Merge pull request #61354 from apple/egorzhdan/cxx-docs-update

[cxx-interop][docs] Update getting started guide

docs/CppInteroperability/GettingStartedWithC++Interop.md

@@ -11,22 +11,20 @@ This document is designed to get you started with bidirectional API-level intero
 
 ## Creating a Module to contain your C++ source code
 
-- Create a new C++ implementation and header file
+- Create a new target in Xcode via _File_ | _New_ | _Target_, select _Library_.
-- For this example we will call the files Cxx, so we should have a Cxx.cpp and Cxx.hpp.
+- Within the directory of the newly created target, create a new C++ implementation and header file
+- For this example we will call the files CxxTest, so we should have a CxxTest.cpp and CxxTest.hpp.
 - Next create an empty file and call it `module.modulemap`, in this file create the module for your source code, and define your C++ header (`requires cplusplus` isn't required but it's convention for C++ modules, especially if they use C++ features).
 
 ```
-//In module.modulemap
+// In module.modulemap
-module Cxx {
+module CxxTest {
-    //note that your header should be the file that contains your method implementations
+    header "CxxTest.hpp"
-    header "Cxx.hpp"
     requires cplusplus
 }
 ```
 
-- Move the newly created files (Cxx.cpp, Cxx.hpp, module.modulemap) into a separate directory (this should remain in your project directory)
+<img width="127" alt="cxx-interop-ctest" src="https://user-images.githubusercontent.com/3801618/192995602-f37137f3-ec15-4fdd-bf2c-591728945a68.png">
-
-<img width="252" alt="Screen Shot 2022-02-26 at 9 14 06 PM" src="https://user-images.githubusercontent.com/62521716/155867937-9d9d6c62-4418-414d-bc4e-5d12c2055022.png">
 
 ## Adding C++ to an Xcode project
 - In your xcode project, follow the steps [Creating a Module to contain your C++ source code](#creating-a-module-to-contain-your-c-source-code) in your project directory
@@ -35,12 +33,12 @@ Add the C++ module to the include path and enable C++ interop:
 - Navigate to your project directory
 - In `Project` navigate to `Build Settings` -> `Swift Compiler`
 - Under `Custom Flags` -> `Other Swift Flags` add`-enable-experimental-cxx-interop`
-- Under `Search Paths` -> `Import Paths` add your search path to the C++ module (i.e, `./ProjectName/Cxx`). Repeat this step in `Other Swift Flags`
+- Under `Search Paths` -> `Import Paths` add your search path to the C++ module (i.e, `./ProjectName/CxxTest`). Repeat this step in `Other Swift Flags`
 
 ```
 //Add to Other Swift Flags and Import Paths respectively
 -enable-experimental-cxx-interop
--I./ProjectName/Cxx
+-I./ProjectName/CxxTest
 ```
 
 - This should now allow your to import your C++ Module into any `.swift` file.
@@ -48,21 +46,21 @@ Add the C++ module to the include path and enable C++ interop:
 ```
 //In ContentView.swift
 import SwiftUI
-import Cxx
+import CxxTest
 
 struct ContentView: View {
     var body: some View {
-        Text("Cxx function result: \(cxxFunction(7))")
+        Text("CxxTest function result: \(cxxFunction(7))")
             .padding()
     }
 }
 ```
 
 ```
-//In Cxx.hpp
+// In CxxTest.hpp
 
-#ifndef Cxx_hpp
+#ifndef CxxTest_hpp
-#define Cxx_hpp
+#define CxxTest_hpp
 
 int cxxFunction(int n);
 
@@ -70,9 +68,9 @@ int cxxFunction(int n);
 ```
 
 ```
-//In Cxx.cpp
+// In CxxTest.cpp
 
-#include "Cxx.hpp"
+#include "CxxTest.hpp"
 
 int cxxFunction(int n) {
     return n;
@@ -101,24 +99,24 @@ let package = Package(
     platforms: [.macOS(.v12)],
     products: [
         .library(
-            name: "Cxx",
+            name: "CxxTest",
-            targets: ["Cxx"]),
+            targets: ["CxxTest"]),
         .library(
             name: "CxxInterop",
             targets: ["CxxInterop"]),
     ],
     targets: [
         .target(
-            name: "Cxx",
+            name: "CxxTest",
             dependencies: []
         ),
         .executableTarget(
             name: "CxxInterop",
-            dependencies: ["Cxx"],
+            dependencies: ["CxxTest"],
             path: "./Sources/CxxInterop",
             sources: [ "main.swift" ],
             swiftSettings: [.unsafeFlags([
-                "-I", "Sources/Cxx",
+                "-I", "Sources/CxxTest",
                 "-enable-experimental-cxx-interop",
             ])]
         ),
@@ -132,7 +130,7 @@ let package = Package(
 ```
 //In main.swift
 
-import Cxx
+import CxxTest
 
 public struct CxxInterop {
 
@@ -151,12 +149,12 @@ After creating your project follow the steps [Creating a Module to contain your
 
 - Create a `CMakeLists.txt` file and configure for your project
 - In`add_library` invoke `cxx-support` with the path to the C++ implementation file
-- Add the `target_include_directories` with `cxx-support` and path to the C++ Module `${CMAKE_SOURCE_DIR}/Sources/Cxx`
+- Add the `target_include_directories` with `cxx-support` and path to the C++ Module `${CMAKE_SOURCE_DIR}/Sources/CxxTest`
 - Add the `add_executable` to the specific files/directory you would like to generate source, with`SHELL:-enable-experimental-cxx-interop`.
 - In the example below we will be following the file structure used in [Creating a Swift Package](#Creating-a-Swift-Package)
 
 ```
-//In CMakeLists.txt
+// In CMakeLists.txt
 
 cmake_minimum_required(VERSION 3.18)
 
@@ -166,14 +164,12 @@ set(CMAKE_CXX_STANDARD 11)
 set(CMAKE_CXX_STANDARD_REQUIRED YES)
 set(CMAKE_CXX_EXTENSIONS OFF)
 
-add_library(cxx-support ./Sources/Cxx/Cxx.cpp)
+add_library(cxx-support ./Sources/CxxTest/CxxTest.cpp)
 target_compile_options(cxx-support PRIVATE
-  -I${SWIFT_CXX_TOOLCHAIN}/usr/include/c++/v1
   -fno-exceptions
-  -fignore-exceptions
+  -fignore-exceptions)
-  -nostdinc++)
 target_include_directories(cxx-support PUBLIC
-  ${CMAKE_SOURCE_DIR}/Sources/Cxx)
+  ${CMAKE_SOURCE_DIR}/Sources/CxxTest)
 
 add_executable(CxxInterop ./Sources/CxxInterop/main.swift)
 target_compile_options(CxxInterop PRIVATE
@@ -185,7 +181,7 @@ target_link_libraries(CxxInterop PRIVATE cxx-support)
 ```
 //In main.swift
 
-import Cxx
+import CxxTest
 
 public struct CxxInterop {
     public static func main() {