[Indexing] Index macro expansion expressions.

Author: DougGregor

lib/IDE/SourceEntityWalker.cpp

@@ -590,6 +590,30 @@ ASTWalker::PreWalkResult<Expr *> SemaAnnotator::walkToExprPre(Expr *E) {
       return Action::Stop();
     // We already visited the children.
     return doSkipChildren();
+  } else if (auto ME = dyn_cast<MacroExpansionExpr>(E)) {
+    // The macro itself.
+    auto macroRef = ME->getMacroRef();
+    auto macroDecl = macroRef.getDecl();
+    auto macroRefType =
+        macroDecl->getInterfaceType().subst(macroRef.getSubstitutions());
+    if (!passReference(
+            macroDecl, macroRefType, ME->getMacroNameLoc(),
+            ReferenceMetaData(SemaReferenceKind::DeclRef, None)))
+      return Action::Stop();
+
+    // Walk the arguments, since they were written directly by the user.
+    if (auto argList = ME->getArgs()) {
+      if (!argList->walk(*this))
+        return Action::Stop();
+    }
+
+    if (auto rewritten = ME->getRewritten()) {
+      if (!rewritten->walk(*this))
+        return Action::Stop();
+    }
+
+    // Already walked the children.
+    return doSkipChildren();
   }
 
   return Action::Continue(E);

test/Index/index_macros.swift

@@ -0,0 +1,24 @@
+// RUN: %empty-directory(%t)
+//
+// RUN: %target-swift-ide-test -print-indexed-symbols -source-filename %s -enable-experimental-feature Macros | %FileCheck %s
+
+
+macro myLine: Int = _SwiftSyntaxMacros.LineMacro
+macro myFilename<T: ExpressibleByStringLiteral>: T = _SwiftSyntaxMacros.FilePathMacro
+macro myStringify<T>(_: T) -> (T, String) = _SwiftSyntaxMacros.StringifyMacro
+
+func test(x: Int) {
+  _ = #myLine
+  let _: String = #myFilename
+  _ = #myStringify(x + x)
+}
+
+// CHECK: 6:7 | macro/Swift | myLine | s:14swift_ide_test6myLineSifm | Def | rel: 0
+// CHECK: 6:15 | struct/Swift | Int | s:Si | Ref | rel: 0
+// CHECK: 7:7 | macro/Swift | myFilename | s:14swift_ide_test10myFilenamexfm | Def | rel: 0
+// CHECK: 7:21 | protocol/Swift | ExpressibleByStringLiteral | s:s26ExpressibleByStringLiteralP | Ref | rel: 0
+// CHECK: 8:7 | macro/Swift | myStringify(_:) | s:14swift_ide_test11myStringifyyx_SStxcfm | Def | rel: 0
+
+// CHECK: 11:8 | macro/Swift | myLine | s:14swift_ide_test6myLineSifm | Ref,RelCont | rel: 1
+// CHECK: 12:20 | macro/Swift | myFilename | s:14swift_ide_test10myFilenamexfm | Ref,RelCont | rel: 1
+// CHECK: 13:8 | macro/Swift | myStringify(_:) | s:14swift_ide_test11myStringifyyx_SStxcfm | Ref,RelCont | rel: 1