Summary: This diff implements this for Field Not Initialized check
Reviewed By: artempyanykh
Differential Revision: D19393989
fbshipit-source-id: cf60e8d53
Summary:
This diff does it for nullable dereference and assignment violations
rules which happen under NullsafeStrict case.
Follow up are to make the same for inheritance and field initializer
violations.
Possible follow up includes making error message more specific and
articulare this this is a nullsafe strict mode.
Reviewed By: artempyanykh
Differential Revision: D19392916
fbshipit-source-id: 2554ac7a7
Summary:
The one with Object as the second param is in `com.facebook.common.internal`.
The one with String as the second param is in `com.facebook.common.preconditions`.
(Don't ask :) )
Reviewed By: artempyanykh
Differential Revision: D19087334
fbshipit-source-id: ba02c9101
Summary:
According to Java semantics, they are always non-null.
Internally they are represented as static fields, so they have
DeclaredNonnull nullability, which means NullsafeStrict mode would
refuse to use them without strictification.
Lets teach nullsafe that these guys are non-nullables.
See also FN in test case.
Reviewed By: ngorogiannis
Differential Revision: D19024547
fbshipit-source-id: 8c120fa50
Summary:
- Remove `to_flat_string` as there is `get_field_name` that unambiguously does the same thing.
- Make `pp` print only the field in all languages.
- Fix `to_full_string` so that it has unified behaviour across java/clang and so that it doesn't print `class Foo.x`, but rather `Foo.x`.
Reviewed By: ezgicicek
Differential Revision: D18963033
fbshipit-source-id: e2c803c7d
Summary:
Remove Clang and Java submodules of Typ.Fieldname. They are unnecessary and they reflect a fake dichotomy: there is only one fieldname type. To distinguish between fields of Java classes and other C constructs, there is a helper function provided, but the idea is simple: obtain the class type the field belongs to, and check if it's a Java class.
This diff still preserves behaviour, but removes as many functions as possible from the interface, to leave a small surface.
Reviewed By: mityal
Differential Revision: D18962423
fbshipit-source-id: ffe6933ee
Summary:
For now lets support the simplest form: "//"-style comments.
Having comments is useful:
1. It serves as documentation for API.
2. It serves as justification of why such and such method or param is
nullable or not (so the future readers can understand the reasoning of
the person who added the signature).
Reviewed By: artempyanykh
Differential Revision: D18762289
fbshipit-source-id: 90c515ea8
Summary:
This diff enables parsing and auto-formatting documentation
comments (aka docstrings).
I have looked at this entire diff and manually made some changes to
improve the formatting. In some cases it looked like it would take too
much time, or benefit from someone more familiar with the code doing
it, and I instead disabled auto-formatting docstrings in those files.
Also, there are some source files where the docstrings are invalid,
and some where the structure detected by the parser appears not to
match what was intended. Auto-formatting has been disabled for these
files.
Reviewed By: ezgicicek
Differential Revision: D18755888
fbshipit-source-id: 68d72465d
Summary:
We already have a number of `[pkg].Preconditions.checkNotNull`
modelled, but the one from `androidx` is missing yet widely used.
Reviewed By: mityal
Differential Revision: D18748550
fbshipit-source-id: 83d3317ae
Summary:
This will make our analysis more precise. E.g. in the future we can classify
"condition redundand" warnings by origin, and warn only for
InferredNonnull, or autogenerate fixes based on the origin.
Error messaging does not currently take into account origin for nonnull
types, but this can be changed in the future
Reviewed By: ngorogiannis
Differential Revision: D18685304
fbshipit-source-id: 6a1f263f5
Summary:
This will allow us tune nullsafe behavior in a more fine-grained way.
See e.g. a follow up diff when we report errors more clearly.
Reviewed By: ngorogiannis
Differential Revision: D18683747
fbshipit-source-id: 7b5c42a03
Summary:
We were wrongly not supressing third-party calls in
case third party repo is provided: there was a bug in the function is_modelled_externally.
because of this we accidentally stopped supressing third party and
started to advertise it in non-strict mode.
we do plan doing that, but little bit further ahead :)
So let's add a param guiding this.
Reviewed By: artempyanykh
Differential Revision: D18658271
fbshipit-source-id: 703f2675b
Summary:
We will migrate to the new representation in the future, but for now
let's keep both active.
Reviewed By: artempyanykh
Differential Revision: D18657955
fbshipit-source-id: 9deb03f1f
Summary:
Now we point to the root cause of the problem, and also provide
actionable way to solve the issue
Reviewed By: artempyanykh
Differential Revision: D18575650
fbshipit-source-id: ba4884fe1
Summary:
Two goals:
1. Be less assertive when speaking about third party code (it might be
written with different conventions).
