Support returning info data

Helpful if someone wants to use the generated Info data, but doesn't
want to jump through the hoops of capturing IO

lib/vintage_net.ex

@@ -71,6 +71,7 @@ defmodule VintageNet do
   Valid options for `VintageNet.info/1`
 
   * `:redact` - Whether to hide passwords and similar information from the output (defaults to `true`)
+  * `:return` - Skip printing and return the formatted chardata
   """
   @type info_options :: {:redact, boolean()}
 

lib/vintage_net/info.ex

@@ -8,14 +8,24 @@ defmodule VintageNet.Info do
   """
   @spec info([VintageNet.info_options()]) :: :ok
   def info(opts \\ []) do
+    chardata = info_chardata(opts)
+
+    if opts[:return] == true do
+      to_string(chardata)
+    else
+      IO.write(chardata)
+    end
+  end
+
+  defp info_chardata(opts) do
     case version() do
       :not_loaded ->
-        IO.puts("VintageNet hasn't been loaded yet. Try again soon.")
+        "VintageNet hasn't been loaded yet. Try again soon."
 
       version ->
         ifnames = interfaces_to_show()
 
-        IO.write([format_header(version), format_interfaces(ifnames, opts)])
+        [format_header(version), format_interfaces(ifnames, opts)]
     end
   end
 

test/vintage_net/info_test.exs

@@ -93,6 +93,14 @@ defmodule VintageNet.InfoTest do
     assert output =~ "No interfaces"
   end
 
+  test "info can return chardata" do
+    output = Info.info(return: true)
+
+    assert output =~ "All interfaces"
+    assert output =~ "Available interfaces"
+    assert output =~ "No interfaces"
+  end
+
   test "info works with a configured interface" do
     capture_log(fn ->
       :ok = VintageNet.configure("eth0", %{type: VintageNetTest.TestTechnology})