Bug #2551: case/when matches literal *[1,2,3] but not variable *ary

• Status: Closed
• Assignee: -
• Target version: Ruby 1.8.8
• ruby -v: ruby 1.8.8dev (2010-01-01 revision 26212) [i386-darwin10.2.0]

[bitsweat (Jeremy Daer)]

=begin
Matching a splat works with a literal but not a variable:

$ irb188

case 42; when *[41..43]; true end
=> true
a = [41..43]
=> [41..43]
case 42; when *a; true end
=> nil

Behaves correctly on 1.9.2dev and 1.8.7:

$ irb192

RUBY_DESCRIPTION
=> "ruby 1.9.2dev (2010-01-03 trunk 26233) [x86_64-darwin10.2.0]"
case 42; when *[41..43]; true end
=> true
a = [41..43]
=> [41..43]
case 42; when *a; true end
=> true

This breaks a lot of code, such as the Builder library which escapes all values as '***' on 1.8.8dev.

A test case:

diff --git a/test/ruby/test_case.rb b/test/ruby/test_case.rb
index af925d1..f996ed6 100644
--- a/test/ruby/test_case.rb
+++ b/test/ruby/test_case.rb
@@ -52,5 +52,13 @@ class TestCase < Test::Unit::TestCase
else
assert(false)
end
+

• range = [41..43]
• case 42
• when *range

•  assert(true)
  

• else

•  assert(false)
  

• end
  end
  end
  =end

[bitsweat (Jeremy Daer)]

=begin
Duplicates #2468.
=end

[bitsweat (Jeremy Daer)]

=begin
This is a show-stopper bug that affects a lot of my code. If it's not going to be fixed, perhaps the 19migration/looser_args merge should be reverted.
=end

[knu (Akinori MUSHA)]

• Status changed from Open to Closed

=begin
This issue was solved with changeset r26589.
Romulo, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.

=end

[bitsweat (Jeremy Daer)]

=begin
r26589 adds a failing test case but no fix. Please reopen.
=end

[marcandre (Marc-Andre Lafortune)]

• Status changed from Closed to Open

=begin

=end

[naruse (Yui NARUSE)]

• Status changed from Open to Closed

=begin

I wish "ref [Bug #...]" would have been parsed just like "cf: [Bug #...]".
#... may change when the ticket moves from bug to backport or something.
So writing ref #... is correct.
=end