Resolutely testate? (4,1,4)

I believe the answer is:

with a will

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'resolutely' is the definition.
(thesaurus)

I don't understand the rest of the clue.

(Other definitions for with a will that I've seen before include "Anne put up so" , "energetically and resolutely" , "vigorously" , "How one should leave things" , "Zealously" .)

I've seen this clue in the Sydney Morning Herald.

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