2. Point to third party signatures folder so the users know how to
proceed
Reviewed By: artempyanykh
Differential Revision: D18571514
fbshipit-source-id: 854d6e746
Summary:
1/ We now support messaging for third-party: show file name and line
number
2/ We did not show information about internal models in case of param
calls
3/ Small change: we don't specify "modelTables.ml" anymore: no need to
expose implementation details
Reviewed By: artempyanykh
Differential Revision: D18569790
fbshipit-source-id: 28586c8ff
Summary:
In the follow up diff we will use it to render more informative
error message when type error is relevant to the fact that the code is
third-party
Reviewed By: artempyanykh
Differential Revision: D18569783
fbshipit-source-id: 4f6dcc404
Summary:
Let the functions return the modified storage, not unit.
It will play nicely with the next diff, which will add more data to
storage which will be non-mutable.
Reviewed By: artempyanykh
Differential Revision: D18569768
fbshipit-source-id: ade5685be
Summary:
Whole bunch of changes aimed to make error messages more clear and
concise.
1/ Wording and language is unified. We make errors sound more like a
type system violations, rather than linter reccomendations.
Particularly, we refrain from saying things like "may be null" - this is
a linter-style statement that may provoke discussions (what if the
developer knows it can not be null in this particular case).
Instead, we refer to declared nullability and nullability of actual values. This way, it is more clear that this is not a heuristic, this is how rules of a type-system work.
2/ Additionally, we drop things like field class in places when the
context should be clear by who looks at the error. We expect the user
sees the code and the error caption. So e.g. we don't repeat the word "field"
twice.
3/ In cases when we are able to retrieve formal param name, we include it for
usability.
4/ For Field not initialized error, we refer to Initializer methods:
this is a non-obvious but important nullsafe feature.
Reviewed By: artempyanykh
Differential Revision: D18569762
fbshipit-source-id: 9221d7102
Summary:
It make the message bit less heavy, and also it is kind of obvious that
it is origin.
In follow up diffs we will change the text so it is hopefully even more
obvious.
Reviewed By: artempyanykh
Differential Revision: D18527695
fbshipit-source-id: a305d547b
Summary:
1. We don't want to teach the users to ignore noise origin because
sometimes we are going to render something useful for them.
2. It just looks not cool.
Reviewed By: artempyanykh
Differential Revision: D18527694
fbshipit-source-id: 0ea248122
Summary:
This diff also removes clumsy typeErr.origin_desc and improves interface
of TypeOrigin.
This will allow to render smarter error message, depending on the
context (see follow up diff).
Reviewed By: ngorogiannis
Differential Revision: D18527692
fbshipit-source-id: b7eb11db8
Summary:
This diff is a part of work teaching Nullsafe to explain decisions it's
making.
We used to use default for this, which is both buggy and hard to
diagnose. Now we explicitly document nullsafe behaviour in this case.
Reviewed By: artempyanykh
Differential Revision: D18481220
fbshipit-source-id: 0b0cf8b38
Summary:
This diff is a part of work teaching Nullsafe to explain decisions it's
making.
This method was the last escape hatch for InferredNullability to
misreport about its origin.
Now each time we change nullability we provide origin that is consistent
with the nullability itself.
Reviewed By: artempyanykh
Differential Revision: D18453567
fbshipit-source-id: 3d9b7fa2e
Summary:
This is one of key diff in this refactoring stack.
Previously, we used to set nullability independently of type origin,
which opened doors for inconsistent states, bugs, and overcomplicated
code.
Now we have just two method left:
1. `create` -> the main one, yay
2. `set_nonnull` -> will get rid of this in the next diff.
Reviewed By: artempyanykh
Differential Revision: D18451950
fbshipit-source-id: edc485709
Summary:
This diff is a part of work teaching Nullsafe to explain decisions it's
making.
In this diff, we merely rename the value to clearly reflect its currect
usage.
In follow up diffs we are going to make usages of this instance more
restricted and concentrate them in several places in the code.
Reviewed By: artempyanykh
Differential Revision: D18451290
fbshipit-source-id: cf3773364
Summary:
This diff is a part of work teaching Nullsafe to explain decisions it's
making.
1. `Formal` was bit cryptic name.
2. Splitting method param and this makes a lot of sense. It is almost an
implementation detail that hey happen to come from "param" in the
method's signature.
3. Apart from others, this diff fixes a minor bug - we used to treat
this as DeclaredNonnull, which (in future) means suppressing legit warnings
like condition redundant. This would be an issue if we were to start
showing "high confidence" condition redundant warnings.
Reviewed By: ngorogiannis
Differential Revision: D18451294
fbshipit-source-id: acc295e3f
Summary:
This diff is a part of work teaching Nullsafe to explain decisions it's
making.
