Commit Graph

31 Commits

Author SHA1 Message Date
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
John Snow
16ff40acc9 qapi/parser: factor parsing routine into method
For the sake of keeping __init__ smaller (and treating it more like a
gallery of what state variables we can expect to see), put the actual
parsing action into a parse method. It remains invoked from the init
method to reduce churn.

To accomplish this, @previously_included becomes the private data
member ._included, and the filename is stashed as ._fname.

Add any missing declarations to the init method, and group them by
function so they can be understood quickly at a glance.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210519183951.3946870-5-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
John Snow
b2b31fdf9b qapi/source: Remove line number from QAPISourceInfo initializer
With the QAPISourceInfo(None, None, None) construct gone, there's no
longer any reason to have to specify that a file starts on the first
line. Remove it from the initializer and default it to 1.

Remove the last vestiges where we check for 'line' being unset, that
can't happen, now.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210519183951.3946870-4-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
John Snow
3404e57410 qapi/parser: Don't try to handle file errors
Fixes: f5d4361cda
Fixes: 52a474180a
Fixes: 46f49468c6

Remove the try/except block that handles file-opening errors in
QAPISchemaParser.__init__() and add one each to
QAPISchemaParser._include() and QAPISchema.__init__() respectively.

This simultaneously fixes the typing of info.fname (f5d4361cda), A
static typing violation in test-qapi (46f49468c6), and a regression of
an error message (52a474180a).

The short-ish version of what motivates this patch is:

- It's hard to write a good error message in the init method,
  because we need to determine the context of our caller to do so.
  It's easier to just let the caller write the message.
- We don't want to allow QAPISourceInfo(None, None, None) to exist. The
  typing introduced by commit f5d4361cda types the 'fname' field as
  (non-optional) str, which was premature until the removal of this
  construct.
- Errors made using such an object are currently incorrect (since
  52a474180a)
- It's not technically a semantic error if we cannot open the schema.
- There are various typing constraints that make mixing these two cases
  undesirable for a single special case.
- test-qapi's code handling an fname of 'None' is now dead, drop it.
  Additionally, Not all QAPIError objects have an 'info' field (since
  46f49468), so deleting this stanza corrects a typing oversight in
  test-qapi introduced by that commit.

Other considerations:

- open() is moved to a 'with' block to ensure file pointers are
  cleaned up deterministically.
- Python 3.3 deprecated IOError and made it a synonym for OSError.
  Avoid the misleading perception these exception handlers are
  narrower than they really are.

The long version:

The error message here is incorrect (since commit 52a474180a):

> python3 qapi-gen.py 'fake.json'
qapi-gen.py: qapi-gen.py: can't read schema file 'fake.json': No such file or directory

In pursuing it, we find that QAPISourceInfo has a special accommodation
for when there's no filename. Meanwhile, the intent when QAPISourceInfo
was typed (f5d4361cda) was non-optional 'str'. This usage was
overlooked.

To remove this, I'd want to avoid having a "fake" QAPISourceInfo
object. I also don't want to explicitly begin accommodating
QAPISourceInfo itself being None, because we actually want to eventually
prove that this can never happen -- We don't want to confuse "The file
isn't open yet" with "This error stems from a definition that wasn't
defined in any file".

(An earlier series tried to create a dummy info object, but it was tough
to prove in review that it worked correctly without creating new
regressions. This patch avoids that distraction. We would like to first
prove that we never raise QAPISemError for any built-in object before we
add "special" info objects. We aren't ready to do that yet.)

So, which way out of the labyrinth?

Here's one way: Don't try to handle errors at a level with "mixed"
semantic contexts; i.e. don't mix inclusion errors (should report a
source line where the include was triggered) and command line errors
(where we specified a file we couldn't read).

Remove the error handling from the initializer of the parser. Pythonic!
Now it's the caller's job to figure out what to do about it. Handle the
error in QAPISchemaParser._include() instead, where we can write a
targeted error message where we are guaranteed to have an 'info' context
to report with.

The root level error can similarly move to QAPISchema.__init__(), where
we know we'll never have an info context to report with, so we use a
more abstract error type.

Now the error looks sensible again:

> python3 qapi-gen.py 'fake.json'
qapi-gen.py: can't read schema file 'fake.json': No such file or directory

With these error cases separated, QAPISourceInfo can be solidified as
never having placeholder arguments that violate our desired types. Clean
up test-qapi along similar lines.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210519183951.3946870-2-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
John Snow
ac6a7d8884 qapi/error.py: move QAPIParseError to parser.py
Keeping it in error.py will create some cyclic import problems when we
add types to the QAPISchemaParser. Callers don't need to know the
details of QAPIParseError unless they are parsing or dealing directly
with the parser, so this won't create any harsh new requirements for
callers in the general case.

