Commit Graph

71 Commits

Author SHA1 Message Date
John Snow
d5e2f3d03c qapi/parser.py: assert member.info is present in connect_member
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240315152301.3621858-21-armbru@redhat.com>
2024-04-24 10:03:54 +02:00
John Snow
7c6e446476 qapi/parser: demote QAPIExpression to Dict[str, Any]
Dict[str, object] is a stricter type, but with the way that code is
currently arranged, it is infeasible to enforce this strictness.

In particular, although expr.py's entire raison d'être is normalization
and type-checking of QAPI Expressions, that type information is not
"remembered" in any meaningful way by mypy because each individual
expression is not downcast to a specific expression type that holds all
the details of each expression's unique form.

As a result, all of the code in schema.py that deals with actually
creating type-safe specialized structures has no guarantee (myopically)
that the data it is being passed is correct.

There are two ways to solve this:

(1) Re-assert that the incoming data is in the shape we expect it to be, or
(2) Disable type checking for this data.

(1) is appealing to my sense of strictness, but I gotta concede that it
is asinine to re-check the shape of a QAPIExpression in schema.py when
expr.py has just completed that work at length. The duplication of code
and the nightmare thought of needing to update both locations if and
when we change the shape of these structures makes me extremely
reluctant to go down this route.

(2) allows us the chance to miss updating types in the case that types
are updated in expr.py, but it *is* an awful lot simpler and,
importantly, gets us closer to type checking schema.py *at
all*. Something is better than nothing, I'd argue.

So, do the simpler dumber thing and worry about future strictness
improvements later.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240315152301.3621858-20-armbru@redhat.com>
2024-04-24 10:03:54 +02:00
John Snow
2daf52df8b qapi/parser: shush up pylint
Shhh!

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240315152301.3621858-3-armbru@redhat.com>
2024-04-24 10:03:54 +02:00
John Snow
4f8f199fa5 qapi/parser: fix typo - self.returns.info => self.errors.info
Small copy-pasto. The correct info field to use in this conditional
block is self.errors.info.

Fixes: 3a025d3d1f
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240315152301.3621858-2-armbru@redhat.com>
2024-04-24 10:03:54 +02:00
Markus Armbruster
e1f684ea2e qapi: Reject "Returns" section when command doesn't return anything
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240227113921.236097-14-armbru@redhat.com>
2024-03-04 07:12:40 +01:00
Markus Armbruster
3a025d3d1f qapi: New documentation section tag "Errors"
We use section "Returns" for documenting both success and error
response of commands.

I intend to generate better command success response documentation.
Easier when "Returns" documents just he success response.

Create new section tag "Errors".  The next two commits will move error
response documentation from "Returns" sections to "Errors" sections.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240227113921.236097-4-armbru@redhat.com>
2024-03-04 07:12:40 +01:00
Markus Armbruster
51e97c14fb qapi: Slightly clearer error message for invalid "Returns" section
Change "'Returns:' is only valid for commands" to "'Returns' section
is only valid for commands".

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240227113921.236097-3-armbru@redhat.com>
2024-03-04 07:12:40 +01:00
Markus Armbruster
ba7f63f9a4 qapi: Memorize since & returns sections
This is chiefly to make code that looks up these sections easier to
read.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240227113921.236097-2-armbru@redhat.com>
2024-03-04 07:12:40 +01:00
Markus Armbruster
adb0193b90 qapi: Divorce QAPIDoc from QAPIParseError
QAPIDoc stores a reference to QAPIParser just to pass it to
QAPIParseError.  The resulting error position depends on the state of
the parser.  It happens to be the current comment line.  Servicable,
but action at a distance.

The commit before previous moved most uses of QAPIParseError from
QAPIDoc to QAPIParser.  There are just three left.  Convert them to
QAPISemError.  This involves passing info to a few methods.  Then drop
the reference to QAPIParser.

The three errors lose the column number.  Not really interesting here:
it's the comment line's indentation.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240216145841.2099240-17-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2024-02-26 10:43:56 +01:00
Markus Armbruster
629c5075aa qapi: Reject multiple and empty feature descriptions
The parser recognizes only the first "Features:" line.  Any subsequent
ones are treated as ordinary text, as visible in test case
doc-duplicate-features.  Recognize "Features:" lines anywhere.  A
second one is an error.