1. Make Field origin a record: consistent with Proc; more readable; will
add more elements in follow up diffs.
2. `Proc` is bit ambiguous: it is unclear if this is a method call result or param.
Let's make it clear that it is the result of a method call.
Reviewed By: ngorogiannis
Differential Revision: D18450188
fbshipit-source-id: c5abae3ad
Summary:
This diff is a part of work teaching Nullsafe to explain decisions it's
making.
Using `New` was definitely not a good idea here, we need a specific
data type value here.
Reviewed By: artempyanykh
Differential Revision: D18450174
fbshipit-source-id: 7ce7cc7e8
Summary:
This diff is a part of work teaching Nullsafe to explain decisions it's
making.
Introducing more specific origins will allow us to automatically infer
nullability based on type origin (in follow up diffs).
Reviewed By: ngorogiannis
Differential Revision: D18450165
fbshipit-source-id: 9dc0d25c0
Summary:
`typecheck_instr` is a function that essentially does most of nullsafe typechecking
work: it pattern matches the instruction and handles most of business logic (e.g. knowledge about builtins, rules of PropagatesNullable, flow-sensitive rule for condition branches etc etc etc.
This is a gigantic function consisting of huge amount of nested
function. No way it can fit in someone's head and it is super hard to
read. It also captures many things like node and node'.
This diff does fairly shallow work:
1. Moves most of nested subfunctions into top-level functions. It also
means that what was previously hiddenly captured is now made an explicit
dependency.
2. Some (minority) of them are renamed to better indicate the context.
3. Some (minority) of params are renamed to clear indicate the
difference.
4. Some params are made named params, especially booleans and params
that have the same types so could be confused.
5. In some placed, added bit more clear comments.
This diff DOES NOT do:
1. Tries to fully resolve confusion between cryptic names. In couple of places, instead of node'
and node we use node and original_node, which is barely better. But we
still have ugly things like typestate and typestate1 leaving together.
Baby steps!
2. Tries to create better or consistent names in functions. I did it for
most obvious cases, that's it.
3. Order or params is arbitrary. I just used the order that was easy to
come up with, no consistency here.
Reviewed By: artempyanykh
Differential Revision: D18425965
fbshipit-source-id: 7a775f08d
Summary:
We still have few remaining places which we have a logic not encoded in
as a Nullability type. Ignoring third party param calls is one of them.
We don't want this behavior for strict mode.
Reviewed By: artempyanykh
Differential Revision: D18396639
fbshipit-source-id: dbfedc769
Summary:
This is a dirty hack to make nullsafe behave consistently for internal
and external models.
Medium term this code needs to be rewritten in a better way, so that we
pass all information in annotated signature (either in form of Inferred
nullability, or type origin, which tracks third party calls).
As a follow up, we will make reporting more clear.
Reviewed By: artempyanykh
Differential Revision: D18372660
fbshipit-source-id: 12c2449e1
Summary:
Ability to accept relative path is convenient for testing and local
debugging.
Ability to accept absolute paths is needed for buck integration - buck
knows absolute path (to properly invalidate cache when the content of
the folder is changed) and passes it to infer.
Reviewed By: artempyanykh
Differential Revision: D18370407
fbshipit-source-id: be7f12ae1
Summary: Follow ups will include error messaging that makes the choice clear
Reviewed By: artempyanykh
Differential Revision: D18347664
fbshipit-source-id: b6f005726
Summary:
In this diff, we just load the info from the storage. Next diff will be
actually using this information to infer nullability.
`ThirdPartyAnnotationGlobalRepo.get_repo` will be used in the next diff,
hence #skipdeadcode
Reviewed By: artempyanykh
Differential Revision: D18347647
fbshipit-source-id: 82a9223c6
Summary:
In next diffs, we will:
1/ teach nullsafe to read nullability information from the 3rd party
annotation folder
2/ use this storage in addition to our hard-coded
models to respect nullability during type-checking
Reviewed By: artempyanykh
Differential Revision: D18247538
fbshipit-source-id: ee45bc80e
Summary:
More rigid format for 3rd party annotation repo
To simplify external processing by tools, lets not accept any divergence from a
format, which is:
<fully qualified class name>#<method_name>(<params>)[ Nullable]
<params> = <list of param separated by ", ">
<param> = [Nullable ]<fully qualified type>
Particularly:
- Dont accept spaces in arbitrary places
- Require a single space after each comma separating params
- Require a single space between closing parethesis and nullable
annotation, if present
- Require at least one '.' in a class name (to prevent errors when
somebody did not specify a package).
This diff also makes error messaging more user-friendly, because now it
is easy to do a minor mistake like forget a space after comma.
