Use OTP::URI for HOTP#provisioning_uri generation

lib/rotp/hotp.rb

@@ -25,12 +25,7 @@ def verify(otp, counter, retries: 0)
     # @param [Integer] initial_count starting counter value, defaults to 0
     # @return [String] provisioning uri
     def provisioning_uri(name, initial_count = 0)
-      params = {
-        secret: secret,
-        counter: initial_count,
-        digits: digits == DEFAULT_DIGITS ? nil : digits
-      }
-      encode_params("otpauth://hotp/#{Addressable::URI.escape(name)}", params)
+      OTP::URI.new(self, account_name: name, counter: initial_count).to_s
     end
   end
 end

spec/lib/rotp/hotp_spec.rb

@@ -108,29 +108,14 @@
   end
 
   describe '#provisioning_uri' do
-    let(:uri)    { hotp.provisioning_uri('mark@percival') }
-    let(:params) { CGI.parse URI.parse(uri).query }
-
-    it 'has the correct format' do
-      expect(uri).to match %r{\Aotpauth:\/\/hotp.+}
-    end
-
-    it 'includes the secret as parameter' do
-      expect(params['secret'].first).to eq 'a' * 32
-    end
-
-    context 'with default digits' do
-      it 'does not include digits parameter with default digits' do
-        expect(params['digits'].first).to be_nil
-      end
+    it 'accepts the account name' do
+      expect(hotp.provisioning_uri('mark@percival'))
+        .to eq 'otpauth://hotp/mark%40percival?secret=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa&counter=0'
     end
 
-    context 'with non-default digits' do
-      let(:hotp) { ROTP::HOTP.new('a' * 32, digits: 8) }
-
-      it 'includes digits parameter' do
-        expect(params['digits'].first).to eq '8'
-      end
+    it 'also accepts a custom counter value' do
+      expect(hotp.provisioning_uri('mark@percival', 17))
+        .to eq 'otpauth://hotp/mark%40percival?secret=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa&counter=17'
     end
   end
 end