Ensure that top-level macro expansions are in the JSON AST dump.

Author: allevato

lib/AST/ASTDumper.cpp

@@ -1905,6 +1905,21 @@ namespace {
       printSourceRange(D->getSourceRange(), &D->getASTContext());
       printFlag(D->TrailingSemiLoc.isValid(), "trailing_semi",
                 DeclModifierColor);
+
+      if (Writer.isParsable()) {
+        // Print just the USRs of any auxiliary decls associated with this decl,
+        // which lets us relate macro expansions back to their originating decl
+        // if desired.
+        std::vector<std::string> auxiliaryUSRs;
+        D->visitAuxiliaryDecls([&auxiliaryUSRs](Decl *auxDecl) {
+          if (auto usr = declUSR(auxDecl); !usr.empty()) {
+            auxiliaryUSRs.push_back(usr);
+          }
+        });
+        printStringListField(
+            auxiliaryUSRs, [&](auto usr) { return usr; },
+            Label::always("auxiliary_decl_usrs"));
+      }
     }
 
     void printInherited(InheritedTypes Inherited) {
@@ -2274,31 +2289,50 @@ namespace {
         }, Label::always("compiler_version"));
       }
 
-      std::optional<std::vector<ASTNode>> items;
+      std::vector<ASTNode> items;
+      bool shouldPrintImplicit;
+
       switch (MemberLoading) {
       case ASTDumpMemberLoading::None:
-        items = SF.getCachedTopLevelItems();
+        shouldPrintImplicit = false;
+        if (auto cached = SF.getCachedTopLevelItems()) {
+          items = *cached;
+        }
         break;
       case ASTDumpMemberLoading::Parsed:
-      case ASTDumpMemberLoading::TypeChecked:
+        shouldPrintImplicit = false;
         items = SF.getTopLevelItems();
         break;
-      }
-      if (items) {
-        printList(*items, [&](ASTNode item, Label label) {
-          if (item.isImplicit())
-            return;
+      case ASTDumpMemberLoading::TypeChecked:
+        shouldPrintImplicit = true;
+        for (ASTNode item : SF.getTopLevelItems()) {
+          items.push_back(item);
 
+          // If the item is a decl, also collect any auxiliary decls associated
+          // with it so that we get macro expansions.
           if (auto decl = item.dyn_cast<Decl *>()) {
-            printRec(decl, label);
-          } else if (auto stmt = item.dyn_cast<Stmt *>()) {
-            printRec(stmt, &SF.getASTContext(), label);
-          } else {
-            auto expr = item.get<Expr *>();
-            printRec(expr, label);
+            decl->visitAuxiliaryDecls(
+                [&items](Decl *auxDecl) { items.push_back(auxDecl); });
           }
-        }, Label::optional("items"));
+        }
+        break;
       }
+      printList(
+          items,
+          [&](ASTNode item, Label label) {
+            if (!shouldPrintImplicit && item.isImplicit())
+              return;
+
+            if (auto decl = item.dyn_cast<Decl *>()) {
+              printRec(decl, label);
+            } else if (auto stmt = item.dyn_cast<Stmt *>()) {
+              printRec(stmt, &SF.getASTContext(), label);
+            } else {
+              auto expr = item.get<Expr *>();
+              printRec(expr, label);
+            }
+          },
+          Label::optional("items"));
       printFoot();
     }
 

test/Frontend/Inputs/json_ast_macro_definitions.swift

@@ -17,3 +17,32 @@ struct MemberInjectingMacro: MemberMacro {
     return [member]
   }
 }
+
+struct PeerInjectingMacro: PeerMacro {
+  public static func expansion(
+    of node: AttributeSyntax,
+    providingPeersOf decl: some DeclSyntaxProtocol,
+    in context: some MacroExpansionContext
+  ) throws -> [DeclSyntax] {
+    let peer: DeclSyntax =
+      """
+      struct FixedNamePeer {}
+      """
+
+    return [peer]
+  }
+}
+
+struct FreestandingInjectingMacro: DeclarationMacro {
+  public static func expansion(
+    of node: some FreestandingMacroExpansionSyntax,
+    in context: some MacroExpansionContext
+  ) throws -> [DeclSyntax] {
+    let peer: DeclSyntax =
+      """
+      struct FixedNameFreestander {}
+      """
+
+    return [peer]
+  }
+}