Reviewed By: asm89
Differential Revision: D18297382
fbshipit-source-id: 91aab6823
Summary:
This is a helper module for reading info from a 3rd party nullability repository.
Next diffs are going to use it for reading nullability repository from
disk.
Reviewed By: artempyanykh
Differential Revision: D18225473
fbshipit-source-id: 06a2dc97e
Summary: The way `<=` is used in `AbstractDomain` prevents infix use and forces bracketing it everywhere. Replace with simple `leq`.
Reviewed By: jvillard
Differential Revision: D18201854
fbshipit-source-id: 8175224e4
Summary:
Primitive types are not annotated. Because of that, we used to implicitly derive
`DeclaredNonnull` type for them. This worked fine, but this leads to errors in Strict mode, which does
not believe DeclaredNonnull type.
Now lets offifically teach nullsafe that primitive types are
non-nullable.
Reviewed By: jvillard
Differential Revision: D18114623
fbshipit-source-id: 227217931
Summary:
The wrong function was used when we tried to see if the class is
annotated with NullsafeStrict. This made it work only for non-static
methods.
Now we use the proper way.
Reviewed By: ngorogiannis
Differential Revision: D18113848
fbshipit-source-id: 02b7555be
Summary: As suggested by artempyanykh, this will make it bit more clear
Reviewed By: artempyanykh
Differential Revision: D18037204
fbshipit-source-id: 65cb96815
Summary:
This is the first take on strict mode semantics.
The main invariant of strict mode is the following:
If the function passes `NullsafeStrict` check and its return value is
NOT annotated as Nullable, then the function does not indeed return
nulls, subject to unsoundness issues (which should either be fixed, or
should rarely happen in practice).
This invariant helps the caller in two ways:
1. Dangerous usages of non strict functions are visible, so the caller is enforced to check them (via assertions or conditions), or strictify them.
2. When the function is strict, the caller does not need to worry about
being defensive.
Biggest known issues so far:
1. Condition redundant and over-annotated warnings don't fully
respect strict mode, and this leads to stupid false positives. (There is
so much more stupid false positives in condition redundant anyway, so
not particularly a big deal for now).
2. Error reporting is not specific to mode. (E.g. we don't distinct real nullables and non-trusted non-nulls, which can be misleading). To be
improved as a follow up.
Reviewed By: artempyanykh
Differential Revision: D17978166
fbshipit-source-id: d6146ad71
Summary:
This is an intermediate nullability type powering future Strict mode.
See the next diff.
Reviewed By: artempyanykh
Differential Revision: D17977909
fbshipit-source-id: 2d5ab66d4
Summary:
Currently, we have NullsafeRules.ml responsible for detecting the
violation fact. All other logic: what should be the error type,
severity, and error message, is in TypeErr.ml.
In this diff, we move logic from NullsafeRules.ml and TypeErr.ml to
dedicated modules like AssignmentRule.ml etc.
Each such module is responsible for:
- detecting the violation fact (this is moved from NullsafeRules.ml)
- rendering the violation error (this is moved from TypeErr.ml).
This approach makes sense for two reasons:
1. The violation fact and the way we show error are logically related to
each other.
2. In future diffs, we will support more features guiding rule behavior,
such as a) decision whether to hide or show the error depending on type
information and mode; b) the way we render error depending on type
information and role.
Having dedicated modules incapsulating knowledge about rules is a natural way to support 2.
Reviewed By: artempyanykh
Differential Revision: D17977891
fbshipit-source-id: a53d916d3
Summary:
1. For each Nullsafe Rule, lets have a dedicated IssueType.
2. Split error reporting to three subfunctions: description, field type,
and infer issue.
This allows to introduce additional capabilities in a consolidated
manner. Example of such capabilities is should we hide or show an error,
what should be error severity depending on strictness mode, and how
exactly the error should be reported depending on how exactly
nullability is violated.
Reviewed By: artempyanykh
Differential Revision: D17977887
fbshipit-source-id: 860d67d2f
Summary:
This function can return `None` if the result is equal to the first
argument of join (why first?). It is unclear if it was an optimization
attempt of over-complicated logic.
Reviewed By: artempyanykh
Differential Revision: D17876561
fbshipit-source-id: 9628fb86e
Summary:
The goal of this logic is unclear:
1/ See the comments
2/ I can not see the scenario where classes and proper types can be
joined in a legit Java program
3/ Even it if was the case, I don't see how this heuristic is justified.
So I assume it is not.
Reviewed By: artempyanykh
Differential Revision: D17876568
fbshipit-source-id: c9c6cd604
Summary:
It is unclear what is the purpose of doing so, and it adds complexity to
codebase.
1/ The semantics of this is not clear, it more or less corresponds to
"where are all original locations that contributed to the type
calculation", but many branches in CFG have nothing to do with
nullability; also it was used not always consistently.
