* AttributedString index validity APIs
* Move canImport(Synchronization) into function body
* Remove unnecessary bounds checks from validity expression
* Update FOUNDATION_FRAMEWORK code to provide Index versions
This PR implements the API changes proposed in SF-0014 by adding a new DiscontiguousAttributedSubstring type (the result of slicing an AttributedString with a RangeSet) which vends out slices of each underlying view, an upgraded Runs view which now handles discontiguous segments, and performs operations over the discontiguous subranges.
`AttributedString` goes out of its way to emulate the stdlib’s behavior for `String` slicing. Unfortunately, it went a little overboard:
```swift
import Foundation
let str1 = "F\u{301}a\u{308}n\u{303}c\u{327}y\u{30a}" // "F́äñçẙ"
let str2 = AttributedString(str1)
let substr1 = str1[...str1.startIndex] // “F\u{301}”
let substr2 = str2[...str2.startIndex] // “F”
print(Array(substr1.unicodeScalars))
print(Array(substr2.unicodeScalars))
```
We expect slicing on range expressions to always produce consistent results between `String` and `AttributedString`.
When slicing character-based string views on `…str.startIndex`, we naturally expect the range expression to cover the entire first `Character`, and that is precisely what `String` does.
`AttributedString`’s default view is not as obviously `Character`-based as `String` is, but emulating the stdlib’s behavior is much preferable than to allow such simple, character-aligned range expressions to slice the attributed string at random sub-character positions.
* Implement unlocalized range(of:) for AttributedString
`String` has a natively-implemented `_range(of:options:)`. This PR implements `AttributedString`'s `range(of:options:)` with that when localization support is not needed.
Ideally we should implement this on `BigString` to avoid iterating through `Characters`, which is tracked as a future TODO.
This function takes a `Locale` argument, which isn't available in FoundationEssentials. We could move this to FoundationInternalization where `Locale` is defined, but some clients use it with `locale: nil` and do not need localized results. To make the best of this let's add a non-localized version for FoundationEssentials.
* Enable AttributedString.range(of:) when locale is nil
* rdar://108152217 Start using Rope for attribute run storage
- Replace `Array<_InternalRun>` with `Rope<_InternalRun>`.
- Fix semantics of AttributeRunBoundaries.character. It no longer pretends that attributes can be tied to grapheme clusters — that never actually worked properly, and it cannot be supported without breaking the intended use case.
- Remove cache of latest run position; log(n) might be fast enough that we don’t need to worry about that.
- Switch AttributedString.Guts members to take/return BigString.Index values, not AttributedString indices. This cuts down on constant back-and-forth conversions.
- Discard unused Guts members; update remaining mutation methods to follow Swift naming conventions.
- Stop using the `public extension` language misfeature.
* rdar://108152217 Apply notes from code review
AttributedString.CharacterView and AttributedString.UnicodeScalarView
did not use the right semantics in the case when the underlying text
was not touched. It’s okay in that case to not mutate text storage,
but we still want to override the attributes within the subrange as if
the client actually did replace text — as in, we want to use precisely
the same attribute storage for the range on both paths.
Also, make sure we correctly enforce attribute constraints in the
`!hasStringChanges` case, in both views.
* rdar://108152217 Fix logic error in AttributedString.Runs.subscript
(Discovered during code review.)
* rdar://108152217 Clean up CharacterView/UnicodeScalarView mutations & update failing test
* rdar://108152217 Apply review notes
* Revert "Create FoundationInternals, an internal module to host shared files used by FoundationInternationalization and FoundationEssentials (#101)"
This reverts commit 8f08a649db1f3eb31593cdae7a30c5e95cb614a7.
* Reapply fb718cd3fb9f058a5fd6d736cec9c2b99d6f7dc6 fix to the other restored LockedState
* Create FoundationInternals, an internal module to host shared files used by FoundationInternationalization and FoundationEssentials
- Modules will access FoundationInternals types with `package import FoundationInternals`. This is currently an experimental feature of `AccessLevelOnImport`.
- Move `LockedState` to FoundationInternals and publicize functions needed by other modules.
* rdar://105027055: Do not use as-casts in specializations.
Introduce _specializingCast and use it instead of `as?`-casts inside
if ladders that implement generic specialization.
`as?` invokes undesirable runtime machinery such as bridging checks.
* rdar://105027055: Ensure AttributedString views have properly aligned bounds
* rdar://105027055: Implement index(_:offsetBy:limitedBy:) in AttributedString views
We have agreed that `agreeWithArgument` sounds more intuitive to localizers than
`agreeWithReplacement`. This attribute hasn't been adopted internally yet, so we
can afford to rename it just before the SDK freeze.
* (101354563) Separate CodableWithConfiguration into standalone file
* (101354563) Update PredicateExpression archive formats
* (101354563) Codable Support for Predicate
* (101354563) Assert on unsupported keypaths
* rdar://107778676 Stop vendoring the Collections package
* rdar://107778676 Fix test expectation
AttributedString.CharacterView needs to round all indices down to the
nearest Character boundary to avoid semantic issues with its
Collection conformance. This means that CharacterView slices can never
start or end in between Character boundaries.
* Remove a stray print statement
