Remove Rubocop TODO around guard clauses

Removes Rubocop TODO around guard clauses and fixes the outstanding
offenses.

This is starting to get into territory that feels of more dubious value
to me, but at least it did get me writing a couple more tests, so let's
see how it goes by keeping this on.

.rubocop_todo.yml

@@ -65,12 +65,3 @@ Style/ClassVars:
 # Offense count: 51
 Style/Documentation:
   Enabled: false
-
-# Offense count: 5
-# Configuration parameters: MinBodyLength.
-Style/GuardClause:
-  Exclude:
-    - 'lib/stripe/alipay_account.rb'
-    - 'lib/stripe/source.rb'
-    - 'lib/stripe/stripe_client.rb'
-    - 'lib/stripe/stripe_object.rb'

lib/stripe/alipay_account.rb

@@ -6,9 +6,12 @@ module Stripe
     OBJECT_NAME = "alipay_account".freeze
 
     def resource_url
-      if respond_to?(:customer) && !customer.nil?
-        "#{Customer.resource_url}/#{CGI.escape(customer)}/sources/#{CGI.escape(id)}"
+      if !respond_to?(:customer) || customer.nil?
+        raise NotImplementedError,
+              "Alipay accounts cannot be accessed without a customer ID."
       end
+
+      "#{Customer.resource_url}/#{CGI.escape(customer)}/sources/#{CGI.escape(id)}"
     end
 
     def self.update(_id, _params = nil, _opts = nil)

lib/stripe/source.rb

@@ -6,13 +6,16 @@ module Stripe
     OBJECT_NAME = "source".freeze
 
     def delete(params = {}, opts = {})
-      if respond_to?(:customer) && !customer.nil? && !customer.empty?
-        url = "#{Customer.resource_url}/#{CGI.escape(customer)}/sources/#{CGI.escape(id)}"
-        resp, opts = request(:delete, url, params, Util.normalize_opts(opts))
-        initialize_from(resp.data, opts)
-      else
-        raise NotImplementedError, "Source objects cannot be deleted, they can only be detached from customer objects. This source object does not appear to be currently attached to a customer object."
+      if !respond_to?(:customer) || customer.nil? || customer.empty?
+        raise NotImplementedError,
+              "Source objects cannot be deleted, they can only be detached " \
+              "from customer objects. This source object does not appear to " \
+              "be currently attached to a customer object."
       end
+
+      url = "#{Customer.resource_url}/#{CGI.escape(customer)}/sources/#{CGI.escape(id)}"
+      resp, opts = request(:delete, url, params, Util.normalize_opts(opts))
+      initialize_from(resp.data, opts)
     end
 
     def verify(params = {}, opts = {})

lib/stripe/stripe_client.rb

@@ -181,12 +181,12 @@ module Stripe
           "if you have any questions."
       end
 
-      if api_key =~ /\s/
-        raise AuthenticationError, "Your API key is invalid, as it contains " \
-          "whitespace. (HINT: You can double-check your API key from the " \
-          "Stripe web interface. See https://stripe.com/api for details, or " \
-          "email support@stripe.com if you have any questions.)"
-      end
+      return unless api_key =~ /\s/
+
+      raise AuthenticationError, "Your API key is invalid, as it contains " \
+        "whitespace. (HINT: You can double-check your API key from the " \
+        "Stripe web interface. See https://stripe.com/api for details, or " \
+        "email support@stripe.com if you have any questions.)"
     end
 
     def execute_request_with_rescues(api_base, context)
@@ -458,12 +458,13 @@ module Stripe
                      body: body,
                      idempotency_key: context.idempotency_key,
                      request_id: context.request_id)
-      if context.request_id
-        Util.log_debug("Dashboard link for request",
-                       idempotency_key: context.idempotency_key,
-                       request_id: context.request_id,
-                       url: Util.request_id_dashboard_url(context.request_id, context.api_key))
-      end
+
+      return unless context.request_id
+
+      Util.log_debug("Dashboard link for request",
+                     idempotency_key: context.idempotency_key,
+                     request_id: context.request_id,
+                     url: Util.request_id_dashboard_url(context.request_id, context.api_key))
     end
     private :log_response
 

lib/stripe/stripe_object.rb

@@ -278,11 +278,12 @@ module Stripe
       begin
         super
       rescue NoMethodError => e
-        if @transient_values.include?(name)
-          raise NoMethodError, e.message + ".  HINT: The '#{name}' attribute was set in the past, however.  It was then wiped when refreshing the object with the result returned by Stripe's API, probably as a result of a save().  The attributes currently available on this object are: #{@values.keys.join(', ')}"
-        else
-          raise
-        end
+        # If we notice the accessed name if our set of transient values we can
+        # give the user a slightly more helpful error message. If not, just
+        # raise right away.
+        raise unless @transient_values.include?(name)
+
+        raise NoMethodError, e.message + ".  HINT: The '#{name}' attribute was set in the past, however.  It was then wiped when refreshing the object with the result returned by Stripe's API, probably as a result of a save().  The attributes currently available on this object are: #{@values.keys.join(', ')}"
       end
     end
 

test/stripe/alipay_account_test.rb

@@ -2,6 +2,24 @@ require File.expand_path("../../test_helper", __FILE__)
 
 module Stripe
   class AlipayAccountTest < Test::Unit::TestCase
+    context "#resource_url" do
+      should "return a resource URL" do
+        alipay_account = Stripe::AlipayAccount.construct_from(
+          id: "aliacc_123",
+          customer: "cus_123"
+        )
+        assert_equal "/v1/customers/cus_123/sources/aliacc_123",
+                     alipay_account.resource_url
+      end
+
+      should "raise without a customer" do
+        alipay_account = Stripe::AlipayAccount.construct_from(id: "aliacc_123")
+        assert_raises NotImplementedError do
+          alipay_account.resource_url
+        end
+      end
+    end
+
     should "raise on #retrieve" do
       assert_raises NotImplementedError do
         Stripe::AlipayAccount.retrieve("aliacc_123")