[Fix rails#48922] Use context from the encrypted attribute type in encrypted_attribute?

Also fix implementation of TestEncryptor#encrypted?

The assertions fail because encrypted_attribute? delegates a decryption
attempt to the default encryptor (instead of the one configured) to
check if the value is actually encrypted.

Author: maximerety

activerecord/CHANGELOG.md

@@ -1,3 +1,7 @@
+*   Fix `encrypted_attribute?` to take into account context properties passed to `encrypts`.
+
+    *Maxime Réty*
+
 *   The object returned by `explain` now responds to `pluck`, `first`,
     `last`, `average`, `count`, `maximum`, `minimum`, and `sum`. Those
     new methods run `EXPLAIN` on the corresponding queries:

activerecord/lib/active_record/encryption/encryptable_record.rb

@@ -144,7 +144,13 @@ def validate_column_size(attribute_name)
 
       # Returns whether a given attribute is encrypted or not.
       def encrypted_attribute?(attribute_name)
-        ActiveRecord::Encryption.encryptor.encrypted? read_attribute_before_type_cast(attribute_name)
+        name = attribute_name.to_s
+        name = self.class.attribute_aliases[name] || name
+
+        return false unless self.class.encrypted_attributes&.include? name.to_sym
+
+        type = type_for_attribute(name)
+        type.encrypted? read_attribute_before_type_cast(name)
       end
 
       # Returns the ciphertext for +attribute_name+.

activerecord/lib/active_record/encryption/encrypted_attribute_type.rb

@@ -44,6 +44,10 @@ def serialize(value)
         end
       end
 
+      def encrypted?(value)
+        with_context { encryptor.encrypted? value }
+      end
+
       def changed_in_place?(raw_old_value, new_value)
         old_value = raw_old_value.nil? ? nil : deserialize(raw_old_value)
         old_value != new_value

activerecord/test/cases/encryption/encryption_schemes_test.rb

@@ -9,6 +9,7 @@ class ActiveRecord::Encryption::EncryptionSchemesTest < ActiveRecord::Encryption
 
     author = create_author_with_name_encrypted_with_previous_scheme
     assert_equal "dhh", author.reload.name
+    assert author.encrypted_attribute? :name
   end
 
   test "when defining previous encryption schemes, you still get Decryption errors when using invalid clear values" do
@@ -24,6 +25,7 @@ class ActiveRecord::Encryption::EncryptionSchemesTest < ActiveRecord::Encryption
   test "use a custom encryptor" do
     author = EncryptedAuthor1.create name: "1"
     assert_equal "1", author.name
+    assert author.encrypted_attribute? :name
   end
 
   test "support previous contexts" do
@@ -32,10 +34,12 @@ class ActiveRecord::Encryption::EncryptionSchemesTest < ActiveRecord::Encryption
     author = EncryptedAuthor2.create name: "2"
     assert_equal "2", author.name
     assert_equal author, EncryptedAuthor2.find_by_name("2")
+    assert author.encrypted_attribute? :name
 
     Author.find(author.id).update! name: "1"
     assert_equal "1", author.reload.name
     assert_equal author, EncryptedAuthor2.find_by_name("1")
+    assert_not author.encrypted_attribute? :name
   end
 
   test "use global previous schemes to decrypt data encrypted with previous schemes" do
@@ -191,7 +195,9 @@ def decrypt(encrypted_text, key_provider: nil, cipher_options: {})
       end
 
       def encrypted?(text)
-        text == encrypted_text
+        decrypt(text)
+      rescue ActiveRecord::Encryption::Errors::Decryption
+        false
       end
     end