fix: Give error message to users when address has already been validated

Plus other errors.

lib/pleroma/web/twitter_api/controller.ex

@@ -18,10 +18,21 @@ defmodule Pleroma.Web.TwitterAPI.Controller do
   action_fallback(:errors)
 
   def confirm_email(conn, %{"user_id" => uid, "token" => token}) do
-    with %User{} = user <- User.get_cached_by_id(uid),
-         true <- user.local and !user.is_confirmed and user.confirmation_token == token,
-         {:ok, _} <- User.confirm(user) do
+    case User.get_cached_by_id(uid) do
+      %User{local: true, is_confirmed: false, confirmation_token: ^token} = user ->
+        case User.confirm(user) do
+          {:ok, _} ->
             redirect(conn, to: "/")
+
+          {:error, _} ->
+            json_reply(conn, 400, "Unable to confirm")
+        end
+
+      %User{is_confirmed: true} ->
+        json_reply(conn, 400, "Already verified email")
+
+      _ ->
+        json_reply(conn, 400, "Couldn't verify email")
     end
   end
 

test/pleroma/web/twitter_api/controller_test.exs

@@ -38,16 +38,30 @@ test "it confirms the user account", %{conn: conn, user: user} do
       refute user.confirmation_token
     end
 
-    test "it returns 500 if user cannot be found by id", %{conn: conn, user: user} do
-      conn = get(conn, "/api/account/confirm_email/0/#{user.confirmation_token}")
+    test "confirmation is requested twice", %{conn: conn, user: user} do
+      conn = get(conn, "/api/account/confirm_email/#{user.id}/#{user.confirmation_token}")
+      assert 302 == conn.status
 
-      assert 500 == conn.status
+      conn = get(conn, "/api/account/confirm_email/#{user.id}/#{user.confirmation_token}")
+      assert 400 == conn.status
+      assert "Already verified email" == conn.resp_body
+
+      user = User.get_cached_by_id(user.id)
+
+      assert user.is_confirmed
+      refute user.confirmation_token
     end
 
-    test "it returns 500 if token is invalid", %{conn: conn, user: user} do
+    test "it returns 400 if user cannot be found by id", %{conn: conn, user: user} do
+      conn = get(conn, "/api/account/confirm_email/0/#{user.confirmation_token}")
+
+      assert 400 == conn.status
+    end
+
+    test "it returns 400 if token is invalid", %{conn: conn, user: user} do
       conn = get(conn, "/api/account/confirm_email/#{user.id}/wrong_token")
 
-      assert 500 == conn.status
+      assert 400 == conn.status
     end
   end