Bug #17557: IRB array returned in multiple lines

• Status: Closed
• Assignee: -
• Target version: -
• ruby -v: ruby 2.7.0p0 (2019-12-25 revision 647ee6f091) [x86_64-linux]
• Backport: 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN, 3.0: UNKNOWN

[sergioro (Sergio Romero)]

Hi Rubysts. In previous versions of IRB an array was displayed in a single line like:

's'.methods
=> [:unicode_normalize, :unicode_normalize!, :ascii_only?, :to_r, :unpack, ..., :!=, :equal?, :__id__, :instance_eval, :instance_exec]

But in version 1.3.1 (2021-01-12) the array is returned in multiple lines:

's'.methods
=>
[:unicode_normalize,
 :unicode_normalize!,
 :ascii_only?,
 :to_r,
 :unpack,
 ...,
 :!=,
 :equal?,
 :__id__,
 :instance_eval,
 :instance_exec]

Is there a way to toggle this behavior, perhaps IRB.conf?

[k0kubun (Takashi Kokubun)]

• Status changed from Open to Closed

We changed the default IRB inspector from inspect-based one to pretty_inspect-based one, which prints a content in multiple lines when it exceeds 79 chars, for Ruby 3.1+ IRB.

Given that, we have two choices:

1. Use IRB.conf[:INSPECT_MODE] = :inspect in your ~/.irbrc. This makes the behavior compatible with Ruby 3.0 IRB, which, however, cannot syntax-highlight an inspect output of objects like Struct.
2. Dynamically change the threshold 79 using Reline's API in the new pp-based inspector. It would still print an array in a single line as long as it's not too large.

2 would be a valid feature request, but because my comment already addresses the ticket's concern, I'm closing this ticket.

[k0kubun (Takashi Kokubun)]

The point 2 was merged to IRB master https://github.com/ruby/irb/pull/174. It seems 's'.methods returns way more things than what's written in the description and thus it doesn't help your case though.

[sergioro (Sergio Romero)]

Thanks, (1) solved the issue.