Modify diagnostics to suggest updating existing available attribute

include/swift/AST/DiagnosticsSema.def

@@ -6649,6 +6649,9 @@ ERROR(availability_variadic_type_only_version_newer, none,
 NOTE(availability_guard_with_version_check, none,
      "add 'if #available' version check", ())
 
+NOTE(update_availability_attribute, none,
+     "change the @available attribute of the %0 on %1 from %2 to %3", (DescriptiveDeclKind, StringRef, StringRef, StringRef))
+
 NOTE(availability_add_attribute, none,
      "add @available attribute to enclosing %0", (DescriptiveDeclKind))
 FIXIT(insert_available_attr,

lib/Sema/TypeCheckAvailability.cpp

@@ -1821,18 +1821,30 @@ static void fixAvailabilityForDecl(SourceRange ReferenceRange, const Decl *D,
   if (TypeChecker::diagnosticIfDeclCannotBePotentiallyUnavailable(D).has_value())
     return;
 
-  if (getActiveAvailableAttribute(D, Context)) {
-    // For QoI, in future should emit a fixit to update the existing attribute.
-    return;
-  }
-
   // For some declarations (variables, enum elements), the location in concrete
   // syntax to suggest the Fix-It may differ from the declaration to which
   // we attach availability attributes in the abstract syntax tree during
   // parsing.
   const Decl *ConcDecl = concreteSyntaxDeclForAvailableAttribute(D);
 
   DescriptiveDeclKind KindForDiagnostic = ConcDecl->getDescriptiveKind();
+
+  if (auto Attr = getActiveAvailableAttribute(D, Context)) {
+    if (Attr->isUnconditionallyUnavailable()) {
+      return;
+    }
+    SourceManager &SM = Context.SourceMgr;
+    auto Version = SM.extractText(Lexer::getCharSourceRangeFromSourceRange(
+                                      SM, Attr->IntroducedRange))
+                       .str();
+    auto Required = RequiredRange.getLowerEndpoint().getAsString();
+    Context.Diags
+        .diagnose(ReferenceRange.Start, diag::update_availability_attribute,
+                  KindForDiagnostic, Attr->platformString(), Version, Required)
+        .fixItReplace(Attr->IntroducedRange, Required);
+    return;
+  }
+
   SourceLoc InsertLoc;
 
   // To avoid exposing the pattern binding declaration to the user, get the

test/Concurrency/sendable_checking.swift

@@ -51,6 +51,7 @@ func testCV(
 
   acceptCV(ns3) // expected-warning {{conformance of 'NS3' to 'Sendable' is only available in macOS 11.0 or newer}}
   // expected-note @-1 {{add 'if #available' version check}}
+  // expected-note @-2 {{change the @available attribute of the global function on macOS from 10.15 to 11.0}}
 
   acceptCV(ns4) // expected-complete-and-tns-warning {{type 'NS4' does not conform to the 'Sendable' protocol}}
 
@@ -71,6 +72,7 @@ func testCV(
   acceptCV(ns2) // expected-warning{{type 'NS2' does not conform to the 'Sendable' protocol}}
   acceptCV(ns3) // expected-warning{{conformance of 'NS3' to 'Sendable' is only available in macOS 11.0 or newer}}
   // expected-note@-1{{add 'if #available' version check}}
+  // expected-note @-2 {{change the @available attribute of the global function on macOS from 10.15 to 11.0}}
   acceptCV(ns4) // expected-warning{{type 'NS4' does not conform to the 'Sendable' protocol}}
   acceptCV(fn) // expected-warning{{type '() -> Void' does not conform to the 'Sendable' protocol}}
   // expected-note@-1{{a function type must be marked '@Sendable' to conform to 'Sendable'}}

test/Sema/api-availability-only.swift

@@ -10,4 +10,5 @@ public struct S {}
 public func newFunc() {
   _ = S() // expected-error {{'S' is only available in}}
   // expected-note @-1 {{add 'if #available' version check}}
+  // expected-note @-2 {{change the @available attribute of the global function on macOS from 10.51 to 10.52}} {{9:18-23=10.52}}
 }

test/Sema/availability_define.swift

@@ -59,6 +59,7 @@ func client() {
   onMacOS10_15()
   onMacOS11_0() // expected-error {{is only available in macOS 11.0 or newer}}
   // expected-note @-1 {{add 'if #available' version check}}
+  // expected-note @-2 {{change the @available attribute of the global function on macOS from 10.15 to 11.0}}
   onMacOSDeprecated()
 
