Summary:
We model Enum.name as returing a constant name, rather than getting real field names. We did this
because we couldn't think of any big gains, in terms of analysis precision/performance, from getting
the real names.
Reviewed By: ezgicicek
Differential Revision: D21201730
fbshipit-source-id: a2dc01a44
Summary: This diff revises the models of Collection.set and get to handle its elements.
Reviewed By: ezgicicek
Differential Revision: D21201242
fbshipit-source-id: 9c248453d
Summary: Java has this pattern of wrapping non-thread-safe containers in factory methods producing identically-typed results, but wrapped in a synchronised shell. This diff teaches RacerD about some common factory methods and uses the attribute domain to track the dynamic type of their results.
Reviewed By: ezgicicek
Differential Revision: D21155538
fbshipit-source-id: 42ebe6251
Summary: Complete the set of models for java containers that Infer should not report thread safety violations.
Reviewed By: ezgicicek
Differential Revision: D21138280
fbshipit-source-id: 01e1944b6
Summary: Models were partial and/or simply missing (`Map` writes!). Now the modelled containers use inheritance for conciseness (`List` reads are only those not caught by the `Collection` matcher, etc). Also, add URLs to documentation sources.
Reviewed By: ezgicicek
Differential Revision: D21132069
fbshipit-source-id: fefb360f0
Summary: This diff suppresses cost issues on lambda and auto-generated procedures, since they were too noisy.
Reviewed By: ezgicicek
Differential Revision: D21153619
fbshipit-source-id: 65ad6dcc3
Summary:
Replace horrible hack with ok hack.
The main difficulty in implementing the disjunctive domain is to avoid
the quadratic time complexity of executing the same disjuncts over and
over again when going around loops:
First time around a loop, assuming for example a single disjunct `d`:
```
[d]
loop body
[d1' \/ d2']
```
Second time around the same loop: the new pre will be the join of the
posts of predecessor nodes, so `old_pre \/ post(loop,old_pre)`, i.e.
`d \/ d1' \/ d2'`. Now we need to execute `loop body` again
*without running the symbolic execution of `d` again* (and the time after
that we'll want to not execute `d`, `d1'`, or `d2'`).
Horrible hack (before): Disjuncts have a boolean "visited" attached
that does its best to keep track of whether a given disjunct is old or
new. When executing a single *instruction* look at the flag and skip the
state if it's old. Of course we have no way to know for sure so it turns
out it was often wrongly re-executing old disjuncts. This was also
producing the wrong results over even simple loops: only the last
iteration would make it outside the loop for some reason. Overall, the
semantics were pretty untractable and shady at best.
New hack (this diff): only run instructions of a given *node* on
disjuncts that are not physically equal to the "pre" ones already in the
invariant map for the current node.
This gives the correct result over simple loops and a nice performance
improvement in general (probably the old heuristic was hitting the
quadratic bad case more often).
Reviewed By: skcho
Differential Revision: D21154063
fbshipit-source-id: 5ee38c68c
Summary:
1. Package will make the error too verbose.
2. We don't even need to say it is "class" because we say it in the error
description ("Class has 0 issues and can be marked Nullsafe").
Reviewed By: artempyanykh
Differential Revision: D21131998
fbshipit-source-id: 6ccca7615
Summary:
One source of false positives on container races is when the container member field is initialised to a concurrent version in a constructor, but the static type of the field doesn't reflect the thread safety of it.
This solution
- tracks flows from constructors of safe data structures to abstract addresses;
- initialises the initial attribute state when analysing a non-constructor method to that achieved by all constructors/class-initializers.
- checks for that attribute when recording container accesses.
Reviewed By: jvillard
Differential Revision: D21089428
fbshipit-source-id: 02a88f6e8
Summary:
There are two types of anonymous classes (not user defined classes):
- classic anonymous classes (defined as $<int> suffixes)
- lambda classes (corresponding to lambda expressions). Experimentally,
they all have form `$Lambda$_<int>_<int>`, but the code just uses
`$Lambda$` as a heuristic so it is potentially more robust.
# Problem this diff solves
When generate meta-issues for nullsafe, we are interested only in
user-defined classes, so we merge all nested anonymous stuff to
corresponding user-defined classes and hence aggregate the issues.
Without this diff, for each lambda in the code, we would report this as
a separate meta-issue, which would both screw up stats and be confusing
for the user (when we start reporting mode promo suggestions!).
Reviewed By: artempyanykh
Differential Revision: D21042928
fbshipit-source-id: a7be266af
Summary:
This diff revises how to handle the unknown location in inferbo in two ways:
* stop appending field to the `Unknown` location, e.g. `Unknown.x.a` is evaluated to `Unknown`
* redesign the abstract of multiple locations, like `Bottom` < `Unknown` < `Known` locations
I am doing them in one diff since applying only one of them showed bad results.
