[lldb] Add unittests for SwiftLanguageRuntime demangling functions

lldb/source/Plugins/LanguageRuntime/Swift/SwiftLanguageRuntimeNames.cpp

@@ -83,24 +83,26 @@ static bool IsSwiftAsyncFunctionSymbol(swift::Demangle::NodePointer node) {
     return false;
   if (hasChild(node, Node::Kind::AsyncSuspendResumePartialFunction))
     return false;
-
-  // Peel off layers over top of Function nodes.
-  switch (node->getFirstChild()->getKind()) {
-  case Node::Kind::Static:
-  case Node::Kind::ExplicitClosure:
+  // Peel off a Static node. If it exists, there will be a single instance and a
+  // top level node.
+  if (node->getFirstChild()->getKind() == Node::Kind::Static)
     node = node->getFirstChild();
-    break;
-  default:
-    break;
-  }
 
-  return childAtPath(node,
-                     {Node::Kind::Function, Node::Kind::Type,
-                      Node::Kind::FunctionType, Node::Kind::AsyncAnnotation}) ||
-         childAtPath(node,
-                     {Node::Kind::Function, Node::Kind::Type,
-                      Node::Kind::DependentGenericType, Node::Kind::Type,
-                      Node::Kind::FunctionType, Node::Kind::AsyncAnnotation});
+  // Get the ExplicitClosure or Function node.
+  // For nested closures in Swift, the demangle tree is inverted: the
+  // inner-most closure is the top-most ExplicitClosure node.
+  NodePointer func_node = [&] {
+    if (NodePointer func = childAtPath(node, Node::Kind::Function))
+      return func;
+    return childAtPath(node, Node::Kind::ExplicitClosure);
+  }();
+
+  return childAtPath(func_node, {Node::Kind::Type, Node::Kind::FunctionType,
+                                 Node::Kind::AsyncAnnotation}) ||
+         childAtPath(func_node,
+                     {Node::Kind::Type, Node::Kind::DependentGenericType,
+                      Node::Kind::Type, Node::Kind::FunctionType,
+                      Node::Kind::AsyncAnnotation});
 }
 
 bool SwiftLanguageRuntime::IsSwiftAsyncFunctionSymbol(StringRef name) {

lldb/unittests/Symbol/CMakeLists.txt

@@ -1,6 +1,7 @@
 set(SWIFT_SOURCES
   TestSwiftASTContext.cpp
   TestTypeSystemSwiftTypeRef.cpp
+  TestSwiftDemangler.cpp
 )
 set(SWIFT_LIBS
   lldbPluginTypeSystemSwift