2/ The only place where this was used is logs, so this is no-ops. It is
unclear how seeing all locations can help debugging, given 3/ - see
below
3/ We have the right place to store such informatin, namely TypeOrigin,
where we store locations associated with types where we merge them in
CFG. Currently, we store only "winner" - the most relevant locations
that contributed to nullability in the most informative way. We show
this to the user when we report an error.
4/ If we want to support more things (e.g. show something more to the user), TypeOrigin
seems to be the right place. Or, alternatively, we might still merge
locations in `range`, but this will be better to organize in a tree form
instead of flat list that is not really informative and helpful. It is
all speculative though since need to support things like that seems
unclear.
Reviewed By: artempyanykh
Differential Revision: D17857198
fbshipit-source-id: 6cf6e48a2
Summary:
By some unfortunate logic, OCaml often decides to use
`sexp_list`/`sexp_option` instead of just `list`/`option`. Sometimes
these get copy/pasted in interface files.
It would be good to tell OCaml not to do that in the first place but in
the meantime: this diff.
Reviewed By: ngorogiannis
Differential Revision: D17907938
fbshipit-source-id: 7546834a2
Summary:
This diff proceeds work for consolidating nullsafe logic and making it
type-agnostic
Reviewed By: artempyanykh
Differential Revision: D17808485
fbshipit-source-id: 85356c625
Summary:
The current usage has several issues reducing code maintainability and
readability:
1. Null_field_access was misleading: it was used for checking accesing
to arrays as well!
2. But actually, when checking access to array via `length`, we sometimes
pretended it is a field access (hence very tricky code in rendering the
error).
3. "Call receiver consistency" is unclear name, was not obvious that it is all about
calling a method in an object.
Let's also consolidate code.
Reviewed By: artempyanykh
Differential Revision: D17789618
fbshipit-source-id: 9b0f58c9c
Summary:
This proceeds work on abstracting out operations requiring raw
nullability operations from infer core code. This will simplify coming
introducing of intermediate nullability levels
Reviewed By: artempyanykh
Differential Revision: D17789612
fbshipit-source-id: 9a2bea2ed
Summary:
In previous refactoring stages, we operated on AnnotatedNullability
(nullability of a field or method signature together with its origin),
and InferredNullability (nullability of a value in typestate together
with its origin).
Now it is time to extract common Nullability as a type system concept,
together with `<:` and `join` functionality. This was sketched in
`NullsafeRules`, so this diff consolidates this as well.
In follow up diffs, we will reduce/get rid of direct usages of things like
`InferredNullability.is_nullable`. This will simplify introducing
intermediate Nullability types.
Reviewed By: artempyanykh
Differential Revision: D17789599
fbshipit-source-id: f1b9d2dd0
Summary:
The documentation and uses of filtering disagree. One typical usage is deduplication.
Split that where obvious, add comments where not obvious, and leave alone when obviously unrelated to deduplication.
Reviewed By: mityal
Differential Revision: D17715329
fbshipit-source-id: ec757927b
Summary:
This is a preparation for coming introducing of Unknown nullability.
When this happens, a value will be able to be neither nullable, nor
non-nullable.
This will break many checks that implicitly assume "not nullable means non-null".
In this diff, we review all such checks and change them accordingly.
Reviewed By: artempyanykh
Differential Revision: D17600177
fbshipit-source-id: c38d87175
Summary:
It took a while for me to figure out what does this method do; the
reasons were:
1. a lot of names were cryptic and/or misleading
2. because everything is inline one needs to read everything to figure
out what is going on here.
So this diff changes the names a bit and moves some of methods outside.
This is still far not perfect, but I believe it is better than was
before.
Reviewed By: artempyanykh
Differential Revision: D17600175
fbshipit-source-id: ca7175b2e
Summary:
Eradicate.ml is way too big to reason about.
This diff is shallow, it does only the following:
1. Moves the module
2. Adds documentation in the header.
3. Exports two public methods as is
4. Adds corresponding params to all methods for values that were
captured in the module-as-closure before
Reviewed By: artempyanykh
Differential Revision: D17600173
fbshipit-source-id: ba7981228
Summary:
Now, that we consistently use `AnnotatedType`, `AnnotatedNullability`,
and `AnnotatedSignature`, `AnnotatedField` is a natural name for this
datatype.
Together `AnnotatedSignature` and `AnnotatedField` represent two entry
points for fetching information about Java type from the codebase.
Reviewed By: artempyanykh
Differential Revision: D17570534
fbshipit-source-id: 31ef52033
Summary:
1. This diff finishes the work of getting rid of using `Annot.Item.t`
for making judgements about nullability. Instead, `AnnotatedNullability`
is now used consistently in the codebase. Corresponding TODO items are
deleted.
