Added body parser

lib/code_corps/github/event/pull_request/body_parser.ex

@@ -0,0 +1,25 @@
+defmodule CodeCorps.GitHub.Event.PullRequest.BodyParser do
+  @moduledoc ~S"""
+  In charge of extracting ids from markdown content, paired to a predefined list
+  of keywords.
+  """
+
+  @doc ~S"""
+  Searchs for GitHub closing keyword format inside a content string. Returns all
+  unique ids matched, as integers.
+  """
+  @spec extract_closing_ids(String.t) :: list(integer)
+  def extract_closing_ids(content) when is_binary(content) do
+    ~w(close closes closed fix fixes fixed resolve resolves resolved)
+    |> matching_regex()
+    |> Regex.scan(content) # [["closes #1", "closes", "1"], ["fixes #2", "fixes", "2"]]
+    |> Enum.map(&List.last/1) # ["1", "2"]
+    |> Enum.map(&String.to_integer/1) # [1, 2]
+    |> Enum.uniq
+  end
+
+  defp matching_regex(keywords) do
+    matches = keywords |> Enum.join("|")
+    ~r/(?:(#{matches}))\s+#(\d+)/i
+  end
+end

test/lib/code_corps/github/event/pull_request/body_parser_test.exs

@@ -0,0 +1,32 @@
+defmodule CodeCorps.GitHub.Event.PullRequest.BodyParserTest do
+  @moduledoc false
+
+  use ExUnit.Case, async: true
+
+
+  alias CodeCorps.{
+    GitHub.Event.PullRequest.BodyParser
+  }
+
+  describe "extract_closing_ids/1" do
+    test "correctly extracts ids using supported closing keywords" do
+      content =
+        """
+        close #2, closes #3 closed #4: fixed #5 fixes #6 fix #7.
+        resolve #8 resolves #9 #resolved #10
+        """
+
+      assert content |> BodyParser.extract_closing_ids == 2..10 |> Enum.to_list
+    end
+
+    test "only returns unique results" do
+      content =
+        """
+        close #2, closes #2 closed #3: fixed #4 fixes #5 fix #6.
+        resolve #7 resolves #8 #resolved #8
+        """
+
+      assert content |> BodyParser.extract_closing_ids == 2..8 |> Enum.to_list
+    end
+  end
+end