Add refactoring support for accessor macros

Author: DougGregor

include/swift/AST/TypeCheckRequests.h

@@ -3825,6 +3825,26 @@ class ExpandMacroExpansionDeclRequest
   bool isCached() const { return true; }
 };
 
+/// Expand all accessor macros attached to the given declaration.
+///
+/// Produces the set of macro expansion buffer IDs.
+class ExpandAccessorMacros
+    : public SimpleRequest<ExpandAccessorMacros,
+                           ArrayRef<unsigned>(AbstractStorageDecl *),
+                           RequestFlags::Cached> {
+public:
+  using SimpleRequest::SimpleRequest;
+
+private:
+  friend SimpleRequest;
+
+  ArrayRef<unsigned> evaluate(
+      Evaluator &evaluator, AbstractStorageDecl *storage) const;
+
+public:
+  bool isCached() const { return true; }
+};
+
 /// Expand all member attribute macros attached to the given
 /// declaration.
 ///

include/swift/AST/TypeCheckerTypeIDZone.def

@@ -434,6 +434,9 @@ SWIFT_REQUEST(TypeChecker, ExpandMacroExpansionDeclRequest,
 SWIFT_REQUEST(TypeChecker, ExpandMemberAttributeMacros,
               ArrayRef<unsigned>(Decl *),
               Cached, NoLocationInfo)
+SWIFT_REQUEST(TypeChecker, ExpandAccessorMacros,
+              ArrayRef<unsigned>(AbstractStorageDecl *),
+              Cached, NoLocationInfo)
 SWIFT_REQUEST(TypeChecker, ExpandSynthesizedMemberMacroRequest,
               ArrayRef<unsigned>(Decl *),
               Cached, NoLocationInfo)

lib/Refactoring/Refactoring.cpp

@@ -8491,7 +8491,11 @@ getMacroExpansionBuffers(MacroDecl *macro, const CustomAttr *attr, Decl *decl) {
   ASTContext &ctx = macro->getASTContext();
   llvm::SmallVector<unsigned, 2> allBufferIDs;
   if (roles.contains(MacroRole::Accessor)) {
-    // FIXME: Need to requestify.
+    if (auto storage = dyn_cast<AbstractStorageDecl>(decl)) {
+      auto bufferIDs = evaluateOrDefault(
+          ctx.evaluator, ExpandAccessorMacros{storage}, { });
+      allBufferIDs.append(bufferIDs.begin(), bufferIDs.end());
+    }
   }
 
   if (roles.contains(MacroRole::MemberAttribute)) {
@@ -8607,9 +8611,10 @@ bool RefactoringActionExpandMacro::performChange() {
 
     auto originalSourceRange = generatedInfo->originalSourceRange;
 
-    // For member macros, adjust the source range from before-the-close-brace
-    // to after-the-open-brace.
+    SmallString<64> scratchBuffer;
     if (generatedInfo->kind == GeneratedSourceInfo::MemberMacroExpansion) {
+      // For member macros, adjust the source range from before-the-close-brace
+      // to after-the-open-brace.
       ASTNode node = ASTNode::getFromOpaqueValue(generatedInfo->astNode);
       auto decl = node.dyn_cast<Decl *>();
       if (!decl)
@@ -8626,6 +8631,13 @@ bool RefactoringActionExpandMacro::performChange() {
 
       auto afterLeftBraceLoc = Lexer::getLocForEndOfToken(SM, leftBraceLoc);
       originalSourceRange = CharSourceRange(afterLeftBraceLoc, 0);
+    } else if (generatedInfo->kind ==
+                   GeneratedSourceInfo::AccessorMacroExpansion) {
+      // For accessor macros, wrap curly braces around the buffer contents.
+      scratchBuffer += "{\n";
+      scratchBuffer += rewrittenBuffer;
+      scratchBuffer += "\n}";
+      rewrittenBuffer = scratchBuffer;
     }
 
     EditConsumer.accept(SM, originalSourceRange, rewrittenBuffer);

lib/Sema/TypeCheckMacros.cpp

@@ -990,8 +990,14 @@ evaluateAttachedMacro(MacroDecl *macro, Decl *attachedTo, CustomAttr *attr,
           Lexer::getCharSourceRangeFromSourceRange(sourceMgr, *initRange);
     } else {
       // The accessors go at the end.
+      SourceLoc endLoc = storage->getEndLoc();
+      if (auto var = dyn_cast<VarDecl>(storage)) {
+        if (auto pattern = var->getParentPattern())
+          endLoc = pattern->getEndLoc();
+      }
+
       generatedOriginalSourceRange = CharSourceRange(
-         Lexer::getLocForEndOfToken(sourceMgr, storage->getEndLoc()), 0);
+         Lexer::getLocForEndOfToken(sourceMgr, endLoc), 0);
     }
 
     break;
@@ -1064,15 +1070,15 @@ evaluateAttachedMacro(MacroDecl *macro, Decl *attachedTo, CustomAttr *attr,
   return macroSourceFile;
 }
 