Update error.py with a little docstring that gives a nod to where the
error may now be found.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210421192233.3542904-6-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-04-30 12:59:54 +02:00
Markus Armbruster
05ebf841ef qapi: Enforce command naming rules
Command names should be lower-case.  Enforce this.  Fix the fixable
offenders (all in tests/), and add the remainder to pragma
command-name-exceptions.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210323094025.3569441-25-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2021-03-23 22:31:05 +01:00
Markus Armbruster
b86df37478 qapi: Rename pragma *-whitelist to *-exceptions
Rename pragma returns-whitelist to command-returns-exceptions, and
name-case-whitelist to member-name-case-exceptions.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210323094025.3569441-20-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2021-03-23 22:31:05 +01:00
Markus Armbruster
4a67bd31a4 qapi: Factor out QAPISchemaParser._check_pragma_list_of_str()
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210323094025.3569441-17-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2021-03-23 22:31:05 +01:00
Markus Armbruster
0e92a19b8c qapi: Fix parse errors for removal of null from schema language
Commit 9d55380b5a "qapi: Remove null from schema language" (v4.2.0)
neglected to update two error messages.  Do that now.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210224101442.1837475-1-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2021-03-05 15:40:50 +01:00
John Snow
67fea57502 qapi: enforce import order/styling with isort
While we're mucking around with imports, we might as well formalize the
style we use. Let's use isort to do it for us.

lines_after_imports=2: Use two lines after imports, to match PEP8's
desire to have "two lines before and after" class definitions, which are
likely to start immediately after imports.

force_sort_within_sections: Intermingles "from x" and "import x" style
statements, such that sorting is always performed strictly on the module
name itself.

force_grid_wrap=4: Four or more imports from a single module will force
the one-per-line style that's more git-friendly. This will generally
happen for 'typing' imports.

multi_line_output=3: Uses the one-per-line indented style for long
imports.

include_trailing_comma: Adds a comma to the last import in a group,
which makes git conflicts nicer to deal with, generally.

line_length: 72 is chosen to match PEP8's "docstrings and comments" line
length limit. If you have a single line import that exceeds 72
characters, your names are too long!

Suggested-by: Cleber Rosa <crosa@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Tested-by: Cleber Rosa <crosa@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201009161558.107041-8-jsnow@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2020-10-10 11:37:47 +02:00
John Snow
7137a96099 qapi: Prefer explicit relative imports
All of the QAPI include statements are changed to be package-aware, as
explicit relative imports.

A quirk of Python packages is that the name of the package exists only
*outside* of the package. This means that to a module inside of the qapi
folder, there is inherently no such thing as the "qapi" package. The
reason these imports work is because the "qapi" package exists in the
context of the caller -- the execution shim, where sys.path includes a
directory that has a 'qapi' folder in it.

When we write "from qapi import sibling", we are NOT referencing the folder
'qapi', but rather "any package named qapi in sys.path". If you should
so happen to have a 'qapi' package in your path, it will use *that*
package.

When we write "from .sibling import foo", we always reference explicitly
our sibling module; guaranteeing consistency in *where* we are importing
these modules from.

This can be useful when working with virtual environments and packages
in development mode. In development mode, a package is installed as a
series of symlinks that forwards to your same source files. The problem
arises because code quality checkers will follow "import qapi.x" to the
"installed" version instead of the sibling file and -- even though they
are the same file -- they have different module paths, and this causes
cyclic import problems, false positive type mismatch errors, and more.

It can also be useful when dealing with hierarchical packages, e.g. if
we allow qemu.core.qmp, qemu.qapi.parser, etc.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20201009161558.107041-6-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2020-10-10 11:37:47 +02:00
Peter Maydell
a69a6d4b4d scripts/qapi/parser.py: improve doc comment indent handling
Make the handling of indentation in doc comments more sophisticated,
so that when we see a section like:

Notes: some text
       some more text
          indented line 3

we save it for the doc-comment processing code as:

some text
some more text
   indented line 3

and when we see a section with the heading on its own line:

Notes:

some text
some more text
   indented text

we also accept that and save it in the same form.

If we detect that the comment document text is not indented as much
as we expect it to be, we throw a parse error.  (We don't complain
about over-indented sections, because for rST this can be legitimate
markup.)

The golden reference for the doc comment text is updated to remove
the two 'wrong' indents; these now form a test case that we correctly
stripped leading whitespace from an indented multi-line argument
definition.

