[stdlib] Use [Closed]Range.init(_uncheckedBounds:) in more places

When the stdlib says not to check, it’s a good idea to actually not have any checking, so that we leave existing code paths unchanged. (And because we do trust that the stdlib is responsible about such things.)

Author: lorentey

stdlib/public/core/ClosedRange.swift

@@ -107,8 +107,9 @@ extension ClosedRange: RangeExpression {
   public func relative<C: Collection>(to collection: C) -> Range<Bound>
   where C.Index == Bound {
     return Range(
-      uncheckedBounds: (
-        lower: lowerBound, upper: collection.index(after: self.upperBound)))
+      _uncheckedBounds: (
+        lower: lowerBound,
+        upper: collection.index(after: self.upperBound)))
   }
 
   /// Returns a Boolean value indicating whether the given element is contained
@@ -430,7 +431,7 @@ extension ClosedRange {
       limits.upperBound < self.upperBound ? limits.upperBound
           : limits.lowerBound > self.upperBound ? limits.lowerBound
           : self.upperBound
-    return ClosedRange(uncheckedBounds: (lower: lower, upper: upper))
+    return ClosedRange(_uncheckedBounds: (lower: lower, upper: upper))
   }
 }
 
@@ -446,7 +447,7 @@ extension ClosedRange where Bound: Strideable, Bound.Stride: SignedInteger {
   public init(_ other: Range<Bound>) {
     _precondition(!other.isEmpty, "Can't form an empty closed range")
     let upperBound = other.upperBound.advanced(by: -1)
-    self.init(uncheckedBounds: (lower: other.lowerBound, upper: upperBound))
+    self.init(_uncheckedBounds: (lower: other.lowerBound, upper: upperBound))
   }
 }
 
@@ -483,7 +484,7 @@ extension ClosedRange: Decodable where Bound: Decodable {
           codingPath: decoder.codingPath,
           debugDescription: "Cannot initialize \(ClosedRange.self) with a lowerBound (\(lowerBound)) greater than upperBound (\(upperBound))"))
     }
-    self.init(uncheckedBounds: (lower: lowerBound, upper: upperBound))
+    self.init(_uncheckedBounds: (lower: lowerBound, upper: upperBound))
   }
 }
 

stdlib/public/core/Range.swift

@@ -315,7 +315,7 @@ extension Range where Bound: Strideable, Bound.Stride: SignedInteger {
   /// require an upper bound of `Int.max + 1`, which is not representable as
   public init(_ other: ClosedRange<Bound>) {
     let upperBound = other.upperBound.advanced(by: 1)
-    self.init(uncheckedBounds: (lower: other.lowerBound, upper: upperBound))
+    self.init(_uncheckedBounds: (lower: other.lowerBound, upper: upperBound))
   }
 }
 
@@ -332,7 +332,7 @@ extension Range: RangeExpression {
   @inlinable // trivial-implementation
   public func relative<C: Collection>(to collection: C) -> Range<Bound>
   where C.Index == Bound {
-    return Range(uncheckedBounds: (lower: lowerBound, upper: upperBound))
+    self
   }
 }
 
@@ -366,7 +366,7 @@ extension Range {
       limits.upperBound < self.upperBound ? limits.upperBound
           : limits.lowerBound > self.upperBound ? limits.lowerBound
           : self.upperBound
-    return Range(uncheckedBounds: (lower: lower, upper: upper))
+    return Range(_uncheckedBounds: (lower: lower, upper: upper))
   }
 }
 
@@ -442,7 +442,7 @@ extension Range: Decodable where Bound: Decodable {
           codingPath: decoder.codingPath,
           debugDescription: "Cannot initialize \(Range.self) with a lowerBound (\(lowerBound)) greater than upperBound (\(upperBound))"))
     }
-    self.init(uncheckedBounds: (lower: lowerBound, upper: upperBound))
+    self.init(_uncheckedBounds: (lower: lowerBound, upper: upperBound))
   }
 }
 

stdlib/public/core/StringProtocol.swift

@@ -153,7 +153,7 @@ extension StringProtocol {
       let end = endIndex
       _internalInvariant(
         start.transcodedOffset == 0 && end.transcodedOffset == 0)
-      return Range(uncheckedBounds: (start._encodedOffset, end._encodedOffset))
+      return Range(_uncheckedBounds: (start._encodedOffset, end._encodedOffset))
     }
   }
 

stdlib/public/core/StringStorageBridge.swift

@@ -30,7 +30,7 @@ extension _AbstractStringStorage {
                   "Range out of bounds")
 
     let range = Range(
-      uncheckedBounds: (aRange.location, aRange.location+aRange.length))
+      _uncheckedBounds: (aRange.location, aRange.location+aRange.length))
     let str = asString
     str._copyUTF16CodeUnits(
       into: UnsafeMutableBufferPointer(start: buffer, count: range.count),