2. This diff proceeds consolidating checks to `NullsafeRules` (which
will simplify introducing non-binary nullability in follow up diffs).
3. Code is simplified: we get rid of `fold2/ignore` + inlined
calculation of the param position in favor of
more straightward `zip` + `iteri` combo.
Reviewed By: artempyanykh
Differential Revision: D17570439
fbshipit-source-id: 52acf2c66
Summary:
This continues work of getting rid of using low-level Annot.Item.t in
favor of a new, more specific and flexible data structure.
Migrating this code further to NullsafeRules is bit tricky right now, so
let's defer it.
Reviewed By: ngorogiannis
Differential Revision: D17549479
fbshipit-source-id: 418b4b394
Summary:
This diff also introduces "subtyping function" into NullsafeRule, which
will be the core check for other rules we will introduce in follow up
diffs
Reviewed By: ngorogiannis
Differential Revision: D17500466
fbshipit-source-id: 5821caa6e
Summary:
As suggested by artempyanykh:
1. Since we recently introduced InferredNullability, AnnotatedNullability deserves its own class which now plays nicely with its counterpart.
2. AnnotatedType is more specific then NullsafeType
Reviewed By: artempyanykh
Differential Revision: D17547988
fbshipit-source-id: 785def23a
Summary:
This proceed the work of getting rid of Annot.Item.t.
This diff:
- Moves "check assignment rule" to recently supported NullsafeRules
- Implements their own "check overannotated" (defers consolidating this
check into NullsafeRule for the future diffs).
Note that we don't need PropagatesNullable logic anymore because it is
already ported to NullsafeType (return value will be marked as Nullable
in NullsafeType)!
implicit_nullable (a.k.a. Void types) will require a follow up diff to
model.
Reviewed By: artempyanykh
Differential Revision: D17499246
fbshipit-source-id: 14b473f29
Summary:
In nutshell, Nullsafe is driven by relatively simple set of rules.
It is currently not well reflected in code: we are duplicating the same logic in different places, which is:
- error prone (we need to adjust ensure all places are addressed if a new feature is introduced)
- complicates understanding of nullsafe
Consolidating checks will simplify introducing Unknown Nullability and
strict/partial check modes.
## this diff
This diff does it for one particular check.
See follow up diffs re that proceed consolidation.
## future diffs
Future diffs will:
- consolidate other checks that use 'assignment rule'
- introduce other rules, most notably 'dereference rule' and
'inheritance rule'
Reviewed By: artempyanykh
Differential Revision: D17498630
fbshipit-source-id: 079d36518
Summary:
Now, after series of modifications with TypeAnnotation, we are ready to
rename it to reflect what it means in the code.
See the documentation in the class for details.
Also:
- renamed methods for clarity
- added some documentation
- renamed local variables around the usages
Reviewed By: jvillard
Differential Revision: D17480799
fbshipit-source-id: d4408887a
Summary:
This continues work for eliminating Annot.Item.t from Nullsafe low-level
code.
The introduced function `from_nullsafe_type` is called when we infer
initial type of the equation based on the function or field formal signature.
Before that, we did it via reading the annotation directly, which
complicates the logic and making introducing Unknown nullability tricky.
## Clarifying the semantics of PropagatesNullable
This diff also clarifies (and changes) the behavior of PropagatesNullable params.
Previously, if the return value of a function that has PropagatesNullable params was
annotated as Nullable, nullsafe was effectively ignoring PropagatesNullable effect.
This is especially bad because one can add Nullable annotation based on the logic "if the function can return `null`, it should be annotated with Nullable`.
In the new design, there is no possibility for such a misuse: the code that
applies the rule "any param is PropagatesNullable hence the return
value is nullable even if not explicitly annotated" lives in NullsafeType.ml, so
this will be automatically taken into account.
Meaning that now we implicitly deduce Nullable annotation for the return value, and providing it explicitly as an alternative that does not change the effect.
In the future, we might consider annotating the return value with `Nullable` explicit.
Reviewed By: jvillard
Differential Revision: D17479157
fbshipit-source-id: 66c2c8777
Summary:
As per previous diff, attempt to allocate fewer strings. This doesn't
seem to affect perf although allocating less might reduce memory
pressure.
Reviewed By: mityal
Differential Revision: D17423973
fbshipit-source-id: e2e37b071
Summary:
1/ Nikos Gorogiannis pointed out that
- for highly reused public types, records (especially when >= 3 params) are generally more readable than tuples.
- Records simplify code modifications, especially adding new fields. And we are going to add some, namely param flags, in the future.
2/ Let's make the fact that annotated signature is deprecated more
visible; it will also simplify searching for usages when we will be
getting rid of them.
