Building project fails on missing cpp.ex file

I’m following a video tutorial for creating editor plugins, since I’m on a Mac I’m using Xcode, for now I’ve called the plugin ‘BlockPlugin’ and the project ‘BlockProject’.

I’ve created a new project (C++ basic template), after creating the project I can build the project in Xcode and I get a message in the Unreal Editor that a hot reload has taken place.

Following along with the tutorial I’ve created the following files in my project folder:

Plugins/BlockPlugin/BlockPlugin.uplugin

{
    "FileVersion": 3,
    "FriendlyName":"Block Plugin",
    "Version": 1,
    "VersionName": "1.0",
    "EngineVersion":1579795,
    "Description": "This describes the plugin",
    "Category": "Smeis.Plugin",
    "CreatedBy": "My Name",
    "CreatedByUrl": "URL",

    "Modules": [
        {
            "Name": "BlockPlugin",
            "Type": "Editor"
        }
    ]
}

Plugins/BlockPlugin/Source/BlockPlugin/BlockPlugin.Build.cs

using UnrealBuildTool;

public class BlockPlugin : ModuleRules
{
    public BlockPlugin(TargetInfo target)
    {
        PrivateIncludePaths.AddRange(new string[] { "BlockPlugin/Private" });

        PrivateDependencyModuleNames.AddRange(
                new[]
                {
                    "Engine",
                    "UnrealEd",
                    "InputCore",
                    "Core",
                    "Slate",
                    "SlateCore",
                    "EditorStyle",
                    "CoreUObject"
                });
      }
  }

And in Plugins/BlockPlugin/Source/BlockPlugin/Private I’ve created the following files:

BlockPluginPch.h

 #include "ModuleManager.h"

Module.h

#pragma once

DECLARE_LOG_CATEGORY_EXTERN(ModuleLog, Log, All);

class Module : public IModuleInterface
{
public:
  Module();
  
  virtual void StartupModule() override;
  virtual void ShutdownModule() override;
};

Module.cpp

#include "BlockPluginPch.h"
#include "Module.h"

IMPLEMENT_MODULE(Module, BlockPlugin);
DEFINE_LOG_CATEGORY(ModuleLog);

Module::Module()
{
  
}

void Module::StartupModule()
{
  UE_LOG(ModuleLog, Warning, TEXT("Hello from BlockPlugin!"));
}

void Module::ShutdownModule()
{
  
}

After creating the files I have Unreal Editor refresh the Xcode project. However, when I try to build the project it fails. I have 4 targets in Xcode. The targets BlockProject_Index and BlockProject_Build work fine though I’m not really sure yet what they’re for. Building the BlockProject target fails (I’m assuming that this is the one I need to build to reload the project in the editor).

The build script RocketBuild.sh fails complaining that it can’t find Plugins/BlockPlugin/Source/BlockPlugin/Private/Module.cpp.ex.

Could someone please tell me what a cpp.ex file is and what I’ve done wrong to get this error?