lldb/unittests/Symbol/TestSwiftDemangler.cpp

@@ -0,0 +1,87 @@
+#include "gtest/gtest.h"
+
+#include "Plugins/LanguageRuntime/Swift/SwiftLanguageRuntime.h"
+
+using namespace lldb;
+using namespace lldb_private;
+using namespace llvm;
+static constexpr auto IsSwiftMangledName =
+    SwiftLanguageRuntime::IsSwiftMangledName;
+static constexpr auto IsAnySwiftAsyncFunctionSymbol = [](StringRef name) {
+  return SwiftLanguageRuntime::IsAnySwiftAsyncFunctionSymbol(name);
+};
+
+TEST(TestSwiftDemangleAsyncNames, BasicAsync) {
+  // "sayBasic" == a basic async function
+  // "sayGeneric" == a generic async function
+  SmallVector<StringRef> basic_funclets = {
+      "$s1a8sayBasicyySSYaF",
+      "$s1a8sayBasicyySSYaFTY0_",
+      "$s1a8sayBasicyySSYaFTQ1_",
+      "$s1a8sayBasicyySSYaFTY2_",
+  };
+  SmallVector<StringRef> generic_funclets = {
+      "$s1a10sayGenericyyxYalF",
+      "$s1a10sayGenericyyxYalFTY0_",
+      "$s1a10sayGenericyyxYalFTQ1_",
+      "$s1a10sayGenericyyxYalFTY2_",
+  };
+  for (StringRef async_name :
+       llvm::concat<StringRef>(basic_funclets, generic_funclets)) {
+    EXPECT_TRUE(IsSwiftMangledName(async_name)) << async_name;
+    EXPECT_TRUE(IsAnySwiftAsyncFunctionSymbol(async_name)) << async_name;
+  }
+}
+
+TEST(TestSwiftDemangleAsyncNames, ClosureAsync) {
+  // These are all async closures
+  SmallVector<StringRef> nested1_funclets = {
+      // Nesting level 1: a closure inside a function.
+      "$s1a8sayHelloyyYaFyypYacfU_",     "$s1a8sayHelloyyYaFyypYacfU_TY0_",
+      "$s1a8sayHelloyyYaFyypYacfU_TQ1_", "$s1a8sayHelloyyYaFyypYacfU_TY2_",
+      "$s1a8sayHelloyyYaFyypYacfU_TQ3_", "$s1a8sayHelloyyYaFyypYacfU_TY4_",
+      "$s1a8sayHelloyyYaFyypYacfU_TQ5_", "$s1a8sayHelloyyYaFyypYacfU_TY6_"};
+  SmallVector<StringRef> nested2_funclets1 = {
+      // Nesting level 2: a closure inside a closure.
+      "$s1a8sayHelloyyYaFyypYacfU_yypYacfU_",
+      "$s1a8sayHelloyyYaFyypYacfU_yypYacfU_TY0_",
+      "$s1a8sayHelloyyYaFyypYacfU_yypYacfU_TQ1_",
+      "$s1a8sayHelloyyYaFyypYacfU_yypYacfU_TY2_",
+  };
+  SmallVector<StringRef> nested2_funclets2 = {
+      // Nesting level 2: another closure, same level as the previous one.
+      "$s1a8sayHelloyyYaFyypYacfU_yypYacfU0_",
+      "$s1a8sayHelloyyYaFyypYacfU_yypYacfU0_TY0_",
+      "$s1a8sayHelloyyYaFyypYacfU_yypYacfU0_TQ1_",
+      "$s1a8sayHelloyyYaFyypYacfU_yypYacfU0_TY2_",
+  };
+  SmallVector<StringRef> nested2_funclets_top_not_async = {
+      // Also nesting level 2: but this time, the top level function is _not_
+      // async!
+      "$s1a18myNonAsyncFunctionyyFyyYacfU_SiypYacfU_SSypYacfU0_",
+      "$s1a18myNonAsyncFunctionyyFyyYacfU_SiypYacfU_SSypYacfU0_TY0_",
+      "$s1a18myNonAsyncFunctionyyFyyYacfU_SiypYacfU_SSypYacfU0_TQ1_",
+      "$s1a18myNonAsyncFunctionyyFyyYacfU_SiypYacfU_SSypYacfU0_TY2_"};
+
+  for (StringRef async_name : llvm::concat<StringRef>(
+           nested1_funclets, nested2_funclets1, nested2_funclets2,
+           nested2_funclets_top_not_async)) {
+    EXPECT_TRUE(IsSwiftMangledName(async_name)) << async_name;
+    EXPECT_TRUE(IsAnySwiftAsyncFunctionSymbol(async_name)) << async_name;
+  }
+}
+
+TEST(TestSwiftDemangleAsyncNames, StaticAsync) {
+  // static async functions
+  SmallVector<StringRef> async_names = {
+      "$s1a6StructV9sayStaticyySSYaFZ"
+      "$s1a6StructV9sayStaticyySSYaFZTY0_",
+      "$s1a6StructV9sayStaticyySSYaFZTQ1_",
+      "$s1a6StructV9sayStaticyySSYaFZTY2_",
+  };
+
+  for (StringRef async_name : async_names) {
+    EXPECT_TRUE(IsSwiftMangledName(async_name)) << async_name;
+    EXPECT_TRUE(IsAnySwiftAsyncFunctionSymbol(async_name)) << async_name;
+  }
+}