A 'Features:' line without any features is useless, but not an error.
Make it an error.  This makes detecting a second "Features:" line
easier.

qapi/run-state.json actually has an instance of this since commit
fe17522d85 (qapi: Remove deprecated 'singlestep' member of
StatusInfo).  Clean it up.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240216145841.2099240-16-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2024-02-26 10:43:56 +01:00
Markus Armbruster
3d035cd2cc qapi: Rewrite doc comment parser
QAPISchemaParser is a conventional recursive descent parser.  Except
QAPISchemaParser.get_doc() delegates most of the doc comment parsing
work to a state machine in QAPIDoc.  The state machine doesn't get
tokens like a recursive descent parser, it is fed tokens.

I find this state machine rather opaque and hard to maintain.

Replace it by a conventional parser, all in QAPISchemaParser.  Less
code, and (at least in my opinion) easier to understand.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240216145841.2099240-15-armbru@redhat.com>
Tested-by: Daniel P. Berrangé <berrange@redhat.com>
2024-02-26 10:43:56 +01:00
Markus Armbruster
0b82a7440c qapi: Merge adjacent untagged sections
The parser mostly doesn't create adjacent untagged sections, and
merging the ones it does create is hardly worth the bother.  I'm doing
it to avoid behavioral change in the next commit.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240216145841.2099240-14-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2024-02-26 10:43:56 +01:00
Markus Armbruster
66227e9047 qapi: Recognize section tags and 'Features:' only after blank line
Putting a blank line before section tags and 'Features:' is good,
existing practice.  Enforce it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240216145841.2099240-12-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2024-02-26 10:43:56 +01:00
Markus Armbruster
d23055b8db qapi: Require descriptions and tagged sections to be indented
By convention, we indent the second and subsequent lines of
descriptions and tagged sections, except for examples.

Turn this into a hard rule, and apply it to examples, too.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240216145841.2099240-11-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
[Straightforward conflicts in qapi/migration.json resolved]
2024-02-26 10:43:56 +01:00
Markus Armbruster
56c64dd60a qapi: Reject section heading in the middle of a doc comment
docs/devel/qapi-code-gen.txt claims "A heading line must be the first
line of the documentation comment block" since commit
55ec69f8b1 (docs/devel/qapi-code-gen.txt: Update to new rST backend
conventions).  Not true, we have code to make it work anywhere in a
free-form doc comment: commit dcdc07a97c (qapi: Make section headings
start a new doc comment block).

Make it true, for simplicity's sake.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240216145841.2099240-10-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2024-02-26 10:43:56 +01:00
Markus Armbruster
31c54b92ad qapi: Rename QAPIDoc.Section.name to .tag
Since the previous commit, QAPIDoc.Section.name is either
None (untagged section) or the section's tag string ('Returns',
'@name', ...).  Rename it to .tag.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240216145841.2099240-9-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2024-02-26 10:43:56 +01:00
Markus Armbruster
573e2223f9 qapi: Improve error message for empty doc sections
Improve the message for an empty tagged section from

    empty doc section 'Note'

to

    text required after 'Note:'

and the message for an empty argument or feature description from

    empty doc section 'foo'

to

    text required after '@foo:'

Improve the error position to refer to the beginning of the empty
section instead of its end.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240216145841.2099240-8-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2024-02-26 10:43:56 +01:00
Markus Armbruster
bf00dc19f3 qapi: Improve error position for bogus invalid "Returns" section
When something other than a command has a "Returns" section, the error
message points to the beginning of the definition comment.  Point to
the "Returns" section instead.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240216145841.2099240-7-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2024-02-26 10:43:56 +01:00
Markus Armbruster
15333abed9 qapi: Improve error position for bogus argument descriptions
When documented arguments don't exist, the error message points to the
beginning of the definition comment.  Point to the first bogus
argument description instead.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240216145841.2099240-6-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2024-02-26 10:43:56 +01:00
Markus Armbruster
0cec50119f qapi: Require member documentation (with loophole)
The QAPI generator forces you to document your stuff.  Except for
command arguments, event data, and members of enum and object types:
these the generator silently "documents" as "Not documented".

We can't require proper documentation there without first fixing all
the offenders.  We've always had too many offenders to pull that off.
Right now, we have more than 500.  Worse, we seem to fix old ones no
faster than we add new ones: in the past year, we fixed 22 ones, but
added 26 new ones.

