Our ast.parse doesn't include a mode argument, could you maybe modify builtin_compile to accept PyCF_ONLY_AST? You could match on the mode and use rustpython_parser::parser::parse_program for exec and single or rustpython_parser::parser::parse_expression for eval. Maybe also enable builtin_compile even when the feature is off but just throw a runtime error if the caller doesn't pass PyCF_ONLY_AST so that ast.parse still works.

I would like to add the mode optional argument to the rust parse function. Note that the mode can be retrieve because mode implements FromStr now. Please refer to the builtin compile function how this is done.

I'm not too sure that this Mode enum should be contained in the parser crate. I feel it has its place in the compiler crate (where it was). The new parse function can be place in near the compile function in the builtins.rs in the vm crate.

Rationale: the mode is really a compiler thing. The parser should not be aware of the concept of mode, only parse code.

It seems Mode should be defined out of compile.rs because ast.parse works without #[cfg(feature = "rustpython-compiler")]. Any idea?

@windelbouwman any advice for proper place about this?

ast.parse should not work without the compiler crate, since when you have the compiler crate, the parser crate is implied. Vice versa is not true, but I think it makes sense to excluse ast.parse when the compiler feature is disabled. So I think we should place Mode in mode.rs in the rustpython-compiler crate.

I suggest to move this function to the builtins.rs in the vm crate.

Or maybe util.rs?

Yes, agreed, but in any case, this function should reside in the vm crate, since it uses a compilation mode.