AST: Remove 'OS' from AvailabilityContext member names.

An `AvailabilityContext` represents an abstract version range in which
something is available. In the future, these version ranges may not necessarily
always correspond to operating system version ranges.

NFC.

Author: tshortli

include/swift/AST/Availability.h

@@ -216,8 +216,7 @@ class UnavailabilityReason {
   bool requiresDeploymentTargetOrEarlier(ASTContext &Ctx) const;
 };
 
-/// Represents everything that a particular chunk of code may assume about its
-/// runtime environment.
+/// Represents a version range in which something is available.
 ///
 /// The AvailabilityContext structure forms a [lattice][], which allows it to
 /// have meaningful union and intersection operations ("join" and "meet"),
@@ -229,11 +228,10 @@ class UnavailabilityReason {
 /// NOTE: Generally you should use the utilities on \c AvailabilityInference
 /// to create an \c AvailabilityContext, rather than creating one directly.
 class AvailabilityContext {
-  VersionRange OSVersion;
+  VersionRange Range;
 
 public:
-  /// Creates a context that requires certain versions of the target OS.
-  explicit AvailabilityContext(VersionRange OSVersion) : OSVersion(OSVersion) {}
+  explicit AvailabilityContext(VersionRange Range) : Range(Range) {}
 
   /// Creates a context that imposes the constraints of the ASTContext's
   /// deployment target.
@@ -261,21 +259,21 @@ class AvailabilityContext {
     return AvailabilityContext(VersionRange::empty());
   }
 
-  /// Returns the range of possible OS versions required by this context.
-  VersionRange getOSVersion() const { return OSVersion; }
+  /// Returns the range of possible versions required by this context.
+  VersionRange getVersionRange() const { return Range; }
 
   /// Returns true if \p other makes stronger guarantees than this context.
   ///
   /// That is, `a.isContainedIn(b)` implies `a.union(b) == b`.
   bool isContainedIn(const AvailabilityContext &other) const {
-    return OSVersion.isContainedIn(other.OSVersion);
+    return Range.isContainedIn(other.Range);
   }
 
   /// Returns true if \p other is a strict subset of this context.
   ///
   /// That is, `a.isSupersetOf(b)` implies `a != b` and `a.union(b) == a`.
   bool isSupersetOf(const AvailabilityContext &other) const {
-    return OSVersion.isSupersetOf(other.OSVersion);
+    return Range.isSupersetOf(other.Range);
   }
 
   /// Returns true if this context has constraints that make it impossible to
@@ -284,13 +282,13 @@ class AvailabilityContext {
   /// For example, the else branch of a `#available` check for iOS 8.0 when the
   /// containing function already requires iOS 9.
   bool isKnownUnreachable() const {
-    return OSVersion.isEmpty();
+    return Range.isEmpty();
   }
 
   /// Returns true if there are no constraints on this context; that is,
   /// nothing can be assumed.
   bool isAlwaysAvailable() const {
-    return OSVersion.isAll();
+    return Range.isAll();
   }
 
   /// Produces an under-approximation of the intersection of the two
@@ -303,7 +301,7 @@ class AvailabilityContext {
   /// As an example, this is used when figuring out the required availability
   /// for a type that references multiple nominal decls.
   void intersectWith(const AvailabilityContext &other) {
-    OSVersion.intersectWith(other.getOSVersion());
+    Range.intersectWith(other.Range);
   }
 
   /// Produces an over-approximation of the intersection of the two
@@ -314,7 +312,7 @@ class AvailabilityContext {
   ///
   /// As an example, this is used for the true branch of `#available`.
   void constrainWith(const AvailabilityContext &other) {
-    OSVersion.constrainWith(other.getOSVersion());
+    Range.constrainWith(other.Range);
   }
 
   /// Produces an over-approximation of the union of two availability contexts.
@@ -326,12 +324,12 @@ class AvailabilityContext {
   /// As an example, this is used for the else branch of a conditional with
   /// multiple `#available` checks.
   void unionWith(const AvailabilityContext &other) {
-    OSVersion.unionWith(other.getOSVersion());
+    Range.unionWith(other.Range);
   }
 
