[ruby-core:116340] [Ruby master Feature#19117] Include the method owner in backtraces, not just the method name

["byroot (Jean Boussier) via ruby-core" <ruby-core@ml.ruby-lang.org>]

Issue #19117 has been updated by byroot (Jean Boussier).


>  That's just how Ruby code is written nowadays.

It's a common pattern for classes that are long enough, but it's also very common to cram multiple smaller classes in the same file, or multiple classes that are alternative implementations of the same interface.

The pattern is very common in Rails project because the autoloader forces you into a convention, but in gems or non-rails projects, anything goes.

And even in Rails projects, it's common not to extra small sub constants in their own file:

```ruby
# user.rb
class User
  class Permission
    # a dozen lines, not worth creating `user/permission.rb`
  end
end
```

And that also include numerous methods from the Ruby standard libraries, e.g.: `shellwords`

```
>> foo.shelljoin(1)
/Users/byroot/.rbenv/versions/3.3.0/lib/ruby/3.3.0/shellwords.rb:239:in `shelljoin': wrong number of arguments (given 1, expected 0) (ArgumentError)
```

Good luck guessing what `shelljoin` was called on.

With this patch it would be:

```
>> foo.shelljoin(1)
/Users/byroot/.rbenv/versions/3.3.0/lib/ruby/3.3.0/shellwords.rb:239:in `Array#shelljoin': wrong number of arguments (given 1, expected 0) (ArgumentError)
```

In other words, the `Class#method` pattern make it super easy to lookup the documentation, the path and line number, not so much. Personally I spend half my time opening the source of my dependencies, but for less confirmed users, opening the stdlib to read the source isn't a nice value proposition.


----------------------------------------
Feature #19117: Include the method owner in backtraces, not just the method name
https://bugs.ruby-lang.org/issues/19117#change-106365

* Author: byroot (Jean Boussier)
* Status: Open
* Priority: Normal
* Target version: 3.4
----------------------------------------
```
module Foo
  class Bar
    def inspect
      1 + '1'
    end
  end
end

p Foo::Bar.new
```

This code produce the following backtrace:


```
/tmp/foo.rb:4:in `+': String can't be coerced into Integer (TypeError)
	from /tmp/foo.rb:4:in `inspect'
	from /tmp/foo.rb:9:in `p'
	from /tmp/foo.rb:9:in `<main>'
```

This works, but on large codebases and large backtraces the method name isn't always all that revealing, most of the time you need to open many of the locations listed in the backtrace to really understand what is going on.

I propose that we also include the owner name:

```
/tmp/foo.rb:4:in `Integer#+': String can't be coerced into Integer (TypeError)
	from /tmp/foo.rb:4:in `Foo::Bar#inspect'
	from /tmp/foo.rb:9:in `Kernel#p'
	from /tmp/foo.rb:9:in `<main>'
```

I believe that in many case it would allow to much better understand the backtrace without having to jump back and forth between it and the source code.

This is inspired by @ivoanjo 's `backtracie` gem: https://github.com/ivoanjo/backtracie



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