[GROOVY-10407] unchecked method invocation warning in generated stubs

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 3.0.9
• Fix Version/s: 3.0.10, 4.0.0-rc-2, 2.5.21
• Component/s: Compiler
• Assignee: Eric Milles
• Reporter: Joseph Price
• Created: 08/Dec/21 04:22
• Updated: 18/Jan/23 00:03
• Resolved: 12/Dec/21 19:10

Description

 

When calling a groovy class from java that takes a Map in the constructor, the generated stubs have what looks to be a second constructor that takes a null for the parameter, that casted to a raw Map. Since this happens in generated code not under my control, this prevents enabling -Werror across the project. Providing type arguments for the map or leaving the cast off would fix the warning, but I also wonder if suppressing the constructor is possible.

Below are the commands I ran, along with the contents of the java and groovy files:

groovyc -j  -FWerror -FXlint:unchecked Test.java Base.groovy
org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed:
Compile error during compilation with javac.
/var/folders/mm/8s324dkd6sb1ktx0g48pbvhc0000gq/T/groovy-generated--java-source3303303787390544788/Base.java:13: warning: [unchecked] unchecked method invocation: constructor <init> in class Parent is applied to given types
super ((java.util.Map)null);
      ^
  required: Map<String,String>
  found: Map
/var/folders/mm/8s324dkd6sb1ktx0g48pbvhc0000gq/T/groovy-generated--java-source3303303787390544788/Base.java:13: warning: [unchecked] unchecked conversion
super ((java.util.Map)null);
       ^
  required: Map<String,String>
  found:    Map
error: warnings found and -Werror specified
1 error
2 warnings                                                                      

 

cat -p Base.groovy

class Parent {
  Parent(Map<String, String> map) {
  }
}

class Base extends Parent {
  Base(Map<String, String> map) {
    super(map);
  }
}                                                                               

cat -p Test.java

import java.util.Map;
class Test {
  Base b = new Base(Map.of());
}