To help arrest the backsliding, make missing documentation an error
unless the command, type, or event is in listed in new pragma
documentation-exceptions.

List all the current offenders: 117 commands and types in qapi/, and 9
in qga/.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240205074709.3613229-7-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2024-02-12 10:04:31 +01:00
Markus Armbruster
b0b1313eb2 qapi: Fix dangling references to docs/devel/qapi-code-gen.txt
Conversion of docs/devel/qapi-code-gen.txt to ReST left several
dangling references behind.  Fix them to point to
docs/devel/qapi-code-gen.rst.

Fixes: f7aa076dbd (docs: convert qapi-code-gen.txt to ReST)
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240120095327.666239-4-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2024-01-26 07:04:53 +01:00
John Snow
a6c5d159ce qapi: re-establish linting baseline
Some very minor housekeeping to make the linters happy once more.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-ID: <20231004230532.3002201-4-jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2023-10-19 07:02:29 +02:00
Markus Armbruster
290e48e8f1 qapi: Improve error message for description following section
The error message is bad when the section is untagged.  For instance,
test case doc-interleaved-section produces "'@foobar:' can't follow
'Note' section", which is okay, but if we drop the "Note:" tag, we get
"'@foobar:' can't follow 'None' section, which is bad.

Change the error message to "description of '@foobar:' follows a
section".

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230510141637.3685080-1-armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
[Conflict with commit 3e32dca3f0 resolved]
2023-05-22 10:03:26 +02:00
Markus Armbruster
d27e7c3593 qapi/parser: Drop two bad type hints for now
Two type hints fail centos-stream-8-x86_64 CI.  They are actually
broken.  Changing them to Optional[re.Match[str]] fixes them locally
for me, but then CI fails differently.  Drop them for now.

Fixes: 3e32dca3f0 (qapi: Rewrite parsing of doc comment section symbols and tags)
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230517061600.1782455-1-armbru@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-05-17 10:18:33 -07:00
Markus Armbruster
eb59cf7628 qapi: Section parameter @indent is no longer used, drop
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230428105429.1687850-15-armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
2023-05-10 10:01:01 +02:00
Markus Armbruster
08349786c8 qapi: Relax doc string @name: description indentation rules
The QAPI schema doc comment language provides special syntax for
command and event arguments, struct and union members, alternate
branches, enumeration values, and features: descriptions starting with
"@name:".

By convention, we format them like this:

    # @name: Lorem ipsum dolor sit amet, consectetur adipiscing elit,
    #        sed do eiusmod tempor incididunt ut labore et dolore
    #        magna aliqua.

Okay for names as short as "name", but we have much longer ones.  Their
description gets squeezed against the right margin, like this:

    # @dirty-sync-missed-zero-copy: Number of times dirty RAM synchronization could
    #                               not avoid copying dirty pages. This is between
    #                               0 and @dirty-sync-count * @multifd-channels.
    #                               (since 7.1)

The description text is effectively just 50 characters wide.  Easy
enough to read, but can be cumbersome to write.

The awkward squeeze against the right margin makes people go beyond it,
which produces two undesirables: arguments about style, and descriptions
that are unnecessarily hard to read, like this one:

    # @postcopy-vcpu-blocktime: list of the postcopy blocktime per vCPU.  This is
    #                           only present when the postcopy-blocktime migration capability
    #                           is enabled. (Since 3.0)

We could instead format it like

    # @postcopy-vcpu-blocktime:
    # list of the postcopy blocktime per vCPU.  This is only present
    # when the postcopy-blocktime migration capability is
    # enabled. (Since 3.0)

or, since the commit before previous, like

    # @postcopy-vcpu-blocktime:
    # 	  list of the postcopy blocktime per vCPU.  This is only present
    # 	  when the postcopy-blocktime migration capability is
    # 	  enabled. (Since 3.0)

However, I'd rather have

    # @postcopy-vcpu-blocktime: list of the postcopy blocktime per vCPU.
    #     This is only present when the postcopy-blocktime migration
    #     capability is enabled.  (Since 3.0)

because this is how rST field and option lists work.

To get this, we need to let the first non-blank line after the
"@name:" line determine expected indentation.