   /// Returns a representation of this range as a string for debugging purposes.
   std::string getAsString() const {
-    return "AvailabilityContext(" + OSVersion.getAsString() + ")";
+    return "AvailabilityContext(" + Range.getAsString() + ")";
   }
 };
 

lib/AST/Availability.cpp

@@ -521,7 +521,7 @@ bool UnavailabilityReason::requiresDeploymentTargetOrEarlier(
     ASTContext &Ctx) const {
   return RequiredDeploymentRange.getLowerEndpoint() <=
          AvailabilityContext::forDeploymentTarget(Ctx)
-             .getOSVersion()
+             .getVersionRange()
              .getLowerEndpoint();
 }
 

lib/AST/TypeRefinementContext.cpp

@@ -365,7 +365,7 @@ void TypeRefinementContext::print(raw_ostream &OS, SourceManager &SrcMgr,
   OS.indent(Indent);
   OS << "(" << getReasonName(getReason());
 
-  OS << " versions=" << AvailabilityInfo.getOSVersion().getAsString();
+  OS << " versions=" << AvailabilityInfo.getVersionRange().getAsString();
 
   if (getReason() == Reason::Decl || getReason() == Reason::DeclImplicit) {
     Decl *D = Node.getAsDecl();
@@ -391,7 +391,7 @@ void TypeRefinementContext::print(raw_ostream &OS, SourceManager &SrcMgr,
 
   if (!ExplicitAvailabilityInfo.isAlwaysAvailable())
     OS << " explicit_versions="
-       << ExplicitAvailabilityInfo.getOSVersion().getAsString();
+       << ExplicitAvailabilityInfo.getVersionRange().getAsString();
 
   for (TypeRefinementContext *Child : Children) {
     OS << '\n';

lib/ClangImporter/ImportDecl.cpp

@@ -541,7 +541,7 @@ static void applyAvailableAttribute(Decl *decl, AvailabilityContext &info,
                                       /*Message=*/StringRef(),
                                       /*Rename=*/StringRef(),
                                       /*RenameDecl=*/nullptr,
-                                      info.getOSVersion().getLowerEndpoint(),
+                                      info.getVersionRange().getLowerEndpoint(),
                                       /*IntroducedRange*/SourceRange(),
                                       /*Deprecated=*/noVersion,
                                       /*DeprecatedRange*/SourceRange(),
@@ -2800,11 +2800,11 @@ namespace {
 
         auto ctx = Impl.SwiftContext.getSwift58Availability();
         if (!ctx.isAlwaysAvailable()) {
-          assert(ctx.getOSVersion().hasLowerEndpoint());
+          assert(ctx.getVersionRange().hasLowerEndpoint());
           auto AvAttr = new (Impl.SwiftContext) AvailableAttr(
               SourceLoc(), SourceRange(),
               targetPlatform(Impl.SwiftContext.LangOpts), "", "",
-              /*RenameDecl=*/nullptr, ctx.getOSVersion().getLowerEndpoint(),
+              /*RenameDecl=*/nullptr, ctx.getVersionRange().getLowerEndpoint(),
               /*IntroducedRange=*/SourceRange(), {},
               /*DeprecatedRange=*/SourceRange(), {},
               /*ObsoletedRange=*/SourceRange(),
@@ -6615,7 +6615,7 @@ bool SwiftDeclConverter::existingConstructorIsWorse(
     if (!introduced.empty())
       return false;
   } else {
-    VersionRange existingIntroduced = existingAvailability.getOSVersion();
+    VersionRange existingIntroduced = existingAvailability.getVersionRange();
     if (introduced != existingIntroduced.getLowerEndpoint()) {
       return introduced < existingIntroduced.getLowerEndpoint();
     }

lib/IRGen/GenMeta.cpp

@@ -5116,8 +5116,8 @@ diagnoseUnsupportedObjCImplLayout(IRGenModule &IGM, ClassDecl *classDecl,
             field.getVarDecl(),
             diag::attr_objc_implementation_resilient_property_deployment_target,
             prettyPlatformString(targetPlatform(ctx.LangOpts)),
-            currentAvailability.getOSVersion().getLowerEndpoint(),
-            requiredAvailability.getOSVersion().getLowerEndpoint());
+            currentAvailability.getVersionRange().getLowerEndpoint(),
+            requiredAvailability.getVersionRange().getLowerEndpoint());
       else
         diags.diagnose(
             field.getVarDecl(),

