Another Style/FormatStringToken false positive

[mikegee]

Github didn't let @lionel218 open this issue for some reason. See the original report at #5245 (comment)

---

Expected behavior

no offense from Style/FormatStringToken

Actual behavior

% bundle exec bin/rubocop test/test.rb --only Style/FormatStringToken
Inspecting 1 file
C

Offenses:

test/test.rb:2:75: C: Style/FormatStringToken: Prefer annotated tokens (like %<foo>s) over unannotated tokens (like %s).
  format('%<day>s %<start>s-%<end>s', day: open_house.starts_at.strftime('%a'),
                                                                          ^^
test/test.rb:4:76: C: Style/FormatStringToken: Prefer annotated tokens (like %<foo>s) over unannotated tokens (like %s).
                                      end: open_house.ends_at.strftime('%l %p').strip)
                                                                           ^^

1 file inspected, 2 offenses detected

Steps to reproduce the problem

Use this file:

def event_date(open_house)
  format('%<day>s %<start>s-%<end>s', day: open_house.starts_at.strftime('%a'),
                                      start: open_house.starts_at.strftime('%l'),
                                      end: open_house.ends_at.strftime('%l %p').strip)
end

RuboCop version

$ rubocop -V
0.53.0 (using Parser 2.5.0.2, running on ruby 2.5.0 x86_64-darwin16)

[lionel218]

Hi @bbatsov, @koic , Did you solve this issue?

[katherine-boost]

Just upgraded to 0.75 and I'm seeing this error again. Anyone else?

[buehmann]

@katherine-boost I was working on this cop for the 0.75 release. What error exactly are you seeing?

[katherine-boost]

Thanks for your reply @buehmann

The error:

Style/FormatStringToken: Prefer annotated tokens (like %<foo>s) over unannotated tokens (like %s).

The line of code provoking the error:

formatted_cents = format('%02d', cents % 100)

[buehmann]

@katherine-boost That is not an error. The cop behaves as designed. With style annotated, which is the default, it suggests to use named format sequences and not positional ones. In your example:

formatted_cents = format('%02<remainder>d', remainder: cents % 100)

Also see https://docs.rubocop.org/en/stable/cops_style/#styleformatstringtoken

[ndbroadbent]

Hello, just wanted to post another issue in here. When I set this in my rubocop.yml to enforce the template style:

Style/FormatStringToken:
  EnforcedStyle: template

I'm getting this error:

C: Style/FormatStringToken: Prefer template tokens (like %{foo}) over annotated tokens (like %<foo>s).
  format('%<red>02x%<green>02x%<blue>02x', color_values)

I'm not sure if I am able to switch these to the template style, because I believe that is only for strings, while I need to use the %02x to get hex values.

[buehmann]

@ndbroadbent Good point. Would you mind creating a new issue for this? Template style has indeed no way I know to influence the type conversion. By the way, it seems to accept non-strings as an argument, but does not simply do to_s (e.g. for arrays).