“digs.” The verbs in this verse are past tense, “has dug…has hollowed…has fallen,” but the past tense is often used for emphasis—what will happen—rather than to accurately represent time, which explains why many English versions do not use the past tense in this verse (cp. CJB; ESV; NAB; NET; NIV; NLT; NRSV). In this case, the point is that that person who does evil by digging a pit (physically or metaphorically) to trap others will himself by trapped.
“he falls into the pit that he made.” It is a consistent theme through Scripture that evil people bring evil upon themselves (see commentary on Prov. 1:18).