[GROOVY-8150] Inconsistency in multiple assignment with single variable

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.5.0-alpha-1, 2.4.10
• Fix Version/s: 2.6.0-alpha-1
• Assignee: Daniel Sun
• Reporter: Daniil Ovchinnikov
• Created: 07/Apr/17 16:24
• Updated: 06/Mar/18 23:25
• Resolved: 02/May/17 02:12

Description

def a
def b = [1]

a = b
println "${a} : ${a.class}" // [1] : class java.util.ArrayList
(a) = b
println "${a} : ${a.class}" // 1 : class java.lang.Integer
((a)) = b
println "${a} : ${a.class}" // [1] : class java.util.ArrayList

This is confusing. Here are options:
1. ((a)) = b should be failed to parse.
2. ((a)) = b should behave like (a) = b, i.e. number of parentheses should not matter.
3. ((a)) = b and (a) = b should behave like a = b. This will match the following case also:

class A { def myField }

def a = new A()
def b = [1]

a.myField = b
assert a.myField == [1]

(a.myField) = b
assert a.myField == [1]

((a.myField)) = b
assert a.myField == [1]