lib/SIL/IR/SILPrinter.cpp

@@ -3438,7 +3438,7 @@ void SILFunction::print(SILPrintContext &PrintCtx) const {
     OS << "[weak_imported] ";
   auto availability = getAvailabilityForLinkage();
   if (!availability.isAlwaysAvailable()) {
-    auto version = availability.getOSVersion().getLowerEndpoint();
+    auto version = availability.getVersionRange().getLowerEndpoint();
     OS << "[available " << version.getAsString() << "] ";
   }
 
@@ -4409,8 +4409,8 @@ void SILSpecializeAttr::print(llvm::raw_ostream &OS) const {
   if (targetFunction) {
     OS << "target: \"" << targetFunction->getName() << "\", ";
   }
- if (!availability.isAlwaysAvailable()) {
-    auto version = availability.getOSVersion().getLowerEndpoint();
+  if (!availability.isAlwaysAvailable()) {
+    auto version = availability.getVersionRange().getLowerEndpoint();
     OS << "available: " << version.getAsString() << ", ";
   }
   if (!requirements.empty()) {

lib/Sema/TypeCheckAttr.cpp

@@ -1681,10 +1681,11 @@ visitObjCImplementationAttr(ObjCImplementationAttr *attr) {
     // supported.
     auto deploymentAvailability = AvailabilityContext::forDeploymentTarget(Ctx);
     if (!deploymentAvailability.isContainedIn(Ctx.getSwift50Availability())) {
-      auto diag = diagnose(attr->getLocation(),
-               diag::attr_objc_implementation_raise_minimum_deployment_target,
-               prettyPlatformString(targetPlatform(Ctx.LangOpts)),
-               Ctx.getSwift50Availability().getOSVersion().getLowerEndpoint());
+      auto diag = diagnose(
+          attr->getLocation(),
+          diag::attr_objc_implementation_raise_minimum_deployment_target,
+          prettyPlatformString(targetPlatform(Ctx.LangOpts)),
+          Ctx.getSwift50Availability().getVersionRange().getLowerEndpoint());
       if (attr->isEarlyAdopter()) {
         diag.wrapIn(diag::wrap_objc_implementation_will_become_error);
       }
@@ -2209,11 +2210,11 @@ void AttributeChecker::visitAvailableAttr(AvailableAttr *attr) {
                    diag::availability_implicit_decl_here,
                    D->getDescriptiveKind(),
                    prettyPlatformString(targetPlatform(Ctx.LangOpts)),
-                   AttrRange.getOSVersion().getLowerEndpoint());
+                   AttrRange.getVersionRange().getLowerEndpoint());
         diagnose(enclosingDecl->getLoc(),
                  diag::availability_decl_more_than_enclosing_here,
                  prettyPlatformString(targetPlatform(Ctx.LangOpts)),
-                 EnclosingAnnotatedRange->getOSVersion().getLowerEndpoint());
+                 EnclosingAnnotatedRange->getVersionRange().getLowerEndpoint());
       }
     }
   }

lib/Sema/TypeCheckAvailability.cpp

@@ -1119,7 +1119,7 @@ class TypeRefinementContextBuilder : private ASTWalker {
       }
 
       AvailabilityContext NewConstraint = contextForSpec(Spec, false);
-      Query->setAvailableRange(contextForSpec(Spec, true).getOSVersion());
+      Query->setAvailableRange(contextForSpec(Spec, true).getVersionRange());
 
       // When compiling zippered for macCatalyst, we need to collect both
       // a macOS version (the target version) and an iOS/macCatalyst version
@@ -1130,7 +1130,7 @@ class TypeRefinementContextBuilder : private ASTWalker {
         AvailabilitySpec *VariantSpec =
             bestActiveSpecForQuery(Query, /*ForTargetVariant*/ true);
         VersionRange VariantRange =
-            contextForSpec(VariantSpec, true).getOSVersion();
+            contextForSpec(VariantSpec, true).getVersionRange();
         Query->setVariantAvailableRange(VariantRange);
       }
 