Reviewed By: ngorogiannis
Differential Revision: D17475033
fbshipit-source-id: 7740c979b
Summary:
`get_field_annotation` is (together with
`get_modelled_annotated_signature`) an entry point when Nullsafe fetches
annotation information.
In follow up diffs we are going to utilize added information; see also
TODO in the code
Reviewed By: ngorogiannis
Differential Revision: D17475034
fbshipit-source-id: dab77bc7b
Summary:
"Unannotated" is misleading and ambiguous concept, it can have different
meanings depending on agreements.
The current logic treats them as Nonnull, which is exactly what we want
to preserve.
(If we need to partially model some functions where we don't have
opinion on some of types in the signature, we can explicitly model
unknown nullability later on).
Note that I am not aiming for substantial refactoring of
modelsTables.ml; the scope of this diff is merely to clarify things.
Reviewed By: ngorogiannis
Differential Revision: D17449347
fbshipit-source-id: 43c798ce7
Summary:
This function is the main entry point for getting annotated signature
for nullsafe.
We will modify it and its callees in follow up diffs to migrate other
features of Annot.items to specialized types.
Reviewed By: ngorogiannis
Differential Revision: D17448082
fbshipit-source-id: be00b4737
Summary:
This is a central abstraction for coming future unknown nullability support.
# Context
Annot.ml is a low-level module:
- it contains lists of raw (string) annotations
- no algebraic datatypes for annotations
- it mixes annotations that Nullsafe should be aware of with all sorts of other annotations
- some annotations make sense for return values, some make sense for params, and some make sense for methods.
But, most importantly, it does not contain information about source of an annotation, making it hard to distinct things like "Nonnull as default" vs "Nonnull as explicitly annotated" vs "Nonnull as modelled". Ditto for nullable.
Because of this, it is tricky to introduce unknown nullability in an elegant way.
Let's get rid of using Annot.Item.t in nullsafe code in the following way:
- Move nullability information associated with the Java type to a dedicated algebraic DT.
- Split other annotations that are important for nullsafe into param flags, ret value flags, and method flags, and introduce corresponding datatypes.
# This diff
This diff introduces NullsafeType and adds this to AnnotatedSignature.
It is not used yet, hence the diff is a no-op.
In future diffs, we are going to (see also TODOs in the code):
- actually use this information instead of accessing Annot.item
- add more information to AnnotatedSignature
- remove Annot.item from AnnnotatedSignature
- when this is done, introduce notion of unknown nullability.
Reviewed By: ngorogiannis
Differential Revision: D17420595
fbshipit-source-id: b30706d9b
Summary:
We historically had Model.Inference, which was an attempt to enhance
models with additional abilities to get the annotation.
This feature got removed in D9805110, including removing of the key
condition Models.Inference.field_is_marked.
This code also is not executed: `Config.eradicate` condition
was an old artefact of migrating Eradicate to callback infrastructure:
D1508451. We run eradicate only as a callback as of now, so this flag is
always true.
In follow up diffs we refactor AnnotationSignature module, and this
cleanup simplifies the refactoring.
Reviewed By: ngorogiannis
Differential Revision: D17419173
fbshipit-source-id: 1b30555de
Summary:
CONDITION_REDUNDANT_NONNULL was an attempt to reduce number of false
positives for condition redundant. (It is the most popular check as of
now).
The root case for most of false positives is that a lot of code is
simply not annotated (but should have been), so blaming developers for defense programming is
not actionable.
In attempt to solve the problem, a special issue type (for case when the
code is explicitly annotated with Nonnull) was introduced.
In follow up diffs we are going to introduce a generic way of doing the
same, not limited to this particular check only.
Namely, we will introduce notion of unknown nullability, so it will be
possible to distinguish not annotated yet (hence no warnings) and already
annotated (hence warnings) parts of code.
This piece of logic is incompatible with the aforementioned work, hence
we need to remove it.
Reviewed By: jvillard
Differential Revision: D17398768
fbshipit-source-id: 8bddf10e5
Summary:
At some point, there was a custom equality function that deliberately ignored some fields in err_instance. It was deleted in D4232422, so having a custom hash function does not serve any purpose anymore.
Since 2016 there was no known problems with the change in D4232422.
If we decide that we need similar behavior that was before D4232422, it will be easier to reimplement the functionality again.
Reviewed By: jberdine
Differential Revision: D17313660
fbshipit-source-id: 5c6c29a0b
Summary:
This check was an incomplete attempt to make nullsafe check nutritious
annotations for fields that get modified.
This was never fully productionized, and this check is turned off by
default.
In near future, we don't anticipate supporting this feature, so let's
remove it to simplify the code.
