put to the test
Try or check out something or someone, as in This tall grass will put our new lawnmower to the test, or Let's put Harry to the test and see if he knows the last 20 World Series winners. [Mid-1600s]
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.