Background: `Unknown` was adopted for abstracting all unknown concrete locations, so we could avoid missing semantics of assignments to unknown locations. We tried to keep soundness. However, it brought some other problems related to precision and performance.
1. Sometimes especially when Inferbo failed to reason precise pointer values, `Unknown` may point to many other abstract locations.
2. At that time, value assignments to `*Unknown` makes the situation worse: many abstract locations are updated with imprecise values.
This problem harmed not only its precision, but also its performance since it introduced more location entries in the abstract memory.
Reviewed By: jvillard
Differential Revision: D21017789
fbshipit-source-id: 0bb6bd8b5
Summary:
See the code comment re: why don't we also recommend "strict" at this
stage. We can always change it later when we think users are happy with
strict.
Reviewed By: artempyanykh
Differential Revision: D21039553
fbshipit-source-id: 758ccf32c
Summary:
This diff is a step forward to the state when the list of type violations is
independent of the mode (and we use mode solely to decide re: whether to
report or not).
This fixes a case when we incorrectly defined possible promo mode (see
the test payload)
Reviewed By: artempyanykh
Differential Revision: D20948897
fbshipit-source-id: 616b96f96
Summary:
See the comments in the code why it makes logical sense.
This diff is a step forward the state when list of type violations is
independent of the mode (and we use mode solely to decide re: whether to
report or not).
This fixes majority of cases in ModePromotions.java
Reviewed By: artempyanykh
Differential Revision: D20948656
fbshipit-source-id: 82c0d530b
Summary:
Currently we exlude only if the method is based on deprecated config
packages.
Lets use the proper method, which covers both cases (config +
user-defined third party repo).
Reviewed By: artempyanykh
Differential Revision: D20946506
fbshipit-source-id: c3332667f
Summary:
Previously, we learned to detect if Default mode class can be made
Nullsafe(LOCAL).
Lets generalize it and calculate the precise mode.
NOTE 1: We don't distinct shades of "Trust some". We also don't
recommend trust some and recommend "Trust all" instead.
NOTE 2: As you can see from the test payload (see ModePromotions.java),
the precise calculation is not working as expected. This is due to a bug
in nullsafe implementation/design. See follow up diffs that will fix
this test.
Reviewed By: artempyanykh
Differential Revision: D20941345
fbshipit-source-id: 2255359ba
Summary: Consider functions that simply exit as impure by extending the impurity domain with `AbstractDomain.BooleanOr` that signifies whether the program exited.
Reviewed By: skcho
Differential Revision: D20941628
fbshipit-source-id: 19bc90e66
Summary:
This information can be useful for tooling responsible for further
processing (e.g. metric calculation and logging)
Reviewed By: artempyanykh
Differential Revision: D20914583
fbshipit-source-id: 61804d88f
Summary: The heuristics is to find a method in non-abstract sub-classes. See D20647101.
Reviewed By: jvillard
Differential Revision: D20491461
fbshipit-source-id: 759713ef4
Summary:
This diff distinguishes array declaration and size-setting in trace. For example, when there is an
assume statement on an array size, the array size can be pruned to another value. In which case, we
want to see "Set array size" in the trace, instead of "Array declaration".
Reviewed By: jvillard
Differential Revision: D20914930
fbshipit-source-id: 0253fb69e
Summary:
This diff lifts the `PulseAbductiveDomain.t` in `PulseExecutionState` by tracking whether the program continues the analysis normally or exits unusually (e.g. by calling `exit` or `throw`):
```
type exec_state =
| ContinueProgram of PulseAbductiveDomain.t (** represents the state at the program point *)
| ExitProgram of PulseAbductiveDomain.t
(** represents the state originating at exit/divergence. *)
```
Now, Pulse's actual domain is tracked by `PulseExecutionState` and as soon as we try to analyze an instruction at `ExitProgram`, we simply return its state.
The aim is to recover the state at the time of the exit, rather than simply ignoring them (i.e. returning empty disjuncts). This allows us to get rid of some FNs that we were not able to detect before. Moreover, it also allows the impurity analysis to be more precise since we will know how the state changed up to exit.
TODO:
- Impurity analysis needs to be improved to consider functions that simply exit as impure.
- The next goal is to handle error state similarly so that when pulse finds an error, we recover the state at the error location (and potentially continue to analyze?).
Disclaimer: currently, we handle throw statements like exit (as was the case before). However, this is not correct. Ideally, control flow from throw nodes follows catch nodes rather than exiting the program entirely.
Reviewed By: jvillard
Differential Revision: D20791747
fbshipit-source-id: df9e5445a
Summary:
Currenlty the cost issue is printed at the first node of a function, which is usually the first
statment of the function. This may give a wrong impression that the cost of the statement is
changed.
