[GROOVY-9006] Static type checking fails on java.sql.Timestamp when compared to null

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.5.15, 3.0.9
• Fix Version/s: 4.0.0-beta-2, 3.0.10, 2.5.17
• Component/s: Static Type Checker
• Assignee: Eric Milles
• Reporter: Devin Rosenbauer
• Created: 20/Feb/19 17:40
• Updated: 30/Apr/22 21:09
• Resolved: 23/Oct/21 17:01

Description

The following class fails when compiled by Groovy 2.5.6 (via Gradle). The error is:

src/main/groovy/Bug.groovy: 11: [Static type checking] - Reference to method is ambiguous. Cannot choose between [boolean java.sql.Timestamp#equals(java.sql.Timestamp), boolean java.sql.Timestamp#equals(java.lang.Object)]
 @ line 11, column 13.
           if (timestamp != null) {
               ^

Class code for Bug.groovy -

import groovy.transform.TypeChecked

import java.sql.Timestamp

@TypeChecked
class Bug {

    public void bug() {
        java.sql.Timestamp timestamp = new Timestamp(new Date().getTime());

        if (timestamp != null) {

        }
    }

}

Expected behavior: Groovy compiles "x != null" without reference to Java's equals.