0.41.1: Style/EachForSimpleLoop autocorrection calculates wrong number of repetitions

[dabroz]

Style/EachForSimpleLoop autocorrection calculates wrong number of repetitions.

Test case

(1..5).each { print '+' } # result: +++++

Expected behavior

5.times { print '+' } # result: +++++

Actual behavior

4.times { print '+' } # result: ++++

Steps to reproduce the problem

1. Put test case in a test.rb file
2. Run rubocop -a

RuboCop version

0.41.1 (using Parser 2.3.1.2, running on ruby 2.3.1 x86_64-darwin14)

[Aqualon]

This was not completely fixed by #3221, the code https://github.com/bbatsov/rubocop/blob/e2af464b809180ae2de1785c362c25291995e586/lib/rubocop/cop/style/each_for_simple_loop.rb#L38 finds irange and erange type of ranges, but the max - min computation only works for erange.

[Drenmi]

This is pretty bad actually. All the unit tests are incorrect. Example:

corrected = autocorrect_source(cop, '(0..10).each {}')
expect(corrected).to eq '10.times {}'

But (0..10) is an inclusive range of 0 through 10, i.e. 11 iterations. This is repeated throughout the suite. There are no test cases for exclusive ranges.