[Legacy parser] No freestanding macros in @abi

SwiftSyntaxParser is already doing this, and we already diagnosed it in Sema anyway, so we’re just moving that diagnostic earlier so the ASTGen testing mode is happy. Also adding compiler tests for it.

Author: beccadax

include/swift/AST/DiagnosticsParse.def

@@ -1568,6 +1568,11 @@ ERROR(attr_unsupported_on_target, none,
 ERROR(attr_name_unsupported_on_target, none,
       "attribute '%0' is unsupported on target '%1'", (StringRef, StringRef))
 
+// abi attribute
+ERROR(attr_abi_incompatible_kind,none,
+      "cannot use %0 in '@abi'",
+      (DescriptiveDeclKind))
+
 // availability
 ERROR(attr_availability_platform,none,
       "expected platform name or '*' for '%0' attribute", (StringRef))

lib/Parse/ParseDecl.cpp

@@ -3357,9 +3357,18 @@ ParserStatus Parser::parseNewDeclAttribute(DeclAttributes &Attributes,
     }
 
     if (abiDecl) {
-      Attributes.add(new (Context) ABIAttr(abiDecl,
-                                           AtLoc, { Loc, rParenLoc },
-                                           /*implicit=*/false));
+      auto attr = new (Context) ABIAttr(abiDecl, AtLoc, { Loc, rParenLoc },
+                                        /*implicit=*/false);
+
+      // Diagnose syntactically invalid abiDecl kind here to match behavior of
+      // Swift parser.
+      if (!attr->canAppearOnDecl(abiDecl) && !isa<PatternBindingDecl>(abiDecl)){
+        diagnose(abiDecl->getLoc(), diag::attr_abi_incompatible_kind,
+                 abiDecl->getDescriptiveKind());
+        attr->setInvalid();
+      }
+
+      Attributes.add(attr);
     }
 
     break;

test/Macros/macro_expand.swift

@@ -1,23 +1,24 @@
 // REQUIRES: swift_swift_parser, executable_test
+// REQUIRES: swift_feature_ABIAttribute
 
 // RUN: %empty-directory(%t)
 // RUN: %host-build-swift -swift-version 5 -emit-library -o %t/%target-library-name(MacroDefinition) -module-name=MacroDefinition %S/Inputs/syntax_macro_definitions.swift
 
 // Diagnostics testing
-// RUN: %target-typecheck-verify-swift -swift-version 5 -load-plugin-library %t/%target-library-name(MacroDefinition) -module-name MacroUser -DTEST_DIAGNOSTICS
+// RUN: %target-typecheck-verify-swift -swift-version 5 -load-plugin-library %t/%target-library-name(MacroDefinition) -module-name MacroUser -DTEST_DIAGNOSTICS -enable-experimental-feature ABIAttribute
 
 // Diagnostics testing by importing macros from a module
 // 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/freestanding_macro_library_2.swiftmodule %S/Inputs/freestanding_macro_library_2.swift -module-name freestanding_macro_library_2 -load-plugin-library %t/%target-library-name(MacroDefinition) -I %t
 
-// RUN: %target-typecheck-verify-swift -swift-version 5 -load-plugin-library %t/%target-library-name(MacroDefinition) -module-name MacroUser -DTEST_DIAGNOSTICS -I %t -DIMPORT_MACRO_LIBRARY
+// RUN: %target-typecheck-verify-swift -swift-version 5 -load-plugin-library %t/%target-library-name(MacroDefinition) -module-name MacroUser -DTEST_DIAGNOSTICS -I %t -DIMPORT_MACRO_LIBRARY -enable-experimental-feature ABIAttribute
 
-// RUN: not %target-swift-frontend -swift-version 5 -typecheck -load-plugin-library %t/%target-library-name(MacroDefinition) -module-name MacroUser -DTEST_DIAGNOSTICS -serialize-diagnostics-path %t/macro_expand.dia %s -emit-macro-expansion-files no-diagnostics -Rmacro-loading > %t/macro-printing.txt
+// RUN: not %target-swift-frontend -swift-version 5 -typecheck -load-plugin-library %t/%target-library-name(MacroDefinition) -module-name MacroUser -DTEST_DIAGNOSTICS -serialize-diagnostics-path %t/macro_expand.dia %s -emit-macro-expansion-files no-diagnostics -Rmacro-loading > %t/macro-printing.txt -enable-experimental-feature ABIAttribute
 // RUN: c-index-test -read-diagnostics %t/macro_expand.dia 2>&1 | %FileCheck -check-prefix CHECK-DIAGS -dump-input=always %s
 
 // RUN: %FileCheck %s  --check-prefix CHECK-MACRO-PRINTED < %t/macro-printing.txt
 
-// RUN: not %target-swift-frontend -swift-version 5 -typecheck -diagnostic-style=swift -load-plugin-library %t/%target-library-name(MacroDefinition)  -module-name MacroUser -DTEST_DIAGNOSTICS %s > %t/pretty-macro-diagnostics.txt 2>&1
+// RUN: not %target-swift-frontend -swift-version 5 -typecheck -diagnostic-style=swift -load-plugin-library %t/%target-library-name(MacroDefinition)  -module-name MacroUser -DTEST_DIAGNOSTICS %s -enable-experimental-feature ABIAttribute > %t/pretty-macro-diagnostics.txt 2>&1
 // RUN: %FileCheck %s --check-prefix PRETTY-DIAGS < %t/pretty-macro-diagnostics.txt
 
 // Debug info SIL testing
@@ -666,6 +667,29 @@ struct HasNestedType {
   #DefineComparableType
 }
 
+#if swift(>=1.0) && TEST_DIAGNOSTICS
+// Test that macros can't be used in @abi
+
+struct ABIAttrWithFreestandingMacro1 {
+  // expected-error@+1 {{cannot use pound literal in '@abi'}}
+  @abi(#varValue)
+  #varValue
+  // expected-note@-1 {{in expansion of macro 'varValue' here}}
+}
+
+struct ABIAttrWithFreestandingMacro2 {
+  // expected-error@+1 {{cannot use pound literal in '@abi'}}
+  @abi(#varValue)
+  var value: Int { 0 }
+}
+
+struct ABIAttrWithFreestandingMacro3 {
+  @abi(var value: Int)
+  #varValue
+}
+
+#endif
+
 #if TEST_DIAGNOSTICS
 @freestanding(expression)
 macro missingMacro() = #externalMacro(module: "MacroDefinition", type: "BluhBlah")

test/attr/attr_abi.swift

@@ -1286,6 +1286,7 @@ struct CustomAttrPropertyWrapper {
 }
 
 // CustomAttr for attached macro -- see Macros/macro_expand_peers.swift
+// Freestanding macro in @abi -- see Macros/macro_expand.swift
 
 // CustomAttr for result builder -- banned in '@abi'
 // Has no ABI impact on either a parameter or a decl.