Add domain-specific cross-reference syntax. As of this commit, that means new :qapi:mod:`block-core` and :qapi:any:`block-core` referencing syntax.
:mod: will only find modules, but :any: will find anything registered to the QAPI domain. (In forthcoming commits, this means commands, events, enums, etc.) Creating the cross-references is powered by the QAPIXRefRole class; resolving them is handled by QAPIDomain.resolve_xref(). QAPIXrefRole is copied almost verbatim from Sphinx's own PyXrefRole. PyXrefRole (and QAPIXrefRole) adds two features over the base class: (1) Creating a cross-reference with e.g. :py:class:`~class.name` instructs sphinx to omit the fully qualified parts of the resolved name from the actual link text. This may be useful in the future if we add namespaces to QAPI documentation, e.g. :qapi:cmd:`~qsd.blockdev-backup` could link to the QSD-specific documentation for blockdev-backup while omitting that prefix from the link text. (2) Prefixing the link target with a "." changes the search behavior to prefer locally-scoped items first. I think both of these are worth keeping to help manage future namespace issues between QEMU, QSD and QGA; but it's possible it's extraneous. It may possibly be worth keeping just to keep feature parity with Sphinx's other domains; e.g. "principle of least surprise". Dunno. Signed-off-by: John Snow <js...@redhat.com> --- docs/sphinx/qapi_domain.py | 88 +++++++++++++++++++++++++++++++++++++- 1 file changed, 87 insertions(+), 1 deletion(-) diff --git a/docs/sphinx/qapi_domain.py b/docs/sphinx/qapi_domain.py index 744956045e8..104bae709f3 100644 --- a/docs/sphinx/qapi_domain.py +++ b/docs/sphinx/qapi_domain.py @@ -31,6 +31,7 @@ ObjType, ) from sphinx.locale import _, __ +from sphinx.roles import XRefRole from sphinx.util import logging from sphinx.util.docutils import SphinxDirective from sphinx.util.nodes import make_id, make_refnode @@ -54,6 +55,54 @@ class ObjectEntry(NamedTuple): aliased: bool +class QAPIXRefRole(XRefRole): + + def process_link( + self, + env: BuildEnvironment, + refnode: Element, + has_explicit_title: bool, + title: str, + target: str, + ) -> tuple[str, str]: + refnode["qapi:module"] = env.ref_context.get("qapi:module") + + # Cross-references that begin with a tilde adjust the title to + # only show the reference without a leading module, even if one + # was provided. This is a Sphinx-standard syntax; give it + # priority over QAPI-specific type markup below. + hide_module = False + if target.startswith("~"): + hide_module = True + target = target[1:] + + # Type names that end with "?" are considered optional + # arguments and should be documented as such, but it's not + # part of the xref itself. + if target.endswith("?"): + refnode["qapi:optional"] = True + target = target[:-1] + + # Type names wrapped in brackets denote lists. strip the + # brackets and remember to add them back later. + if target.startswith("[") and target.endswith("]"): + refnode["qapi:array"] = True + target = target[1:-1] + + if has_explicit_title: + # Don't mess with the title at all if it was explicitly set. + # Explicit title syntax for references is e.g. + # :qapi:type:`target <explicit title>` + # and this explicit title overrides everything else here. + return title, target + + title = target + if hide_module: + title = target.split(".")[-1] + + return title, target + + class QAPIModule(SphinxDirective): """ Directive to mark description of a new module. @@ -219,7 +268,13 @@ class QAPIDomain(Domain): "module": QAPIModule, } - roles = {} + # These are all cross-reference roles; e.g. + # :qapi:cmd:`query-block`. The keys correlate to the names used in + # the object_types table values above. + roles = { + "mod": QAPIXRefRole(), + "any": QAPIXRefRole(), # reference *any* type of QAPI object. + } # Moved into the data property at runtime; # this is the internal index of reference-able objects. @@ -358,6 +413,37 @@ def find_obj( matches = [m for m in matches if not m[1].aliased] return matches + def resolve_xref( + self, + env: BuildEnvironment, + fromdocname: str, + builder: Builder, + typ: str, + target: str, + node: pending_xref, + contnode: Element, + ) -> nodes.reference | None: + modname = node.get("qapi:module") + matches = self.find_obj(modname, target, typ) + + if not matches: + return None + + if len(matches) > 1: + logger.warning( + __("more than one target found for cross-reference %r: %s"), + target, + ", ".join(match[0] for match in matches), + type="ref", + subtype="qapi", + location=node, + ) + + name, obj = matches[0] + return make_refnode( + builder, fromdocname, obj.docname, obj.node_id, contnode, name + ) + def resolve_any_xref( self, env: BuildEnvironment, -- 2.48.1