[GROOVY-8892] Trait instance init blocks are called only when there are fields defined in same Trait

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.5.5
• Fix Version/s: 3.0.0-alpha-4, 2.5.5
• Component/s: Compiler, groovy-runtime
• Assignee: Paul King
• Reporter: Anton Pryamostanov
• Created: 18/Nov/18 18:20
• Updated: 16/Jan/19 12:07
• Resolved: 19/Nov/18 03:53

Description

With ref. to GROOVY-8880, it seems Instance Init Blocks in Traits are appended/called only when there are fields defined in the same trait.

Example:

trait TraitOne {
    {
        System.out.println("Does not work")
    }
}
trait TraitTwo {
    Integer instanceCounter //immutable, non-shareable
    {
        System.out.println("Works")
        instanceCounter = 1
    }
}
class ClassWithTrait implements TraitOne, TraitTwo {
}
new ClassWithTrait().instanceCounter

Output:

Works

Expected output (order may differ):

Works
Does not work

Issue Links

• relates to: GROOVY-8891 Trait Instance Init Block causes Runtime exception for Trait fields with default values
• relates to: GROOVY-8880 Traits - static/instance init blocks