Test shadowing module qualified macro

Author: ApolloZhu

include/swift/AST/NameLookup.h

@@ -245,6 +245,8 @@ enum class UnqualifiedLookupFlags {
   ExcludeMacroExpansions = 1 << 6,
   /// This lookup should only return macros.
   MacroLookup            = 1 << 7,
+  /// This lookup should only return modules
+  ModuleLookup           = 1 << 8,
 };
 
 using UnqualifiedLookupOptions = OptionSet<UnqualifiedLookupFlags>;

lib/AST/NameLookup.cpp

@@ -113,6 +113,7 @@ void swift::simple_display(llvm::raw_ostream &out,
       {UnqualifiedLookupFlags::IncludeOuterResults, "IncludeOuterResults"},
       {UnqualifiedLookupFlags::TypeLookup, "TypeLookup"},
       {UnqualifiedLookupFlags::MacroLookup, "MacroLookup"},
+      {UnqualifiedLookupFlags::ModuleLookup, "ModuleLookup"},
   };
 
   auto flagsToPrint = llvm::make_filter_range(
@@ -1649,16 +1650,20 @@ SmallVector<MacroDecl *, 1> namelookup::lookupMacros(DeclContext *dc,
   if (moduleName) {
     UnqualifiedLookupDescriptor moduleLookupDesc(
         moduleName, moduleScopeDC, SourceLoc(),
-        UnqualifiedLookupFlags::TypeLookup);
+        UnqualifiedLookupFlags::ModuleLookup);
     auto moduleLookup = evaluateOrDefault(
         ctx.evaluator, UnqualifiedLookupRequest{moduleLookupDesc}, {});
     auto foundTypeDecl = moduleLookup.getSingleTypeResult();
     auto *moduleDecl = dyn_cast_or_null<ModuleDecl>(foundTypeDecl);
     if (!moduleDecl)
       return {};
 
+    auto options = NL_ExcludeMacroExpansions;
+    if (onlyMacros)
+      options |= NL_OnlyMacros;
+
     ModuleQualifiedLookupRequest req{moduleScopeDC, moduleDecl, macroName,
-                                     SourceLoc(), NL_ExcludeMacroExpansions};
+                                     SourceLoc(), options};
     auto lookup = evaluateOrDefault(ctx.evaluator, req, {});
     for (auto *found : lookup)
       addChoiceIfApplicable(found);

lib/AST/UnqualifiedLookup.cpp

@@ -281,6 +281,12 @@ void UnqualifiedLookupFactory::performUnqualifiedLookup() {
                                   "performUnqualifiedLookup",
                                   DC->getParentSourceFile());
 
+  if (options.contains(UnqualifiedLookupFlags::ModuleLookup)) {
+    lookForAModuleWithTheGivenName(DC->getModuleScopeContext());
+    recordCompletionOfAScope();
+    return;
+  }
+
   if (Loc.isValid() && DC->getParentSourceFile()) {
     // Operator lookup is always global, for the time being.
     if (!Name.isOperator())

test/Macros/Inputs/macro_library.swift

@@ -42,3 +42,14 @@ public macro AddClassReferencingSelf() = #externalMacro(module: "MacroDefinition
 
 @attached(peer, names: named(value))
 public macro declareVarValuePeer() = #externalMacro(module: "MacroDefinition", type: "VarValueMacro")
+
+@propertyWrapper
+public struct declareVarValuePeerShadowed {
+  public var wrappedValue: Int
+  public init(wrappedValue: Int) {
+    self.wrappedValue = wrappedValue
+  }
+}
+
+@attached(peer, names: named(value))
+public macro declareVarValuePeerShadowed() = #externalMacro(module: "MacroDefinition", type: "VarValueMacro")

test/Macros/macro_shadowing.swift

@@ -7,14 +7,29 @@
 
 // Build library that declares macros
 // RUN: %target-swift-frontend -swift-version 5 -emit-module -o %t/freestanding_macro_library.swiftmodule %S/Inputs/freestanding_macro_library.swift -module-name freestanding_macro_library -load-plugin-library %t/%target-library-name(MacroDefinition)
-
+// RUN: %target-swift-frontend -swift-version 5 -emit-module -o %t/macro_library.swiftmodule %S/Inputs/macro_library.swift -module-name macro_library -load-plugin-library %t/%target-library-name(MacroDefinition) -enable-experimental-feature ExtensionMacros 
 // 
 // RUN: %target-typecheck-verify-swift -swift-version 5 -load-plugin-library %t/%target-library-name(MacroDefinition) -module-name MacroUser -I %t
 
 import freestanding_macro_library
+import macro_library
 
 struct stringify<T> { }
 
 func testStringify(a: Int, b: Int) {
   _ = #stringify(a + b)
 }
+
+enum macro_library {
+  @propertyWrapper
+  struct declareVarValuePeerShadowed {
+    var wrappedValue: Int
+  }
+}
+
+struct TestShadowedQualified {
+  @macro_library.declareVarValuePeerShadowed
+  var shouldFindMacro: Int = 3
+}
+
+_ = TestShadowedQualified().value