Commit Graph

9 Commits

Author SHA1 Message Date
Markus Armbruster f01338cce6 qapi: Speed up frontend tests
"make check-qapi-schema" takes around 10s user + system time for me.
With -j, it takes a bit over 3s real time.  We have worse tests.  It's
still annoying when you work on the QAPI generator.

Some 1.4s user + system time is consumed by make figuring out what to
do, measured by making a target that does nothing.  There's nothing I
can do about that right now.  But let's see what we can do about the
other 8s.

Almost 7s are spent running test-qapi.py for every test case, the rest
normalizing and diffing test-qapi.py output.  We have 190 test cases.

If I downgrade to python2, it's 4.5s, but python2 is a goner.

Hacking up test-qapi.py to exit(0) without doing anything makes it
only marginally faster.  The problem is Python startup overhead.

Our configure puts -B into $(PYTHON).  Running without -B is faster:
4.4s.

We could improve the Makefile to run test cases only when the test
case or the generator changed.  But I'm after improvement in the case
where the generator changed.

test-qapi.py is designed to be the simplest possible building block
for a shell script to do the complete job (it's actually a Makefile,
not a shell script; no real difference).  Python is just not meant for
that.  It's for bigger blocks.

Move the post-processing and diffing into test-qapi.py, and make it
capable of testing multiple schema files.  Set executable bits while
there.

Running it once per test case now takes slightly longer than 8s.  But
running it once for all of them takes under 0.2s.

Messing with the Makefile to run it only on the tests that need
retesting is clearly not worth the bother.

Expected error output changes because the new normalization strips off
$(SRCDIR)/tests/qapi-schema/ instead of just $(SRCDIR)/.

The .exit files go away, because there is no exit status to test
anymore.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20191018074345.24034-5-armbru@redhat.com>
2019-10-22 09:26:12 +02:00
Markus Armbruster eeb57c85da qapi: Avoid redundant definition references in error messages
Many error messages refer to the offending definition even though
they're preceded by an "in definition" line.  Rephrase them.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190927134639.4284-22-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2019-09-28 17:17:32 +02:00
Markus Armbruster 2ab218aad6 qapi: Change frontend error messages to start with lower case
Starting error messages with a capital letter complicates things when
text can get interpolated both at the beginning and in the middle of
an error message.  The next patch will do that.  Switch to lower case
to keep it simpler.

For what it's worth, the GNU Coding Standards advise the message
"should not begin with a capital letter when it follows a program name
and/or file name, because that isn’t the beginning of a sentence. (The
sentence conceptually starts at the beginning of the line.)"

While there, avoid breaking lines containing multiple arguments in the
middle of an argument.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20190927134639.4284-7-armbru@redhat.com>
2019-09-28 17:17:18 +02:00
Markus Armbruster 7be6c51194 qapi: Prefix frontend errors with an "in definition" line
We take pains to include the offending expression in error messages,
e.g.

    tests/qapi-schema/alternate-any.json:2: alternate 'Alt' member 'one' cannot use type 'any'

But not always:

    tests/qapi-schema/enum-if-invalid.json:2: 'if' condition must be a string or a list of strings

Instead of improving them one by one, report the offending expression
whenever it is known, like this:

    tests/qapi-schema/enum-if-invalid.json: In enum 'TestIfEnum':
    tests/qapi-schema/enum-if-invalid.json:2: 'if' condition must be a string or a list of strings

Error messages that mention the offending expression become a bit
redundant, e.g.

    tests/qapi-schema/alternate-any.json: In alternate 'Alt':
    tests/qapi-schema/alternate-any.json:2: alternate 'Alt' member 'one' cannot use type 'any'

I'll take care of that later in this series.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20190927134639.4284-5-armbru@redhat.com>
2019-09-28 17:17:18 +02:00
Markus Armbruster f03255362a qapi: Permit alternates with just one branch
A union or alternate without branches makes no sense and doesn't work:
it can't be instantiated.  A union or alternate with just one branch
works, but is degenerate.  We accept the former, but reject the
latter.  Weird.  docs/devel/qapi-code-gen.txt doesn't mention the
difference.  It claims an alternate definition is "is similar to a
simple union type".

Permit degenerate alternates to make them consistent with unions.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20190913201349.24332-10-armbru@redhat.com>
2019-09-24 14:07:22 +02:00
Markus Armbruster 87c16dceca qapi: Back out doc comments added just to please qapi.py
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>
2017-03-16 07:13:01 +01:00
Marc-André Lureau 3313b6124b qapi: add qapi2texi script
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>
2017-01-16 10:10:35 +01:00
Eric Blake 02a57ae32b qapi: Forbid empty unions and useless alternates
Empty unions serve no purpose, and while we compile with gcc
which permits them, strict C99 forbids them.  We happen to inject
a dummy 'void *data' member into the C unions that represent QAPI
unions and alternates, but we want to get rid of that member (it
pollutes the namespace for no good reason), which would leave us
with an empty union if the user didn't provide any branches.  While
empty structs make sense in QAPI, empty unions don't add any
expressiveness to the QMP language.  So prohibit them at parse
time.  Update the documentation and testsuite to match.

Note that the documentation already mentioned that alternates
should have "two or more JSON data types"; so this also fixes
the code to enforce that.  However, we have existing uses of a
union type with only one branch, so the 2-or-more strictness
is intentionally limited to alternates.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-3-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-19 11:08:56 +01:00
Eric Blake 8d25dd101f qapi: Add tests for empty unions
The documentation claims that alternates are useful for
allowing two or more types, although nothing enforces this.
Meanwhile, it is silent on whether empty unions are allowed.
In practice, the generated code will compile, in part because
we have a 'void *data' branch; but attempting to visit such a
type will cause an abort().  While there's no technical reason
that a degenerate union could not be made to work, it's harder
to justify the time spent in chasing known (the current
abort() during visit) and unknown corner cases, than it would
be to just outlaw them.  A future patch will probably take the
approach of forbidding them; in the meantime, we can at least
add testsuite coverage to make it obvious where things stand.

In addition to adding tests to expose the problems, we also
need to adjust existing tests that are meant to test something
else, but which could fail for the wrong reason if we reject
degenerate alternates/unions.

Note that empty structs are explicitly supported (for example,
right now they are the only way to specify that one branch of a
flat union adds no additional members), and empty enums are
covered by the testsuite as working (even if they do not seem
to have much use).

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1443565276-4535-8-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-10-12 18:44:54 +02:00