Detect and fix situations when (force) unwrap is used on
a non-optional type, this helps to diagnose invalid unwraps
precisely and provide fix-its.
Resolves: [SR-8977](https://bugs.swift.org/browse/SR-8977)
Resolves: rdar://problem/45218255
This rule caused us to lose ambiguities in places where we really want ambiguity for `AnyObject` lookup, so only apply it when not comparing such overloads. This whole situation is a bit of a hack – really we shouldn't be applying any type-based or context-based overload ranking rules to overloads found through `AnyObject` lookup, but unfortunately we don't have syntax to precisely disambiguate overloads.
This commit can be reverted if/when we ever remove `AnyObject` lookup.
This builds on initial commit which added `RelabelArguments` fix
to the solver that only supported `missingLabels` at that moment,
but now it supports all three posibilities - missing/extraneous and
incorrect labels.
When we perform AnyObject lookup, we can find multiple declarations with
the same signature. When we do so, we pick fairly arbitrarily among them.
However, make sure that we don’t pick an unavailable declaration when
an available declaration is… available.
Fixes rdar://problem/39115471.
Stop creating ImplicitlyUnwrappedOptional<T> so that we can remove it
from the type system.
Enable the code that generates disjunctions for Optional<T> and
rewrites expressions based on the original declared type being 'T!'.
Most of the changes supporting this were previously merged to master,
but some things were difficult to merge to master without actually
removing IUOs from the type system:
- Dynamic member lookup and dynamic subscripting
- Changes to ensure the bridging peephole still works
Past commits have attempted to retain as much fidelity with how we
were printing things as possible. There are some cases where we still
are not printing things the same way:
- In diagnostics we will print '?' rather than '!'
- Some SourceKit and Code Completion output where we print a Type
rather than Decl.
Things like module printing via swift-ide-test attempt to print '!'
any place that we now have Optional types that were declared as IUOs.
There are some diagnostics regressions related to the fact that we can
no longer "look through" IUOs. For the same reason some output and
functionality changes in Code Completion. I have an idea of how we can
restore these, and have opened a bug to investigate doing so.
There are some small source compatibility breaks that result from
this change:
- Results of dynamic lookup that are themselves declared IUO can in
rare circumstances be inferred differently. This shows up in
test/ClangImporter/objc_parse.swift, where we have
var optStr = obj.nsstringProperty
Rather than inferring optStr to be 'String!?', we now infer this to
be 'String??', which is in line with the expectations of SE-0054.
The fact that we were only inferring the outermost IUO to be an
Optional in Swift 4 was a result of the incomplete implementation of
SE-0054 as opposed to a particular design. This should rarely cause
problems since in the common-case of actually using the property rather
than just assigning it to a value with inferred type, we will behave
the same way.
- Overloading functions with inout parameters strictly by a difference
in optionality (i.e. Optional<T> vs. ImplicitlyUnwrappedOptional<T>)
will result in an error rather than the diagnostic that was added
in Swift 4.1.
- Any place where '!' was being used where it wasn't supposed to be
allowed by SE-0054 will now treat the '!' as if it were '?'.
Swift 4.1 generates warnings for these saying that putting '!'
in that location is deprecated. These locations include for example
typealiases or any place where '!' is nested in another type like
`Int!?` or `[Int!]`.
This commit effectively means ImplicitlyUnwrappedOptional<T> is no
longer part of the type system, although I haven't actually removed
all of the code dealing with it yet.
ImplicitlyUnwrappedOptional<T> is is dead, long live implicitly
unwrapped Optional<T>!
Resolves rdar://problem/33272674.
We weren't previously testing every combination of dynamic with and
without IUO, so I've added tests to attempt to improve the situation.
We currently produce rvalues for dynamic lookups, which is incorrect,
and can be seen in some of the test output.
