Mock Method Chain Calls With RSpec

Generally with RSpec you mock one method call at a time:

allow(User).to receive(:new).and_return(true)

Sometimes you are dealing with code that involves a chain of method calls.

User
  .new
  .approve
  .send_welcome_email

If it becomes unreasonable to mock out each individual method, you can instead mock out the chain of calls.

allow(User).to receive_message_chain('new.approve.send_welcome_email')

Alternatively, you can write this as:

allow(User).to receive_message_chain(:new, :approve, :send_welcome_email)

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