[GROOVY-10270] Cannot initialize parameterized class with lambda without cast

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 4.0.0-alpha-3, 4.0.0-beta-1, 3.0.9
• Fix Version/s: 2.5.22, 3.0.17, 4.0.11
• Component/s: Static compilation, Static Type Checker
• Assignee: Eric Milles
• Reporter: Stefanos Chaliasos
• Created: 29/Sep/21 08:08
• Updated: 05/Apr/23 02:44
• Resolved: 18/Mar/23 16:05

Description

I have the following Groovy program.

import java.util.function.Function;


@groovy.transform.TypeChecked
class Main {
   static final void foo(Function<Short, Byte> x) {}

   public static final void main() {
     foo({Short y -> (Byte) y}) // works
     Cls cls = new Cls({Short y -> (Byte) y}) // works
     PCls<Function<Short, Byte>> pcls1 = new PCls<Function<Short, Byte>>({Short y -> (Byte) y} as Function<Short, Byte>) // works
     PCls<Function<Short, Byte>> pcls2 = new PCls<Function<Short, Byte>>({Short y -> (Byte) y}) // fails
   }
}

class Cls {
  public Function<Short, Byte> f

  public Cls(Function<Short, Byte> f) {
     this.f = f
  }
}

class PCls <T> {
   public T f

   public PCls(T f) {
      this.f = f
   }
}

Actual Behavior

The program does not compile, and I get the following error.

org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed:
Main.groovy: 14: [Static type checking] - Cannot call PCls#<init>(java.util.function.Function<java.lang.Short, java.lang.Byte>) with arguments [groovy.lang.Closure]
@ line 14, column 41.
unction<Short, Byte>> pcls2 = new PCls<F
^

1 error

Expected Behavior

Compile successfully.

Comment

Tested against 4-beta-1, 4-alpha-3, 3.0.9, and master (commit: b26dbbeabe1e3d27d30c936701b1a571e24d5ab2). Maybe similar to GROOVY-10254, but with parameterized class.