Add basic support for properties

.travis.yml

@@ -1,5 +1,6 @@
 language: elixir
-elixir: '1.5.2'
+elixir: '1.8.1'
+otp_release: '21.3'
 script:
 - "mix test --trace"
-- "mix dialyzer"
+- "mix dialyzer"

lib/org/document.ex

@@ -102,6 +102,22 @@ defmodule Org.Document do
     %Org.Document{doc | sections: [Org.Section.prepend_content(current_section, content) | rest]}
   end
 
+
+  @doc ~S"""
+  Prepend property to the currently deepest section.
+
+  While preserving order is usually not needed for parsing and
+  interpreting properties, order is still preserved here to e.g. allow
+  re-serialization that preserves line order. This would be desirable
+  e.g. since version control is often based on lines, and works better
+  if there is less noise in the commit history.
+
+  See prepend_content for usage.
+  """
+  def prepend_property(%Org.Document{sections: [current_section | rest]} = doc, property) do
+    %Org.Document{doc | sections: [Org.Section.prepend_property(current_section, property) | rest]}
+  end
+
   @doc ~S"""
   Update the last prepended content. Yields the content to the given updater.
 

lib/org/lexer.ex

@@ -11,7 +11,7 @@ defmodule Org.Lexer do
 
   @type t :: %Org.Lexer{
     tokens: list(token),
-    mode: :normal | :raw
+    mode: :normal | :raw | :property
   }
 
   @moduledoc ~S"""
@@ -58,6 +58,9 @@ defmodule Org.Lexer do
   @section_title_re ~r/^(\*+) (.+)$/
   @empty_line_re    ~r/^\s*$/
   @table_row_re     ~r/^\s*(?:\|[^|]*)+\|\s*$/
+  @begin_props_re   ~r/^\s*\:PROPERTIES\:$/
+  @property_re      ~r/^\s*\:([A-Za-z]+)\:\s*(.+)$/
+  @end_drawer_re    ~r/^\s*\:END\:$/
 
   defp lex_line(line, %Org.Lexer{mode: :normal} = lexer) do
     cond do
@@ -78,6 +81,8 @@ defmodule Org.Lexer do
         |> List.flatten
         |> Enum.map(&String.trim/1)
         append_token(lexer, {:table_row, cells})
+      Regex.run(@begin_props_re, line) ->
+        append_token(lexer, {:begin_drawer, "PROPERTIES"}) |> set_mode(:property)
       true ->
         append_token(lexer, {:text, line})
     end
@@ -91,6 +96,16 @@ defmodule Org.Lexer do
     end
   end
 
+  defp lex_line(line, %Org.Lexer{mode: :property} = lexer) do
+    cond do
+      Regex.run(@end_drawer_re, line) ->
+        append_token(lexer, {:end_drawer}) |> set_mode(:normal)
+      match = Regex.run(@property_re, line) ->
+        [_, key, value] = match
+        append_token(lexer, {:property, key, value})
+    end
+  end
+
   defp append_token(%Org.Lexer{} = lexer, token) do
     %Org.Lexer{lexer | tokens: [token | lexer.tokens]}
   end

lib/org/parser.ex

@@ -3,7 +3,7 @@ defmodule Org.Parser do
 
   @type t :: %Org.Parser{
     doc: Org.Document.t,
-    mode: :paragraph | :table | :code_block | nil,
+    mode: :paragraph | :properties | :table | :code_block | nil,
   }
 
