Remove code and specs related to dynamic checkout workflow, we have a static workflow defines in the Order class

app/models/spree/order.rb

@@ -553,10 +553,6 @@ module Spree
       line_item_adjustments.destroy_all
     end
 
-    def has_step?(step)
-      checkout_steps.include?(step)
-    end
-
     def state_changed(name)
       state = "#{name}_state"
       return unless persisted?
@@ -803,7 +799,6 @@ module Spree
     end
 
     def has_available_shipment
-      return unless has_step?("delivery")
       return unless address?
       return unless ship_address&.valid?
       # errors.add(:base, :no_shipping_methods_available) if available_shipping_methods.empty?

app/models/spree/order/checkout.rb

@@ -9,7 +9,6 @@ module Spree
           class_attribute :previous_states
           class_attribute :checkout_flow
           class_attribute :checkout_steps
-          class_attribute :removed_transitions
 
           def self.checkout_flow(&block)
             if block_given?
@@ -24,7 +23,6 @@ module Spree
             self.checkout_steps = {}
             self.next_event_transitions = []
             self.previous_states = [:cart]
-            self.removed_transitions = []
 
             # Build the checkout flow using the checkout_flow defined either
             # within the Order class, or a decorator for that class.
@@ -95,43 +93,6 @@ module Spree
             end
           end
 
-          def self.insert_checkout_step(name, options = {})
-            before = options.delete(:before)
-            after = options.delete(:after) unless before
-            after = checkout_steps.keys.last unless before || after
-
-            cloned_steps = checkout_steps.clone
-            cloned_removed_transitions = removed_transitions.clone
-            checkout_flow do
-              cloned_steps.each_pair do |key, value|
-                go_to_state(name, options) if key == before
-                go_to_state(key, value)
-                go_to_state(name, options) if key == after
-              end
-              cloned_removed_transitions.each do |transition|
-                remove_transition(transition)
-              end
-            end
-          end
-
-          def self.remove_checkout_step(name)
-            cloned_steps = checkout_steps.clone
-            cloned_removed_transitions = removed_transitions.clone
-            checkout_flow do
-              cloned_steps.each_pair do |key, value|
-                go_to_state(key, value) unless key == name
-              end
-              cloned_removed_transitions.each do |transition|
-                remove_transition(transition)
-              end
-            end
-          end
-
-          def self.remove_transition(options = {})
-            removed_transitions << options
-            next_event_transitions.delete(find_transition(options))
-          end
-
           def self.find_transition(options = {})
             return nil if options.nil? || !options.include?(:from) || !options.include?(:to)
 
@@ -173,10 +134,6 @@ module Spree
             checkout_steps.index(step)
           end
 
-          def self.removed_transitions
-            @removed_transitions ||= []
-          end
-
           def can_go_to_state?(state)
             return false unless self.state.present? &&
                                 checkout_step?(state) &&

spec/models/spree/order/checkout_spec.rb

@@ -30,16 +30,6 @@ describe Spree::Order::Checkout do
       expect(Spree::Order.find_transition({ foo: :bar, baz: :dog })).to be_falsy
     end
 
-    it '.remove_transition' do
-      options = { from: transitions.first.keys.first, to: transitions.first.values.first }
-      allow(Spree::Order).to receive(:next_event_transition).and_return([options])
-      expect(Spree::Order.remove_transition(options)).to be_truthy
-    end
-
-    it '.remove_transition when contract was broken' do
-      expect(Spree::Order.remove_transition(nil)).to be_falsy
-    end
-
     context "#checkout_steps" do
       context "when payment not required" do
         before { allow(order).to receive_messages payment_required?: false }
@@ -232,73 +222,6 @@ describe Spree::Order::Checkout do
     end
   end
 
-  context "insert checkout step" do
-    before do
-      @old_checkout_flow = Spree::Order.checkout_flow
-      Spree::Order.class_eval do
-        insert_checkout_step :new_step, before: :address
-      end
-    end
-
-    after do
-      Spree::Order.checkout_flow(&@old_checkout_flow)
-    end
-
-    it "should maintain removed transitions" do
-      transition = Spree::Order.find_transition(from: :delivery, to: :confirm)
-      expect(transition).to be_nil
-    end
-
-    context "before" do
-      before do
-        Spree::Order.class_eval do
-          insert_checkout_step :before_address, before: :address
-        end
-      end
-
-      specify do
-        order = Spree::Order.new
-        expect(order.checkout_steps).to eq %w(new_step before_address address delivery complete)
-      end
-    end
-
-    context "after" do
-      before do
-        Spree::Order.class_eval do
-          insert_checkout_step :after_address, after: :address
-        end
-      end
-
-      specify do
-        order = Spree::Order.new
-        expect(order.checkout_steps).to eq %w(new_step address after_address delivery complete)
-      end
-    end
-  end
-
-  context "remove checkout step" do
-    before do
-      @old_checkout_flow = Spree::Order.checkout_flow
-      Spree::Order.class_eval do
-        remove_checkout_step :address
-      end
-    end
-
-    after do
-      Spree::Order.checkout_flow(&@old_checkout_flow)
-    end
-
-    it "should maintain removed transitions" do
-      transition = Spree::Order.find_transition(from: :delivery, to: :confirm)
-      expect(transition).to be_nil
-    end
-
-    specify do
-      order = Spree::Order.new
-      expect(order.checkout_steps).to eq %w(delivery complete)
-    end
-  end
-
   describe 'event :restart_checkout' do
     let(:order) { build_stubbed(:order) }