One minor revision: this lifts the proposed restriction against
overriding a non-open method with an open one. On reflection,
that was inconsistent with the existing rule permitting non-public
methods to be overridden with public ones. The restriction on
subclassing a non-open class with an open class remains, and is
in fact consistent with the existing access rule.
'fileprivate' is considered a broader level of access than 'private',
but for now both of them are still available to the entire file. This
is intended as a migration aid.
One interesting fallout of the "access scope" model described in
758cf64 is that something declared 'private' at file scope is actually
treated as 'fileprivate' for diagnostic purposes. This is something
we can fix later, once the full model is in place. (It's not really
/wrong/ in that they have identical behavior, but diagnostics still
shouldn't refer to a type explicitly declared 'private' as
'fileprivate'.)
As a note, ValueDecl::getEffectiveAccess will always return 'FilePrivate'
rather than 'Private'; for purposes of optimization and code generation,
we should never try to distinguish these two cases.
This should have essentially no effect on code that's /not/ using
'fileprivate' other than altered diagnostics.
Progress on SE-0025 ('fileprivate' and 'private')
Consider this code:
struct A<T> {
struct B {}
struct C<U> {}
}
Previously:
- getDeclaredType() of 'A.B' would give 'A<T>.B'
- getDeclaredTypeInContext() of 'A.B' would give 'A<T>.B'
- getDeclaredType() of 'A.C' would give 'A<T>.C'
- getDeclaredTypeInContext() of 'A.C' would give 'A<T>.C<U>'
This was causing problems for nested generics. Now, with this change,
- getDeclaredType() of 'A.B' gives 'A.B' (*)
- getDeclaredTypeInContext() of 'A.B' gives 'A<T>.B'
- getDeclaredType() of 'A.C' gives 'A.C' (*)
- getDeclaredTypeInContext() of 'A.C' gives 'A<T>.C<U>'
(Differences marked with (*)).
Also, this change makes these accessors fully lazy. Previously,
only getDeclaredTypeInContext() and getDeclaredIterfaceType()
were lazy, whereas getDeclaredType() was built from validateDecl().
Fix a few spots where the return value wasn't being checked
properly.
These functions return ErrorType if a circularity was detected via
the generic parameter list, or if the extension did not resolve.
They return Type() if the extension cannot be resolved *yet*.
This is pretty subtle, and I'll need to do another pass over
callers of these functions at some point. Many of them should be
moved over to use getSelfInContext(), getSelfOfContext() and
getSelfInterfaceType() instead.
Finally, this patch consolidates logic for diagnosting invalid
nesting of types.
The parser had some code for protocols in bad places and bad things
inside protocols, and Sema had several different bail-outs for
bad things in protocols, nested generic types, and stuff nested
inside protocol extensions.
Combine all of these into a single set of checks in Sema. Note
that we no longer give up early if we find invalid nesting.
Leaving decls unvalidated and un-type-checked only leads to
further problems. Now that all the preliminary crap has been
fixed, we can go ahead and start validating these funny nested
decls, actually fixing some crashers in the process.
Now that ConstraintSystem::openGeneric() is the only remaining
caller of this function, inline it in there and open-code the
logic.
Also, add a hack for opening nominal types contained inside
protocol types. This is invalid, but we should not crash, so
bind the type variable for the protocol 'Self' type to the
'Self' archetype, since it will not be equated with anything
otherwise.
There was a weird corner case with nested generic functions that
would fail in the SIL verifier with some nonsense about archetypes
out of context.
Fix this the "right" way, by re-working Sema function declaration
validation to assign generic signatures in a more principled way.
Previously, nested functions did not get an interface type unless
they themselves had generic parameters.
This was inconsistent with methods nested inside generic types,
which did get an interface type even if they themselves did not
have a generic parameter list.
There's some spill-over in SILGen from this change. Mostly it
makes things more consistent and fixes some corner cases.
When attempting to compile Swift 2 code (or any Swift code using the
Swift 2 names) in Swift 3, the compiler diagnostics are often entirely
useless because the names have changed radically enough that one
generally gets "no member named 'foo'" errors rather than a helpful
"'foo' was renamed to 'bar'" error. This makes for a very poor user
experience when (e.g.) trying to move Swift 2 code forward to Swift 3.
To improve the experience, when the Swift 2 and Swift 3 names of an
API differ, the Clang importer will produce a "stub" declaration that
matches the Swift 2 API. That stub will be marked with a synthesized
attribute
@available(unavailable, renamed: "the-swift-3-name")
that enables better diagnostics (e.g., "'foo' is unavailable: renamed
to 'bar') along with Fix-Its (courtesy of @jrose-apple's recent work)
that fix the Swift 2 code to compile in Swift 3.
This change addresses much of rdar://problem/25309323 (concerning QoI
of Swift 2 code compiled with a Swift 3 compiler), but some cleanup
remains.
If a function is public, and either @_transparent or @inline(__always),
we need to make its body available for inlining in other resilience
domains. The more general concept here is an 'inlineable' function;
once the precise behaviors we want are nailed down, the set of AST
attributes for exposing this will likely change.