   if #available(_iOS14Aligned, *) {
@@ -68,6 +69,7 @@ func client() {
   if #unavailable(_iOS14Aligned) {
     onMacOS11_0() // expected-error {{is only available in macOS 11.0 or newer}}
     // expected-note @-1 {{add 'if #available' version check}}
+    // expected-note @-2 {{change the @available attribute of the global function on macOS from 10.15 to 11.0}}
   } else {
     onMacOS11_0()
   }

test/Sema/availability_swiftui.swift

@@ -13,3 +13,4 @@ class AnyColorBox: LessAvailable {} // Ok, exception specifically for AnyColorBo
 @available(macOS 10.15, *)
 @usableFromInline
 class OtherClass: LessAvailable {} // expected-error {{'LessAvailable' is only available in macOS 11 or newer; clients of 'SwiftUI' may have a lower deployment target}}
+// expected-note @-1 {{change the @available attribute of the class on macOS from 10.15 to 11}} {{13:18-23=11}}

test/Sema/availability_versions.swift

@@ -55,6 +55,7 @@ func functionAvailableOn10_51() {
 
   let _: Int = globalFuncAvailableOn10_52() // expected-error {{'globalFuncAvailableOn10_52()' is only available in macOS 10.52 or newer}}
       // expected-note@-1 {{add 'if #available' version check}}
+      // expected-note@-2 {{change the @available attribute of the global function on macOS from 10.51 to 10.52}} {{43:29-34=10.52}}
 }
 
 // Still allow other availability annotations on script-mode globals
@@ -327,7 +328,8 @@ class ClassWithPotentiallyUnavailableProperties {
     get {
       let _: Int = availableOn10_51Stored // expected-error {{'availableOn10_51Stored' is only available in macOS 10.51 or newer}}
           // expected-note@-1 {{add 'if #available' version check}}
-
+          // expected-note@-2 {{change the @available attribute of the pattern binding on macOS from 10.9 to 10.51}} {{326:31-35=10.51}}
+
       if #available(OSX 10.51, *) {
         let _: Int = availableOn10_51Stored
       }
@@ -409,10 +411,12 @@ class ClassWithReferencesInInitializers {
   var propWithInitializer10_51: Int = globalFuncAvailableOn10_51()
 
   var propWithInitializer10_52: Int = globalFuncAvailableOn10_52() // expected-error {{'globalFuncAvailableOn10_52()' is only available in macOS 10.52 or newer}}
+    // expected-note@-1 {{change the @available attribute of the class on macOS from 10.51 to 10.52}} {{409:29-34=10.52}}
 
   lazy var lazyPropWithInitializer10_51: Int = globalFuncAvailableOn10_51()
 
   lazy var lazyPropWithInitializer10_52: Int = globalFuncAvailableOn10_52() // expected-error {{'globalFuncAvailableOn10_52()' is only available in macOS 10.52 or newer}}
+    // expected-note@-1 {{change the @available attribute of the class on macOS from 10.51 to 10.52}} {{409:29-34=10.52}}
 }
 
 func accessPotentiallyUnavailableProperties(_ o: ClassWithPotentiallyUnavailableProperties) {
@@ -522,6 +526,7 @@ enum EnumIntroducedOn10_52 {
 
 @available(OSX, introduced: 10.51)
 enum CompassPoint {
+
   case North
   case South
   case East
@@ -540,9 +545,11 @@ enum CompassPoint {
   case WithAvailableByEnumElementPayload1(p : EnumIntroducedOn10_52), WithAvailableByEnumElementPayload2(p : EnumIntroducedOn10_52)
 
   case WithPotentiallyUnavailablePayload(p : EnumIntroducedOn10_52) // expected-error {{'EnumIntroducedOn10_52' is only available in macOS 10.52 or newer}}
+    // expected-note@-1 {{change the @available attribute of the enum on macOS from 10.51 to 10.52}} {{527:29-34=10.52}}
 