   @moduledoc ~S"""
@@ -88,4 +88,18 @@ defmodule Org.Parser do
   defp parse_token({:end_src}, %Org.Parser{mode: :code_block} = parser) do
     %Org.Parser{parser | mode: nil}
   end
+
+  defp parse_token({:begin_drawer, "PROPERTIES"}, parser) do
+    %Org.Parser{parser | mode: :properties}
+  end
+
+  defp parse_token({:property, key, value}, %Org.Parser{mode: :properties} = parser) do
+    doc = Org.Document.prepend_property(parser.doc, {key |> String.to_atom(), value})
+
+    %Org.Parser{parser | doc: doc}
+  end
+
+  defp parse_token({:end_drawer}, %Org.Parser{mode: :properties} = parser) do
+    %Org.Parser{parser | mode: nil}
+  end
 end

lib/org/section.ex

@@ -1,11 +1,11 @@
 defmodule Org.Section do
-  defstruct title: "", children: [], contents: []
+  defstruct title: "", children: [], contents: [], properties: []
 
   @moduledoc ~S"""
   Represents a section of a document with a title and possible contents & subsections.
 
   Example:
-      iex> source = "* Hello\nWorld\n** What's up?\nNothing much.\n** How's it going?\nAll fine, whow are you?\n"
+      iex> source = "* Hello\nWorld\n** What's up?\n   :PROPERTIES:\n   :Register: non-formal\n   :Intent: inquisitive\n   :END:\nNothing much.\n** How's it going?\nAll fine, whow are you?\n"
       iex> doc = Org.Parser.parse(source)
       iex> section = Org.section(doc, ["Hello"])
       iex> section.contents
@@ -14,12 +14,16 @@ defmodule Org.Section do
       2
       iex> for child <- section.children, do: child.title
       ["What's up?", "How's it going?"]
+      iex> subsection_with_props = Org.section(doc, ["Hello", "What's up?"])
+      iex> subsection_with_props.properties
+      [Register: "non-formal", Intent: "inquisitive"]
   """
 
   @type t :: %Org.Section{
     title: String.t,
     children: list(Org.Section.t),
     contents: list(Org.Content.t),
+    properties: list(Keyword.t),
   }
 
   def add_nested(parent, 1, child) do
@@ -39,6 +43,7 @@ defmodule Org.Section do
       section |
       children: Enum.reverse(Enum.map(section.children, &reverse_recursive/1)),
       contents: Enum.reverse(Enum.map(section.contents, &Org.Content.reverse_recursive/1)),
+      properties: Enum.reverse(section.properties),
     }
   end
 
@@ -82,4 +87,13 @@ defmodule Org.Section do
   def update_content(%Org.Section{children: [current_section | rest]} = section, updater) do
     %Org.Section{section | children: [update_content(current_section, updater) | rest]}
   end
+
+  @doc "Adds property to the last prepended section"
+  def prepend_property(%Org.Section{children: []} = section, property) do
+    %Org.Section{section | properties: [property | section.properties]}
+  end
+
+  def prepend_property(%Org.Section{children: [current_child | children]} = section, property) do
+    %Org.Section{section | children: [prepend_property(current_child, property) | children]}
+  end
 end

mix.exs

@@ -35,8 +35,8 @@ defmodule Org.Mixfile do
     [
       # {:dep_from_hexpm, "~> 0.3.0"},
       # {:dep_from_git, git: "https://github.com/elixir-lang/my_dep.git", tag: "0.1.0"},
-      {:ex_doc, "~> 0.16", only: :dev, runtime: false},
-      {:dialyxir, "~> 0.5.1"}
+      {:ex_doc, "~> 0.19", only: :dev, runtime: false},
+      {:dialyxir, "~> 1.0.0-rc.4", only: :dev, runtime: false}
     ]
   end
 end

