[lldb][NFC] Factor out CommandObject code filtering results based on scope

[fdeazeve]

Summary

We will need this code in a subsequent commit.

[jasonmolenda]

LGTM.

lldb/source/Commands/CommandObjectFrame.cpp

case eValueTypeVariableThreadLocal:
       return "THREAD: ";
     default:
       break;
     }
 
     return llvm::StringRef();
   }
 
+  /// Returns true if `scope` matches any of the options in `m_option_variable`.
+  bool ScopeRequested(lldb::ValueType scope) {
+    switch (scope) {
+    case eValueTypeVariableGlobal:
+    case eValueTypeVariableStatic:
+      return m_option_variable.show_globals;
+    case eValueTypeVariableArgument:
+      return m_option_variable.show_args;
+    case eValueTypeVariableLocal:
+      return m_option_variable.show_locals;
+    case eValueTypeInvalid:
+    case eValueTypeRegister:
+    case eValueTypeRegisterSet:
+    case eValueTypeConstResult:
+    case eValueTypeVariableThreadLocal:
+      return false;
+    }
+  }
+
   bool DoExecute(Args &command, CommandReturnObject &result) override {
     // No need to check "frame" for validity as eCommandRequiresFrame ensures
     // it is valid
     StackFrame *frame = m_exe_ctx.GetFramePtr();
 
     Stream &s = result.GetOutputStream();
 
     // Be careful about the stack frame, if any summary formatter runs code, it
if (variable_list) {
           }
         }
       } else // No command arg specified.  Use variable_list, instead.
       {
         const size_t num_variables = variable_list->GetSize();
         if (num_variables > 0) {
           for (size_t i = 0; i < num_variables; i++) {
             var_sp = variable_list->GetVariableAtIndex(i);
-            switch (var_sp->GetScope()) {
-            case eValueTypeVariableGlobal:
-              if (!m_option_variable.show_globals)
+            if (!ScopeRequested(var_sp->GetScope()))
                 continue;
-              break;
-            case eValueTypeVariableStatic:
-              if (!m_option_variable.show_globals)
-                continue;
-              break;
-            case eValueTypeVariableArgument:
-              if (!m_option_variable.show_args)
-                continue;
-              break;
-            case eValueTypeVariableLocal:
-              if (!m_option_variable.show_locals)
-                continue;
-              break;
-            default:
-              continue;
-              break;
-            }
             std::string scope_string;
             if (m_option_variable.show_scope)
               scope_string = GetScopeString(var_sp).str();
 
             // Use the variable object code to make sure we are using the same
             // APIs as the public API will be using...
             valobj_sp = frame->GetValueObjectForFrameVariable(
                 var_sp, m_varobj_options.use_dynamic);