[stdlib] Change Indexable deprecation messages

It's important to let people know that, in contrast with existing
practice in other frameworks, we really are going to remove the
deprecated API, and soon.

Author: Dave Abrahams

stdlib/public/core/BidirectionalCollection.swift

@@ -16,7 +16,7 @@
 /// In most cases, it's best to ignore this protocol and use the
 /// `BidirectionalCollection` protocol instead, because it has a more complete
 /// interface.
-@available(*, deprecated, renamed: "BidirectionalCollection")
+@available(*, deprecated, message: "it will be removed in Swift 4.0.  Please use 'BidirectionalCollection' instead")
 public protocol BidirectionalIndexable : Indexable {
   // FIXME(ABI)(compiler limitation): there is no reason for this protocol
   // to exist apart from missing compiler features that we emulate with it.

stdlib/public/core/Collection.swift

@@ -15,7 +15,7 @@
 ///
 /// In most cases, it's best to ignore this protocol and use the `Collection`
 /// protocol instead, because it has a more complete interface.
-@available(*, deprecated, renamed: "Collection")
+@available(*, deprecated, message: "it will be removed in Swift 4.0.  Please use 'Collection' instead")
 public protocol IndexableBase {
   // FIXME(ABI)(compiler limitation): there is no reason for this protocol
   // to exist apart from missing compiler features that we emulate with it.
@@ -157,7 +157,7 @@ public protocol IndexableBase {
 ///
 /// In most cases, it's best to ignore this protocol and use the `Collection`
 /// protocol instead, because it has a more complete interface.
-@available(*, deprecated, renamed: "Collection")
+@available(*, deprecated, message: "it will be removed in Swift 4.0.  Please use 'Collection' instead")
 public protocol Indexable : IndexableBase {
   /// A type used to represent the number of steps between two indices, where
   /// one value is reachable from the other.

stdlib/public/core/MutableCollection.swift

@@ -15,7 +15,7 @@
 /// In most cases, it's best to ignore this protocol and use the
 /// `MutableCollection` protocol instead, because it has a more complete
 /// interface.
-@available(*, deprecated, renamed: "MutableCollection")
+@available(*, deprecated, message: "it will be removed in Swift 4.0.  Please use 'MutableCollection' instead")
 public protocol MutableIndexable : Indexable {
   // FIXME(ABI)(compiler limitation): there is no reason for this protocol
   // to exist apart from missing compiler features that we emulate with it.

stdlib/public/core/RandomAccessCollection.swift

@@ -15,7 +15,7 @@
 /// In most cases, it's best to ignore this protocol and use the
 /// `RandomAccessCollection` protocol instead, because it has a more complete
 /// interface.
-@available(*, deprecated, renamed: "RandomAccessCollection")
+@available(*, deprecated, message: "it will be removed in Swift 4.0.  Please use 'RandomAccessCollection' instead")
 public protocol RandomAccessIndexable : BidirectionalIndexable {
   // FIXME(ABI)(compiler limitation): there is no reason for this protocol
   // to exist apart from missing compiler features that we emulate with it.

stdlib/public/core/RangeReplaceableCollection.swift.gyb

@@ -22,7 +22,7 @@
 /// In most cases, it's best to ignore this protocol and use the
 /// `RangeReplaceableCollection` protocol instead, because it has a more
 /// complete interface.
-@available(*, deprecated, renamed: "RangeReplaceableCollection")
+@available(*, deprecated, message: "it will be removed in Swift 4.0.  Please use 'RandomAccessCollection' instead")
 public protocol RangeReplaceableIndexable : Indexable {
   // FIXME(ABI)(compiler limitation): there is no reason for this protocol
   // to exist apart from missing compiler features that we emulate with it.

validation-test/stdlib/CollectionDiagnostics.swift

@@ -54,8 +54,7 @@ func sortResultIgnored<
   array.sorted { $0 < $1 } // expected-warning {{result of call to 'sorted(by:)' is unused}}
 }
 
-// expected-warning@+2 {{'Indexable' is deprecated: renamed to 'Collection'}}
-// expected-note@+1 {{use 'Collection' instead}}
+// expected-warning@+1 {{'Indexable' is deprecated: it will be removed in Swift 4.0.  Please use 'Collection' instead}}
 struct GoodIndexable : Indexable { 
   func index(after i: Int) -> Int { return i + 1 }
   var startIndex: Int { return 0 }
@@ -66,8 +65,7 @@ struct GoodIndexable : Indexable {
 }
 
 
-// expected-warning@+3 {{'Indexable' is deprecated: renamed to 'Collection'}}
-// expected-note@+2 {{use 'Collection' instead}}
+// expected-warning@+2 {{'Indexable' is deprecated: it will be removed in Swift 4.0.  Please use 'Collection' instead}}
 // expected-error@+1 {{type 'BadIndexable1' does not conform to protocol 'IndexableBase'}}
 struct BadIndexable1 : Indexable {
   func index(after i: Int) -> Int { return i + 1 }
@@ -79,8 +77,7 @@ struct BadIndexable1 : Indexable {
   // Missing 'subscript(_:) -> SubSequence'.
 }
 
-// expected-warning@+3 {{'Indexable' is deprecated: renamed to 'Collection'}}
-// expected-note@+2 {{use 'Collection' instead}}
+// expected-warning@+2 {{'Indexable' is deprecated: it will be removed in Swift 4.0.  Please use 'Collection' instead}}
 // expected-error@+1 {{type 'BadIndexable2' does not conform to protocol 'IndexableBase'}}
 struct BadIndexable2 : Indexable {
   var startIndex: Int { return 0 }
@@ -91,8 +88,7 @@ struct BadIndexable2 : Indexable {
   // Missing index(after:) -> Int
 }
 
-// expected-warning@+2 {{'BidirectionalIndexable' is deprecated: renamed to 'BidirectionalCollection'}}
-// expected-note@+1 {{use 'BidirectionalCollection' instead}}
+// expected-warning@+1 {{'BidirectionalIndexable' is deprecated: it will be removed in Swift 4.0.  Please use 'BidirectionalCollection' instead}}
 struct GoodBidirectionalIndexable1 : BidirectionalIndexable {
   var startIndex: Int { return 0 }
   var endIndex: Int { return 0 }
@@ -105,8 +101,7 @@ struct GoodBidirectionalIndexable1 : BidirectionalIndexable {
 
 // We'd like to see: {{type 'BadBidirectionalIndexable' does not conform to protocol 'BidirectionalIndexable'}}
 // But the compiler doesn't generate that error.
-// expected-warning@+2 {{'BidirectionalIndexable' is deprecated: renamed to 'BidirectionalCollection'}}
-// expected-note@+1 {{use 'BidirectionalCollection' instead}}
+// expected-warning@+1 {{'BidirectionalIndexable' is deprecated: it will be removed in Swift 4.0.  Please use 'BidirectionalCollection' instead}}
 struct BadBidirectionalIndexable : BidirectionalIndexable {
   var startIndex: Int { return 0 }
   var endIndex: Int { return 0 }