When in Swift 3 compatibility mode without
`-warn-swift3-objc-inference`, warn on the *uses* of declarations that
depend on the Objective-C runtime that became `@objc` due to the
deprecated inference rule. This far more directly captures important
uses of the deprecated Objective-C entrypoints. We diagnose:
* `#selector` expressions that refer to one of these `@objc` members
* `#keyPath` expressions that refer to one of these `@objc` members
* Dynamic lookup (i.e., member access via `AnyObject`) that refers to
one of these `@objc` members.
We can end up with IUOs bound as a result of overload resolution. When
this happens and the resulting type is used as a generic, we can end up
with dependent member types that fail to simplify properly as a result
of failing to substitute due to the IUO getting in the way. In these
cases it should be completely safe to strip the IUO off and retry
substitution with the base type.
This isn't really an ideal fix by any means, and we need to revisit how
we handle bindings to make it more uniform, but for now I think this is
a reasonable path to move forward.
Fixes a source compatibility regression.
rdar://problem/29960575
and provide a fix-it to move it to the new location as referenced
in SE-0081.
Fix up a few stray places in the standard library that is still using
the old syntax.
Update any ./test files that aren't expecting the new warning/fix-it
in -verify mode.
While investigating what I thought was a new crash due to this new
diagnostic, I discovered two sources of quite a few compiler crashers
related to unterminated generic parameter lists, where the right
angle bracket source location was getting unconditionally set to
the current token, even though it wasn't actually a '>'.
This commit defines the ‘Any’ keyword, implements parsing for composing
types with an infix ‘&’, and provides a fixit to convert ‘protocol<>’
- Updated tests & stdlib for new composition syntax
- Provide errors when compositions used in inheritance.
Any is treated as a contextual keyword. The name ‘Any’
is used emit the empty composition type. We have to
stop user declaring top level types spelled ‘Any’ too.
along with recent policy changes:
- For expression types that are not specifically handled, make sure to
produce a general "unused value" warning, catching a bunch of unused
values in the testsuite.
- For unused operator results, diagnose them as uses of the operator
instead of "calls".
- For calls, mutter the type of the result for greater specificity.
- For initializers, mutter the type of the initialized value.
- Look through OpenExistentialExpr's so we can handle protocol member
references propertly.
- Look through several other expressions so we handle @discardableResult
better.
Migrate the check for whether a given type is representable in
Objective-C, which is currently used to verify when @objc can be
inferred or verify that an explicitly-written @objc is well-formed,
from Sema into a set of queries on the Type within the AST library, so
it can be used in other parts of the compiler.
As part of this refactoring, clean up and improve a number of aspects
of this code:
* Unify the "trivially representable" and "representable" code paths
into a single code path that covers these cases. Clarify the
different levels of "representable" we have in both the code and
in comments.
* Distinguish between representation in C vs. representation in
Objective-C. While we aren't using this now, I'm anticipating it
being useful to allow exporting C interfaces via @_cdecl (or
similar).
* Eliminate the special cases for bridging String/Array/Dictionary/Set
with their Foundation counterparts; we now consult
_ObjectiveCBridgeable conformances exclusively to get this
information.
* Cache foreign-representation information on the ASTContext in a
manner that will let us more easily get the right answer across
different contexts while providing more sharing than the TypeChecker
version.
Annoyingly, this only seemed to fix a small class of error where we
were permitting Unsafe(Mutable)Pointer<T> to be representable in
Objective-C when T was representable but not trivially representable,
e.g., T=String or T=AnyObject.Type.
of providing contextual diagnostics (e.g. producing the warning in
Constraints/dynamic_lookup.swift). This drops a specific diagnostic about
force casting the result of as! which was added in the Swift 1.2 timeframe
to explain the change in cast semantics. Now that as! has been around for
a long time, it is more confusing than helpful.
Swift SVN r31887
- Produce more specific diagnostics relating to different kinds of invalid
- add a testcase, nfc
- Reimplement FailureDiagnosis::diagnoseGeneralMemberFailure in terms of
Not including r30787 means that we still generate bogus diagnostics like:
[1, 2, 3].doesntExist(0) // expected-error {{type 'Int2048' does not conform to protocol 'IntegerLiteralConvertible'}}
But it is an existing and separable problem from the issues addressed here.
