Add setting gating the new po, initially disabled by default

Author: kastiglione

lldb/include/lldb/Target/Target.h

@@ -215,6 +215,8 @@ class TargetProperties : public Properties {
 
   bool GetSwiftAutoImportFrameworks() const;
 
+  bool GetSwiftUseNewPrintObject() const;
+
   bool GetEnableAutoImportClangModules() const;
 
   bool GetUseAllCompilerFlags() const;

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

@@ -1094,8 +1094,9 @@ llvm::Error SwiftLanguageRuntime::GetObjectDescription(Stream &str,
   if (object.IsUninitializedReference())
     return llvm::createStringError("<uninitialized>");
 
-  if (printObjectViaPointer(str, object, GetProcess()))
-    return llvm::Error::success();
+  if (GetProcess().GetTarget().GetSwiftUseNewPrintObject())
+    if (printObjectViaPointer(str, object, GetProcess()))
+      return llvm::Error::success();
 
   std::string expr_string;
 

lldb/source/Target/Target.cpp

@@ -4705,6 +4705,18 @@ bool TargetProperties::GetSwiftAutoImportFrameworks() const {
       idx, g_target_properties[idx].default_uint_value != 0);
 }
 
+bool TargetProperties::GetSwiftUseNewPrintObject() const {
+  const Property *exp_property =
+      m_collection_sp->GetPropertyAtIndex(ePropertyExperimental);
+  OptionValueProperties *exp_values =
+      exp_property->GetValue()->GetAsProperties();
+  if (exp_values)
+    return exp_values
+        ->GetPropertyAtIndexAs<bool>(ePropertySwiftUseNewPrintObject)
+        .value_or(false);
+  return false;
+}
+
 void TargetProperties::SetUseDIL(ExecutionContext *exe_ctx, bool b) {
   const Property *exp_property =
       m_collection_sp->GetPropertyAtIndex(ePropertyExperimental, exe_ctx);

lldb/source/Target/TargetProperties.td

@@ -37,6 +37,9 @@ let Definition = "target_experimental" in {
   def SwiftCacheTaskPointerLocation: Property<"swift-cache-task-pointer-location", "Boolean">,
     DefaultTrue,
     Desc<"Enables caching of task pointers inside the swift tasks plugin">;
+  def SwiftUseNewPrintObject: Property<"swift-use-new-po", "Boolean">,
+    DefaultFalse,
+    Desc<"If true, use the new Swift po implementation.">;
   def UseDIL : Property<"use-DIL", "Boolean">,
     Global, DefaultTrue,
     Desc<"If true, use the DIL implementation for frame variable evaluation.">;

lldb/test/API/lang/swift/expression/error_reporting/TestSwiftExpressionErrorReporting.py

@@ -68,6 +68,8 @@ def test_missing_type(self):
         target, process, thread, bkpt = lldbutil.run_to_source_breakpoint(
             self, 'break here', lldb.SBFileSpec('main.swift'))
 
+        self.runCmd("settings set target.experimental.swift-use-new-po true")
+
         options = lldb.SBExpressionOptions()
         value = self.frame().EvaluateExpression("strct", options)
         def check(value):
@@ -84,7 +86,6 @@ def check(value):
         # This succeeds using stringForPrintObject(_:mangledTypeName:), which
         # doesn't require the type to be available.
         # Note: (?s)^(?!.*<pattern>) checks that the pattern is not found.
-        # self.runCmd("log enable lldb formatters")
         self.expect(
             "dwim-print -O -- strct",
             patterns=["(?s)^(?!.*error: Missing type)", "properties : true"],
@@ -93,4 +94,3 @@ def check(value):
         process.Continue()
         self.expect('expression -O -- number', error=True,
                     substrs=['self', 'not', 'found'])
-