[lldb/Interpreter] Fix deep copying for OptionValue classes

Some implementations of the DeepCopy function called the copy constructor that copied m_parent member instead of setting a new parent. Others just leaved the base class's members (m_parent, m_callback, m_was_set) empty.
One more problem is that not all classes override this function, e.g. OptionValueArgs::DeepCopy produces OptionValueArray instance, and Target[Process/Thread]ValueProperty::DeepCopy produces OptionValueProperty. This makes downcasting via static_cast invalid.

The patch implements idiom "virtual constructor" to fix these issues.
Add a test that checks DeepCopy for correct copying/setting all data members of the base class.

Differential Revision: https://reviews.llvm.org/D96952

Author: tkrasnukha

lldb/include/lldb/Interpreter/OptionValue.h

@@ -10,6 +10,7 @@
 #define LLDB_INTERPRETER_OPTIONVALUE_H
 
 #include "lldb/Core/FormatEntity.h"
+#include "lldb/Utility/Cloneable.h"
 #include "lldb/Utility/CompletionRequest.h"
 #include "lldb/Utility/ConstString.h"
 #include "lldb/Utility/Status.h"
@@ -87,7 +88,8 @@ class OptionValue {
 
   virtual void Clear() = 0;
 
-  virtual lldb::OptionValueSP DeepCopy() const = 0;
+  virtual lldb::OptionValueSP
+  DeepCopy(const lldb::OptionValueSP &new_parent) const;
 
   virtual void AutoComplete(CommandInterpreter &interpreter,
                             CompletionRequest &request);
@@ -306,6 +308,8 @@ class OptionValue {
     m_parent_wp = parent_sp;
   }
 
+  lldb::OptionValueSP GetParent() const { return m_parent_wp.lock(); }
+
   void SetValueChangedCallback(std::function<void()> callback) {
     assert(!m_callback);
     m_callback = std::move(callback);
@@ -317,6 +321,12 @@ class OptionValue {
   }
 
 protected:
+  using TopmostBase = OptionValue;
+
+  // Must be overriden by a derived class for correct downcasting the result of
+  // DeepCopy to it. Inherit from Cloneable to avoid doing this manually.
+  virtual lldb::OptionValueSP Clone() const = 0;
+
   lldb::OptionValueWP m_parent_wp;
   std::function<void()> m_callback;
   bool m_value_was_set; // This can be used to see if a value has been set

lldb/include/lldb/Interpreter/OptionValueArch.h

@@ -15,7 +15,7 @@
 
 namespace lldb_private {
 
-class OptionValueArch : public OptionValue {
+class OptionValueArch : public Cloneable<OptionValueArch, OptionValue> {
 public:
   OptionValueArch() = default;
 
@@ -47,8 +47,6 @@ class OptionValueArch : public OptionValue {
     m_value_was_set = false;
   }
 
-  lldb::OptionValueSP DeepCopy() const override;
-
   void AutoComplete(CommandInterpreter &interpreter,
                     lldb_private::CompletionRequest &request) override;
 

lldb/include/lldb/Interpreter/OptionValueArgs.h

@@ -13,11 +13,10 @@
 
 namespace lldb_private {
 
-class OptionValueArgs : public OptionValueArray {
+class OptionValueArgs : public Cloneable<OptionValueArgs, OptionValueArray> {
 public:
   OptionValueArgs()
-      : OptionValueArray(
-            OptionValue::ConvertTypeToMask(OptionValue::eTypeString)) {}
+      : Cloneable(OptionValue::ConvertTypeToMask(OptionValue::eTypeString)) {}
 
   ~OptionValueArgs() override = default;
 

lldb/include/lldb/Interpreter/OptionValueArray.h

@@ -15,7 +15,7 @@
 
 namespace lldb_private {
 
-class OptionValueArray : public OptionValue {
+class OptionValueArray : public Cloneable<OptionValueArray, OptionValue> {
 public:
   OptionValueArray(uint32_t type_mask = UINT32_MAX, bool raw_value_dump = false)
       : m_type_mask(type_mask), m_values(), m_raw_value_dump(raw_value_dump) {}
@@ -38,7 +38,8 @@ class OptionValueArray : public OptionValue {
     m_value_was_set = false;
   }
 
