`Sequence._copyContents(initializing:)` is the function relied on by
`UnsafeMutableBufferPointer` for performant initialization from Collections.
Until now, `Slice<Base: Collection>` has not had its own implementation,
and therefore fell back to the default version implemented on `Sequence`.
This implementation adds an attempted fast path, using
`withContiguousStorageIfAvailable`. If that fails, the `Sequence`
algorithm is used, as before.
This resolves https://bugs.swift.org/browse/SR-14491
Introduce checking of ConcurrentValue conformances:
- For structs, check that each stored property conforms to ConcurrentValue
- For enums, check that each associated value conforms to ConcurrentValue
- For classes, check that each stored property is immutable and conforms
to ConcurrentValue
Because all of the stored properties / associated values need to be
visible for this check to work, limit ConcurrentValue conformances to
be in the same source file as the type definition.
This checking can be disabled by conforming to a new marker protocol,
UnsafeConcurrentValue, that refines ConcurrentValue.
UnsafeConcurrentValue otherwise his no specific meaning. This allows
both "I know what I'm doing" for types that manage concurrent access
themselves as well as enabling retroactive conformance, both of which
are fundamentally unsafe but also quite necessary.
The bulk of this change ended up being to the standard library, because
all conformances of standard library types to the ConcurrentValue
protocol needed to be sunk down into the standard library so they
would benefit from the checking above. There were numerous little
mistakes in the initial pass through the stsandard library types that
have now been corrected.
* [stdlib] Slice: customize withContiguous[Mutable]StorageIfAvailable
We can easily make an UnsafeBufferPointer that slices another UnsafeBufferPointer, so let’s allow Slice to vend a slice of the base collection’s contiguous storage, if it provides access to one.
We need to do some index distance calculations to implement this, but those will be constant-time in the usual case where the base collection is a RAC.
https://bugs.swift.org/browse/SR-11957
rdar://58090587
* [test] UnsafeBufferPointer: fix some warnings
* [stdlib] Slice: don’t calculate index distances unless the base provides contiguous mutable storage
* Make Range conditionally a Collection
* Convert ClosedRange to conditionally a collection
* De-gyb Range/ClosedRange, refactoring some methods.
* Remove use of Countable{Closed}Range from stdlib
* Remove Countable use from Foundation
* Fix test errors and warnings resulting from Range/CountableRange collapse
* fix prespecialize test for new mangling
* Update CoreAudio use of CountableRange
* Update SwiftSyntax use of CountableRange
* Restore ClosedRange.Index: Hashable conformance
* Move fixed typechecker slowness test for array-of-ranges from slow to fast, yay
* Apply Doug's patch to loosen test to just check for error
- Revise Equatable and Hashable for synthesized requirements
- Complete Strideable and stride(from:...:by:) documentation
- Revise DoubleWidth type docs
- Add complexity notes for Set.index(of:) and .contains(_:)
- Fix typos in Set.formUnion docs
- Add missing axioms for SetAlgebra (SR-6319)
- Improve guidance for description and debugDescription
- Add note about the result of passing duplicate keys to
Dictionary(uniqueKeysWithValues:)
- Fix typo in BinaryInteger docs
- Update Substring docs with better conversion example
- Improve docs for withMemoryRebound and isKnownUniquelyReferenced
- Add missing docs not propagated from protocols
* Eradicate IndexDistance associated type, replacing with Int everywhere
* Consistently use Int for ExistentialCollection’s IndexDistance type.
* Fix test for IndexDistance removal
* Remove a handful of no-longer-needed explicit types
* Add compatibility shims for non-Int index distances
* Test compatibility shim
* Move IndexDistance typealias into the Collection protocol
* Refactor Indices and Slice to use conditional conformance
* Replace ReversedRandomAccessCollection with a conditional extension
* Refactor some types into struct+extensions
* Revise Slice documentation
* Fix test cases for adoption of conditional conformances.
* [RangeReplaceableCollection] Eliminate unnecessary slicing subscript operator.
* Add -enable-experimental-conditional-conformances to test.
* Gruesome workaround for crasher in MutableSlice tests
See doc comments on MutableSlice for more information about what it is.
MutableSlice was one of the reasons to clarify and tighten index
invalidation rules. After that change, existing MinimalCollection
test types were performing checks that are too strict according to the
model. Existing algorithms and collections could provide them, but not
MutableSlice. This commit updates MinimalCollection types to perform
index invalidation checks that correspond to new rules.
Part of rdar://20722366. This commit adds the type, but does not wire
it up completely yet.
Swift SVN r30839
Eliminates _CollectionDefaultsType and _CollectionGeneratorDefaultsType
and creates sanity that should allow us to Protocol Extension-ize the
lazy operations, which have been blocked on inscrutable errors due in
part to the existing complexity.
Note: names beginning with "_prext_" are intended to be public after API
review and removal of the "_prext_" prefix.
Swift SVN r29689
This commit adds a minimally working Slice type and minimal tests. Even
though it might seem logical how the new protocol requirements are
injected in the CollectionType hierarchy, it is very fragile and
required many attempts to get the typechecker to finally accept it.
Because I want to ensure that the type checker does not regress, I'm
commiting a patch that does not do much yet.
Swift SVN r27665
This commit adds a minimally working Slice type and minimal tests. Even
though it might seem logical how the new protocol requirements are
injected in the CollectionType hierarchy, it is very fragile and
required many attempts to get the typechecker to finally accept it.
Because I want to ensure that the type checker does not regress, I'm
commiting a patch that does not do much yet.
Swift SVN r27617
