Merge pull request #29336 from nkcsgexi/diag-refactor-original-defined

Sema: refactor some code to diagnose multiple active platforms for @_originallyDefinedFrom. NFC

Author: nkcsgexi

include/swift/AST/PlatformKind.h

@@ -26,7 +26,7 @@ namespace swift {
 class LangOptions;
 
 /// Available platforms for the availability attribute.
-enum class PlatformKind {
+enum class PlatformKind: uint8_t {
   none,
 #define AVAILABILITY_PLATFORM(X, PrettyName) X,
 #include "swift/AST/PlatformKinds.def"

lib/Sema/TypeCheckAttr.cpp

@@ -2662,42 +2662,40 @@ void AttributeChecker::checkOriginalDefinedInAttrs(Decl *D,
   if (Attrs.empty())
     return;
   auto &Ctx = D->getASTContext();
-  OriginallyDefinedInAttr* theAttr = nullptr;
+  std::map<PlatformKind, SourceLoc> seenPlatforms;
+
   // Attrs are in the reverse order of the source order. We need to visit them
   // in source order to diagnose the later attribute.
   for (auto *Attr: Attrs) {
     if (!Attr->isActivePlatform(Ctx))
       continue;
-    if (theAttr) {
-      // Only one version number is allowed for one platform name.
-      diagnose(theAttr->AtLoc, diag::originally_defined_in_dupe_platform,
-               platformString(Attr->Platform));
+    auto AtLoc = Attr->AtLoc;
+    auto Platform = Attr->Platform;
+    if (!seenPlatforms.insert({Platform, AtLoc}).second) {
+      // We've seen the platform before, emit error to the previous one which
+      // comes later in the source order.
+      diagnose(seenPlatforms[Platform],
+               diag::originally_defined_in_dupe_platform,
+               platformString(Platform));
+      return;
+    }
+    static StringRef AttrName = "_originallyDefinedIn";
+    if (!D->getDeclContext()->isModuleScopeContext()) {
+      diagnose(AtLoc, diag::originally_definedin_topleve_decl, AttrName);
+      return;
+    }
+    auto IntroVer = D->getIntroducedOSVersion(Platform);
+    if (!IntroVer.hasValue()) {
+      diagnose(AtLoc, diag::originally_definedin_need_available,
+               AttrName);
+      return;
+    }
+    if (IntroVer.getValue() >= Attr->MovedVersion) {
+      diagnose(AtLoc,
+               diag::originally_definedin_must_after_available_version,
+               AttrName);
       return;
-    } else {
-      theAttr = Attr;
     }
-  }
-  if (!theAttr)
-    return;
-  assert(theAttr);
-  static StringRef AttrName = "_originallyDefinedIn";
-  auto AtLoc = theAttr->AtLoc;
-  if (!D->getDeclContext()->isModuleScopeContext()) {
-    diagnose(AtLoc, diag::originally_definedin_topleve_decl, AttrName);
-    return;
-  }
-  auto AvailRange = AvailabilityInference::availableRange(D, Ctx);
-  if (!AvailRange.getOSVersion().hasLowerEndpoint()) {
-    diagnose(AtLoc, diag::originally_definedin_need_available,
-             AttrName);
-    return;
-  }
-  auto AvailBegin = AvailRange.getOSVersion().getLowerEndpoint();
-  if (AvailBegin >= theAttr->MovedVersion) {
-    diagnose(AtLoc,
-             diag::originally_definedin_must_after_available_version,
-             AttrName);
-    return;
   }
 }
 

test/Parse/original_defined_in_attr.swift

@@ -19,6 +19,7 @@ class ToplevelClass2 {}
 @_originallyDefinedIn(module: "foo", // expected-error {{expected at least one platform version in @_originallyDefinedIn}}
 class ToplevelClass3 {}
 
+@available(OSX 13.10, *)
 @_originallyDefinedIn(module: "foo", * 13.13) // expected-warning {{* as platform name has no effect}} expected-error {{expected at least one platform version in @_originallyDefinedIn}}
 @_originallyDefinedIn(module: "foo", OSX 13.13, iOS 7.0)
 @_originallyDefinedIn(module: "foo", OSX 13.14, * 7.0) // expected-warning {{* as platform name has no effect}} expected-error {{duplicate version number for platform OSX}}