-  lldb::OptionValueSP DeepCopy() const override;
+  lldb::OptionValueSP
+  DeepCopy(const lldb::OptionValueSP &new_parent) const override;
 
   bool IsAggregateValue() const override { return true; }
 

lldb/include/lldb/Interpreter/OptionValueBoolean.h

@@ -13,7 +13,7 @@
 
 namespace lldb_private {
 
-class OptionValueBoolean : public OptionValue {
+class OptionValueBoolean : public Cloneable<OptionValueBoolean, OptionValue> {
 public:
   OptionValueBoolean(bool value)
       : m_current_value(value), m_default_value(value) {}
@@ -71,8 +71,6 @@ class OptionValueBoolean : public OptionValue {
 
   void SetDefaultValue(bool value) { m_default_value = value; }
 
-  lldb::OptionValueSP DeepCopy() const override;
-
 protected:
   bool m_current_value;
   bool m_default_value;

lldb/include/lldb/Interpreter/OptionValueChar.h

@@ -13,7 +13,7 @@
 
 namespace lldb_private {
 
-class OptionValueChar : public OptionValue {
+class OptionValueChar : public Cloneable<OptionValueChar, OptionValue> {
 public:
   OptionValueChar(char value)
       : m_current_value(value), m_default_value(value) {}
@@ -54,8 +54,6 @@ class OptionValueChar : public OptionValue {
 
   void SetDefaultValue(char value) { m_default_value = value; }
 
-  lldb::OptionValueSP DeepCopy() const override;
-
 protected:
   char m_current_value;
   char m_default_value;

lldb/include/lldb/Interpreter/OptionValueDictionary.h

@@ -15,7 +15,8 @@
 
 namespace lldb_private {
 
-class OptionValueDictionary : public OptionValue {
+class OptionValueDictionary
+    : public Cloneable<OptionValueDictionary, OptionValue> {
 public:
   OptionValueDictionary(uint32_t type_mask = UINT32_MAX,
                         bool raw_value_dump = true)
@@ -39,7 +40,8 @@ class OptionValueDictionary : public OptionValue {
     m_value_was_set = false;
   }
 
-  lldb::OptionValueSP DeepCopy() const override;
+  lldb::OptionValueSP
+  DeepCopy(const lldb::OptionValueSP &new_parent) const override;
 
   bool IsAggregateValue() const override { return true; }
 

lldb/include/lldb/Interpreter/OptionValueEnumeration.h

@@ -19,7 +19,8 @@
 
 namespace lldb_private {
 
-class OptionValueEnumeration : public OptionValue {
+class OptionValueEnumeration
+    : public Cloneable<OptionValueEnumeration, OptionValue> {
 public:
   typedef int64_t enum_type;
   struct EnumeratorInfo {
@@ -49,8 +50,6 @@ class OptionValueEnumeration : public OptionValue {
     m_value_was_set = false;
   }
 
-  lldb::OptionValueSP DeepCopy() const override;
-
   void AutoComplete(CommandInterpreter &interpreter,
                     CompletionRequest &request) override;
 

lldb/include/lldb/Interpreter/OptionValueFileColonLine.h

@@ -16,7 +16,8 @@
 
 namespace lldb_private {
 
-class OptionValueFileColonLine : public OptionValue {
+class OptionValueFileColonLine :
+    public Cloneable<OptionValueFileColonLine, OptionValue> {
 public:
   OptionValueFileColonLine();
   OptionValueFileColonLine(const llvm::StringRef input);
@@ -38,8 +39,6 @@ class OptionValueFileColonLine : public OptionValue {
     m_column_number = LLDB_INVALID_COLUMN_NUMBER;
   }
 