At the SIL level, inlineable functions are marked with the [fragile]
attribute. The SIL serializer only serializes [fragile] functions
unless -sil-serialize-all is passed in.
This patch fixes two problems in this area by consolidating some
duplicated logic:
1) Property accesses in Sema did not check for @inline(__always)
functions, or functions nested inside inlineable functions.
This manifested as IRGen crashes if an inlineable function
accessed a property of a resilient type.
2) In SILGen, functions nested inside [fragile] functions were
properly [fragile], but @inline(__always) was not taken into
account. This manifested as SIL serializer crashes where a
[fragile] function could reference a non-public, non-[fragile]
function.
This change is part of the series for building the standard library
without -sil-serialize-all.
There's a group of methods in `DeclContext` with names that start with *is*,
such as `isClassOrClassExtensionContext()`. These names suggests a boolean
return value, while the methods actually return a type declaration. This
patch replaces the *is* prefix with *getAs* to better reflect their interface.
Fills in Chris's placeholder in feace85d5. I'm not quite sure why a private
subscript doesn't produce a non-cascading dependency right now, but this is
at least conservatively correct.
(For more infomation on dependencies, check out "Dependency Analysis.rst".)
This is necessary for some other work I'm doing, which really wants
paramdecls to have reasonable declcontexts. It is also a small step
towards generic subscripts.
Rather than plumbing a "has missing required members" flag all the way
through the LazyResolver's loadAllMembers and its implementations,
just eagerly update the "has missing required members" flag in the
Clang importer when it happens. More NFC cleanup.
Previously, methods on DeclContext for getting generic parameters
and signatures did not walk up from type contexts to function
contexts, or function contexts to function contexts.
Presumably this is because SIL doesn't completely support nested
generics yet, instead only handling these two special cases:
- non-generic local function inside generic function
- generic method inside generic type
For local functions nested inside generic functions, SIL expects
the closure to not have an interface type or generic signature,
even if the contextual type signature contains archetypes.
This should probably be revisited some day.
Recall that these cases are explicitly rejected by Sema diagnostics
because they lack SIL support:
- generic function inside generic function
- generic type inside generic function
After the previous patches in this series, it becomes possible to
construct types that are the same as before for the supported uses of
nested generics, while introducing a more self-consistent conceptual
model for the unsupported cases.
Some new tests show we generate diagnotics in various cases that
used to crash.
The conceptual model might still not be completely right, and of
course SIL, IRGen and runtime support is still missing.
Now that generic signatures of types include generic parameters
introduced by outer generic functions, we need to know to skip
them when forming bound generic types or substitutions.
Add a function that computes the depth of the innermost generic
context that is not a generic type context.
Once nested generic parameter lists are properly chained, we need a
way of checking if we're inside a generic type context that's
distinct from just checking if we have a generic type signature
available.
This distinguishes between these two cases:
class A<T> {
// generic signature
func method() -> T { // <T> A<T> -> () -> T
}
}
func f<T>() {
class A {
// no generic signature
func method() -> T { // A -> () -> T
}
}
}
For better or worse, the type of a function can end up as ErrorType,
and the generic signature was not stored anywhere else, causing
crashes from orphaned generic type parameters.
This patch is the first in a series to make this more robust by
storing the generic signature before the interface type is computed.
This is more complex than it could be if ExtensionDecl and NominalTypeDecl
had a common ancestor in the Decl hierarchy, however this is not possible
right now because TypeDecl inherits from ValueDecl.
Fixes <rdar://problem/20981254>.
Swift SVN r28941
Also allow cast<> from any Decl to DeclContext, not just ValueDecl.
An example of a Decl that is a DeclContext but not a ValueDecl is
ExtensionDecl.
The const_cast<> hack is horrid but its needed to deal with both const
and non-const operands in the patch that eventually uses this.
Note that this adds an explicit 'const auto' to the prior usage of
cast<DeclContext> in Mangling.cpp.
NFC
Progress on <rdar://problem/20981254>.
Swift SVN r28929
Resolve extensions when we need them, but don't bother when we
don't. Among other things, this lets us identify a protocol extension
before it's been fully validated. No behavior change for anything we
have written now.
Swift SVN r28891
Modules occupy a weird space in the AST now: they can be treated like
types (Swift.Int), which is captured by ModuleType. They can be
treated like values for disambiguation (Swift.print), which is
captured by ModuleExpr. And we jump through hoops in various places to
store "either a module or a decl".
Start cleaning this up by transforming Module into ModuleDecl, a
TypeDecl that's implicitly created to describe a module. Subsequent
changes will start folding away the special cases (ModuleExpr ->
DeclRefExpr, name lookup results stop having a separate Module case,
etc.).
Note that the Module -> ModuleDecl typedef is there to limit the
changes needed. Much of this patch is actually dealing with the fact
that Module used to have Ctx and Name public members that now need to
be accessed via getASTContext() and getName(), respectively.
Swift SVN r28284
Implement simplistic partial ordering rules for members of protocol
extensions. Specifically:
- A member of a concrete type is more specialized than a member of a
protocol extension
- A member of a protocol extension of P1 is more specialized than a
member of a protocol extension of P2 if P1 inherits from P2
This achieves most of what rdar://problem/20335936 covers, but does
not yet handle ordering between constrained protocol extensions.
