Restore nested JWT max depth constants

Author: ydah

lib/jwt/nested_token.rb

@@ -23,6 +23,9 @@ module JWT
   #
   # @see https://datatracker.ietf.org/doc/html/rfc7519#section-5.2 RFC 7519 Section 5.2
   class NestedToken
+    CTY_JWT = 'JWT'
+    MAX_DEPTH = 10
+
     # @return [String] the current JWT string represented by this instance.
     attr_reader :jwt
 
@@ -48,7 +51,7 @@ def sign!(algorithm:, key:, header: {})
       signer = JWA.create_signer(algorithm: algorithm, key: key)
       outer_header = (header || {})
                      .transform_keys(&:to_s)
-                     .merge('cty' => 'JWT') # The content type header value for nested JWTs as per RFC 7519.
+                     .merge('cty' => CTY_JWT)
 
       outer_header.merge!(signer.jwa.header) { |_header_key, old, _new| old }
 

spec/jwt/nested_token_spec.rb

@@ -173,25 +173,6 @@
       end.to raise_error(JWT::DecodeError, 'Expected 1 key configurations, got 2')
     end
 
-    it 'raises DecodeError when nesting exceeds max_depth' do
-      level_1_jwt = JWT.encode(inner_payload, 'secret_1', 'HS256')
-      level2 = described_class.new(level_1_jwt)
-      level2.sign!(algorithm: 'HS256', key: 'secret_2')
-      level3 = described_class.new(level2.jwt)
-      level3.sign!(algorithm: 'HS256', key: 'secret_3')
-
-      expect do
-        described_class.new(level3.jwt).verify_signatures!(
-          keys: [
-            { algorithm: 'HS256', key: 'secret_3' },
-            { algorithm: 'HS256', key: 'secret_2' },
-            { algorithm: 'HS256', key: 'secret_1' }
-          ],
-          max_depth: 2
-        )
-      end.to raise_error(JWT::DecodeError, 'Nested JWT exceeds maximum depth of 2')
-    end
-
     context 'with different algorithms at each level' do
       let(:rsa_private) { test_pkey('rsa-2048-private.pem') }
       let(:rsa_public) { rsa_private.public_key }