Reviewed By: artempyanykh
Differential Revision: D17282015
fbshipit-source-id: d63a2f1f7
Summary:
There are currently plenty of ways to suppress the warning, including Inject, Initializer, and SuppressFieldNotInitialized annotations.
This one (annotating field with Nonnull) is counter-intuitive and does not align with gradual nullsafe
semantics we are working on.
Reviewed By: artempyanykh
Differential Revision: D17281702
fbshipit-source-id: 132e1b687
Summary:
This diff makes the checkers, except biabduction, to use `typ` instead
of `root_typ` of `Load`/`Store` statemetns.
Reviewed By: dulmarod
Differential Revision: D17203105
fbshipit-source-id: 8be9b5158
Summary:
It uses inline record for Sil.Load and Sil.Store for preparing the
following extention.
Reviewed By: dulmarod
Differential Revision: D17161288
fbshipit-source-id: 637ea7bfa
Summary:
This abstraction was not always used consistently.
Its usage made more sense when it supported both present annotations and
optional annotation (which got removed in previous diff).
The rought semantic of that was "what is the inferred type for such and
such value (variable or expression) in typestate". So it is not really
_annotation_ in first place, it is more like "what we inferred about
nullability given annotations, known special cases, and current sybmolic
execition state".
Let's explicitly rename `map` to `is_nullable`. If/when we need to
enhance this further (and we likely will), we will do it accordingly.
Reviewed By: jvillard
Differential Revision: D17153434
fbshipit-source-id: 3c85b56df
Summary:
`Present` annotation was an experiment made many years ago that never
got into real usage. The idea was to annotate Optional<> types with
Present, which means that it is safe to call get().
We don't plan to support `Present` annotation for optional types in the
near future.
Support of `Present` annotation requires extra levels of abstraction
that make the changing the behavior and introducing new features harder.
A lot of checks for nullability are written in generic way so they also
check for presense.
Getting rid of that will allow us to simplify our
work for introducing new semantics for nullsafe.
Reviewed By: ngorogiannis
Differential Revision: D17153432
fbshipit-source-id: c5ea9bdf1
Summary:
`nullsafe` currently allows the following:
```
public void Nonnull Object willBeOK() { return null; }
```
But disallows the following:
```
public void Object willBeAnIssue() { return null; }
```
This was a deliberate choice made back in 2014.
The motivation was to provide a way to tell the checker "I know it can not be null, trust me".
A huge problem with that approach is that it is extremely non-intuitive and surprising, and contradicts with pretty much everything when Nonnull or similar annotations are used in external world.
This is not the way how checkers should be supressed.
We do provide 2 options to express this intention, namely `assertNotNull` and `assumeNotNull` would do the thing.
This is a much better approach for additional reason: assertNotNull is
granular and applies only to the exact expression that is under
question. In contrast, suppressing the check on the whole function level
make any modifications of a function dangerous.
Reviewed By: artempyanykh
Differential Revision: D16984213
fbshipit-source-id: 0ba0f623b
Summary:
Summary.ml defines both a bunch of types and how to use them and a
mechanism to save and store summaries on disk while maintaining a
complex in-memory cache of what's on disk. Make the distinction clear.
Reviewed By: ngorogiannis
Differential Revision: D16358869
fbshipit-source-id: 9d4c6cb77
Summary:
Fixes#1126
Different checks contain some ad hoc places that look at this param, but there is no systematic way to suppress this.
The centralized place that is filtering results is `reporting.ml`.
Note that this diff does not remove other usages, because they do more than mere filtering results.
Reviewed By: jvillard
Differential Revision: D16339655
fbshipit-source-id: afabdc97a
Summary:
The fields `tenv` and `integer_type_widths` can be obtained from the `exe_env` field of `proc_callback_args`
This commit removes the redundant fields
Reviewed By: ngorogiannis
Differential Revision: D16149520
fbshipit-source-id: d37526fd4
Summary:
Change the datatype `ProcData` to include a field of type `Summary.t` instead of a field of type `Procdesc.t`
This will enable a later commit to supply a summary to `Ondemand.analyze_proc_desc` and `Ondemand.analyze_proc_name`
Reviewed By: ngorogiannis
Differential Revision: D16121405
fbshipit-source-id: 342374121
Summary:
The record `proc_callback_args` (defined in `callbacks.ml`) contains the fields `proc_desc` and `summary`.
The field `proc_desc` is redundant because it can be obtained from `summary`.
This diff removes `proc_desc` and uses the summary to obtain it where needed.
Reviewed By: ngorogiannis
Differential Revision: D16090783
fbshipit-source-id: 5632d1f4a
Mitya Lyubarskiy
Nikos Gorogiannis
Josh Berdine
Artem Pianykh
Jules Villard
Sungkeun Cho
Phoebe Nichols