-  lldb::OptionValueSP DeepCopy() const override;
-
   void AutoComplete(CommandInterpreter &interpreter,
                     CompletionRequest &request) override;
 

lldb/include/lldb/Interpreter/OptionValueFileSpec.h

@@ -16,7 +16,7 @@
 
 namespace lldb_private {
 
-class OptionValueFileSpec : public OptionValue {
+class OptionValueFileSpec : public Cloneable<OptionValueFileSpec, OptionValue> {
 public:
   OptionValueFileSpec(bool resolve = true);
 
@@ -45,8 +45,6 @@ class OptionValueFileSpec : public OptionValue {
     m_data_mod_time = llvm::sys::TimePoint<>();
   }
 
-  lldb::OptionValueSP DeepCopy() const override;
-
   void AutoComplete(CommandInterpreter &interpreter,
                     CompletionRequest &request) override;
 

lldb/include/lldb/Interpreter/OptionValueFileSpecList.h

@@ -16,12 +16,13 @@
 
 namespace lldb_private {
 
-class OptionValueFileSpecList : public OptionValue {
+class OptionValueFileSpecList
+    : public Cloneable<OptionValueFileSpecList, OptionValue> {
 public:
   OptionValueFileSpecList() = default;
 
-  OptionValueFileSpecList(const FileSpecList &current_value)
-      : m_current_value(current_value) {}
+  OptionValueFileSpecList(const OptionValueFileSpecList &other)
+      : Cloneable(other), m_current_value(other.GetCurrentValue()) {}
 
   ~OptionValueFileSpecList() override = default;
 
@@ -42,8 +43,6 @@ class OptionValueFileSpecList : public OptionValue {
     m_value_was_set = false;
   }
 
-  lldb::OptionValueSP DeepCopy() const override;
-
   bool IsAggregateValue() const override { return true; }
 
   // Subclass specific functions
@@ -64,6 +63,8 @@ class OptionValueFileSpecList : public OptionValue {
   }
 
 protected:
+  lldb::OptionValueSP Clone() const override;
+
   mutable std::recursive_mutex m_mutex;
   FileSpecList m_current_value;
 };

lldb/include/lldb/Interpreter/OptionValueFormat.h

@@ -13,7 +13,8 @@
 
 namespace lldb_private {
 
-class OptionValueFormat : public OptionValue {
+class OptionValueFormat
+    : public Cloneable<OptionValueFormat, OptionValue> {
 public:
   OptionValueFormat(lldb::Format value)
       : m_current_value(value), m_default_value(value) {}
@@ -39,8 +40,6 @@ class OptionValueFormat : public OptionValue {
     m_value_was_set = false;
   }
 
-  lldb::OptionValueSP DeepCopy() const override;
-
   // Subclass specific functions
 
   lldb::Format GetCurrentValue() const { return m_current_value; }

lldb/include/lldb/Interpreter/OptionValueFormatEntity.h

@@ -14,7 +14,8 @@
 
 namespace lldb_private {
 
-class OptionValueFormatEntity : public OptionValue {
+class OptionValueFormatEntity
+    : public Cloneable<OptionValueFormatEntity, OptionValue> {
 public:
   OptionValueFormatEntity(const char *default_format);
 
@@ -33,8 +34,6 @@ class OptionValueFormatEntity : public OptionValue {
 
   void Clear() override;
 
-  lldb::OptionValueSP DeepCopy() const override;
-
   void AutoComplete(CommandInterpreter &interpreter,
                     CompletionRequest &request) override;
 

lldb/include/lldb/Interpreter/OptionValueLanguage.h

@@ -15,7 +15,7 @@
 
 namespace lldb_private {
 
-class OptionValueLanguage : public OptionValue {
+class OptionValueLanguage : public Cloneable<OptionValueLanguage, OptionValue> {
 public:
   OptionValueLanguage(lldb::LanguageType value)
       : m_current_value(value), m_default_value(value) {}
@@ -42,8 +42,6 @@ class OptionValueLanguage : public OptionValue {
     m_value_was_set = false;
   }
 