-void swift::expandAccessors(
+Optional<unsigned> swift::expandAccessors(
     AbstractStorageDecl *storage, CustomAttr *attr, MacroDecl *macro
 ) {
   // Evaluate the macro.
   auto macroSourceFile = evaluateAttachedMacro(macro, storage, attr,
                                                /*passParentContext*/false,
                                                MacroRole::Accessor);
   if (!macroSourceFile)
-    return;
+    return None;
 
   PrettyStackTraceDecl debugStack(
       "type checking expanded declaration macro", storage);
@@ -1098,6 +1104,22 @@ void swift::expandAccessors(
       }
     }
   }
+
+  return macroSourceFile->getBufferID();
+}
+
+ArrayRef<unsigned> ExpandAccessorMacros::evaluate(
+    Evaluator &evaluator, AbstractStorageDecl *storage
+) const {
+  llvm::SmallVector<unsigned, 1> bufferIDs;
+  storage->forEachAttachedMacro(MacroRole::Accessor,
+      [&](CustomAttr *customAttr, MacroDecl *macro) {
+        if (auto bufferID = expandAccessors(
+                storage, customAttr, macro))
+          bufferIDs.push_back(*bufferID);
+      });
+
+  return storage->getASTContext().AllocateCopy(bufferIDs);
 }
 
 Optional<unsigned>

lib/Sema/TypeCheckMacros.h

@@ -49,7 +49,7 @@ bool expandFreestandingDeclarationMacro(
 
 /// Expand the accessors for the given storage declaration based on the
 /// custom attribute that references the given macro.
-void expandAccessors(
+Optional<unsigned> expandAccessors(
     AbstractStorageDecl *storage, CustomAttr *attr, MacroDecl *macro
 );
 

lib/Sema/TypeCheckStorage.cpp

@@ -3414,10 +3414,7 @@ StorageImplInfoRequest::evaluate(Evaluator &evaluator,
   }
 
   // Expand any attached accessor macros.
-  storage->forEachAttachedMacro(MacroRole::Accessor,
-      [&](CustomAttr *customAttr, MacroDecl *macro) {
-        expandAccessors(storage, customAttr, macro);
-      });
+  (void)evaluateOrDefault(evaluator, ExpandAccessorMacros{storage}, { });
 
   bool hasWillSet = storage->getParsedAccessor(AccessorKind::WillSet);
   bool hasDidSet = storage->getParsedAccessor(AccessorKind::DidSet);

test/SourceKit/Macros/macro_basic.swift

@@ -24,6 +24,16 @@ struct S {
   var y: Int
 }
 
+struct S2 {
+  private var _storage = _Storage()
+
+  @accessViaStorage
+  var x: Int
+
+  @accessViaStorage
+  var y: Int = 17
+}
+
 // FIXME: Swift parser is not enabled on Linux CI yet.
 // REQUIRES: OS=macosx
 
@@ -92,3 +102,23 @@ struct S {
 // ATTACHED_EXPAND:   22:11-22:11 "private var _storage = _Storage()"
 // ATTACHED_EXPAND: source.edit.kind.active:
 // ATTACHED_EXPAND:   21:1-21:15 ""
+
+//##-- Refactoring expanding the first accessor macro
+// RUN: %sourcekitd-test -req=refactoring.expand.macro -pos=30:4 %s -- ${COMPILER_ARGS[@]} | %FileCheck -check-prefix=ACCESSOR1_EXPAND %s
+// ACCESSOR1_EXPAND: source.edit.kind.active:
+// ACCESSOR1_EXPAND:   31:13-31:13 "{
+// ACCESSOR1_EXPAND:  get { _storage.x }
+// ACCESSOR1_EXPAND:  set { _storage.x = newValue }
+// ACCESSOR1_EXPAND: }"
+// ACCESSOR1_EXPAND: source.edit.kind.active:
+// ACCESSOR1_EXPAND:   30:3-30:20 ""
+
+//##-- Refactoring expanding the first accessor macro
+// RUN: %sourcekitd-test -req=refactoring.expand.macro -pos=33:13 %s -- ${COMPILER_ARGS[@]} | %FileCheck -check-prefix=ACCESSOR2_EXPAND %s
+// ACCESSOR2_EXPAND: source.edit.kind.active:
+// ACCESSOR2_EXPAND:   34:14-34:18 "{
+// ACCESSOR2_EXPAND:  get { _storage.y }
+// ACCESSOR2_EXPAND:  set { _storage.y = newValue }
+// ACCESSOR2_EXPAND: }"
+// ACCESSOR2_EXPAND: source.edit.kind.active:
+// ACCESSOR2_EXPAND:   33:3-33:20 ""