convert response to an %Error{} when raising

lib/oauth2/request.ex

@@ -43,8 +43,17 @@ defmodule OAuth2.Request do
     case request(method, client, url, body, headers, opts) do
       {:ok, resp} ->
         resp
-      {:error, %{status_code: code, body: body}} ->
-        raise %Error{reason: "Server responded with status: #{code}; body: #{inspect body}"}
+      {:error, %{status_code: code, headers: headers, body: body}} ->
+        raise %Error{reason: """
+        Server responded with status: #{code}
+
+        Headers:
+
+        #{Enum.reduce(headers, "", fn {k, v}, acc -> acc <> "#{k}: #{v}\n" end)}
+        Body:
+
+        #{inspect body}
+        """}
       {:error, error} ->
         raise error
     end

mix.exs

@@ -7,7 +7,7 @@ defmodule OAuth2.Mixfile do
     [app: :oauth2,
      name: "OAuth2",
      version: @version,
-     elixir: "~> 1.2 or ~> 1.3",
+     elixir: "~> 1.2",
      deps: deps(),
      package: package(),
      description: description(),

test/oauth2/client_test.exs

@@ -284,7 +284,7 @@ defmodule OAuth2.ClientTest do
       json(conn, 400, %{error: "error"})
     end
 
-    assert_raise OAuth2.Error, ~r/Server responded with status: 400; body:/, fn ->
+    assert_raise OAuth2.Error, ~r/Server responded with status: 400/, fn ->
       Client.get!(client, "/api/error")
     end
   end