This diff re-locate where to print issues with heuristics. Going backward from the first node
lines, it looks up a line satisfying,
1. A line should start with <fname> or should include " <fname>".
2. The <fname> found in 1 should be followed by a space, '<', '(', or end of line.
Reviewed By: jvillard
Differential Revision: D20766876
fbshipit-source-id: b4fee3180
Summary:
To find a method in non-abstract sub-classes, this diff applies the
same heuristics of inferbo.
* If the class is an interface: Find its unique sub-class and apply the heuristics recursively.
* If the class is an abstract class: Find/use its own summary if possible. If not found, find
one (arbitrary but deterministic) summary from its sub-classes.
* Otherwise: Find its own summary.
Reviewed By: ezgicicek
Differential Revision: D20647101
fbshipit-source-id: 2f8f3ff81
Summary:
Morally, INTERFACE_NOT_THREAD_SAFE is issued when an interface method is invoked from `ThreadSafe`-annotated code on an interface that is not known to be thread-safe or annotated so.
However, the ultimate purpose is to prevent races. Thus it should never be issued on an owned object or on objects we would not report races on for any reason (local variables, non-source variables, etc).
This diff equips interface call records with the abstract address they are invoked on, and uses the same rules for maintaining those records or not.
Reviewed By: skcho
Differential Revision: D20669259
fbshipit-source-id: 6c7841e6a
Summary:
- Model `System.exit()` as early_exit and add a test
- Tweak message of methods that are impure due to having no pulse summary (and add a test)
Reviewed By: skcho
Differential Revision: D20668979
fbshipit-source-id: 6b5589aae
Summary: This diff avoids that an invalid interval value, e.g. [0, -1], is genrated by interval pruning.
Reviewed By: ezgicicek
Differential Revision: D20645488
fbshipit-source-id: 6516c75d1
Summary: The current message is recommending to change `View.findViewById()` to `View.requireViewById()`, but the latter method is not supported in all API, so might lead to a crash in runtime.
Differential Revision: D20619361
fbshipit-source-id: 542746c79
Summary:
- the order of call state was wrong when printing contradiction for CItv
- add a test for impurity
Reviewed By: jvillard
Differential Revision: D20646181
fbshipit-source-id: 1c86fd0a4
Summary:
As exemplified by added tests, pulse computes an empty summary (with 0 disjuncts) whenever it discovers a contradiction which might be caused by:
- discovering aliasing in memory
- widening limited number of times in loops and concluding that loop exit conditions are never taken
However, AFAIU, it is not possible to have a function with 0 disjunct apart from such anomalities. Even a function which does nothing like `void foo(){}` has 1 disjuncts:
```
Pulse: 1 pre/post(s)
#0: PRE:
{ roots={ };
mem ={ };
attrs={ };}
POST:
{ roots={ };
mem ={ };
attrs={ };}
SKIPPED_CALLS: { }
```
The aim of this diff is to consider functions with 0 disjuncts as **impure** because most often such cases are impure, rather than actually pure.
Reviewed By: skcho
Differential Revision: D20619504
fbshipit-source-id: 3a8502c90
Summary:
Although try-with-resource is supported by nullsafe this code pattern
throws it off and make nullsafe report on a virtual **b**yte-**c**ode
variable.
Check out debug output from `TryWithResource` (or attached
visualisation of CFG):
0. node14: $bcvar2=null (on entry to try-with-resource).
1. node16: n$14=$bcvar2, but **also** PRUNE(!(n$14 == null), true). Then we go to
2. node18: do something here and in case of exception go to
3. node25->node23->node19->node20: and here we do
$bcvar2->addSuppressed(...).
Because on step 1 we refined nullability of n$14, but didn't refine
nullability of $bcvar20, on step 3 we are sure that $bcvar is null and
therefore issue an error.
Reviewed By: mityal
Differential Revision: D20558343
fbshipit-source-id: 520505039
Summary:
This is likely not the final refinement, rather one step forward.
We classify all classes by 3 categories:
- Nullsafe and 0 issues
- can add Nullsafe and will be 0 issues
- the rest (class needs improvement)
Each class will fall into exactly one category.
Error messaging is WIP, they are not intended to be surfaced to the user
just yet.
Note how this diff uses the result of the previous refactoring.
Reviewed By: artempyanykh
Differential Revision: D20512999
fbshipit-source-id: 7f462d29d
Summary: Add a flag `is-inclusive-cost` (`true` by default) which computes inclusive cost for each function. Setting the flag to `false` computes exclusive cost of the function where the cost of the callees are assumed to be `0`.
Reviewed By: skcho
Differential Revision: D20558275
fbshipit-source-id: 6b5798916
Summary:
# Problem
Consider
```
some_method(Object a) { a.deref(); }
```
What is nullability of `a` when we dereference it?
Logically, things like "LocallyCheckedNonnull" etc are not applicable
here.
This would be applicable if we called some_method() outside! But not
inside. Inside the function, it can freely treat params as non-null, as
long they are declared as non-nullable.
