Diagnose for invalid decl nesting + namespace lookup fixes. (#3397)

* Diagnose for invalid decl nesting.

* Fix.

* Fix.

* Fix.

* Fix `namespace` lookup and `using` resolution.

* fix project files.

* revert project files.

* Enhance namespace syntax, docs.

* Fixes.

---------

Co-authored-by: Yong He <yhe@nvidia.com>

1 files changed, 71 insertions, 0 deletions

diff --git a/source/slang/slang-syntax.cpp b/source/slang/slang-syntax.cpp
index 6350a7e4d..ab0dfcd74 100644
--- a/source/slang/slang-syntax.cpp
+++ b/source/slang/slang-syntax.cpp
@@ -25,6 +25,77 @@ void printDiagnosticArg(StringBuilder& sb, DeclRefBase* declRefBase)
     printDiagnosticArg(sb, declRefBase->getDecl());
 }
 
+void printDiagnosticArg(StringBuilder& sb, ASTNodeType nodeType)
+{
+    // TODO: this can be generated.
+
+    switch (nodeType)
+    {
+        case ASTNodeType::Decl: sb << "Decl"; break;
+        case ASTNodeType::UnresolvedDecl: sb << "UnresolvedDecl"; break;
+        case ASTNodeType::ContainerDecl: sb << "ContainerDecl"; break;
+        case ASTNodeType::AggTypeDeclBase: sb << "AggTypeDeclBase"; break;
+        case ASTNodeType::ExtensionDecl: sb << "extension"; break;
+        case ASTNodeType::AggTypeDecl: sb << "AggTypeDecl"; break;
+        case ASTNodeType::StructDecl: sb << "struct"; break;
+        case ASTNodeType::ClassDecl: sb << "class"; break;
+        case ASTNodeType::GLSLInterfaceBlockDecl: sb << "GLSL interface block"; break;
+        case ASTNodeType::EnumDecl: sb << "enum"; break;
+        case ASTNodeType::ThisTypeDecl: sb << "This"; break;
+        case ASTNodeType::InterfaceDecl: sb << "interface"; break;
+        case ASTNodeType::AssocTypeDecl: sb << "associatedtype"; break;
+        case ASTNodeType::GlobalGenericParamDecl: sb << "global generic param"; break;
+        case ASTNodeType::ScopeDecl: sb << "scope"; break;
+        case ASTNodeType::CallableDecl: sb << "CallableDecl"; break;
+        case ASTNodeType::FunctionDeclBase: sb << "FunctionDeclBase"; break;
+        case ASTNodeType::ConstructorDecl: sb << "__init"; break;
+        case ASTNodeType::AccessorDecl: sb << "accessor"; break;
+        case ASTNodeType::GetterDecl: sb << "getter"; break;
+        case ASTNodeType::SetterDecl: sb << "setter"; break;
+        case ASTNodeType::RefAccessorDecl: sb << "ref accessor"; break;
+        case ASTNodeType::FuncDecl: sb << "function"; break;
+        case ASTNodeType::DerivativeRequirementDecl: sb << "DerivativeRequirementDecl"; break;
+        case ASTNodeType::ForwardDerivativeRequirementDecl: sb << "ForwardDerivativeRequirementDecl"; break;
+        case ASTNodeType::BackwardDerivativeRequirementDecl: sb << "BackwardDerivativeRequirementDecl"; break;
+        case ASTNodeType::DerivativeRequirementReferenceDecl: sb << "DerivativeRequirementReferenceDecl"; break;
+        case ASTNodeType::SubscriptDecl: sb << "__subscript"; break;
+        case ASTNodeType::PropertyDecl: sb << "property"; break;
+        case ASTNodeType::NamespaceDeclBase: sb << "NamespaceDeclBase"; break;
+        case ASTNodeType::NamespaceDecl: sb << "namespace"; break;
+        case ASTNodeType::ModuleDecl: sb << "module"; break;
+        case ASTNodeType::FileDecl: sb << "included file"; break;
+        case ASTNodeType::GenericDecl: sb << "generic"; break;
+        case ASTNodeType::AttributeDecl: sb << "attribute"; break;
+        case ASTNodeType::VarDeclBase: sb << "variable definition"; break;
+        case ASTNodeType::VarDecl: sb << "variable definition"; break;
+        case ASTNodeType::LetDecl: sb << "immutable value definition"; break;
+        case ASTNodeType::GlobalGenericValueParamDecl: sb << "GlobalGenericValueParamDecl"; break;
+        case ASTNodeType::ParamDecl: sb << "parameter"; break;
+        case ASTNodeType::ModernParamDecl: sb << "parameter"; break;
+        case ASTNodeType::GenericValueParamDecl: sb << "GenericValueParamDecl"; break;
+        case ASTNodeType::EnumCaseDecl: sb << "enum case"; break;
+        case ASTNodeType::TypeConstraintDecl: sb << "TypeConstraintDecl"; break;
+        case ASTNodeType::ThisTypeConstraintDecl: sb << "ThisTypeConstraintDecl"; break;
+        case ASTNodeType::InheritanceDecl: sb << "InheritanceDecl"; break;
+        case ASTNodeType::GenericTypeConstraintDecl: sb << "GenericTypeConstraintDecl"; break;
+        case ASTNodeType::SimpleTypeDecl: sb << "SimpleTypeDecl"; break;
+        case ASTNodeType::TypeDefDecl: sb << "typedef"; break;
+        case ASTNodeType::TypeAliasDecl: sb << "typealias"; break;
+        case ASTNodeType::GenericTypeParamDecl: sb << "GenericTypeParamDecl"; break;
+        case ASTNodeType::UsingDecl: sb << "using"; break;
+        case ASTNodeType::FileReferenceDeclBase: sb << "FileReferenceDeclBase"; break;
+        case ASTNodeType::ImportDecl: sb << "import"; break;
+        case ASTNodeType::IncludeDeclBase: sb << "IncludeDeclBase"; break;
+        case ASTNodeType::IncludeDecl: sb << "__include"; break;
+        case ASTNodeType::ImplementingDecl: sb << "implementing"; break;
+        case ASTNodeType::ModuleDeclarationDecl: sb << "module"; break;
+        case ASTNodeType::EmptyDecl: sb << "empty"; break;
+        case ASTNodeType::SyntaxDecl: sb << "syntax"; break;
+        case ASTNodeType::DeclGroup: sb << "decl-group"; break;
+        default: sb << "decl"; break;
+    }
+}
+
 void printDiagnosticArg(StringBuilder& sb, Type* type)
 {
     if (!type)