Issue #21795 has been updated by kddnewton (Kevin Newton). @mame thanks for the great prototype. I think `#syntax_tree` makes a lot of sense, and I think the name and implementation are both fine. As a small note, I noticed that you manually implement the DFS to find the child node because you need access to the parent. Maybe `Node#find` should yield the parent as the second argument to the block? Or we could come up with another solution, like `Prism.parse(attach_parent:)` or something like that. Just a note for later. Regarding the warning, I share @Earlopain's concern that the warning isn't really actionable. I think I would personally prefer a comment indicating this isn't considered stable or that it's considered experimental. But I don't think that's a blocker for this getting merged. I also don't think this should necessarily expose RubyVM::AST. I think it would make more sense to return `nil` or raise an error in the case the ISEQ was compiled with the parse.y compiler. But I also don't think that's a blocker for this getting merged. Overall I'm positive on this. 👍 ---------------------------------------- Feature #21795: Methods for retrieving ASTs https://bugs.ruby-lang.org/issues/21795#change-118330 * Author: kddnewton (Kevin Newton) * Status: Open ---------------------------------------- I would like to propose a handful of methods for retrieving ASTs from various objects that correspond to locations in code. This includes: * Proc#ast * Method#ast * UnboundMethod#ast * Thread::Backtrace::Location#ast * TracePoint#ast (on call/return events) The purpose of this is to make tooling easier to write and maintain. Specifically, this would be able to be used in irb, power_assert, error_highlight, and various other tools both in core and not that make use of source code. There have been many previous discussions of retrieving node_id, source_location, source, etc. All of these use cases are covered by returning the AST for some entity. In this case node_id becomes an implementation detail, invisible to the user. Source location can be derived from the information on the AST itself. Similarly, source can be derived from the AST. Internally, I do not think we have to store any more information than we already do (since we have node_id for the first four of these, it becomes rather trivial). For TracePoint we can have a larger discussion about it, but I think it should not be too much work. In terms of implementation, the only caveat I would put is that if the ISEQ were compiled through the old parser/compiler, this should return `nil`, as the node ids do not match up and we do not want to further propagate the RubyVM::AST API. The reason I am opening up this ticket with 5 different methods requested in it is to get approval first for the direction, then I can open individual tickets or just PRs for each method. I believe this feature would ease the maintenance burden of many core libraries, and unify otherwise disparate efforts to achieve the same thing. -- https://bugs.ruby-lang.org/