Merge pull request swiftlang#74925 from DougGregor/astscope-insertion-loc-freestanding

[Macros] Put the insertion location for freestanding macros at the beginning

Author: DougGregor

lib/AST/ASTScopeCreation.cpp

@@ -290,7 +290,11 @@ ASTSourceFileScope::ASTSourceFileScope(SourceFile *SF,
     switch (*macroRole) {
     case MacroRole::Expression:
     case MacroRole::Declaration:
-    case MacroRole::CodeItem:
+    case MacroRole::CodeItem: {
+      parentLoc = SF->getMacroInsertionRange().Start;
+      break;
+    }
+
     case MacroRole::Accessor:
     case MacroRole::MemberAttribute:
     case MacroRole::Conformance:

test/Macros/Inputs/syntax_macro_definitions.swift

@@ -105,6 +105,20 @@ public struct StringifyAndTryMacro: ExpressionMacro {
   }
 }
 
+public struct TryCallThrowingFuncMacro: ExpressionMacro {
+  public static func expansion(
+    of macro: some FreestandingMacroExpansionSyntax,
+    in context: some MacroExpansionContext
+  ) -> ExprSyntax {
+    return """
+      try await {
+        print("let's throw")
+        return try await throwingFunc()
+      }()
+      """
+  }
+}
+
 struct SimpleDiagnosticMessage: DiagnosticMessage {
   let message: String
   let diagnosticID: MessageID

test/Macros/macro_expand.swift

@@ -308,6 +308,18 @@ func testStringifyWithThrows() throws {
   _ = #stringifyAndTry(maybeThrowing())
 }
 
+@available(SwiftStdlib 5.1, *)
+func throwingFunc() async throws -> Int { 5 }
+
+@freestanding(expression) macro callThrowingFunc<T>(_ body: () -> T) -> T = #externalMacro(module: "MacroDefinition", type: "TryCallThrowingFuncMacro")
+
+@available(SwiftStdlib 5.1, *)
+func testThrowingCall() async throws -> Int {
+  #callThrowingFunc {
+    [1, 2, 3, 4, 5].map { $0 + 1 }.first!
+  }
+}
+
 func testStringifyWithLocalType() throws {
   _ =  #stringify({
     struct QuailError: Error {}