Neither Command::new nor cargo_bin_cmd! return something that can be unwrapped:

• assert_cmd/src/macros.rs

  Lines 51 to 53 in ef752de

  	/// let mut cmd = Command::new(cargo_bin!())
  	/// .unwrap();
  	/// let output = cmd.unwrap();

• assert_cmd/src/macros.rs

  Lines 81 to 83 in ef752de

  	/// let mut cmd = cargo_bin_cmd!()
  	/// .unwrap();
  	/// let output = cmd.unwrap();

I would have proposed something, but I wasn't sure how to handle the let output = cmd.unwrap(); parts.

FWIW, these changes seem pretty recent (less than 24 hours old).