Swift SVN r30819
r30787 causes our tests to time out; the other commits depend on r30787.
Revert "revert part of my previous patch."
Revert "Produce more specific diagnostics relating to different kinds of invalid"
Revert "add a testcase, nfc"
Revert "- Reimplement FailureDiagnosis::diagnoseGeneralMemberFailure in terms of"
Revert "Fix places in the constraint solver where it would give up once a single "
Swift SVN r30805
member references:
- Use of instance members from types
- Use of type members from instances
- Use of mutating getters.
This surely resolves some radars, but I'll have to dig them out later.
Swift SVN r30796
"unavoidable failure" path, along with Failure::DoesNotHaveNonMutatingMember and
just doing some basic disambiguation in CSDiags.
This provides some benefits:
- Allows us to plug in much more specific diagnostics for the existing "only has
mutating members" diagnostic, including producing notes for why the base expr
isn't mutable (see e.g. test/Sema/immutability.swift diffs).
- Corrects issues where we'd drop full decl name info for selector references.
- Wordsmiths diagnostics to not complain about "values of type Foo.Type" instead
complaining about "type Foo"
- Where before we would diagnose all failures with "has no member named", we now
distinguish between when there is no member, and when you can't use it. When you
can't use it, you get a vauge "cannot use it" diagnostic, but...
- This provides an infrastructure for diagnosing other kinds of problems (e.g.
trying to use a private member or a static member from an instance).
- Improves a number of cases where failed type member constraints would produce uglier
diagnostics than a different constraint failure would.
- Resolves a number of rdars, e.g. (and probably others):
<rdar://problem/20294245> QoI: Error message mentions value rather than key for subscript
Swift SVN r30715
get the same wording, fixing <rdar://problem/21964599> Different diagnostics for the same issue
While I'm in the area, remove some dead code.
Swift SVN r30713
- Have DiagnosticEngine produce "aka" annotations for sugared types.
- Fix the "optional type '@lvalue C?' cannot be used as a boolean; test for '!= nil' instead"
diagnostic to stop printing @lvalue noise.
This addresses:
<rdar://problem/19036351> QoI: Print minimally-desugared 'aka' types like Clang does
Swift SVN r30587
this is neutral w.r.t. diagnostics quality, but deletes a ton
of code:
include/swift/AST/DiagnosticsSema.def | 21 ++---------
lib/Sema/CSDiag.cpp | 64 ++--------------------------------
2 files changed, 9 insertions(+), 76 deletions(-)
Swift SVN r28956
into account accesibility, assignments to self in a non-mutating
method (consistently), recursive components of an lvalue that makes it
non-settable, etc. Now we tell you what the *problem* was, instead of
just whining.
This fixes:
<rdar://problem/19370429> QoI: fixit to add "mutating" when assigning to a member of self in a struct
<rdar://problem/17632908> QoI: Modifying struct member in non-mutating function produces difficult to understand error message
in their full generality.
Swift SVN r28867
Most tests were using %swift or similar substitutions, which did not
include the target triple and SDK. The driver was defaulting to the
host OS. Thus, we could not run the tests when the standard library was
not built for OS X.
Swift SVN r24504
rdar://problem/17198298
- Allow 'static' in protocol property and func requirements, but not 'class'.
- Allow 'static' methods in classes - they are 'class final'.
- Only allow 'class' methods in classes (or extensions of classes)
- Remove now unneeded diagnostics related to finding 'static' in previously banned places.
- Update relevant diagnostics to make the new rules clear.
Swift SVN r24260
Previously the "as" keyword could either represent coercion or or forced
downcasting. This change separates the two notions. "as" now only means
type conversion, while the new "as!" operator is used to perform forced
downcasting. If a program uses "as" where "as!" is called for, we emit a
diagnostic and fixit.
Internally, this change removes the UnresolvedCheckedCastExpr class, in
favor of directly instantiating CoerceExpr when parsing the "as"
operator, and ForcedCheckedCastExpr when parsing the "as!" operator.
Swift SVN r24253