The best we can capture it is via StrictNonnull nullability.
Reviewed By: artempyanykh
Differential Revision: D20536586
fbshipit-source-id: 5c2ba7f0d
Summary:
`make test` failed in some test directories, because we were getting warnings
```
Foo.java uses unchecked or unsafe operations.
```
This diff fixes or suppresses these warnings.
Reviewed By: skcho
Differential Revision: D20557572
fbshipit-source-id: 63ecd3dfa
Summary:
- Add more naive pulse models for:
- `System.arraycopy`
- `StringBuilder.setLength`
- `StringBuilder.delete`
- Model the following as pure
- `SparseArrayCompat.valueAt`
- `File.get...`
- Add a nice test
Reviewed By: jvillard
Differential Revision: D20513397
fbshipit-source-id: 6d412d13a
Summary:
This diff continues work in D20491716.
This time for Inheritance Rule.
Reviewed By: jvillard
Differential Revision: D20492889
fbshipit-source-id: c4dfd95c3
Summary:
This diff continues work in D20491716.
This time for Dereference Rule.
Reviewed By: jvillard
Differential Revision: D20492296
fbshipit-source-id: ff7f824f9
Summary:
# Problem
In current design, Rules (assignment rule, dereference rule, inheritance
rule) decide, depending on the mode, wether the issue is legit or not.
If the issue is not actionable for the given mode, it won't be created
and registered.
For meta-issues, we want to be able to do smart things like:
- Identify if we can raise strictness of the mode without
introducing new issues
- Classify classes on "clean" vs "broken", taking into account issues
that are currently invisible.
# Solution
In the new design:
1. Rules are issuing violations independently of mode. This makes sense
semantically. Mode is "level of trust we have for suspicious things",
but the thing does not cease to be suspicious in any mode.
2. Each Rule decides if it is reportable or not in a given mode.
3. `nullsafe_mode` is passed to the function `register_error`, that 1)
adds error so it can be recorded in summary for file-level analysis
phase 2) reports some of them to the user.
# This diff
This diff converts only AssignmentRule, follow up will include
conversion of other rules, so no issue encapsutes the mode.
Reviewed By: jvillard
Differential Revision: D20491716
fbshipit-source-id: af17dd66d
Summary:
Previously, at each function call, we added a `WrittenTo` attribute for applying the address of the actuals. However, this results in mistakenly considering each function application that inspects its argument as impure. Instead, we should only propagate `WrittenTo` if the actuals have already `WrittenTo` attributes.
For instance, for the following functions
```
public static boolean is_null(Byte a) {
return a == null;
}
public static boolean call_is_null(Byte a) {
return is_null(a);
}
```
We used to get the following pulse summary for `call_is_null` (showing only one of the disjuncts):
```
#0: PRE:
{ roots={ &a=v1 };
mem ={ v1 -> { * -> v2 } };
attrs={ v1 -> { MustBeValid },
v2 -> { Arith =null, BoItv ([max(0, v2), min(0, v2)]) } };}
POST:
{ roots={ &a=v1, &return=v8 };
mem ={ v1 -> { * -> v2 }, v8 -> { * -> v4 } };
attrs={ v2 -> { Arith =null,
BoItv ([max(0, v2), min(0, v2)]),
WrittenTo-----------WRONG },
v4 -> { Arith =1,
BoItv (1),
Invalid ConstantDereference(is the constant 1),
WrittenTo-----------WRONG },
v8 -> { WrittenTo } };}
SKIPPED_CALLS: { }
```
where we mistakenly recorded a `WrittenTo` for `v2` (what `a` points to). As a result, we considered `call_is_null` as impure :( This diff fixes that since the callee `is_null` doesn't have any `WrittenTo` attributes for its parameter `a`. So, we don't propagate `WrittenTo` and get the following summary
```
#0: PRE:
{ roots={ &a=v1 };
mem ={ v1 -> { * -> v2 } };
attrs={ v1 -> { MustBeValid },
v2 -> { Arith =null, BoItv ([max(0, v2), min(0, v2)]) } };}
POST:
{ roots={ &a=v1, &return=v8 };
mem ={ v1 -> { * -> v2 }, v8 -> { * -> v4 } };
attrs={ v2 -> { Arith =null, BoItv ([max(0, v2), min(0, v2)]) },
v4 -> { Arith =1,
BoItv (1),
Invalid ConstantDereference(is the constant 1) },
v8 -> { WrittenTo } };}
SKIPPED_CALLS: { }
```
Reviewed By: skcho
Differential Revision: D20490102
fbshipit-source-id: 253d8ef64
Summary: These tests fail when seemingly unrelated changes are made to infer. In particular, it seems timeout limits have to be increased by 10x or more to make them succeed again. Disabling until we have a more stable replacement.
