From b273a1662b9fb67f0e3004998017b3d8bd367a8f Mon Sep 17 00:00:00 2001
From: Magne Land <magne.land@appfolio.com>
Date: Thu, 12 Oct 2023 17:53:54 -0700
Subject: [PATCH] Add type check to key_base '==' operator

---
 lib/jwt/jwk/key_base.rb |  2 +-
 spec/jwk/hmac_spec.rb   | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/lib/jwt/jwk/key_base.rb b/lib/jwt/jwk/key_base.rb
index 6f0df55a..856a5d2d 100644
--- a/lib/jwt/jwk/key_base.rb
+++ b/lib/jwt/jwk/key_base.rb
@@ -38,7 +38,7 @@ def []=(key, value)
       end
 
       def ==(other)
-        self[:kid] == other[:kid]
+        other.is_a?(::JWT::JWK::KeyBase) && self[:kid] == other[:kid]
       end
 
       alias eql? ==
diff --git a/spec/jwk/hmac_spec.rb b/spec/jwk/hmac_spec.rb
index dcc7d4ce..7702e779 100644
--- a/spec/jwk/hmac_spec.rb
+++ b/spec/jwk/hmac_spec.rb
@@ -82,4 +82,36 @@
       end
     end
   end
+
+  describe '#==' do
+    it 'is equal to itself' do
+      other = jwk
+      expect(jwk == other).to eq true
+    end
+
+    it 'is equal to a clone of itself' do
+      other = jwk.clone
+      expect(jwk == other).to eq true
+    end
+
+    it 'is not equal to nil' do
+      other = nil
+      expect(jwk == other).to eq false
+    end
+
+    it 'is not equal to boolean true' do
+      other = true
+      expect(jwk == other).to eq false
+    end
+
+    it 'is not equal to a non-key' do
+      other = Object.new
+      expect(jwk == other).to eq false
+    end
+
+    it 'is not equal to a different key' do
+      other = described_class.new('other-key')
+      expect(jwk == other).to eq false
+    end
+  end
 end