Allow checking KeyPairInfo for equality

GnuPG-bug-id: 4876

src/smartcard/keypairinfo.cpp

@@ -82,3 +82,19 @@ void KeyPairInfo::update(const KeyPairInfo &other)
         algorithm = other.algorithm;
     }
 }
+
+// C++20: Replace with defaulted equality operator
+bool KeyPairInfo::operator==(const KeyPairInfo &other) const
+{
+    return keyRef == other.keyRef
+        && grip == other.grip
+        && usage == other.usage
+        && keyTime == other.keyTime
+        && algorithm == other.algorithm;
+}
+
+// C++20: Remove
+bool KeyPairInfo::operator!=(const KeyPairInfo &other) const
+{
+    return !operator==(other);
+}

src/smartcard/keypairinfo.h

@@ -24,6 +24,9 @@ struct KeyPairInfo {
 
     void update(const KeyPairInfo &other);
 
+    bool operator==(const KeyPairInfo &other) const;
+    bool operator!=(const KeyPairInfo &other) const;
+
     std::string keyRef;
     std::string grip;
     std::string usage;