Reviewed By: ezgicicek
Differential Revision: D20489647
fbshipit-source-id: 9706b0807
Summary:
This diff naively models the following as `StdVector.push_back`:
- `StringBuilder.append`
- `String.replace`
- `Queue.poll`
It also adds a FN test for `Iterator.next`.
Reviewed By: skcho
Differential Revision: D20469786
fbshipit-source-id: 2d8e8d117
Summary:
This diff is doing three things:
1. Finishes work paved in D20115024, and applies it to nullsafe. In that diff, we hardened API for
file level analysis. Here we use this API in nullsafe, so now we can
analyze things on file-level, not only in proc-level like it was before!
2. Introduces a class-level analysis. For Nullsafe purposes, file is not
an interesting granularity, but we want to analyze a lot of things on
file level. Interesting part here is anonymous classes and how we link
them to their corresponding user-defined classes.
3. Introduces a first (yet to be improved) implementation of class-level
analysis. Namely it is "meta-issues" that tell what is going with class
on high level. For now these are two primitive issues, and we will
refine them in follow up diffs. They are disabled by default.
Follow ups include:
1. Refining semantics of meta-issues.
2. Adding other issues that we could not analyze before or analyzed not
user friendly. Most importantly, we will use it to improve reporting for
FIELD NOT INITIALIZED, which is not very user friendly exactly because
of lack of class-level aggregation.
Reviewed By: artempyanykh
Differential Revision: D20417841
fbshipit-source-id: 59ba7d2e3
Summary: The `FN_loop2` was not actually FN because infer analyzes its complexity as degree 1 correctly.
Reviewed By: dulmarod
Differential Revision: D20468367
fbshipit-source-id: 9e4c19415
Summary: The `iterate_over_mycollection_quad_FN` was not actually FN because infer analyzes its complexity as degree 2 correctly. So, this diff removed `_FN` from there.
Reviewed By: ezgicicek
Differential Revision: D20467398
fbshipit-source-id: b10340612
Summary: There has never been a sufficient formal basis for soundness nor completeness of reports on locals. This diff changes the domain to effectively concern only expressions rooted at formals or globals.
Reviewed By: ezgicicek
Differential Revision: D19769201
fbshipit-source-id: 36ae04d8c
Summary: `Object.clone` modeled as pure until the analysis can distinguish returning a fresh object vs. having no side-effects.
Reviewed By: skcho
Differential Revision: D20439998
fbshipit-source-id: 421054cfb
Summary:
`JavaSplitName` is used to represent Java types (in `Procname` in particular). The type itself is a pair of string (an optional package qualifier) and a "type name" (the quotes are there because it may contain array qualifiers).
For example `java.lang.Object[][]` should be represented as
```
{package=Some "java.lang"; typename="Object[][]"}
```
The constructor `make` was misused to construct instead types such as
```
{package=None; typename="java.lang.Object[][]"}`
```
This is evident when we print the return type of a `Procname` non-verbosely (the default), but we still see the package qualifier.
Obviously this is not just a pretty-printing bug, the values were themselves wrong.
The fix is to use the `of_string` constructor which will parse the package and separate it correctly. Another bug (in response to this one) had to be fixed in `Procname.is_vararg` to maintain behaviour in Nullsafe and Quandary.
Reviewed By: mityal
Differential Revision: D20394146
fbshipit-source-id: 4633902eb
Summary:
Impurity domain was tracking all changes to variables (with a list of traces that containing all write/invalid accesses). This results in having long traces with multiple access events for the same variable. For instance,
```
void swap_impure(int[] array, int i, int j) {
int tmp = array[i];
array[i] = array[j]; \\ included in the trace
array[j] = tmp; \\ included in the trace
}
```
here we recorded both array accesses.
This diff changes the domain to include accesses so that we only keep track of a single trace per access. Array accesses are only recorded once.
Note that we want to record all unique accesses, not just the first one, because impurity will be used for hoisting/cost where we will invalidate impure arguments and consider all the rest as not changing.
Reviewed By: jvillard
Differential Revision: D20385745
fbshipit-source-id: d3647dad3
Summary:
D20362149 missed
- to pass the optional argument `include_value_history` to the recursive call in `PulseTrace.add_to_errlog`.
- to set `include_value_history=false` for skipped calls.
This diff fixes these issues.
Reviewed By: skcho
Differential Revision: D20385604
fbshipit-source-id: 176e4d010
Summary:
Make <infer-out>/report.json the default value for this option, as this
is what is used 99% of the time. Clean up test options using this.
Reviewed By: ngorogiannis
Differential Revision: D20362644
fbshipit-source-id: a1bb18757
Summary: Impurity traces are quite big due to recording values histories. Let's simplify the traces by removing pulse's value histories.
Reviewed By: skcho
Differential Revision: D20362149
fbshipit-source-id: 8a2a6115e
Summary: Type is not enough to say a function call of `Provider.get` is expensive or not.