-  lldb::OptionValueSP DeepCopy() const override;
-
   // Subclass specific functions
 
   lldb::LanguageType GetCurrentValue() const { return m_current_value; }

lldb/include/lldb/Interpreter/OptionValuePathMappings.h

@@ -14,7 +14,8 @@
 
 namespace lldb_private {
 
-class OptionValuePathMappings : public OptionValue {
+class OptionValuePathMappings
+    : public Cloneable<OptionValuePathMappings, OptionValue> {
 public:
   OptionValuePathMappings(bool notify_changes)
       : m_notify_changes(notify_changes) {}
@@ -37,8 +38,6 @@ class OptionValuePathMappings : public OptionValue {
     m_value_was_set = false;
   }
 
-  lldb::OptionValueSP DeepCopy() const override;
-
   bool IsAggregateValue() const override { return true; }
 
   // Subclass specific functions

lldb/include/lldb/Interpreter/OptionValueProperties.h

@@ -18,24 +18,27 @@
 #include "lldb/Utility/ConstString.h"
 
 namespace lldb_private {
+class Properties;
 
 class OptionValueProperties
-    : public OptionValue,
+    : public Cloneable<OptionValueProperties, OptionValue>,
       public std::enable_shared_from_this<OptionValueProperties> {
 public:
   OptionValueProperties() = default;
 
   OptionValueProperties(ConstString name);
 
-  OptionValueProperties(const OptionValueProperties &global_properties);
-
   ~OptionValueProperties() override = default;
 
   Type GetType() const override { return eTypeProperties; }
 
   void Clear() override;
 
-  lldb::OptionValueSP DeepCopy() const override;
+  static lldb::OptionValuePropertiesSP
+  CreateLocalCopy(const Properties &global_properties);
+
+  lldb::OptionValueSP
+  DeepCopy(const lldb::OptionValueSP &new_parent) const override;
 
   Status
   SetValueFromString(llvm::StringRef value,

lldb/include/lldb/Interpreter/OptionValueRegex.h

@@ -14,7 +14,7 @@
 
 namespace lldb_private {
 
-class OptionValueRegex : public OptionValue {
+class OptionValueRegex : public Cloneable<OptionValueRegex, OptionValue> {
 public:
   OptionValueRegex(const char *value = nullptr)
       : m_regex(llvm::StringRef::withNullAsEmpty(value)),
@@ -38,8 +38,6 @@ class OptionValueRegex : public OptionValue {
     m_value_was_set = false;
   }
 
-  lldb::OptionValueSP DeepCopy() const override;
-
   // Subclass specific functions
   const RegularExpression *GetCurrentValue() const {
     return (m_regex.IsValid() ? &m_regex : nullptr);

lldb/include/lldb/Interpreter/OptionValueSInt64.h

@@ -14,7 +14,7 @@
 
 namespace lldb_private {
 
-class OptionValueSInt64 : public OptionValue {
+class OptionValueSInt64 : public Cloneable<OptionValueSInt64, OptionValue> {
 public:
   OptionValueSInt64() = default;
 
@@ -44,8 +44,6 @@ class OptionValueSInt64 : public OptionValue {
     m_value_was_set = false;
   }
 
-  lldb::OptionValueSP DeepCopy() const override;
-
   // Subclass specific functions
 
   const int64_t &operator=(int64_t value) {

lldb/include/lldb/Interpreter/OptionValueString.h

@@ -17,7 +17,7 @@
 
 namespace lldb_private {
 
-class OptionValueString : public OptionValue {
+class OptionValueString : public Cloneable<OptionValueString, OptionValue> {
 public:
   typedef Status (*ValidatorCallback)(const char *string, void *baton);
 
@@ -78,8 +78,6 @@ class OptionValueString : public OptionValue {
     m_value_was_set = false;
   }
 
-  lldb::OptionValueSP DeepCopy() const override;
-
   // Subclass specific functions
 
   Flags &GetOptions() { return m_options; }