[GROOVY-11121] unexpected error when having overloaded methods, one of which receiving an Iterable

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 5.0.0-alpha-5
• Component/s: Static Type Checker
• Labels: overloading

Language

groovy

• Assignee: Eric Milles
• Reporter: Thodoris Sotiropoulos
• Created: 09/Jul/23 12:59
• Updated: 05/Mar/24 01:53
• Resolved: 15/Jan/24 16:06

Description

I have the following program

import java.util.function.*;

class Foo<T> {
  static <T> Foo<T> of(Iterable<T> values) { return null; }
  static <T> Foo<T> of(T values) { return null; }
}

class Main {
  static final void test() {
    Foo.<IntUnaryOperator>of((int s) -> s + 1);
  }
}

Actual behavior

org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed:
Main.groovy: 10: [Static type checking] - Wrong number of parameters for method target: iterator()
 @ line 10, column 38.
       var x = Foo.<IntUnaryOperator>of((int s) -> s + 1);
                                        ^

1 error

Expected behavior

Compile successfully

Notes

Test case adapted from the following program that uses the apache-commons-io library:

import org.apache.commons.io.function.*;
import java.util.function.*;

class Main {
  static final void test() {
    var x = IOStream.<IntUnaryOperator>of((int s) -> s + 1);
  }
}

Issue Links

• is related to: GROOVY-7582 Closure to SAM coercion doesn't handle overloads with different SAM signatures
• is related to: GROOVY-9852 Result is already complete (IllegalStateException)
• is related to: GROOVY-9881 STC can't distinguish SAMs based on arity
• is related to: GROOVY-10905 Improve matching implicit arg closures to SAM types