Reviewed By: jvillard
Differential Revision: D20366206
fbshipit-source-id: 83d3e8741
Summary:
This diff uses a type parameter of `Provider.get` to decide whether assigning expensive cost to the
function call or not. For example, if the type is small one like `Provider<Integer>`, it be
evaluated to have a unit cost, otherwise a linear cost.
To get the return type of `Provider.get`, I added a simple analyzer that collects "casted" types
backwards. In Sil, while the function call statement loses the return type, e.g,
```
n$5=_fun_Object Provider.get()(n$3:javax.inject.Provider*);
```
the `n$5`'s value is usually casted to a specific type at some point later.
```
*&$irvar0:java.lang.Object*=n$5
n$8=*&$irvar0:java.lang.Object*
n$9=_fun___cast(n$8:java.lang.Object*,sizeof(t=java.lang.Integer;sub_t=( sub )(cast)):void)
```
So, the analyzer starts from the cast statements backward, collecting the types to cast for each
variables.
Reviewed By: ezgicicek
Differential Revision: D20345268
fbshipit-source-id: 704b42ec1
Summary: This diff adds a model for Java's `Object.clone()` method (similar to existing shallow_copy).
Reviewed By: jvillard
Differential Revision: D20341073
fbshipit-source-id: 30ae40fe7
Summary:
Some (all?) of this is already tested in other tests, but this feature
is important enough (and the implementation is scattered accross the
whole code), so I found it useful to have a small test that ensures the
very basic things are working as expected.
See `NestedFieldAccess.java` that tests far more advances things, but
here we focus only very basic things: conditions, local variable
assignments, and explicit assignments.
Reviewed By: jvillard
Differential Revision: D20339056
fbshipit-source-id: a6cfd0043
Summary: We forgot to take skipped calls into account for state comparison. This diff fixes that.
Reviewed By: skcho
Differential Revision: D20282739
fbshipit-source-id: 7b4d84bb0
Summary:
These were not used (and were actually activated byt the same config
param). They both are in experimental stage that never reached maturity.
Since the team does not have immediate plans to work on ObjC nullability
checker; and since "eradicate" (now known as nullsafe) is the main
solution for Java, removing it is sensible.
Reviewed By: jvillard
Differential Revision: D20279866
fbshipit-source-id: 79e64992b
Summary:
This is the kind of property for which the previous syntax forced one to
use spurious registers.
Reviewed By: ngorogiannis
Differential Revision: D20118863
fbshipit-source-id: b49740d33
Summary:
This diff renames `ZERO_XXX` issues to more appropriately named and descriptive
`XXX_UNREACHABLE_AT_EXIT` and replaces bottom with
unreachable in cost kinds and issues.
Reviewed By: skcho
Differential Revision: D20140301
fbshipit-source-id: eb6076b30
Summary:
1. It is convenient to stick with the policy "ERROR if and only if it is
enforced". Among other, it makes CI integration much easier to implement
(enforcemend, UI and messaging is decided based on severity).
2. Since Nullsafe annotation is an idiomatic way to indicate classes
with enforced nullability checking, we want it to be the only way to
enforce issues.
3. This means we decrease the priority of GraphQL violation issues.
(In practice they were not enforced so we have plenty of violations in
codebase to reflect reality). The proper way dealing with GraphQL will
be detecting such issues as a special issue type and prioritizing fixing
and Nullsafe-ifying corresponding classes.
4. Among other, we downgrade severity of field overannotated to advice
to keep it consistent with condition redundant.
Reviewed By: artempyanykh
Differential Revision: D20141420
fbshipit-source-id: e2f12835a
Summary:
The issue type `ZERO_EXECUTION_TIME` actually corresponds to bottom state but has been mistakenly used to mean
- unreachable nodes (program never reaching exit state)
- having zero cost (e.g. for allocations).
Note that, for execution costs, the latter doesn't make sense since we always incur a unit cost for the start node. Hence, a function with empty body will have unit cost. For allocations or IO however, we only incur costs for specific primitives, so a function with no allocations/IO could have a zero cost. However, there is no point reporting functions with zero cost as a specific issue type. Instead, what we want to track is the former, i.e. functions whose cost becomes 0 due to program never reaching exit state.
This diff aims to split these cases into two by only reporting on the latter and adds traces to bottom/unreachable cost by creating a special category in polynomials.
Next diff will rename `ZERO_XXX` to `XXX_UNREACHABLE_AT_EXIT`.
Reviewed By: skcho
Differential Revision: D20005774
fbshipit-source-id: 46b9abd5a
Summary:
For Mode.Local this is kind of obvious decision.
But this diff does the same for strict mode as well.
See comment in [ExplicitNonnullThirdParty] for the detailed explanation.
Reviewed By: artempyanykh
Differential Revision: D20140056
fbshipit-source-id: 13c66df81
Summary:
In the previos diff we restructured error rendering utils for
TypeOrigin.MethodCall.