This fills up the indentation pitfall mentioned in
docs/devel/qapi-code-gen.rst.  A related pitfall still exists.  Update
the text to show it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230428105429.1687850-14-armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
[Work around lack of walrus operator in Python 3.7 and older]
2023-05-10 10:00:40 +02:00
Markus Armbruster
3e32dca3f0 qapi: Rewrite parsing of doc comment section symbols and tags
To recognize a line starting with a section symbol and or tag, we
first split it at the first space, then examine the part left of the
space.  We can just as well examine the unsplit line, so do that.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230428105429.1687850-13-armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
[Work around lack of walrus operator in Python 3.7 and older]
2023-05-10 09:34:17 +02:00
Markus Armbruster
9b2c6746d3 qapi: Fix argument description indentation stripping
When an argument's description starts on the line after the "#arg: "
line, indentation is stripped only from the description's first line,
as demonstrated by the previous commit.  Moreover, subsequent lines
with less indentation are not rejected.

Make the first line's indentation the expected indentation for the
remainder of the description.  This fixes indentation stripping, and
also requires at least that much indentation.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230428105429.1687850-12-armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
2023-05-09 09:12:48 +02:00
Markus Armbruster
5b5fe0e018 qapi: Fix crash on stray double quote character
When the lexer chokes on a stray character, its shows the characters
until the next structural character in the error message.  It uses a
regular expression to match a non-empty string of non-structural
characters.  Bug: the regular expression treats '"' as structural.
When the lexer chokes on '"', the match fails, and trips
must_match()'s assertion.  Fix the regular expression.

Fixes: 14c3279502 (qapi: Improve reporting of lexical errors)
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230428105429.1687850-4-armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
2023-05-09 08:51:58 +02:00
John Snow
c7b7a7ded9 qapi: remove JSON value FIXME
With the two major JSON-ish type hierarchies clarified for distinct
purposes; QAPIExpression for parsed expressions and JSONValue for
introspection data, remove this FIXME as no longer an action item.

A third JSON-y data type, _ExprValue, is not meant to represent JSON in
the abstract but rather only the possible legal return values from a
single function, get_expr(). It isn't appropriate to attempt to merge it
with either of the above two types.

In theory, it may be possible to define a completely agnostic
one-size-fits-all JSON type hierarchy that any other user could borrow -
in practice, it's tough to wrangle the differences between invariant,
covariant and contravariant types: input and output parameters demand
different properties of such a structure.

However, QAPIExpression serves to authoritatively type user input to the
QAPI parser, while JSONValue serves to authoritatively type qapi
generator *output* to be served back to client users at runtime via
QMP. The AST for these two types are different and cannot be wholly
merged into a unified syntax.

They could, in theory, share some JSON primitive definitions. In
practice, this is currently more trouble than it's worth with mypy's
current expressive power. As such, declare this "done enough for now".

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20230215000011.1725012-7-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
2023-02-23 13:01:45 +01:00
John Snow
67a81f9fb7 qapi: remove _JSONObject
We can remove this alias as it only has two usages now, and no longer
pays for the confusion of "yet another type".

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20230215000011.1725012-6-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
2023-02-23 13:01:45 +01:00
John Snow
420110591c qapi/parser: add QAPIExpression type
This patch creates a new type, QAPIExpression, which represents a parsed
expression complete with QAPIDoc and QAPISourceInfo.

This patch turns parser.exprs into a list of QAPIExpression instead,
and adjusts expr.py to match.

This allows the types we specify in parser.py to be "remembered" all the
way through expr.py and into schema.py. Several assertions around
packing and unpacking this data can be removed as a result.

It also corrects a harmless typing error.  Before the patch,
check_exprs() allegedly takes a List[_JSONObject].  It actually takes
a list of dicts of the form

    {'expr': E, 'info': I, 'doc': D}

where E is of type _ExprValue, I is of type QAPISourceInfo, and D is
of type QAPIDoc.  Key 'doc' is optional.  This is not a _JSONObject!
Passes type checking anyway, because _JSONObject is Dict[str, object].

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20230215000011.1725012-5-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Commit message amended to point out the typing fix]
2023-02-23 13:01:45 +01:00
John Snow
18e3673e0f qapi/parser: Silence too-few-public-methods warning
Eh. Not worth the fuss today. There are bigger fish to fry.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210930205716.1148693-13-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-10-02 07:33:42 +02:00
John Snow
15acf48cfe qapi/parser: Add FIXME for consolidating JSON-related types
The fix for this comment is forthcoming in a future commit, but this
will keep me honest. The linting configuration in ./python/setup.cfg
prohibits 'FIXME' comments. A goal of this long-running series is to
move ./scripts/qapi to ./python/qemu/qapi so that the QAPI generator is
regularly type-checked by GitLab CI.