We update the documentation in docs/devel/qapi-code-gen.txt to
describe the new indentation rules.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200925162316.21205-6-peter.maydell@linaro.org>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Whitespace between sentences tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2020-09-29 17:55:39 +02:00
Peter Maydell
99dff36d3a scripts/qapi: Move doc-comment whitespace stripping to doc.py
As we accumulate lines from doc comments when parsing the JSON, the
QAPIDoc class generally strips leading and trailing whitespace using
line.strip() when it calls _append_freeform().  This is fine for
Texinfo, but for rST leading whitespace is significant.  We'd like to
move to having the text in doc comments be rST format rather than a
custom syntax, so move the removal of leading whitespace from the
QAPIDoc class to the texinfo-specific processing code in
texi_format() in qapi/doc.py.

(Trailing whitespace will always be stripped by the rstrip() in
Section::append regardless.)

In a followup commit we will make the whitespace in the lines of doc
comment sections more consistently follow the input source.

There is no change to the generated .texi files before and after this
commit.

Because the qapi-schema test checks the exact values of the
documentation comments against a reference, we need to update that
reference to match the new whitespace.  In the first four places this
is now correctly checking that we did put in the amount of whitespace
to pass a rST-formatted list to the backend; in the last two places
the extra whitespace is 'wrong' and will go away again in the
following commit.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200925162316.21205-5-peter.maydell@linaro.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2020-09-29 17:55:39 +02:00
Markus Armbruster
dcdc07a97c qapi: Make section headings start a new doc comment block
Our current QAPI doc-comment markup allows section headers (introduced
with a leading '=' or '==') anywhere in a free-form documentation
comment.  This works for Texinfo because the generator simply prints a
Texinfo section command at that point in the output stream.  For rST
generation, since we're assembling a tree of docutils nodes, this is
awkward because a new section implies starting a new section node at
the top level of the tree and generating text into there.

Make section headers start a new free-form documentation block, so the
future rST document generator doesn't have to look at every line in
free-form blocks and handle headings in odd places.

This change makes no difference to the generated Texinfo.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200320091805.5585-3-armbru@redhat.com>
2020-09-07 16:35:16 +02:00
Markus Armbruster
d98884b75d qapi: Reject section markup in definition documentation
Section markup in definition documentation makes no sense and can
produce invalid Texinfo.  Reject.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200320091805.5585-2-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-09-07 16:35:16 +02:00
Markus Armbruster
8ec0e1a4e6 qapi: Brush off some (py)lint
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200304155932.20452-5-armbru@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2020-03-05 09:24:11 +01:00
Markus Armbruster
2cae67bcb5 qapi: Use super() now we have Python 3
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200304155932.20452-4-armbru@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2020-03-05 09:24:11 +01:00
Markus Armbruster
ed39c03e2f qapi: Drop conditionals for Python 2
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200304155932.20452-3-armbru@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2020-03-05 09:24:11 +01:00
Markus Armbruster
baa310f1bb qapi: Inheriting from object is pointless with Python 3, drop
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200304155932.20452-2-armbru@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2020-03-05 09:24:11 +01:00
Markus Armbruster
e151941d1b qapi: Check feature documentation against the schema
Commit f3ed93d545 "qapi: Allow documentation for features" neglected
to check documentation against the schema.  Fix that: check them the
same way we check arguments.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191024110237.30963-20-armbru@redhat.com>
2019-10-29 07:35:16 +01:00
Markus Armbruster
e4def78755 qapi: Polish reporting of bogus member documentation
Improve error messages from

    the following documented members are not in the declaration: a
    the following documented members are not in the declaration: aa, bb

to the more concise

    documented member 'a' does not exist
    documented members 'aa', 'bb' do not exist

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191024110237.30963-19-armbru@redhat.com>
2019-10-29 07:35:16 +01:00
Markus Armbruster
e6c42b96b9 qapi: Split up scripts/qapi/common.py
The QAPI code generator clocks in at some 3100 SLOC in 8 source files.
Almost 60% of the code is in qapi/common.py.  Split it into more
focused modules:

* Move QAPISchemaPragma and QAPISourceInfo to qapi/source.py.

* Move QAPIError and its sub-classes to qapi/error.py.

* Move QAPISchemaParser and QAPIDoc to parser.py.  Use the opportunity
  to put QAPISchemaParser first.

* Move check_expr() & friends to qapi/expr.py.  Use the opportunity to
  put the code into a more sensible order.

* Move QAPISchema & friends to qapi/schema.py

* Move QAPIGen and its sub-classes, ifcontext,
  QAPISchemaModularCVisitor, and QAPISchemaModularCVisitor to qapi/gen.py

* Delete camel_case(), it's unused since commit e98859a9b9 "qapi:
  Clean up after recent conversions to QAPISchemaVisitor"

A number of helper functions remain in qapi/common.py.  I considered
moving the code generator helpers to qapi/gen.py, but decided not to.
Perhaps we should rewrite them as methods of QAPIGen some day.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20191018074345.24034-7-armbru@redhat.com>
[Add "# -*- coding: utf-8 -*-" lines]
2019-10-22 13:53:55 +02:00