Fix script tag validation with JWT signed fields

lib/intercom-rails/script_tag.rb

@@ -54,7 +54,7 @@ def valid?
       return false if user_details[:excluded_user] == true
       valid = user_details[:app_id].present?
       unless @show_everywhere
-        valid = valid && (user_details[:user_id] || user_details[:email]).present?
+        valid = valid && @has_identity
       end
       if nonce
         valid = valid && valid_nonce?
@@ -146,6 +146,8 @@ def user_details=(user_details)
       @user_details = @user_details.with_indifferent_access.tap do |u|
         [:email, :name, :user_id].each { |k| u.delete(k) if u[k].nil? }
 
+        @has_identity = (u[:user_id] || u[:email]).present?
+
         if secret.present?
           if jwt_enabled && u[:user_id].present?
             u[:intercom_user_jwt] ||= generate_jwt

spec/script_tag_spec.rb

@@ -443,6 +443,22 @@ def user
         expect(decoded_payload['name']).to be_nil
       end
 
+      it 'remains valid when both user_id and email are signed fields' do
+        IntercomRails.config.jwt.signed_user_fields = [:user_id, :email]
+        script_tag = ScriptTag.new(
+          user_details: {
+            user_id: '1234',
+            email: 'test@example.com'
+          },
+          jwt_enabled: true
+        )
+
+        expect(script_tag).to be_valid
+        expect(script_tag.intercom_settings[:intercom_user_jwt]).to be_present
+        expect(script_tag.intercom_settings[:user_id]).to be_nil
+        expect(script_tag.intercom_settings[:email]).to be_nil
+      end
+
       it 'respects empty signed_user_fields configuration' do
         IntercomRails.config.jwt.signed_user_fields = []
         script_tag = ScriptTag.new(