encodes processing instruction" do
@@ -84,22 +84,22 @@ defmodule Saxy.EncoderTest do
     ]
 
     document = {"movie", [], content}
-    xml = encode(document)
+    xml = encode(document, version: "1.0")
 
     assert xml == ~s(<?xml version="1.0"?><movie><?xml-stylesheet type="text/xsl" href="style.xsl"?></movie>)
   end
 
   test "encodes nested element" do
     children = [
-      {"address", [{"street", "foo"}, {"city", "bar"}], :empty},
+      {"address", [{"street", "foo"}, {"city", "bar"}], []},
       {"gender", [], [{:characters, "male"}]}
     ]
 
     document = {"person", [{"first_name", "John"}, {"last_name", "Doe"}], children}
     xml = encode(document)
 
     assert xml ==
-             ~s(<?xml version="1.0"?><person first_name="John" last_name="Doe"><address street="foo" city="bar"/><gender>male</gender></person>)
+             ~s(<person first_name="John" last_name="Doe"><address street="foo" city="bar"/><gender>male</gender></person>)
   end
 
   test "integration with builder" do
@@ -120,7 +120,7 @@ defmodule Saxy.EncoderTest do
     xml =
       :rss
       |> element([version: "2.0"], items)
-      |> encode([])
+      |> encode(version: "1.0")
 
     expected = """
     <?xml version="1.0"?>
@@ -158,10 +158,10 @@ defmodule Saxy.EncoderTest do
 
     xml = "<?xml version=\"1.0\"?>" <> xml
 
-    assert encode(document) == xml
+    assert encode(document, version: "1.0") == xml
   end
 
-  defp encode(document, prolog \\ []) do
+  defp encode(document, prolog \\ nil) do
     document
     |> Saxy.Encoder.encode_to_iodata(prolog)
     |> IO.iodata_to_binary()

test/saxy/xml_test.exs

@@ -15,11 +15,11 @@ defmodule Saxy.XMLTest do
 
   describe "empty_element/2" do
     test "generates empty element in simple form" do
-      assert empty_element("foo", []) == {"foo", [], :empty}
-      assert empty_element(:foo, []) == {"foo", [], :empty}
+      assert empty_element("foo", []) == {"foo", [], []}
+      assert empty_element(:foo, []) == {"foo", [], []}
 
-      assert empty_element("foo", a: 1) == {"foo", [{"a", "1"}], :empty}
-      assert empty_element("foo", %{"a" => 1}) == {"foo", [{"a", "1"}], :empty}
+      assert empty_element("foo", a: 1) == {"foo", [{"a", "1"}], []}
+      assert empty_element("foo", %{"a" => 1}) == {"foo", [{"a", "1"}], []}
     end
   end
 

test/saxy_test.exs

@@ -12,6 +12,7 @@ defmodule SaxyTest do
   }
 
   doctest Saxy
+  doctest Saxy.Encoder
 
   test "parse_string/3 parses a XML document binary" do
     data = File.read!("./test/support/fixture/food.xml")
@@ -272,7 +273,7 @@ defmodule SaxyTest do
 
     test "encodes XML document into string" do
       root = element("foo", [], "foo")
-      assert Saxy.encode!(root) == ~s(<?xml version="1.0"?><foo>foo</foo>)
+      assert Saxy.encode!(root, version: "1.0") == ~s(<?xml version="1.0"?><foo>foo</foo>)
     end
   end
 
@@ -281,7 +282,7 @@ defmodule SaxyTest do
 
     test "encodes XML document into IO data" do
       root = element("foo", [], "foo")
-      assert xml = Saxy.encode_to_iodata!(root)
+      assert xml = Saxy.encode_to_iodata!(root, version: "1.0")
       assert is_list(xml)
       assert IO.iodata_to_binary(xml) == ~s(<?xml version="1.0"?><foo>foo</foo>)
     end