[ruby-core:95155] [Ruby master Bug#16181] return from a proc in a module/class body returns out of script. Should be LJE.

[tom.enebo@gmail.com]

Issue #16181 has been updated by enebo (Thomas Enebo).


I agree this is impossible to be done by parser or at iseq generation time.   It must be done when return is invoked.

JRuby will return LocalJumpError for this for 9.2.9.0.  It also had from 9.2.6.0 and earlier.

As a runtime LJE we know lexically it is defined within a module/class and we can also look up stack to see if it has migrated or not (I assume MRI has even more flexibility in this than JRuby does). Similarly we know it is a lambda or not at that point so that is not really a problem at runtime.

Jeremy,  since you are only person who has looked would you say semantically this should be some error vs silently only executing part of a file?

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Bug #16181: return from a proc in a module/class body returns out of script.  Should be LJE.
https://bugs.ruby-lang.org/issues/16181#change-81795

* Author: enebo (Thomas Enebo)
* Status: Open
* Priority: Normal
* Assignee: 
* Target version: 
* ruby -v: 
* Backport: 2.5: UNKNOWN, 2.6: UNKNOWN
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return is not allowed from class/module body.  But if we insert a return into a block then we can invoke the block then it returns all the way out of the script.  This has to be accidental behavior doesn't it?  I believe the case below should end up as a LocalJumpError:


```
class Foo
  proc { return }.call
end
puts "NEVER SEEN"
```

This behavior started some time in 2.5 (it used to be an LJE).



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