[GROOVY-7141] Static type checker does not recognize closure input parameter when implementing an interface with a map

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.3.7
• Fix Version/s: 3.0.14, 2.5.20, 4.0.7
• Component/s: Static Type Checker
• Assignee: Eric Milles
• Reporter: Mauro Molinari
• Created: 29/Oct/14 10:46
• Updated: 10/Feb/23 21:40
• Resolved: 01/Nov/22 16:34

Description

Consider the following Groovy class:

package e
import groovy.transform.TypeChecked;

@TypeChecked
class E {
	
	interface MyInt {
		String doSomething(String text)
	}
	
	static void main(String[] args) {
		MyInt impl = [
			doSomething: { it.toUpperCase() }
			] as MyInt
		println impl.doSomething('foo')
	}
}

The compiler complains that:

Groovy:[Static type checking] - Cannot find matching method java.lang.Object#toUpperCase(). Please check if 
 the declared type is right and if the method exists.

However I think Groovy should be smart enough to recognize that it is of type String inside the closure.