Variable assignment to self

[cswoods6]

I was in the situation of replacing multiple method calls with variables and accidentally assigned the variable to itself without any modification. Would these be a useful smell to add?

Example: foo = foo

[troessner]

I think it would be a nice addition - @mvz wdyt?

@cswoods6 if you want to come up with a PR we could certainly guide you towards the goal ;)

[mvz]

Ah yes, I was still going to find out what that code does if this is the first time foo is assigned, and there's a method called foo as well.

It does look weird though so should definitely be caught by either Reek or RuboCop.

[JuanVqz]

should it detect any local variable + method with the same name? even foo = foo is going to be invalid?

[troessner]

So in my mind foo = foo should be a smell regardless if the right hand foo is the same variable or a method. If the right hand foo is a variable its obviously wrong and if its a method then its confusing, particularly if used without the parentheses. If its about saving additional method calls then the left-hand foo should be named differently or it might be smarter to memoize that function call so subsequent calls are "for free".

[mvz]

I just tested this, and this assigns the method result to the variable:

foo = foo()

while this does not and leaves foo nil:

foo = foo

So, I agree the second form is bad and so does RuboCop.

I'm not sure this is really a code smell though? Maybe this should be left to RuboCop instead?