mix.lock

@@ -1,3 +1,9 @@
-%{"dialyxir": {:hex, :dialyxir, "0.5.1", "b331b091720fd93e878137add264bac4f644e1ddae07a70bf7062c7862c4b952", [], [], "hexpm"},
-  "earmark": {:hex, :earmark, "1.2.4", "99b637c62a4d65a20a9fb674b8cffb8baa771c04605a80c911c4418c69b75439", [], [], "hexpm"},
-  "ex_doc": {:hex, :ex_doc, "0.18.1", "37c69d2ef62f24928c1f4fdc7c724ea04aecfdf500c4329185f8e3649c915baf", [], [{:earmark, "~> 1.1", [hex: :earmark, repo: "hexpm", optional: false]}], "hexpm"}}
+%{
+  "dialyxir": {:hex, :dialyxir, "1.0.0-rc.4", "71b42f5ee1b7628f3e3a6565f4617dfb02d127a0499ab3e72750455e986df001", [:mix], [{:erlex, "~> 0.1", [hex: :erlex, repo: "hexpm", optional: false]}], "hexpm"},
+  "earmark": {:hex, :earmark, "1.3.1", "73812f447f7a42358d3ba79283cfa3075a7580a3a2ed457616d6517ac3738cb9", [:mix], [], "hexpm"},
+  "erlex": {:hex, :erlex, "0.2.1", "cee02918660807cbba9a7229cae9b42d1c6143b768c781fa6cee1eaf03ad860b", [:mix], [], "hexpm"},
+  "ex_doc": {:hex, :ex_doc, "0.19.3", "3c7b0f02851f5fc13b040e8e925051452e41248f685e40250d7e40b07b9f8c10", [:mix], [{:earmark, "~> 1.2", [hex: :earmark, repo: "hexpm", optional: false]}, {:makeup_elixir, "~> 0.10", [hex: :makeup_elixir, repo: "hexpm", optional: false]}], "hexpm"},
+  "makeup": {:hex, :makeup, "0.8.0", "9cf32aea71c7fe0a4b2e9246c2c4978f9070257e5c9ce6d4a28ec450a839b55f", [:mix], [{:nimble_parsec, "~> 0.5.0", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm"},
+  "makeup_elixir": {:hex, :makeup_elixir, "0.13.0", "be7a477997dcac2e48a9d695ec730b2d22418292675c75aa2d34ba0909dcdeda", [:mix], [{:makeup, "~> 0.8", [hex: :makeup, repo: "hexpm", optional: false]}], "hexpm"},
+  "nimble_parsec": {:hex, :nimble_parsec, "0.5.0", "90e2eca3d0266e5c53f8fbe0079694740b9c91b6747f2b7e3c5d21966bba8300", [:mix], [], "hexpm"},
+}

test/org/lexer_test.exs

@@ -28,6 +28,13 @@ defmodule Org.LexerTest do
       {:section_title, 2, "another"},
       {:text, "2"},
       {:section_title, 3, "thing"},
+      {:begin_drawer, "PROPERTIES"},
+      {:property, "Title", "Goldberg Variations"},
+      {:property, "Composer", "J.S. Bach"},
+      {:property, "Artist", "Glenn Gould"},
+      {:property, "Publisher", "Deutsche Grammophon"},
+      {:property, "NDisks", "1"},
+      {:end_drawer},
       {:text, "3"},
       {:section_title, 4, "is nesting"},
       {:text, "4"},

test/org/parser_test.exs

@@ -31,5 +31,15 @@ defmodule Org.ParserTest do
         %Org.CodeBlock{lang: "sql", details: "", lines: ["SELECT * FROM products;"]},
       ]
     end
+
+    test "section with properties", %{doc: doc} do
+      assert Org.section(doc, ["Also", "another", "thing"]).properties == [
+        {:Title, "Goldberg Variations"},
+        {:Composer, "J.S. Bach"},
+        {:Artist, "Glenn Gould"},
+        {:Publisher, "Deutsche Grammophon"},
+        {:NDisks, "1"},
+      ]
+    end
   end
 end

test/org_test.exs

@@ -20,6 +20,13 @@ defmodule OrgTest do
   ** another
   2
   *** thing
+      :PROPERTIES:
+      :Title:     Goldberg Variations
+      :Composer:  J.S. Bach
+      :Artist:    Glenn Gould
+      :Publisher: Deutsche Grammophon
+      :NDisks:    1
+      :END:
   3
   **** is nesting
   4