[clang] [Clang] Unify interface for accessing template arguments as written for class/variable template specializations (PR #81642)

[Krystian Stasiowski via cfe-commits]

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@@ -1985,44 +1986,45 @@ class ClassTemplateSpecializationDecl
     SpecializedTemplate = TemplDecl;
   }
 
-  /// Sets the type of this specialization as it was written by
-  /// the user. This will be a class template specialization type.
-  void setTypeAsWritten(TypeSourceInfo *T) {
-    if (!ExplicitInfo)
-      ExplicitInfo = new (getASTContext()) ExplicitSpecializationInfo;
-    ExplicitInfo->TypeAsWritten = T;
-  }
-
-  /// Gets the type of this specialization as it was written by
-  /// the user, if it was so written.
-  TypeSourceInfo *getTypeAsWritten() const {
-    return ExplicitInfo ? ExplicitInfo->TypeAsWritten : nullptr;
+  const ASTTemplateArgumentListInfo *getTemplateArgsAsWritten() const {
+    if (auto *Info = ExplicitInfo.dyn_cast<ExplicitInstantiationInfo *>())
+      return Info->TemplateArgsAsWritten;
+    return ExplicitInfo.get<const ASTTemplateArgumentListInfo *>();
   }
 
   /// Gets the location of the extern keyword, if present.
   SourceLocation getExternLoc() const {
-    return ExplicitInfo ? ExplicitInfo->ExternLoc : SourceLocation();
+    if (auto *Info = ExplicitInfo.dyn_cast<ExplicitInstantiationInfo *>())
+      return Info->ExternLoc;
+    return SourceLocation();
   }
 
-  /// Sets the location of the extern keyword.
-  void setExternLoc(SourceLocation Loc) {
-    if (!ExplicitInfo)
-      ExplicitInfo = new (getASTContext()) ExplicitSpecializationInfo;
-    ExplicitInfo->ExternLoc = Loc;
+  /// Gets the location of the template keyword, if present.
+  SourceLocation getTemplateKeywordLoc() const {
+    if (auto *Info = ExplicitInfo.dyn_cast<ExplicitInstantiationInfo *>())
+      return Info->TemplateKeywordLoc;
+    return SourceLocation();
   }
 
-  /// Sets the location of the template keyword.
-  void setTemplateKeywordLoc(SourceLocation Loc) {
-    if (!ExplicitInfo)
-      ExplicitInfo = new (getASTContext()) ExplicitSpecializationInfo;
-    ExplicitInfo->TemplateKeywordLoc = Loc;
+  void
+  setTemplateArgsAsWritten(const ASTTemplateArgumentListInfo *ArgsWritten) {
+    if (auto *Info = ExplicitInfo.dyn_cast<ExplicitInstantiationInfo *>())
+      Info->TemplateArgsAsWritten = ArgsWritten;
+    else
+      ExplicitInfo = ArgsWritten;
   }
 
-  /// Gets the location of the template keyword, if present.
-  SourceLocation getTemplateKeywordLoc() const {
-    return ExplicitInfo ? ExplicitInfo->TemplateKeywordLoc : SourceLocation();
+  void setTemplateArgsAsWritten(const TemplateArgumentListInfo &ArgsInfo) {
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sdkrystian wrote:

Sure

https://github.com/llvm/llvm-project/pull/81642