   case WithPotentiallyUnavailablePayload1(p : EnumIntroducedOn10_52), WithPotentiallyUnavailablePayload2(p : EnumIntroducedOn10_52) // expected-error 2{{'EnumIntroducedOn10_52' is only available in macOS 10.52 or newer}}
-
+    // expected-note@-1 2{{change the @available attribute of the enum on macOS from 10.51 to 10.52}} {{527:29-34=10.52}}
+
   @available(OSX, unavailable)
   case WithPotentiallyUnavailablePayload3(p : EnumIntroducedOn10_52)
 }
@@ -878,18 +885,20 @@ class SubWithLargerMemberAvailability : SuperWithLimitedMemberAvailability {
   override func someMethod() {
     super.someMethod() // expected-error {{'someMethod()' is only available in macOS 10.51 or newer}}
         // expected-note@-1 {{add 'if #available' version check}}
-
+        // expected-note@-2 {{change the @available attribute of the instance method on macOS from 10.9 to 10.51}} {{884:31-35=10.51}}
+
     if #available(OSX 10.51, *) {
       super.someMethod()
     }
   }
 
   @available(OSX, introduced: 10.9)
   override var someProperty: Int {
-    get { 
+    get {
       let _ = super.someProperty // expected-error {{'someProperty' is only available in macOS 10.51 or newer}}
-          // expected-note@-1 {{add 'if #available' version check}}
-
+        // expected-note@-1 {{add 'if #available' version check}}
+        // expected-note@-2 {{change the @available attribute of the pattern binding on macOS from 10.9 to 10.51}} {{895:31-35=10.51}}
+
       if #available(OSX 10.51, *) {
         let _ = super.someProperty
       }
@@ -961,6 +970,7 @@ protocol ProtocolAvailableOn10_51 {
 
 @available(OSX, introduced: 10.9)
 protocol ProtocolAvailableOn10_9InheritingFromProtocolAvailableOn10_51 : ProtocolAvailableOn10_51 { // expected-error {{'ProtocolAvailableOn10_51' is only available in macOS 10.51 or newer}}
+  // expected-note@-1 {{change the @available attribute of the protocol on macOS from 10.9 to 10.51}} {{971:29-33=10.51}}
 }
 
 @available(OSX, introduced: 10.51)
@@ -973,6 +983,7 @@ protocol UnavailableProtocolInheritingFromProtocolAvailableOn10_51 : ProtocolAva
 
 @available(OSX, introduced: 10.9)
 class SubclassAvailableOn10_9OfClassAvailableOn10_51 : ClassAvailableOn10_51 { // expected-error {{'ClassAvailableOn10_51' is only available in macOS 10.51 or newer}}
+  // expected-note@-1 {{change the @available attribute of the class on macOS from 10.9 to 10.51}} {{984:29-33=10.51}}
 }
 
 @available(OSX, unavailable)
@@ -997,12 +1008,14 @@ func castToPotentiallyUnavailableProtocol() {
 
 @available(OSX, introduced: 10.9)
 class SubclassAvailableOn10_9OfClassAvailableOn10_51AlsoAdoptingProtocolAvailableOn10_51 : ClassAvailableOn10_51, ProtocolAvailableOn10_51 { // expected-error {{'ClassAvailableOn10_51' is only available in macOS 10.51 or newer}}
+    // expected-note@-1 {{change the @available attribute of the class on macOS from 10.9 to 10.51}} {{1009:29-33=10.51}}
 }
 
 class SomeGenericClass<T> { }
 
 @available(OSX, introduced: 10.9)
 class SubclassAvailableOn10_9OfSomeGenericClassOfProtocolAvailableOn10_51 : SomeGenericClass<ProtocolAvailableOn10_51> { // expected-error {{'ProtocolAvailableOn10_51' is only available in macOS 10.51 or newer}}
+    // expected-note@-1 {{change the @available attribute of the class on macOS from 10.9 to 10.51}} {{1016:29-33=10.51}}
 }
 
 @available(OSX, unavailable)
@@ -1054,6 +1067,7 @@ extension ClassAvailableOn10_51 {
     let _ = globalFuncAvailableOn10_51()
     let _ = globalFuncAvailableOn10_52() // expected-error {{'globalFuncAvailableOn10_52()' is only available in macOS 10.52 or newer}}
       // expected-note@-1 {{add 'if #available' version check}}
+      // expected-note@-2 {{change the @available attribute of the extension on macOS from 10.51 to 10.52}} {{1063:29-34=10.52}}
   }
 }
 
