Feature #20275
Updated by Eregon (Benoit Daloze) 3 months ago
From https://bugs.ruby-lang.org/issues/19117#note-48:
```ruby
def raise_nested_exceptions
raise "First error"
rescue
begin
raise "Second error"
rescue
raise "Third error"
end
end
raise_nested_exceptions
```
Current:
```
-:7:in 'Object#raise_nested_exceptions': Third error (RuntimeError)
from -:4:in 'Object#raise_nested_exceptions'
from -:1:in 'Object#raise_nested_exceptions'
from -:11:in '<main>'
-:5:in 'Object#raise_nested_exceptions': Second error (RuntimeError)
from -:1:in 'Object#raise_nested_exceptions'
from -:11:in '<main>'
-:2:in 'Object#raise_nested_exceptions': First error (RuntimeError)
from -:11:in '<main>'
```
The above repeated backtrace entries for `Object#raise_nested_exceptions` are because of CRuby implementation details.
It seems best to hide them because they do not help understanding the program, and semantically there is no (method or proc) call on line 1 or 4.
Proposed:
```
-:7:in 'Object#raise_nested_exceptions': Third error (RuntimeError)
from -:11:in '<main>'
-:5:in 'Object#raise_nested_exceptions': Second error (RuntimeError)
from -:11:in '<main>'
-:2:in 'Object#raise_nested_exceptions': First error (RuntimeError)
from -:11:in '<main>'
```
We can see TruffleRuby and JRuby already behave this way, most likely because they do not use an extra frame for `rescue`.
It is definitely useful to have the same backtrace on different Ruby implementations as some tests rely on this.
TruffleRuby 23.1.2:
```
-:7:in `raise_nested_exceptions': Third error (RuntimeError)
from -:11:in `<main>'
-:5:in `raise_nested_exceptions': Second error (RuntimeError)
from -:11:in `<main>'
-:2:in `raise_nested_exceptions': First error (RuntimeError)
from -:11:in `<main>'
```
JRuby 9.4.5.0:
```
RuntimeError: Third error
raise_nested_exceptions at -:7
<main> at -:11
RuntimeError: Second error
raise_nested_exceptions at -:5
<main> at -:11
RuntimeError: First error
raise_nested_exceptions at -:2
<main> at -:11
```