Recommended autocomplete for developing extensions?

I have started dabbling developing some extensions of my own, and have noticed that autocomplete is a bit lackluster for extension development. Are there any recommended extensions to install to aid in nova extension development?


Plugging my own extensions, which I created for this reason:

  • Install the TypeScript extension and install the @types/nova-editor or @types/nova-editor-node (more info) npm package in your workspace to get JavaScript or TypeScript autocompletion and validation for the Nova JS api.
  • Install the JSON extension to get autocompletion, validation, and hover-help within the extension.json file.

I can only heartily recommend Cameron’s extensions; they have been a mainstay of my own work on Nova extensions. Unluckily, there is no equivalent (I am aware of) for the XML side of things; having just about finished slogging my way though 3100 lines of syntax definition, I can tell you that would have been more than welcome.


I can only echo @kopischke@apexskier’s extensions are the de facto ‘gold standard’ for writing language-related extensions. They are quite extensive and use all kinds of tricks, sometimes not in a very obvious way, and additionally, they even incorporate some open-source Microsoft code which is also useful for a lot of functionality. From what I’ve been seeing on other extensions so far, @apexskier’s extensions are sort of a meta-template (a framework?) for pretty much everything related to language extensions…

@kopischke I’m going to be a fanatic user of your XML extension :rofl: Looking forward to it! The current alternatives (including Nova’s built-in one) are really limited, especially when it comes to validating XML; I’m not a VS Code user, but I’d love to have something like this in Nova, instead of manually copying and pasting XML to some online validation tool


(:eyes: and a schema with if someone wants to attempt it, should work like my json extension. Just throwing it out there!)

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I’m terribly sorry if my answer sounded as if I was developing a new syntax mode for XML; what I am actually developing is a syntax mode for fish shell scripting, which is done in XML. Not that I haven’t, in the months of wrestling with Nova’s rather basic XML support, wished for a better XML extension, but I have resisted the urge to bikeshed until now.

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I’ll admit I had a peek at lemminx while pondering the eternal “to bikeshed or not to bikeshed” question, but one of the issues I could see coming up is that there is no central repository of XML definitions one could use for Panic’s formats. SGML and its descendant XML have always expected the definers of their formats to provide a canonical link to, originally, a DTD (yes, I’m old enough to actually remember those, from my hardcover copy of the original SGML standard, no less :sweat_smile:), a Relax NG schema or an XML “capital s” Schema, so, unless I am entirely mistaken, not only would you have to define the bloody thing, you would also have to host it.


Interesting. My json extension doesn’t rely on a central repository, but defines the schema locally and registers it internally. The update cycle on a centralized repository can be painful (see the DefinitelyTyped definitions which I went a different route with) and I figured the overlap of people writing nova extension manifests who don’t have access to the nova extension to be pretty small.

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I figured the overlap of people writing nova extension manifests who don’t have access to the nova extension to be pretty small.

You are right, of course, but baking in support for Nova specific formats into a generic XML extension seems, to me at least, at odds with separation of concerns. I find this less concerning with JSON, which has no canonical way of supporting definition files out of the box, so anything is ad-hoc anyway (I always think of JSON Schema as “XML got it right, dang if we’d ever admit it”), but that is not the case for XML.


See also these GitHub repos with handwritten IDLs for Nova syntax grammars:


Hey I’m just seeing this, it sounds like I already did exactly what you said not to do :upside_down_face:. I made nova-xml which adds xml linting with XSD and DTD definitions using lemmix and tried my hand at writing a schema for syntax definitions too — nova-xml/ at main · robb-j/nova-xml · GitHub

It uses a custom catalog to provide extra schemas without them having to be hosted — catalog.xml

As always, if anyone has ideas of ways that Nova itself could help in this regard, feel free to send them my way! I can’t guarantee we’ll be able to prioritize them with the current schedule being what it is, but it’s good to know what developers want most. :pray:

It would be helpful if Nova could help me with Syntax validations. As-is, the Extension Console just logs vague errors when parsing syntax files:

Error loading syntax “Zig.xml”

The operation couldn’t be completed. (SKXMLDocumentErrorDomain error 111.)