Swift SVN r26723
Remove the semantic restrictions that prohibited extensions of
protocol types, and start making some systematic changes so that
protocol extensions start to make sense:
- Replace a lot of occurrences of isa<ProtocolDecl> and
dyn_cast<ProtocolDecl> on DeclContexts to use the new
DeclContext::isProtocolOrProtocolExtensionContext(), where we want
that behavior to apply equally to protocols and protocol extensions.
- Eliminate ProtocolDecl::getSelf() in favor of
DeclContext::getProtocolSelf(), which produces the appropriate
generic type parameter for the 'Self' of a protocol or protocol
extension. Update all of the callers of ProtocolDecl::getSelf()
appropriately.
- Update extension validation to appropriately form generic
parameter lists for protocol extensions.
- Methods in protocol extensions always use the witnesscc calling
convention.
At this point, we can type check and SILGen very basic definitions of
protocol extensions with methods that can call protocol requirements,
generic free functions, and other methods within the same protocol
extension.
Regresses four compiler crashers but improves three compiler
crashers... we'll call that "progress"; the four regressions all hit
the same assertion in the constraint system that will likely be
addressed as protocol extensions starts working.
Swift SVN r26579
Currently a no-op, but effective access for entities within the current
module will soon need to take testability into account. This declaration:
internal func foo() {}
has a formal access of 'internal', but an effective access of 'public' if
we're in a testable mode.
Part of rdar://problem/17732115 (testability)
Swift SVN r26472
When code completing a literal expr, it is likely that code completion engine only collects the expr
that is not fully type checked. Therefore, no members of the literal can be suggested. To address this,
we try to climb up expr hierarchy in AST to find an expr with a nominal type, and use the nominal type
to finish code completion.
rdar://20059173
Swift SVN r26116
The contract for LazyResolver::loadAllMembers() was that the caller
would handle actually adding the members, since it was an iterable
declaration context and could centralize that (simple) logic. However,
this fails in the Clang importer in rare but amusing ways when some of
the deferred actions (e.g., finishing a protocol conformance) depend
on having the members already set. The deferred action occurs after
the member list is complete in ClangImporter's loadAllMembers(), but
before its caller actual set the member list, leaving incomplete
conformances. Fixes rdar://problem/18884272.
Swift SVN r25630
This commit validates @availability() attribute version ranges to ensure that
a declaration is not more available than its lexically containing scope. To do so,
we find the inner-most declaration containing an @availability attribute that itself
has an @availability attribute and check that first attribute's available
version range is contained in the enclosing declaration's available range. If not,
we emit a diagnostic.
This commit removes a FIXME for checking @availability and overrides. It appears that
the FIXME is a copy/paste to/from AttributeOverrideChecker, where it still resides.
Swift SVN r25453
Local type declarations are saved in the source file during parsing,
now serialized as decls. Some of these may be defined in DeclContexts
which aren't Decls and previously weren't serialized. Create four new
record kinds:
* PatternBindingInitializer
* DefaultArgumentInitializer
* AbstractClosureExpr
* TopLevelCodeDecl
These new records are used to only preserve enough information for
remangling in the debugger, and parental context relationships.
Finally, provide a lookup API in the module to search by mangled name.
With the new remangling API, the debugging lifecycle for local types
should be complete.
The extra LOCAL_CONTEXT record will compressed back down in a
subsequent patch.
Swift SVN r24739
Changing the design of this to maintain more local context
information and changing the lookup API.
This reverts commit 4f2ff1819064dc61c20e31c7c308ae6b3e6615d0.
Swift SVN r24432
rdar://problem/18295292
Locally scoped type declarations were previously not serialized into the
module, which meant that the debugger couldn't reason about the
structure of instances of those types.
Introduce a new mangling for local types:
[file basename MD5][counter][identifier]
This allows the demangle node's data to be used directly for lookup
without having to backtrack in the debugger.
Local decls are now serialized into a LOCAL_TYPE_DECLS table in the
module, which acts as the backing hash table for looking up
[file basename MD5][counter][identifier] -> DeclID mappings.
New tests:
* swift-ide-test mode for testing the demangle/lookup/mangle lifecycle
of a module that contains local decls
* mangling
* module merging with local decls
Swift SVN r24426
"private" is a very overloaded term already. "Cascading" instead of
"non-private" is a bit more clear about what will happen with this sort
of lookup.
No functionality change. There are some double negatives I plan to clean
up in the next commit, but this one was supposed to be very mechanical.
Swift SVN r23969
This adds a check to isPrivateContextForLookup, and also changes Sema to
use a function itself as the lookup context for non-generic functions'
result types (like generic functions already do). It also moves
isPrivateContextForLookup onto DeclContext itself, to be used in the next
commits.
Swift SVN r23633
Have them fill out a vector provided by the caller instead.
It is very easy to have callers just go through the array, thus wasting memory, as
the clang importer ended up doing.
The caller should be the one deciding if the array must be copied in ASTContext or not.
Swift SVN r23472
