rewrite_python_shebang: move loop invariants out of loop

[bayandin]

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regex and maximum_regex_length variables do not change inside Pathname(".").find do |f| loop, so move them out of the loop.

brew style complains:

Library/Homebrew/language/python.rb:92:30: C: Do not compute the size of statically sized objects.
      maximum_regex_length = "#! /usr/bin/env pythonx.yyy$".length

Do I need to fix it something like this

-      maximum_regex_length = "#! /usr/bin/env pythonx.yyy$".length
+      maximum_regex_length = 28 # the lenght of "#! /usr/bin/env pythonx.yyy$"

Or add # rubocop:disable Performance/FixedSize
Or something else?

[iMichka]

Both are fine. I would go for maximum_regex_length = 28 # the lenght of "#! /usr/bin/env pythonx.yyy$" because I prefer not to carry on lint disabling lines around in my code.

[bayandin]

Thanks @iMichka, fixed now

[Bo98]

Tempting to not point out the series of Cmd+C and Cmd+V which has led the misspelling "lenght" to travel through the original post, into the comments and then the code.

[bayandin]

Tempting to not point out the series of Cmd+C and Cmd+V which has led the misspelling "lenght" to travel through the original post, into the comments and then the code.

And the lack of Cmd+C and Cmd+V when I wrote it initially 😄