Add new Lint/ScriptPermission cop

[yhirano55]

This cop checks if a file which has a shebang line as
its first line is granted execute permission.

---

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• Added tests.
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[bbatsov]

I'd use some more generic wording here - after all some people use Windows. ;-)

[bbatsov]

This should be extended a bit - after all the cop applies just scripts. Frankly, from this description people looking the manual would be quite confused.

[bbatsov]

This cop should certain check that the script files actually have shebang in them. Right now this is going to ignore every scripts that's not in bin/ and exe/ and that sucks.

Guess some logic can be used from other cops that we have which are dealing with shebangs.

[yhirano55]

@bbatsov Thanks for your code-review! I have addressed your feedbacks. Please review this codes, if you have a chance :)

[bbatsov]

Maybe we should mention the file name here, as this wording might convince some people. I'd also use working like Script file X doesn't have execute permission. (or something similar).

[yhirano55]

Oh, I see. I'll fix it. Thanks!!

[bbatsov]

Please, update the specs to use the new rspec helpers recently added by @backus.

[backus]

This should probably go under the Lint department. Doesn't seem like style

[yhirano55]

@bbatsov @backus Thanks for your comments. I've done:

• Used new rspec helpers.
• Changed department from Style to Lint.

[zavan]

I'm having a problem with this cop, it says my bin/update file doesn't have execute permissions, but it does.

I have tried chmod +x bin/update to no effect, here's my ls -laH output:

zavan@zavan-pc:~/projects/ruby/alm$ ls -laH bin/
total 92
drwxr-xr-x  2 zavan zavan 4096 mai 30 14:12 .
drwxr-xr-x 16 zavan zavan 4096 mai 30 13:54 ..
-rwxr-xr-x  1 zavan zavan  129 fev 24 20:41 bundle
-rwxr-xr-x  1 zavan zavan  180 jan 30 00:34 delayed_job
-rwxr-xr-x  1 zavan zavan  141 mai 22 23:46 rails
-rwxr-xr-x  1 zavan zavan   90 mai 22 23:46 rake
-rwxr-xr-x  1 zavan zavan  376 jan 30 00:34 rspec
-rwxr-xr-x  1 zavan zavan  920 fev 24 22:03 setup
-rwxr-xr-x  1 zavan zavan  782 mai 30 14:12 update

Notice that all files have the same permissions, but only this one is erroring out.

File::Stat#executable? returns true:

[13] pry(main)> >> File.new('/home/zavan/projects/ruby/alm/bin/update').stat.executable?
=> true

I have checked and the first line is #!/usr/bin/env ruby, here's the full source code:

#!/usr/bin/env ruby
require 'pathname'
require 'fileutils'
include FileUtils

# path to your application root.
APP_ROOT = Pathname.new File.expand_path('../../', __FILE__)

def system!(*args)
  system(*args) || abort("\n== Command #{args} failed ==")
end

chdir APP_ROOT do
  # This script is a way to update your development environment automatically.
  # Add necessary update steps to this file.

  puts '== Installing dependencies =='
  system! 'gem install bundler --conservative'
  system('bundle check') || system!('bundle install')

  puts "\n== Updating database =="
  system! 'bin/rails db:migrate'

  puts "\n== Removing old logs and tempfiles =="
  system! 'bin/rails log:clear tmp:clear'

  puts "\n== Restarting application server =="
  system! 'bin/rails restart'
end

I have also tried deleting and recreating the file and rewriting the shebang line.

Also, whatever happened to #3659? I agree that this is out of scope.

[sonalkr132]

@zavan I think the buffer/cache might be causing the problem. In my case, the cop complained correctly that a script file wasn't executable and it didn't shut up until I changed content of the file (add/delete an empty line)