In this diff we do the same with TypeOrigin field: lets make the code
consistent.
We also clearly distinct third party from all other possible cases in
this branch.
This changes messaging and reported errors for strict modes (see test cases), and I believe this is a net improvement.
Reviewed By: artempyanykh
Differential Revision: D20139741
fbshipit-source-id: 84f502553
Summary:
> We don't report when the cost is Top as it corresponds to subsequent 'don't know's. Instead, we
> report Top cost only at the top level per function
The previous code just ignored top costed nodes, so it was able to report a non-top cost that was
from another node. For example,
```
void foo() {
linear-cost();
top-cost();
}
```
It reported inconsistent reports: `EXPENSIVE_EXECUTION_TIME` with a linear cost and
`INFINITE_EXECUTION_TIME` at the same time.
This diff fixes it not to report `EXPENSIVE_EXECUTION_TIME` when there is a node with the top cost.
Reviewed By: ezgicicek
Differential Revision: D20139408
fbshipit-source-id: 9fedd4aec
Summary:
In the previous report, it reported the first cost of node that exceeds a threshold. However, this
may hide a bigger cost of node that appears later. This diff changes this to report the biggest
cost of node among the costs exceeding the threshold.
Reviewed By: ezgicicek
Differential Revision: D20116162
fbshipit-source-id: 06199fb46
Summary:
This syntax
- is less confusing (according to several people who are not me);
objectively, there's less magic under the hood
- gives fine control over register number (because condition/action are separated)
- lets one compare values of different arguments of the same call
(e.g., one could have a transition that is taken only if two
arguments of a method call are equal)
Reviewed By: ngorogiannis
Differential Revision: D20005403
fbshipit-source-id: fad8f3b3d
Summary:
The test shows what that TOPL can express, in addition to bugs,
efficiency properties. However, there seems to be an underlying problem
in biabdaction that prevents this particular problem from being caught.
Reviewed By: ngorogiannis
Differential Revision: D20005404
fbshipit-source-id: 466f79050
Summary: The semantics of the `values` function of Java enum class was missing, when it is called outside the class initializer. This diff gets the size of the enum elements from the summary of class initializer function, `<clinit>`.
Reviewed By: ezgicicek
Differential Revision: D20094880
fbshipit-source-id: 7362bba1c
Summary:
Now when typechecking a class `A` marked with `Nullsafe(LOCAL)`,
classes from trusted list are properly recognized and nullability of
method params and return value are refined to `LocallyCheckedNonnull`
in a context of class `A`.
NOTE: refininng nullability when **accessing fields** on trusted classes
is **not implemented yet**, because the whole business of handling fields
in nullsafe is somewhat convoluted. This should not be a huge issue
though, since in Java fields are commonly accessed via getters any
way.
Reviewed By: mityal
Differential Revision: D20056158
fbshipit-source-id: 496433d90
Summary:
This will help making error reporting more actionable.
Often methods that are nullable in general (like View.findViewById) are used as not-nullable due to app-invariants. In such cases suggesting a non-nullable alternative that does an assertion under the hood makes the error report more actionable and provides necessary guidance with respect to coding best practices
Follow up will include adding more methods to models.
If this goes well, we might support it in user-defined area (nullability
repository)
Reviewed By: artempyanykh
Differential Revision: D20001416
fbshipit-source-id: 46f03467c
Summary:
Introduction of `ThirdPartyNonnull` nullability broke nullability
refinement heuristic for enums. This diff fixes it and also adds tests
so that we hopefully avoid such issues in future.
Reviewed By: mityal
Differential Revision: D19975810
fbshipit-source-id: f9245f305
Summary:
We need to be able to differentiate `UncheckedNonnull`s in internal vs
third-party code. Previously, those were under one `UncheckedNonnull`
nullability which led to hacks for optmistic third-party parameter
checks in `eradicateChecks.ml` and lack of third-party enforcement in
`Nullsafe(LOCAL, trust=all)` mode (i.e. we want to trust internal
unchecked code, but don't want to trust unvetted third-party).
Now such values are properly modelled and can be accounted for
regularly within rules.
Also, various whitelists are refactored using
`Nullability.is_considered_nonnull ~nullsafe_mode nullability`.
`ErrorRenderingUtils` became a tad more convoluted, but oh well, one
step at a time.
Reviewed By: mityal
Differential Revision: D19977086
fbshipit-source-id: 8337a47b9
Summary:
Add support for nullsafe mode with `trust=all` and `trust=none` a case
with a specific trust list is not supported yet and needs to be
implemented separately.
Tests introduce one unexpected
`ERADICATE_INCONSISTENT_SUBCLASS_PARAMETER_ANNOTATION` issue which
complains about `this` having incorrect nullability; it is a bug and
needs to be fixed separately.
