[GROOVY-9991] STC: error for closure not matching functional interface method's parameter count

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.8, 4.0.0-alpha-3
• Assignee: Eric Milles
• Reporter: Eric Milles
• Created: 20/Mar/21 00:54
• Updated: 02/May/21 09:16
• Resolved: 23/Mar/21 03:28

Description

Consider the following:

import java.util.function.*
@groovy.transform.TypeChecked
void test() {
  Consumer c0 = { print it } // error
  Consumer c1 = { x -> } // all good
  Supplier s0 = { -> "" } // all good
  Supplier s1 = { "" } // all good
}

The implicit parameter closure literal (no arrow) should match for 0 or 1 parameter method targets.