Simple unions predate flat unions. Having both complicates the QAPI
schema language and the QAPI generator. We haven't been using simple
unions in new code for a long time, because they are less flexible and
somewhat awkward on the wire.
The previous commits eliminated simple union from the tree. Now drop
them from the QAPI schema language entirely, and update mentions of
"flat union" to just "union".
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210917143134.412106-22-armbru@redhat.com>
This reverts commit 3313b61's changes to tests/qapi-schema/, except
for tests/qapi-schema/doc-*.
We could keep some of these doc comments to serve as positive test
cases. However, they don't actually add to what we get from doc
comment use in actual schemas, as we we don't test output matches
expectations, and don't systematically cover doc comment features.
Proper positive test coverage would be nice.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-4-git-send-email-armbru@redhat.com>
As the name suggests, the qapi2texi script converts JSON QAPI
description into a texi file suitable for different target
formats (info/man/txt/pdf/html...).
It parses the following kind of blocks:
Free-form:
##
# = Section
# == Subsection
#
# Some text foo with *emphasis*
# 1. with a list
# 2. like that
#
# And some code:
# | $ echo foo
# | -> do this
# | <- get that
#
##
Symbol description:
##
# @symbol:
#
# Symbol body ditto ergo sum. Foo bar
# baz ding.
#
# @param1: the frob to frobnicate
# @param2: #optional how hard to frobnicate
#
# Returns: the frobnicated frob.
# If frob isn't frobnicatable, GenericError.
#
# Since: version
# Notes: notes, comments can have
# - itemized list
# - like this
#
# Example:
#
# -> { "execute": "quit" }
# <- { "return": {} }
#
##
That's roughly following the following EBNF grammar:
api_comment = "##\n" comment "##\n"
comment = freeform_comment | symbol_comment
freeform_comment = { "# " text "\n" | "#\n" }
symbol_comment = "# @" name ":\n" { member | tag_section | freeform_comment }
member = "# @" name ':' [ text ] "\n" freeform_comment
tag_section = "# " ( "Returns:", "Since:", "Note:", "Notes:", "Example:", "Examples:" ) [ text ] "\n" freeform_comment
text = free text with markup
Note that the grammar is ambiguous: a line "# @foo:\n" can be parsed
both as freeform_comment and as symbol_comment. The actual parser
recognizes symbol_comment.
See docs/qapi-code-gen.txt for more details.
Deficiencies and limitations:
- the generated QMP documentation includes internal types
- union type support is lacking
- type information is lacking in generated documentation
- doc comment error message positions are imprecise, they point
to the beginning of the comment.
- a few minor issues, all marked TODO/FIXME in the code
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20170113144135.5150-16-marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[test-qapi.py tweaked to avoid trailing empty lines in .out]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Referring to "type" as both a meta-type (built-in, enum, union,
alternate, or struct) and a specific type (the name that the
schema uses for declaring structs) is confusing. Do the bulk of
the conversion to "struct" in qapi schema, with a fairly
mechanical:
for f in `find -name '*.json'; do sed -i "s/'type'/'struct'/"; done
followed by manually filtering out the places where we have a
'type' embedded in 'data'. Then tweak a couple of tests whose
output changes slightly due to longer lines.
I also verified that the generated files for QMP and QGA (such
as qmp-commands.h) are the same before and after, as assurance
that I didn't leave in any accidental member name changes.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
None of the existing QMP or QGA interfaces uses a union with a
base type but no discriminator; it is easier to avoid this in the
generator to save room for other future extensions more likely to
be useful. An earlier commit added a union-base-no-discriminator
test to ensure that we eventually give a decent error message;
likewise, removing UserDefUnion outright is okay, because we moved
all the tests we wish to keep into the tests of the simple union
UserDefNativeListUnion in the previous commit. Now is the time to
actually forbid simple union with base, and remove the last
vestiges from the testsuite.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Demonstrate that the qapi generator doesn't deal well with unions
that aren't up to par. Later patches will update the expected
reseults as the generator is made stricter. A few tests work
as planned, but most show poor or missing error messages.
Of particular note, qapi-code-gen.txt documents 'base' only for
flat unions, but the tests here demonstrate that we currently allow
a 'base' to a simple union, although it is exercised only in the
testsuite. Later patches will remove this undocumented feature, to
give us more flexibility in adding other future extensions to union
types. For example, one possible extension is the idea of a
type-safe simple enum, where added fields tie the discriminator to
a user-defined enum type rather than creating an implicit enum from
the names in 'data'. But adding such safety on top of a simple
enum with a base type could look ambiguous with a flat enum;
besides, the documentation also mentions how any simple union can
be represented by an equivalent flat union. So it will be simpler
to just outlaw support for something we aren't using.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