Reviewed By: mityal
Differential Revision: D19662708
fbshipit-source-id: 3bc1e3952
Summary: In all other cases we have period at the end, which is inconsistent.
Reviewed By: artempyanykh
Differential Revision: D20001065
fbshipit-source-id: 85ec6d751
Summary:
Use a record of package, class name to store (qualified) Java class names. This saves the round trip of concatenating then splitting again, etc, as well as saves some memory in the type environment as now the package paths can be shared across classes of the same package (about 10% in tests).
Also remove some unfortunate APIs.
Reviewed By: jvillard
Differential Revision: D19969325
fbshipit-source-id: f7b7f5a55
Summary: The way `Mangled.t` is used in `JavaClassName` means that it's always a plain string (we never have a "mangled" part). Remove the indirection and extra allocation. Also, simplify the API by throwing away one function that was used just once and wastefully.
Reviewed By: artempyanykh
Differential Revision: D19950672
fbshipit-source-id: b61fcba6e
Summary:
This adds a violation of baos.topl found in github/seata/seata. However,
it is not a bug (see comment in commit).
Reviewed By: ngorogiannis
Differential Revision: D19518641
fbshipit-source-id: e219245ee
Summary:
Since Javalib 3.2, a new feature allows to rewrite
methods that contain (some specific form of) closures. Infer
now uses it. When loading each class we rewrite them and
new classes generated by Javalib to implements closures
(i.e. Java interfaces)<
Reviewed By: ngorogiannis
Differential Revision: D19389227
fbshipit-source-id: 245dd4404
Summary:
We already warn about lack of nullable annotations in `equals()`, and even have a specialized error message for that.
But lack of an annotation is not as severe as direct dereference: the
latter is a plain bug which is also a time bomb: it will lead to an NPE not immediately.
This is widespread enough to be reported separately.
Reviewed By: dulmarod
Differential Revision: D19719598
fbshipit-source-id: a535d43ea
Summary:
Since we fixed a bug in implementation of FalseOnNull (see stack below),
we can finally ship this change.
Side note: this change is essential for the follow up diff (which adds extra check
for user-defined implementations of equal()), without it the follow
up change would introduce a lot of false positives.
Reviewed By: ngorogiannis
Differential Revision: D19771057
fbshipit-source-id: 7d7cf1ef7
Summary:
If we managed to whitelist a function as TrueOnNull, we should teach
nullsafe the nullability of its arguments, otherwise it will ask not to
pass null here.
This fixes a silly FP warning, see the test.
Reviewed By: dulmarod
Differential Revision: D19770341
fbshipit-source-id: 0f861fae1
Summary:
Yay, the previous refactoring finally makes it possible to do some actual
changes to the code in `TypeCheck.ml`!
Changes in this diff:
1. Fixes the bug: TrueOnNull and FalseOnNull were working only for
static methods. Surpsingly nobody noticed that. It is because the first
argument for non-static method was `this`.
2. Behavior change: TrueOnNull/FalseOnNull were not working correctly
where there are several argumens. See the task attached for the example
of the legit usecase. Now the behavior is the following: if there are
several Nullable arguments infer nullability for all of them.
Reviewed By: skcho
Differential Revision: D19770219
fbshipit-source-id: 7dffe42cd
Summary:
This refactoring unblocks the changes in follow up diffs (plus fixes a
bug).
So what was happening?
Each comparison with null leads to CFG being splitted into two branches, one branch
is PRUNE(a == null) and another is PRUNE(a != null).
PRUNE(a != null) is where most of logic happens, it is the place where
we infer non-null nullability for a, and this is a natural place to
leave a check for redundancy.
Before this diff we effectively checked the same thing twice, and used
`true_branch` (only one of 2 instruction will have it set to true) as a symmetry breaker.
This diff removes the `true_branch` checks, but leaves only one call out
of two, hence breaking symmetry in a different way.
## Bug fix
The code around the removed check was (crazily) doing two things at
once: it processed results of (returning booleans!)
TrueOnNull-annotated functions AND
results of (returning Objects!) other functions, using the fact that all
of them are encoded as zero literals (sic!).
Not surprisingly that lead to a bug where we accidentally call the check
for non intended places (arguments of trueOnNull functions), which lead
to really weird FP.
This diff fixes it.
Reviewed By: dulmarod
Differential Revision: D19744604
fbshipit-source-id: fe4e65a8f
Summary: We don't use allocation costs in prod at the moment. There is no plan to do so in the near future. Let's not report them anymore and also save some space in `costs-report.json`.
Reviewed By: skcho
Differential Revision: D19766828
fbshipit-source-id: 06dffa61d
Sungkeun Cho
Nikos Gorogiannis
Jules Villard
Mitya Lyubarskiy
Daiva Naudziuniene
Ezgi Çiçek
Artem Pianykh
Radu Grigore
David Pichardie