@@ -1655,6 +1669,7 @@ class ClassWithShortFormAvailableOn10_54 {
 func funcWithShortFormAvailableOn10_9() {
   let _ = ClassWithShortFormAvailableOn10_51() // expected-error {{'ClassWithShortFormAvailableOn10_51' is only available in macOS 10.51 or newer}}
       // expected-note@-1 {{add 'if #available' version check}}
+      // expected-note@-2 {{change the @available attribute of the global function on macOS from 10.9 to 10.51}} {{1668:16-20=10.51}}
 }
 
 @available(OSX 10.51, *)
@@ -1689,6 +1704,7 @@ func funcWithMultipleShortFormAnnotationsForTheSamePlatform() {
 
   let _ = ClassWithShortFormAvailableOn10_54() // expected-error {{'ClassWithShortFormAvailableOn10_54' is only available in macOS 10.54 or newer}}
       // expected-note@-1 {{add 'if #available' version check}}
+      // expected-note@-2 {{change the @available attribute of the global function on macOS from 10.52 to 10.54}} {{1701:16-21=10.54}}
 }
 
 func useShortFormAvailable() {

test/Sema/availability_versions_multi.swift

@@ -34,17 +34,21 @@ func useFromOtherOn99_51() {
   o10_9.extensionMethodOnOtherIntroduced10_9AvailableOn99_51(o99_51)
   _ = o99_51.returns99_52Introduced99_52() // expected-error {{'returns99_52Introduced99_52()' is only available in macOS 99.52 or newer}}
       // expected-note@-1 {{add 'if #available' version check}}
+     // expected-note@-2 {{change the @available attribute of the global function on macOS from 99.51 to 99.52}} {{26:29-34=99.52}}
 
   _ = OtherIntroduced99_52()
       // expected-error@-1 {{'OtherIntroduced99_52' is only available in macOS 99.52 or newer}}
       // expected-note@-2 {{add 'if #available' version check}}
+      // expected-note@-3 {{change the @available attribute of the global function on macOS from 99.51 to 99.52}} {{26:29-34=99.52}}
 
   o99_51.extensionMethodOnOtherIntroduced99_51AvailableOn99_52() // expected-error {{'extensionMethodOnOtherIntroduced99_51AvailableOn99_52()' is only available in macOS 99.52 or newer}}
       // expected-note@-1 {{add 'if #available' version check}}
+      // expected-note@-2 {{change the @available attribute of the global function on macOS from 99.51 to 99.52}} {{26:29-34=99.52}}
 
   _ = OtherIntroduced99_51.NestedIntroduced99_52()
       // expected-error@-1 {{'NestedIntroduced99_52' is only available in macOS 99.52 or newer}}
       // expected-note@-2 {{add 'if #available' version check}}
+      // expected-note@-3 {{change the @available attribute of the global function on macOS from 99.51 to 99.52}} {{26:29-34=99.52}}
 }
 
 @available(OSX, introduced: 99.52)
@@ -55,7 +59,7 @@ func useFromOtherOn99_52() {
   _ = n99_52.returns99_52()
   _ = n99_52.returns99_53() // expected-error {{'returns99_53()' is only available in macOS 99.53 or newer}}
       // expected-note@-1 {{add 'if #available' version check}}
-
+      // expected-note@-2 {{change the @available attribute of the global function on macOS from 99.52 to 99.53}} {{54:29-34=99.53}}
   // This will trigger validation of the global in availability_in_multi_other.swift
   _ = globalFromOtherOn99_52
 }

test/attr/ApplicationMain/attr_main_struct_available_future.swift

@@ -3,6 +3,7 @@
 // REQUIRES: OS=macosx
 
 @main // expected-error {{'main()' is only available in macOS 10.99 or newer}}
+// expected-note @-1 {{change the @available attribute of the struct on macOS from 10.0 to 10.99}}
 @available(OSX 10.0, *)
 struct EntryPoint {
   @available(OSX 10.99, *)

test/attr/attr_availability_osx.swift

@@ -120,6 +120,7 @@ func testMemberAvailability() {
   TestStruct().doAnotherThing() // expected-error {{'doAnotherThing()' is unavailable}}
   TestStruct().doThirdThing() // expected-error {{'doThirdThing()' is unavailable}}
   TestStruct().doFourthThing() // expected-error {{'doFourthThing()' is only available in macOS 10.12 or newer}} expected-note {{'if #available'}}
+  // expected-note @-1 {{change the @available attribute of the global function on macOS from 10.11 to 10.12}}
   TestStruct().doDeprecatedThing() // expected-warning {{'doDeprecatedThing()' is deprecated}}
 }