There is no edit action in Shree :: CheckoutController, but it displays checkout / edit.html.erb. Link to the superclass. The following recommendation from spree documentation
The edit action renders the checkout/edit.html.erb template, which then renders a partial with the current state, such as app/views/spree/checkout/address.html.erb. This partial shows state-specific fields for the user to fill in. If you choose to customize the checkout flow to add a new state, you will need to create a new partial for this state.
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