testy vs petulant

testy and petulant both are adjectives.

Word	Noun	Adjective	Verb	Adverb
testy	No	Yes	No	No
petulant	No	Yes	No	No

As adjectives, testy and petulant are synonyms defined as:

Other synonyms of testy include cranky, fractious, irritable, nettlesome, peckish, peevish, pettish, scratchy, techy, tetchy.

testy (adjective)	petulant (adjective)
easily irritated or annoyed	easily irritated or annoyed