Refactor CrystalPath::Error #9359
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Introduces a dedicated error type for path lookup fails which contains information about the path being looked up. This separates creating the actual compiler error which then happens in SemanticVisitor#visit(Require).
| @@ -68,6 +68,24 @@ abstract class Crystal::SemanticVisitor < Crystal::Visitor | |||
| node.expanded = expanded | |||
| node.bind_to(expanded) | |||
| false | |||
| rescue ex : CrystalPath::NotFoundError | |||
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Can we move this rescue just around find_in_path because that's where the error can happen? This makes it much clearer when the exception is expected to happen.
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I considered that, but the problem is that the exception raised there would subsequently be rescued in line 89. I don't think it makes sense to make that rescue handler work around that.
A slightly less confusing option could be to create the error in a rescue around find_in_path, assign it to a local variable and only raise in an else rescue handler. Not sure if that's worth it, though.
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Oh, I see. Yeah, let's leave it like that for now.
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That said, I don't understand why CrystalPath::NotFoundError is handled in a special way here, instead of just being a regular Crystal::Exception and having a sensible to_s.
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The idea was to have CrystalPath::NotFoundError as a plain internal error type, not related to any user code interpretation. CrystalPath should not care wheter it was invoked for a require or something else. It also doesn't know the code location, so it can't really create a proper user-facing error.
NotFoundError just communicates that finding a path failed. What that means depends on the context. In the context of interpreting a Require node it means the require has failed and an appropriate error is raised for that specific situation.
Introduces a dedicated error type
CrystalPath::NotFoundErrorfor path lookup fails which contains information about the path being looked up.This separates creating the actual compiler error which then happens in
SemanticVisitor#visit(Require).Also refactors the specs to not use absolute paths which could compromise the spec effectiveness.
This PR is part of a series on refactoring compiler errors #8410 (comment)