Improving doctag support and theme design in general #3170
Description
The problem
GitHub's doctag highlighting is so nice and making me jealous. I suppose we're quite close actually, but in thinking about this it brought up a lot of questions about how we classify doctors.
GitHub
Us
So lets tear apart a single doctag:
* @param {string | HighlightOptions} optionsOrCode - the code to highlight
And if we look closely we find:
*
comment decoration- The whole line starting with
@param
is technically documentation. (block scope) @param
the "tag" itself
-{}
punctuation around the typestring | HighlightOptions
the type itselfoptionsOrCode
variable name-
punctuationthe code to highlight
description
Currently we break that down line this:
- parent doctag
- type inside that
- variable inside that
- no way to target the description
This is "ok" until say you want to apply a background to perhaps just the tag portion... it seems we could perhaps be more granular here...
Also there is an issue with theme "leaking".
I've been thinking a lot about new theme designers and what type of experience they should have. Do we make it easy or hard to design themes, etc... how "fiddly" are we, etc... Right now if you don't even know what a doctag is and you design a theme without support then you probably get your doctag type
s and variable
s colored entirely unexpectedly with whatever color you used in the outside source. Is this desired behavior?
Or if you do design with support... you add a doctag
rule... did you remember the fact that variable
and type
could be nested within? See #3167 for another example of this unintentional "leaking" of CSS.
I wonder if all of these shouldn't be sub scopes instead to prevent this leakage - or perhaps the leakage is sometimes desirable? To me (with a theme designer hat on) I would NOT expect the type inside a comment doctag to automatically be highlighted exactly the same as a type inside my code proper.
Some possible scopes:
block.doctag
(TextMate would call thismeta.doctag
or something)doctag.tag
doctag.type
doctag.variable
doctag.description
- The
{}
in type would either not be included or labeled as punctuation.
I make the first a block/meta scope (vs just doctag
because (like TM) I think in general we'd like to discourage people highlighting entire scopes, but they can still be useful for targeted rules.
For reference TextMate does this with it's top-level scopes (entity.name
, storage.type
, variable
), so perhaps we're not doing the wrong thing after-all. Though it still feels like the behavior where doctag
wraps everything should perhaps be changed.
comment.block.documentation
(the larger block scope)@param
-storage.type.class.jsdoc
string
-entity.name.type.instance.jsdoc
codeToHighlight
-variable.other.jsdoc
- the description is given no specific scope
There is actually no scope for the "whole doctag line"... comment.block.documentation
is applied to the entire /**
comment, irregardless of doctors...
Other ideas
Perhaps this is solved with better docs, or some sort of theme design tool with examples? IE, a minimal version of "demo" that has to look "passable" for multiple languages, etc...
CC @highlightjs/theme-maintainers @highlightjs/core