What is the test for establishing an equitable easement over a landlocked parcel?

¹ This latter use of the equitable easement doctrine is not to be confused with a court's separate but narrower power to establish an easement by necessity. An easement by necessity allows for the creation of an easement that provides access to a landlocked parcel over a neighboring parcel, but only if (1) the two parcels were once commonly owned, (2) an access road is strict[ly] necess[ary], and (3) the prior, common owner never evinced an intent not to have an access road. (Murphy v. Burch (2009) 46 Cal.4th 157, 164165, 92 Cal.Rptr.3d 381, 205 P.3d 289.)