Use relative path for offense message in Lint/DuplicateMethods

[pocke]

Currently Lint/DuplicateMethods cop messages have absolute paths.

$ rubocop test.rb --only Lint/DuplicateMethods
Inspecting 1 file
W

Offenses:

test.rb:3:1: W: Method Object#foo is defined at both /home/pocke/ghq/github.com/bbatsov/rubocop/test.rb:1 and /home/pocke/ghq/github.com/bbatsov/rubocop/test.rb:3.
def foo
^^^

1 file inspected, 1 offense detected

I think Absolute path is unnecessarily long.
And we use relative path for a location of an offense(e.g. test.rb:3:1).
So, I think we should use relative path for this message also.

By this change, the absolute path is replaced with relative path.

For example:

$ rubocop test.rb --only Lint/DuplicateMethods
Inspecting 1 file
W

Offenses:

test.rb:3:1: W: Method Object#foo is defined at both test.rb:1 and test.rb:3.
def foo
^^^

1 file inspected, 1 offense detected

What do you think?

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[rrosenblum]

Makes sense to me. Should there be a test that shows off this functionality?

[bbatsov]

Ideally, yes. And we should check whether other cops aren't using absolute paths for consistency's sake.

[pocke]

I've added tests, and changed to use smart_path method. The method changes path to relative only if file is in project root.

Should there be a test that shows off this functionality?

Thanks for your suggestion. I've added tests.

And we should check whether other cops aren't using absolute paths for consistency's sake.

$ git grep buffer.name
lib/rubocop/comment_config.rb:      Cop::Cop.qualified_cop_name(cop_name.strip, processed_source.buffer.name)
lib/rubocop/cop/commissioner.rb:        remove_irrelevant_cops(processed_source.buffer.name)
lib/rubocop/cop/layout/leading_comment_space.rb:                    config_ru?(processed_source.buffer.name)
lib/rubocop/cop/lint/duplicate_methods.rb:          path = smart_path(range.source_buffer.name)
lib/rubocop/cop/style/file_name.rb:          file_path = processed_source.buffer.name
lib/rubocop/cop/team.rb:          filename = buffer.name
lib/rubocop/processed_source.rb:      buffer_name = @path || STRING_SOURCE_NAME
lib/rubocop/processed_source.rb:      @buffer = Parser::Source::Buffer.new(buffer_name, 1)

Style/FileName cop uses buffer.name, but the cop uses relative paths for messages.
So, I guess cops that use absolute paths for messages doesn't exist.

[bbatsov]

👍