[GROOVY-5872] null initial value can't be inferred with generic field of a class

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.1.0-beta-1
• Fix Version/s: 2.1.0-rc-1, 2.0.7
• Component/s: Static Type Checker
• Assignee: Cédric Champeau
• Reporter: UEHARA Junji
• Created: 02/Jan/13 02:12
• Updated: 19/Jan/16 18:10
• Resolved: 07/Jan/13 06:22

Description

In following code, I expect no STC error at (A).

import groovy.transform.*
@TypeChecked // or @CompileStatic
class ccc {
  List<String> list = null // (A)
  List list2 = null // OK
  String str = null // OK
  public static void main(String [] args) {
    List<String> list = null // OK
  }
}

but compiler says:

org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed:
/Users/uehaj/work/201301/gastha_magazine/ccc.groovy: 4: [Static type checking] - Incompatible generic argument types. Cannot assign java.lang.Object to: java.util.List <String>
@ line 4, column 23.
List<String> list = null
^

1 error

Of course I can avoid this error by modify the code to:

     List<String> list = (List<String>)null