test/Frontend/Inputs/json_ast_macro_library.swift

@@ -1,2 +1,8 @@
 @attached(member, names: named(_macroInjectedMember))
 public macro InjectMember() = #externalMacro(module: "MacroDefinition", type: "MemberInjectingMacro")
+
+@attached(peer, names: named(FixedNamePeer))
+public macro InjectPeer() = #externalMacro(module: "MacroDefinition", type: "PeerInjectingMacro")
+
+@freestanding(declaration, names: named(FixedNameFreestander))
+public macro injectFreestanding() = #externalMacro(module: "MacroDefinition", type: "FreestandingInjectingMacro")

test/Frontend/ast-dump-json-macros.swift

@@ -6,15 +6,42 @@
 // RUN: %empty-directory(%t)
 // RUN: %host-build-swift -swift-version 5 -emit-library -o %t/%target-library-name(MacroDefinition) -module-name=MacroDefinition %S/Inputs/json_ast_macro_definitions.swift -g -no-toolchain-stdlib-rpath
 // RUN: %target-swift-frontend -swift-version 5 -emit-module -o %t/json_ast_macro_library.swiftmodule %S/Inputs/json_ast_macro_library.swift -module-name json_ast_macro_library -load-plugin-library %t/%target-library-name(MacroDefinition)
-// RUN: %target-swift-frontend -target %target-swift-5.9-abi-triple -I %t -load-plugin-library %t/%target-library-name(MacroDefinition) -parse-as-library -dump-ast -dump-ast-format json %s -module-name main -o - | %FileCheck %s
+// RUN: %target-swift-frontend -target %target-swift-5.9-abi-triple -I %t -load-plugin-library %t/%target-library-name(MacroDefinition) -parse-as-library -dump-ast -dump-ast-format json %s -module-name main -o -
+// | %FileCheck %s
 
 import json_ast_macro_library
 
 @InjectMember
 struct X {
     var y: Int
 }
-
 // CHECK:      "_kind":"pattern_binding_decl"
 // CHECK-SAME: "buffer_id":"@__swiftmacro_4main1X12InjectMemberfMm_.swift"
 // CHECK-SAME: "name":"_macroInjectedMember"
+
+struct Z {
+    #injectFreestanding
+}
+// NOTE: For freestanding members (as opposed to top-level), we get the expanded
+// decl before we see the MacroExpansionDecl.
+// CHECK-SAME: "_kind":"struct_decl",
+// CHECK-SAME: "usr":"s:4main1ZV20FixedNameFreestanderV",
+// CHECK-SAME: "buffer_id":"@__swiftmacro_4main0033astdumpjsonmacrosswift_GwAFheaeGafMX{{\d+}}_{{\d+}}_33_{{[0-9A-F]+}}Ll18injectFreestandingfMf_.swift"
+// CHECK-SAME: "_kind": "macro_expansion_decl",
+// CHECK-SAME: "auxiliary_decl_usrs":["s:4main1ZV20FixedNameFreestanderV"]
+
+@InjectPeer
+struct ThisWillBePeered {}
+// CHECK-SAME: "_kind":"struct_decl",
+// CHECK-SAME: "usr":"s:4main16ThisWillBePeeredV",
+// CHECK-SAME: "auxiliary_decl_usrs":["s:4main13FixedNamePeerV"],
+// CHECK-SAME: "_kind":"struct_decl",
+// CHECK-SAME: "usr":"s:4main13FixedNamePeerV",
+// CHECK-SAME: "buffer_id":"@__swiftmacro_4main16ThisWillBePeered10InjectPeerfMp_.swift"
+
+#injectFreestanding
+// CHECK-SAME: "_kind":"macro_expansion_decl",
+// CHECK-SAME: "auxiliary_decl_usrs":["s:4main20FixedNameFreestanderV"],
+// CHECK-SAME: "_kind":"struct_decl",
+// CHECK-SAME: "usr":"s:4main20FixedNameFreestanderV",
+// CHECK-SAME: "buffer_id":"@__swiftmacro_4main0033astdumpjsonmacrosswift_GwAFheaeGafMX{{\d+}}_{{\d+}}_33_{{[0-9A-F]+}}Ll18injectFreestandingfMf_.swift"