This comment is a time-bomb to force me to address this issue prior to
that step.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210930205716.1148693-11-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-10-02 07:33:42 +02:00
John Snow
5f0d9f3bc7 qapi/parser: add type hint annotations (QAPIDoc)
Annotations do not change runtime behavior.
This commit consists of only annotations.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210930205716.1148693-10-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-10-02 07:33:42 +02:00
John Snow
e7ac60fcd0 qapi/parser: add import cycle workaround
Adding static types causes a cycle in the QAPI generator:
[schema -> expr -> parser -> schema]. It exists because the QAPIDoc
class needs the names of types defined by the schema module, but the
schema module needs to import both expr.py/parser.py to do its actual
parsing.

Ultimately, the layering violation is that parser.py should not have any
knowledge of specifics of the Schema. QAPIDoc performs double-duty here
both as a parser *and* as a finalized object that is part of the schema.

In this patch, add the offending type hints alongside the workaround to
avoid the cycle becoming a problem at runtime. See
https://mypy.readthedocs.io/en/latest/runtime_troubles.html#import-cycles
for more information on this workaround technique.

I see three ultimate resolutions here:

(1) Just keep this patch and use the TYPE_CHECKING trick to eliminate
    the cycle which is only present during static analysis.

(2) Don't bother to annotate connect_member() et al, give them 'object'
    or 'Any'. I don't particularly like this, because it diminishes the
    usefulness of type hints for documentation purposes. Still, it's an
    extremely quick fix.

(3) Reimplement doc <--> definition correlation directly in schema.py,
    integrating doc fields directly into QAPISchemaMember and relieving
    the QAPIDoc class of the responsibility. Users of the information
    would instead visit the members first and retrieve their
    documentation instead of the inverse operation -- visiting the
    documentation and retrieving their members.

My preference is (3), but in the short-term (1) is the easiest way to
have my cake (strong type hints) and eat it too (Not have import
cycles). Do (1) for now, but plan for (3).

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210930205716.1148693-9-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-10-02 07:33:42 +02:00
John Snow
f4c05aaf14 qapi/parser: Introduce NullSection
Here's the weird bit. QAPIDoc generally expects -- virtually everywhere
-- that it will always have a current section. The sole exception to
this is in the case that end_comment() is called, which leaves us with
*no* section. However, in this case, we also don't expect to actually
ever mutate the comment contents ever again.

NullSection is just a Null-object that allows us to maintain the
invariant that we *always* have a current section, enforced by static
typing -- allowing us to type that field as QAPIDoc.Section instead of
the more ambiguous Optional[QAPIDoc.Section].

end_section is renamed to switch_section and now accepts as an argument
the new section to activate, clarifying that no callers ever just
unilaterally end a section; they only do so when starting a new section.

Signed-off-by: John Snow <jsnow@redhat.com>

Message-Id: <20210930205716.1148693-8-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-10-02 07:33:42 +02:00
John Snow
1e20a77576 qapi/parser: clarify _end_section() logic
The "if self._section" clause in end_section is mysterious: In which
circumstances might we end a section when we don't have one?

QAPIDoc always expects there to be a "current section", only except
after a call to end_comment(). This actually *shouldn't* ever be 'None',
so let's remove that logic so I don't wonder why it's like this again in
three months.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210930205716.1148693-7-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-10-02 07:33:42 +02:00
John Snow
cd87c14cde qapi/parser: remove FIXME comment from _append_body_line
True, we do not check the validity of this symbol -- but we don't check
the validity of definition names during parse, either -- that happens
later, during the expr check. I don't want to introduce a dependency on
expr.py:check_name_str here and introduce a cycle.

Instead, rest assured that a documentation block is required for each
definition. This requirement uses the names of each section to ensure
that we fulfilled this requirement.

e.g., let's say that block-core.json has a comment block for
"Snapshot!Info" by accident. We'll see this error message:

In file included from ../../qapi/block.json:8:
../../qapi/block-core.json: In struct 'SnapshotInfo':
../../qapi/block-core.json:38: documentation comment is for 'Snapshot!Info'

That's a pretty decent error message.

