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>
It's already treated as optional, with one direct caller and some
subclass callers passing 'None'. Make it officially optional, which
requires moving the position of the argument to come after all required
parameters.
QAPISemError becomes functionally identical to QAPISourceError. Keep the
name to preserve its semantic meaning and avoid code churn, but remove
the now-useless __init__ wrapper.
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210421192233.3542904-4-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Rename QAPIError to QAPISourceError, and then create a new QAPIError
class that serves as the basis for all of our other custom exceptions,
without specifying any class properties.
This leaves QAPIError as a package-wide error class that's suitable for
any current or future errors.
(Right now, we don't have any errors that DON'T also want to specify a
Source location, but this MAY change. In these cases, a common abstract
ancestor would be desired.)
Add docstrings to explain the intended function of each error class.
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210421192233.3542904-2-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
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>
NB: The type aliases (SchemaInfo et al) declare intent for some of the
"dictly-typed" objects we pass around in introspect.py. They do not
enforce the shape of those objects, and cannot, until Python 3.7 or
later. (And even then, it may not be "worth it".)
Annotations are also added to the QAPISchemaEntity __init__ method in
schema.py to allow mypy to statically prove the type of typ.name,
needed to prove the return type of
QAPISchemaGenIntrospectVisitor._use_type().
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210216021809.134886-15-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Note on QAPISchemaEntity.__init__() squashed into commit message,
Comment wrapped to conform to PEP 8]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Use a constant to make it obvious we're referring to a very specific thing.
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210201193747.2169670-11-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Use './builtin' as the built-in module name instead of
None. Clarify the typing that this is now always a string.
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210201193747.2169670-9-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Define what a module is and define what kind of a module it is once and
for all, in one place.
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210201193747.2169670-6-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Fix a minor typing issue, and then establish a mypy type-checking
baseline.
Like pylint, this should be run from the folder above:
> mypy --config-file=qapi/mypy.ini qapi/
This is designed and tested for mypy 0.770 or greater.
Signed-off-by: John Snow <jsnow@redhat.com>
Tested-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Tested-by: Cleber Rosa <crosa@redhat.com>
Message-Id: <20201009161558.107041-19-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
At this point, that just means using a consistent strategy for constant names.
constants get UPPER_CASE and names not used externally get a leading underscore.
As a preference, while renaming constants to be UPPERCASE, move them to
the head of the file. Generally, it's nice to be able to audit the code
that runs on import in one central place.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-Id: <20201009161558.107041-13-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Petty style guide fixes and line length enforcement. Not a big win, not
a big loss, but flake8 passes 100% on the qapi module, which gives us an
easy baseline to enforce hereafter.
A note on the flake8 exception: flake8 will warn on *any* bare except,
but pylint's is context-aware and will suppress the warning if you
re-raise the exception.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-Id: <20201009161558.107041-9-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
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>
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>
This patch adds a new 'coroutine' flag to QMP command definitions that
tells the QMP dispatcher that the command handler is safe to be run in a
coroutine.
The documentation of the new flag pretends that this flag is already
used as intended, which it isn't yet after this patch. We'll implement
this in another patch in this series.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20201005155855.256490-9-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Unlike regular feature flags, the new special feature flag
"deprecated" is recognized by the QAPI generator. For now, it's only
permitted with commands, events, and struct members. It will be put
to use shortly.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200317115459.31821-26-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Doc typo fixed]
The .connect_doc() of classes that have QAPISchemaMember connect them
to their documentation. Change them to delegate the actual work to
new QAPISchemaMember.connect_doc(). Matches the .connect_doc() that
already exist.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200317115459.31821-20-armbru@redhat.com>
QAPISchemaObjectTypeVariants represents both object type and alternate
type variants. Rename to QAPISchemaVariants.
Rename QAPISchemaObjectTypeVariant the same way.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200317115459.31821-19-armbru@redhat.com>
Move QAPISchemaAlternateType up some, so that all QAPISchemaFOOType
are together. Move QAPISchemaObjectTypeVariants right behind its
users.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200317115459.31821-18-armbru@redhat.com>
QAPISchema._make_features() takes a definition expression, and
extracts its 'features' member. The other ._make_FOO() leave
destructuring expressions to their callers. Change ._make_features()
to match them.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200317115459.31821-17-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
In v4.1.0, we added feature flags just to struct types (commit
6a8c0b5102^..f3ed93d545), to satisfy an immediate need (commit
c9d4070991 "file-posix: Add dynamic-auto-read-only QAPI feature"). In
v4.2.0, we added them to commands (commit 23394b4c39 "qapi: Add
feature flags to commands") to satisfy another immediate need (commit
d76744e65e "qapi: Allow introspecting fix for savevm's cooperation
with blockdev").
Add them to the remaining definitions: enumeration types, union types,
alternate types, and events.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200317115459.31821-13-armbru@redhat.com>
QAPISchemaEntity calls doc.connect_feature() in .check(). Improper
since commit ee1e6a1f6c split .connect_doc() off .check(). Move the
call. Requires making the children call super().connect_doc() as they
should.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200317115459.31821-12-armbru@redhat.com>
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>
Recent commit 3e7fb5811b "qapi: Fix code generation for empty modules"
modules" switched QAPISchema.visit() from
for entity in self._entity_list:
effectively to
for mod in self._module_dict.values():
for entity in mod._entity_list:
Visits in the same order as long as .values() is in insertion order.
That's the case only for Python 3.6 and later. Before, it's in some
arbitrary order, which results in broken generated code.
Fix by making self._module_dict an OrderedDict rather than a dict.
