Lax email validation

lib/pow/ecto/schema/changeset.ex

@@ -241,16 +241,17 @@ defmodule Pow.Ecto.Schema.Changeset do
     Config.get(config, :email_validator, &__MODULE__.validate_email/1)
   end
 
-  @rfc_5332_regexp_no_ip ~r<\A[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\z>
+  @naive_email_regexp ~r/^(?<user>[^\s]+)@(?<domain>[^\s]+\.[^\s]+)$/
 
   @doc """
   Validates an e-mail.
 
-  Complies to RFC 5332 spec without IP.
+  This is a naive implementation that only expects the format
+  `<username>@<domain>`. The domain requires a TLD.
   """
   @spec validate_email(binary()) :: :ok | :error | {:error, any()}
   def validate_email(email) do
-    case email =~ @rfc_5332_regexp_no_ip do
+    case email =~ @naive_email_regexp do
       true  -> :ok
       false -> :error
     end

test/pow/ecto/schema/changeset_test.exs

@@ -39,10 +39,6 @@ defmodule Pow.Ecto.Schema.ChangesetTest do
       refute changeset.valid?
       assert changeset.errors[:email] == {"has invalid format", [validator: &Pow.Ecto.Schema.Changeset.validate_email/1]}
 
-      changeset = User.changeset(%User{}, Map.put(@valid_params, "email", ".wooly@example.com"))
-      refute changeset.valid?
-      assert changeset.errors[:email] == {"has invalid format", [validator: &Pow.Ecto.Schema.Changeset.validate_email/1]}
-
       changeset = User.changeset(%User{}, @valid_params)
       assert changeset.valid?
     end
@@ -229,4 +225,19 @@ defmodule Pow.Ecto.Schema.ChangesetTest do
       assert_received {:password_verify, "secret1234", "hash"}
     end
   end
+
+  test "validate_email/1" do
+    assert Changeset.validate_email(".wooly@example.com") == :ok
+    assert Changeset.validate_email("john.doe@example.com") == :ok
+    assert Changeset.validate_email("john.doe+spam@example.com") == :ok
+    assert Changeset.validate_email("john.doe@subdomain.example.com") == :ok
+    assert Changeset.validate_email("☞@example.com") == :ok
+    assert Changeset.validate_email("はな@example.com") == :ok
+
+    refute Changeset.validate_email("invalid") == :ok
+    refute Changeset.validate_email("john.doe@") == :ok
+    refute Changeset.validate_email("example.com") == :ok
+    refute Changeset.validate_email("@example.com") == :ok
+    refute Changeset.validate_email("john@example") == :ok
+  end
 end