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* [ruby-core:115023] [Ruby master Bug#19924] Character literal escaped \xFF stops parsing
@ 2023-10-12 15:50 kddnewton (Kevin Newton) via ruby-core
  2023-11-10  2:43 ` [ruby-core:115327] " nagachika (Tomoyuki Chikanaga) via ruby-core
  0 siblings, 1 reply; 2+ messages in thread
From: kddnewton (Kevin Newton) via ruby-core @ 2023-10-12 15:50 UTC (permalink / raw
  To: ruby-core; +Cc: kddnewton (Kevin Newton)

Issue #19924 has been reported by kddnewton (Kevin Newton).

----------------------------------------
Bug #19924: Character literal escaped \xFF stops parsing
https://bugs.ruby-lang.org/issues/19924

* Author: kddnewton (Kevin Newton)
* Status: Open
* Priority: Normal
* Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN
----------------------------------------
When you have a character literal, you can have an escaped character. For things that don't actually need escaping, this works out to just returning the character itself. For example:

``` ruby
?\d # => "d"
```

This works for every codepoint in ASCII-8bit _except_ 0xFF. When that byte is hit, the entire parser will stop parsing and just return `nil`.

``` ruby
eval(<<~RUBY)
  # encoding: ascii-8bit

  p ?\\\xFF

  puts "this will never be parsed"
RUBY
```

If you try to parse it with `RubyVM::AbstractSyntaxTree`, it's clear the parser just stops:

``` ruby
RubyVM::AbstractSyntaxTree.parse(<<~RUBY)
  # encoding: ascii-8bit

  p ?\\\xFF

  puts "this will never be parsed"
RUBY

# => (SCOPE@1:0-2:1 tbl: [] args: nil body: (VCALL@2:0-2:1 :p))
```



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^ permalink raw reply	[flat|nested] 2+ messages in thread

* [ruby-core:115327] [Ruby master Bug#19924] Character literal escaped \xFF stops parsing
  2023-10-12 15:50 [ruby-core:115023] [Ruby master Bug#19924] Character literal escaped \xFF stops parsing kddnewton (Kevin Newton) via ruby-core
@ 2023-11-10  2:43 ` nagachika (Tomoyuki Chikanaga) via ruby-core
  0 siblings, 0 replies; 2+ messages in thread
From: nagachika (Tomoyuki Chikanaga) via ruby-core @ 2023-11-10  2:43 UTC (permalink / raw
  To: ruby-core; +Cc: nagachika (Tomoyuki Chikanaga)

Issue #19924 has been updated by nagachika (Tomoyuki Chikanaga).

Backport changed from 3.0: REQUIRED, 3.1: REQUIRED, 3.2: REQUIRED to 3.0: REQUIRED, 3.1: REQUIRED, 3.2: DONE

ruby_3_2 482e1f573ee45ef562cc6d218ba26d44660f8e0a merged revision(s) 17b0643392749f45b7aacb64fc1c1bd704d42b4c.

----------------------------------------
Bug #19924: Character literal escaped \xFF stops parsing
https://bugs.ruby-lang.org/issues/19924#change-105247

* Author: kddnewton (Kevin Newton)
* Status: Closed
* Priority: Normal
* Backport: 3.0: REQUIRED, 3.1: REQUIRED, 3.2: DONE
----------------------------------------
When you have a character literal, you can have an escaped character. For things that don't actually need escaping, this works out to just returning the character itself. For example:

``` ruby
?\d # => "d"
```

This works for every codepoint in ASCII-8bit _except_ 0xFF. When that byte is hit, the entire parser will stop parsing and just return `nil`.

``` ruby
eval(<<~RUBY)
  # encoding: ascii-8bit

  p ?\\\xFF

  puts "this will never be parsed"
RUBY
```

If you try to parse it with `RubyVM::AbstractSyntaxTree`, it's clear the parser just stops:

``` ruby
RubyVM::AbstractSyntaxTree.parse(<<~RUBY)
  # encoding: ascii-8bit

  p ?\\\xFF

  puts "this will never be parsed"
RUBY

# => (SCOPE@1:0-2:1 tbl: [] args: nil body: (VCALL@2:0-2:1 :p))
```



-- 
https://bugs.ruby-lang.org/
 ______________________________________________
 ruby-core mailing list -- ruby-core@ml.ruby-lang.org
 To unsubscribe send an email to ruby-core-leave@ml.ruby-lang.org
 ruby-core info -- https://ml.ruby-lang.org/mailman3/postorius/lists/ruby-core.ml.ruby-lang.org/

^ permalink raw reply	[flat|nested] 2+ messages in thread

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