The old parser now has the correct name "Evaluator", so the
ParserFactory name was outdated. Additionally, the plan is to create a
new RuleChecker class, acting as a facade for the different
parsing-related stages (lexer, parser, evaluator, etc.), which is what
most if not all callers should use. The RuleCheckerFactory still returns
a FilterEvaluator for now.
Also, "Parser" is a specific term defining *how* things happen
internally, whereas "RuleChecker" describes *what* callers should expect
from the new class.
Change-Id: I25b47a162d933c1e385175aae715ca38872b1442
Remove unnecessary setters, injecting everything in the constructor.
These were leftovers from before the introduction of ParserFactory.
Remove public access to the conds used, include the information inside
the returned ParserStatus instead, and consequently simplify callers.
Change-Id: I0a30e044877c6c858af3ff73f819d5ec7c4cc769
This commit adds a class AFPSyntaxChecker which can statically analyze
a filter code to detect the following errors:
- unbound variables (which comes in two modes: conservative and liberal,
default to conservative)
- unused variables (disabled by default for compatibilty)
- assignment on built-in identifiers
- function application's arity mismatch
- function application's invalid function name
- non-string literal in the first argument of set / set_var
The existing parser and evaluator are modified as follows:
- The new (caching) evaluator no longer needs to perform variable
hoisting at runtime.
- Note that for array assignment, this changes the semantics.
- The new parser is more lenient, reducing parsing errors.
The static analyzer will catch these errors instead, allowing us
to give a much better error message and reduces the complexity of
the parser.
* The parser now allows function name to be any identifier.
* The parser now allows arity mismatch to occur.
* The parser now allows the first argument of set to be any expression.
Concretely, obvious changes that users will see are:
1. a := [1]; false & (a[] := 2); a[0] === 1
would evaluate to true, while it used to evaluate to the undefined value
due to hoisting
2. f(1)
will now error with 'f is not a valid function' as opposed to
'Unexpected "T_BRACE"'
3. length
will now error with 'Illegal use of built-in identifier "length"'
as opposed to 'Expected a ('
Appendix: conservative and liberal mode
The conservative mode is completely compatible with the current evaluator.
That is,
false & (a := 1); a
will not deem `a` as unbound, though this is actually undesirable because
`a` would then be bound to the troublesome undefined value.
The liberal mode rejects the above pattern by deeming `a` as unbound.
However, it also rejects
true & (a := 1); a
even though (a := 1) is always executed. Since there are several filters
in Wikimedia projects that rely on this behavior, we default the mode
to conservative for now.
Note that even the liberal mode doesn't really respect lexical scope
appeared in some other programming languages (see also T234690).
For instance:
(if true then (a := 1) else (a := 2) end); a
would be accepted by the liberal checker, even though under lexical scope,
`a` would be unbound. However, it is unlikely that lexical scope
will be suitable for the filter language, as most filters in
Wikimedia projects that have user-defined variable do violate lexical scope.
Bug: T260903
Bug: T238709
Bug: T237610
Bug: T234690
Bug: T231536
Change-Id: Ic6d030503e554933f8d220c6f87b680505918ae2
Create a dedicated "Exception" sub-namespace and remove the "AFP"
prefix, a leftover from the pre-namespace era.
Change-Id: I7e5fded9316d8b7d1628bc1a6ba8b1879ac901e1
All methods were moved to the new parser. Tests and other pieces were
adjusted to expect just a single parser. There are still some TODOs
(remove AFPTransitionBase, remove $this->mCur), but these are left for
another commit.
Note that the new parser was not renamed: this is because the names are
wrong anyway (CachingParser is more of an Evaluator than a Parser, and
AFPTreeParser is the real parser, and should be renamed as well).
NOTE to reviewers: this patch looks quite big, but if you diff the old
parser with the new version of the CachingParser, you'll notice that the
diff is actually small, since everything was basically copied verbatim.
Bug: T239990
Change-Id: Ie914ef64c70503a201b4d2dec698ca2fa8e69b10
In I63d9807264d7e2295afef51fc9d982447f92fcbd we are
changing how the permission checks are applied for revision,
so it uses passed User instance as Authority. However, when
user is mocked, the tests are breaking since the new user methods
are not mocked. Pass a real user for now to fix the test. Once
Authority reaches maturity and is ok to use in extensions, the
test should be rewritten to use authority directly.
Bug: T271458
Change-Id: Iacab813b253cc6e1439007e573e8ace06645860f
In particular, this brings stronger typing for getID(), and we can get
rid of many phan suppressions.
Change-Id: Icbf3a6f7db8105082646ec227f62c09449fb165d
Code change: in buildVarDumpTable remove special-cased null value. This
was used to avoid passing null to Html::element, but is no longer
necessary, since we now pretty-print the value.
Change-Id: I6180f6c53448d2a8c8c6066f222e9fd9df577554
This makes VariableHolder a true value object, and introduces a
stateless service, VariableManager, to operate on it.
Note, in theory, this new service is still cyclically coupled with
LazyVariableComputed. However, it's now two stateless service being
coupled, not two smart/god value objects, so we've still earned
something. For now, the dependency is hidden by using a callback. Some
alternatives for that are mentioned in a code comment.
Bug: T261069
Change-Id: I2f2c84c8e91472ba36084a8bbb4a923f6e04354b
This is an important step towards removing the AbuseFilter class. Note:
proposals for the name of the new service are welcome.
Change-Id: Ib4632173f728b1bdafadef96e01645a833bfceaa
Move to 'integration' all tests that are meant to stay there. Move
SaveTest outside because, while we might want to finalize it as an
integration test, some parts can still be moved to a unit test.
Change-Id: Id4b6deaac6875fdd85eebbebf0c5fb952d1fbb06
Just moving code around. Without a unit test because DI
coverage of change tags in core isn't available yet.
Change-Id: Iac861e1e24dae13581b8d9173357a1d6c94be88a
This moves a lot of things away from the AbuseFilter class. There's a
nasty static dependency on ChangeTags, but it's very limited anyway, and
it's going to be fixed once T245964 is resolved.
Change-Id: Ia7df4b4d3289c2722323f59ceecf3fdd38277785