Now, let's say that we actually mangle it twice, identically:

../../qapi/block-core.json: In struct 'Snapshot!Info':
../../qapi/block-core.json:38: struct has an invalid name

That's also pretty decent. If we forget to fix it in both places, we'll
just be back to the first error.

Therefore, let's just drop this FIXME and adjust the error message to
not imply a more thorough check than is actually performed.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210930205716.1148693-6-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-10-02 07:33:42 +02:00
John Snow
012336a152 qapi/parser: fix unused check_args_section arguments
Pylint informs us we're not using these arguments. Oops, it's
right. Correct the error message and remove the remaining unused
parameter.

Fix test output now that the error message is improved.

Fixes: e151941d1b
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210930205716.1148693-4-jsnow@redhat.com>
[Commit message formatting tweaked]
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-10-02 07:33:41 +02:00
John Snow
d4092ffa26 qapi/parser: add docstrings
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210519183951.3946870-16-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Doc string spacing tweaked slightly]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-05-20 17:10:09 +02:00
John Snow
013a3aceb5 qapi/parser: Remove superfluous list comprehension
A generator suffices (and quiets a pylint warning).

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210519183951.3946870-14-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-05-20 11:28:29 +02:00
John Snow
810aff8f29 qapi/parser: add type hint annotations
Annotations do not change runtime behavior.
This commit *only* adds annotations.

(Annotations for QAPIDoc are in a forthcoming commit.)

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210519183951.3946870-13-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-05-20 11:28:28 +02:00
John Snow
03386200b9 qapi/parser: Rework _check_pragma_list_of_str as a TypeGuard
TypeGuards wont exist in Python proper until 3.10. Ah well. We can hack
up our own by declaring this function to return the type we claim it
checks for and using this to safely downcast object -> List[str].

In so doing, I bring this function under _pragma so it can use the
'info' object in its closure. Having done this, _pragma also now no
longer needs to take a 'self' parameter, so drop it.

To help with line-length, and with the context evident from its new
scope, rename the function to the shorter check_list_str().

Signed-off-by: John Snow <jsnow@redhat.com>

Message-Id: <20210519183951.3946870-12-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-05-20 11:28:28 +02:00
John Snow
c256263f3d qapi/parser: Fix token membership tests when token can be None
When the token can be None (EOF), we can't use 'x in "abc"' style
membership tests to group types of tokens together, because 'None in
"abc"' is a TypeError.

Easy enough to fix. (Use a tuple: It's neither a static typing error nor
a runtime error to check for None in Tuple[str, ...])

Add tests to prevent a regression. (Note: they cannot be added prior to
this fix, as the unhandled stack trace will not match test output in the
CI system.)

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210519183951.3946870-11-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-05-20 11:28:28 +02:00
John Snow
e0e8a0ac2e qapi: add must_match helper
Mypy cannot generally understand that these regex functions cannot
possibly fail. Add a "must_match" helper that makes this clear for
mypy.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210519183951.3946870-10-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-05-20 11:28:28 +02:00
John Snow
43b1be65f0 qapi/parser: Use @staticmethod where appropriate
No self, no thank you!

(Quiets pylint warnings.)

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210519183951.3946870-9-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-05-20 11:28:28 +02:00
John Snow
234dce2c2d qapi/parser: assert object keys are strings
The single quote token implies the value is a string. Assert this to be
the case, to allow us to write an accurate return type for get_members.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210519183951.3946870-8-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-05-20 11:28:28 +02:00
John Snow
9cd0205d55 qapi/parser: enforce all top-level expressions must be dict in _parse()
Instead of using get_expr nested=False, allow get_expr to always return
any expression. In exchange, add a new error message to the top-level
parser that explains the semantic error: Top-level expressions must
always be JSON objects.

This helps mypy understand the rest of this function which assumes that
get_expr did indeed return a dict.

The exception type changes from QAPIParseError to QAPISemError as a
result, and the error message in two tests now changes.

Signed-off-by: John Snow <jsnow@redhat.com>

Message-Id: <20210519183951.3946870-7-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-05-20 11:28:28 +02:00
John Snow
7c610ce6a9 qapi/parser: Assert lexer value is a string
The type checker can't narrow the type of the token value to string,
because it's only loosely correlated with the return token.

We know that a token of '#' should always have a "str" value.
Add an assertion.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210519183951.3946870-6-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-05-20 11:28:27 +02:00