[ruby-core:109929] [Ruby master Bug#19006] Inconsistent behaviour of autoload in wrapped script

["jeremyevans0 (Jeremy Evans)" <noreply@ruby-lang.org>]

Issue #19006 has been updated by jeremyevans0 (Jeremy Evans).


When loading `foo.rb` with the `MyModule` wrapper, you are loading the equivalent of:

```ruby
module MyModule
  module Foo
    autoload :Bar, "foo/bar"
  end
end
```

`foo/bar.rb` defines `::Foo::Bar`, not `::MyModule::Foo::Bar`, so I think the error you receive when you attempt to load `MyModule::Foo::Bar` is expected.

`load`'s wrapped module is not transitive to `load`/`require`/`autoload` calls inside the loaded file.  It was never designed to be transitive, nor documented as being transitive, so I don't think the current behavior is a bug.  Making the behavior transitive would be a feature request, IMO.

FWIW, I agree that the lack of transitivity makes `load`'s wrapped module not very useful in practice.  However, I don't see that as a problem.

----------------------------------------
Bug #19006: Inconsistent behaviour of autoload in wrapped script
https://bugs.ruby-lang.org/issues/19006#change-99177

* Author: shioyama (Chris Salzberg)
* Status: Open
* Priority: Normal
* Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN
----------------------------------------
Suppose I have two files, `foo.rb` and `bar.rb`:

```ruby
# foo.rb

puts "loading Foo..."

module Foo
  autoload :Bar, "foo/bar"
end
```

and

```ruby
# foo/bar.rb

puts "loading Foo::Bar..."

module Foo
  module Bar
  end
end
```

I can `require "foo"` and access both `Foo` and `Foo::Bar`:

```ruby
require "foo"
# loading Foo...
#=> true
Foo::Bar
# loading Foo::Bar...
#=> Foo::Bar
```

However, if I _load_ `foo` under a wrap module with `load`:

```ruby
MyModule = Module.new
load "./foo.rb", MyModule
# loading Foo...
#=> true
```

... I'm now unable to access `Foo::Bar` anywhere, because whereas the constant is autoloaded from `MyModule::Foo::Bar`, it is required from the top-level as `Foo::Bar`:

```ruby
MyModule::Foo::Bar
# loading Foo::Bar
#=> uninitialized constant MyModule::Foo::Bar (NameError)
```

This means that `autoload` is basically useless inside anything loaded with the `wrap` argument to `load`, because the file being autoloaded can't know in advance what the base namespace will be.

I would argue that it makes much more sense to apply the wrap module (`top_wrapper`) to any autoloaded file loaded when `top_wrapper` is set. In the example above, this would mean that accessing `MyModule::Foo::Bar` would work, since `MyModule` would apply when the autoload triggers to load `foo/bar`.



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