From: "yahonda (Yasuo Honda) via ruby-core" <ruby-core@...>
Date: 2024-10-26T03:47:48+00:00
Subject: [ruby-core:119624] [Ruby master Bug#20817] Ruby 3.4.0dev emits `warning: possibly useless use of + in void context` while Ruby 3.3.5 does not
Issue #20817 has been updated by yahonda (Yasuo Honda).
Using parse.y parser works as Ruby 3.3.5 does. No warnings emitted.
```
$ RUBYOPT=--parser=parse.y ruby -v
ruby 3.4.0dev (2024-10-25T11:52:32Z master 9c8c140d73) [x86_64-linux]
$ RUBYOPT=--parser=parse.y ruby -w foo.rb
lib/file.rb:42:in 'Kernel#eval': (eval at lib/file.rb:42):2: syntax error, unexpected string literal, expecting 'do' or '{' or '(' (SyntaxError)
'abc' + pluralize 'def'
^
from lib/file.rb:42:in 'C#throw_syntax_error'
from foo.rb:7:in '<main>'
$
```
----------------------------------------
Bug #20817: Ruby 3.4.0dev emits `warning: possibly useless use of + in void context` while Ruby 3.3.5 does not
https://bugs.ruby-lang.org/issues/20817#change-110244
* Author: yahonda (Yasuo Honda)
* Status: Open
* ruby -v: ruby 3.4.0dev (2024-10-25T11:52:32Z master 9c8c140d73) +PRISM [x86_64-linux]
* Backport: 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN
----------------------------------------
Ruby 3.4.0dev emits `warning: possibly useless use of + in void context` while Ruby 3.3.5 does not
This issue is based on Rails Action Pack test case against Ruby 3.4.0dev.
Here is the minimum script to reproduce it.
### Steps to reproduce
- Create a sample foo.rb file
```
class C
class_eval "def throw_syntax_error; eval %(
'abc' + pluralize 'def'
); end", "lib/file.rb", 42
end
c = C.new
c.throw_syntax_error
```
- Run this foo.rb using Ruby 3.4.0dev
### Expected behavior
It should report SyntaxError, but it shoud not emit any warnings as Ruby 3.3.5 does not.
```
$ ruby -v
ruby 3.3.5 (2024-09-03 revision ef084cc8f4) [x86_64-linux]
$ ruby -w foo.rb
lib/file.rb:42:in `eval': (eval at lib/file.rb:42):2: syntax error, unexpected string literal, expecting `do' or '{' or '(' (SyntaxError)
'abc' + pluralize 'def'
^
from lib/file.rb:42:in `throw_syntax_error'
from foo.rb:7:in `<main>'
```
### Actual behavior
It reports It should SyntaxError and it emits the `warning: possibly useless use of + in void context`
```
$ ruby -v
ruby 3.4.0dev (2024-10-25T11:52:32Z master 9c8c140d73) +PRISM [x86_64-linux]
$ ruby -w foo.rb
(eval at lib/file.rb:42):2: warning: possibly useless use of + in void context
lib/file.rb:42:in 'Kernel#eval': (eval at lib/file.rb:42):2: syntax error found (SyntaxError)
1 |
> 2 | 'abc' + pluralize 'def'
| ^ unexpected string literal, expecting end-of-input
3 |
from lib/file.rb:42:in 'C#throw_syntax_error'
from foo.rb:7:in '<main>'
$
```
--
https://bugs.ruby-lang.org/
______________________________________________
ruby-core mailing list -- ruby-core@ml.ruby-lang.org
To unsubscribe send an email to ruby-core-leave@ml.ruby-lang.org
ruby-core info -- https://ml.ruby-lang.org/mailman3/lists/ruby-core.ml.ruby-lang.org/