Raise errors to suggest completing class configuration

lib/active_resource/base.rb

@@ -795,6 +795,7 @@ def primary_key
       # Gets the \prefix for a resource's nested URL (e.g., <tt>prefix/collectionname/1.json</tt>)
       # This method is regenerated at runtime based on what the \prefix is set to.
       def prefix(options = {})
+        raise ArgumentError, "Missing site URI" unless site
         default = site.path
         default << "/" unless default[-1..-1] == "/"
         # generate the actual method based on the current site path
@@ -899,6 +900,7 @@ def element_path(id, prefix_options = {}, query_options = nil)
       #   # => https://37s.sunrise.com/posts/5/comments/1.json?active=1
       #
       def element_url(id, prefix_options = {}, query_options = nil)
+        raise ArgumentError, "Missing site URI" unless site
         URI.join(site, element_path(id, prefix_options, query_options)).to_s
       end
 
@@ -971,6 +973,7 @@ def collection_path(prefix_options = {}, query_options = nil)
       #   # => https://example.com/posts/5/comments.json?active=1
       #
       def collection_url(prefix_options = {}, query_options = nil)
+        raise ArgumentError, "Missing site URI" unless site
         URI.join(site, collection_path(prefix_options, query_options)).to_s
       end
 

test/cases/base_test.rb

@@ -33,6 +33,20 @@ def teardown
   # Tests relating to setting up the API-connection configuration
   ########################################################################
 
+  def test_site_missing_error_message
+    Person.site = nil
+
+    assert_raises ArgumentError, match: "Missing site URI" do
+      Person.find(1)
+    end
+    assert_raises ArgumentError, match: "Missing site URI" do
+      Person.element_url(1)
+    end
+    assert_raises ArgumentError, match: "Missing site URI" do
+      Person.collection_url(1)
+    end
+  end
+
   def test_site_accessor_accepts_uri_or_string_argument
     site = URI.parse("http://localhost")
 

test/cases/connection_test.rb

@@ -345,6 +345,12 @@ def test_disable_net_connection
     end
   end
 
+  def test_site_missing_error_message
+    assert_raises ArgumentError, match: "Missing site URI" do
+      ActiveResource::Connection.new(nil)
+    end
+  end
+
   def keep_net_connection_status
     old = ActiveResource::HttpMock.net_connection_enabled?
     begin