@@ -1474,7 +1474,7 @@ TypeChecker::checkDeclarationAvailability(const Decl *D,
     AvailabilityContext safeRangeUnderApprox{
         AvailabilityInference::availableRange(D, Context)};
 
-    VersionRange version = safeRangeUnderApprox.getOSVersion();
+    VersionRange version = safeRangeUnderApprox.getVersionRange();
     return UnavailabilityReason::requiresVersionRange(version);
   }
 
@@ -1921,7 +1921,8 @@ static bool fixAvailabilityByNarrowingNearbyVersionCheck(
                                                            ReferenceDC, &TRC);
   if (!TRC)
     return false;
-  VersionRange RunningRange = TRC->getExplicitAvailabilityInfo().getOSVersion();
+  VersionRange RunningRange =
+      TRC->getExplicitAvailabilityInfo().getVersionRange();
   if (RunningRange.hasLowerEndpoint() &&
       RequiredRange.hasLowerEndpoint() &&
       TRC->getReason() != TypeRefinementContext::Reason::Root &&
@@ -2100,9 +2101,9 @@ bool TypeChecker::checkAvailability(SourceRange ReferenceRange,
     TypeChecker::overApproximateAvailabilityAtLocation(
       ReferenceRange.Start, ReferenceDC);
   if (!runningOS.isContainedIn(Availability)) {
-    diagnosePotentialUnavailability(
-      ReferenceRange, Diag, ReferenceDC,
-      UnavailabilityReason::requiresVersionRange(Availability.getOSVersion()));
+    diagnosePotentialUnavailability(ReferenceRange, Diag, ReferenceDC,
+                                    UnavailabilityReason::requiresVersionRange(
+                                        Availability.getVersionRange()));
     return true;
   }
 
@@ -4634,7 +4635,7 @@ static bool declNeedsExplicitAvailability(const Decl *decl) {
 
   // Warn on decls without an introduction version.
   auto safeRangeUnderApprox = AvailabilityInference::availableRange(decl, ctx);
-  return !safeRangeUnderApprox.getOSVersion().hasLowerEndpoint();
+  return !safeRangeUnderApprox.getVersionRange().hasLowerEndpoint();
 }
 
 void swift::checkExplicitAvailability(Decl *decl) {

lib/Sema/TypeCheckDeclObjC.cpp

@@ -521,11 +521,11 @@ static bool checkObjCClassStubAvailability(ASTContext &ctx, const Decl *decl) {
   auto minRange = getMinOSVersionForClassStubs(ctx.LangOpts.Target);
 
   auto targetRange = AvailabilityContext::forDeploymentTarget(ctx);
-  if (targetRange.getOSVersion().isContainedIn(minRange))
+  if (targetRange.getVersionRange().isContainedIn(minRange))
     return true;
 
   auto declRange = AvailabilityInference::availableRange(decl, ctx);
-  return declRange.getOSVersion().isContainedIn(minRange);
+  return declRange.getVersionRange().isContainedIn(minRange);
 }
 
 static const ClassDecl *getResilientAncestor(ModuleDecl *mod,

lib/Sema/TypeCheckProtocol.cpp

@@ -4316,7 +4316,7 @@ ConformanceChecker::resolveWitnessViaLookup(ValueDecl *requirement) {
               diagLoc, diag::availability_protocol_requires_version,
               conformance->getProtocol(), witness,
               prettyPlatformString(targetPlatform(ctx.LangOpts)),
-              check.RequiredAvailability.getOSVersion().getLowerEndpoint());
+              check.RequiredAvailability.getVersionRange().getLowerEndpoint());
           emitDeclaredHereIfNeeded(diags, diagLoc, witness);
           diags.diagnose(requirement,
                          diag::availability_protocol_requirement_here);
@@ -4821,7 +4821,7 @@ static bool diagnoseTypeWitnessAvailability(
   if (!TypeChecker::isAvailabilitySafeForConformance(conformance->getProtocol(),
                                                      assocType, witness, dc,
                                                      requiredAvailability)) {
-    auto requiredRange = requiredAvailability.getOSVersion();
+    auto requiredRange = requiredAvailability.getVersionRange();
     ctx.addDelayedConformanceDiag(
         conformance, shouldError,
         [witness, requiredRange](NormalProtocolConformance *conformance) {