Fixes: 3e7fb5811b
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Thomas Huth <thuth@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: BALATON Zoltan <balaton@eik.bme.hu>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20200116202558.31473-1-armbru@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
When a sub-module doesn't contain any definitions, we don't generate
code for it, but we do generate the #include.
We generate code only for modules that get visited.
QAPISchema.visit() visits only modules that have definitions. It can
visit modules multiple times.
Clean this up as follows. Collect entities in their QAPISchemaModule.
Have QAPISchema.visit() call QAPISchemaModule.visit() for each module.
Have QAPISchemaModule.visit() call .visit_module() for itself, and
QAPISchemaEntity.visit() for each of its entities. This way, we visit
each module exactly once.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191120182551.23795-6-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Modules are represented only by their names so far. Introduce class
QAPISchemaModule. So far, it merely wraps the name. The next patch
will put it to more interesting use.
Once again, arrays spice up the patch a bit. For any other type,
@info points to the definition, which lets us map from @info to
module. For arrays, there is no definition, and @info points to the
first use instead. We have to use the element type's module instead,
which is only available after .check().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191120182551.23795-5-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191120182551.23795-2-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
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>
Commit 6a8c0b5102 "qapi: Add feature flags to struct types" added
features to QAPISchemaObjectType. Commit a95daa5093 "qapi: Add
feature flags to commands in qapi" added them to QAPISchemaCommand,
duplicating the code. Tolerable, but the duplication will only get
worse as we add features to more definitions.
To de-duplicate, lift features from QAPISchemaObjectType and
QAPISchemaCommand into QAPISchemaEntity.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191024110237.30963-18-armbru@redhat.com>
All sub-classes of QAPISchemaEntity now override .check_doc() the same
way, except for QAPISchemaType and and QAPISchemaArrayType.
Put the overrides' code in QAPISchemaEntity.check_doc(), and drop the
overrides. QAPISchemaType doesn't care because it's abstract.
QAPISchemaArrayType doesn't care because its .doc is always None.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191024110237.30963-14-armbru@redhat.com>
All callers now pass doc=None. Drop the argument.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191024110237.30963-13-armbru@redhat.com>
When a command's 'data' is an object, its doc comment describes the
arguments defined there. When 'data' names a type, the doc comment
does not describe arguments. Instead, the doc generator inserts a
pointer to the named type.
An event's doc comment works the same.
We don't actually check doc comments for commands and events.
Instead, QAPISchema._def_command() forwards the doc comment to the
implicit argument type, where it gets checked. Works because the
check only cares for the implicit argument type's members.
Not only is this needlessly hard to understand, it actually falls
apart in two cases:
* When 'data' is empty, there is nothing to forward to, and the doc
comment remains unchecked. Demonstrated by test doc-bad-event-arg.
* When 'data' names a type, we can't forward, as the type has its own
doc comment. The command or event's doc comment remains unchecked.
Demonstrated by test doc-bad-boxed-command-arg.
The forwarding goes back to commit 069fb5b250 "qapi: Prepare for
requiring more complete documentation", put to use in commit
816a57cd6e "qapi: Fix detection of bogus member documentation". That
fix was incomplete.
To fix this, make QAPISchemaCommand and QAPISchemaEvent check doc
comments, and drop the forwarding of doc comments to implicit argument
types.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191024110237.30963-12-armbru@redhat.com>
An object type's doc comment describes the type's members, less the
ones defined in a named base type. Cases:
* Struct: the members are defined in 'data' and inherited from 'base'.
Since the base type cannot be implicit, the doc comment describes
just 'data'.
* Simple union: the only member is the implicit tag member @type, and
the doc comment describes it.
* Flat union with implicit base type: the members are defined in
'base', and the doc comment describes it.
* Flat union with named base type: the members are inherited from
'base'. The doc comment describes no members.
Before we can check a doc comment with .check_doc(), we need
.connect_doc() connect each of its "argument sections" to the member
it documents.
For structs and simple unions, this is straightforward: the members in
question are in .local_members, and .connect_doc() connects them.
For flat unions with a named base type, it's trivial: .local_members
is empty, and .connect_doc() does nothing.
For flat unions with an implicit base type, it's tricky. We have
QAPISchema._make_implicit_object_type() forward the union's doc
comment to the implicit base type, so that the base type's
.connect_doc() connects the members. The union's .connect_doc() does
nothing, as .local_members is empty.
Dirt effect: we check the doc comment twice, once for the union type,
and once for the implicit base type.
This is needlessly brittle and hard to understand. Clean up as
follows. Make the union's .connect_doc() connect an implicit base's
members itself. Do not forward the union's doc comment to its
implicit base type.
Requires extending .connect_doc() so it can work with a doc comment
other than self.doc. Add an optional argument for that.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191024110237.30963-11-armbru@redhat.com>
Enumeration type documentation comments are not checked, as
demonstrated by test doc-bad-enum-member. This is because we neglect
to call self.doc.check() for enumeration types. Messed up in
816a57cd6e "qapi: Fix detection of bogus member documentation". Fix
it.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191024110237.30963-10-armbru@redhat.com>
Splitting documentation checking off the .check() methods makes them a
bit more focused, which is welcome, as some of them are pretty big.
It also prepares the ground for the following commits.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191024110237.30963-9-armbru@redhat.com>
Similarly to features for struct types introduce the feature flags also
for commands. This will allow notifying management layers of fixes and
compatible changes in the behaviour of a command which may not be
detectable any other way.
The changes were heavily inspired by commit 6a8c0b5102.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20191018081454.21369-3-armbru@redhat.com>
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]
