使用Swift Package Manager怎样区分debug和release打包环境

SPM自身并不支持根据打包环境自适应是否依赖某些库。
为了解决这个问题可引入一个私有库，打包前修改该私有库即可实现release下不引用某些库的目的。

import PackageDescription
// 标记是否为测试环境，isDebug为false则不依赖FLEX和LookinServer两个库，为true则依赖这两个库
// 将该私有库放入工程目录下，build前通过脚本修改`isDebug`的值即可自适应依赖
let isDebug = false

var debugDependencies: [Package.Dependency] = []
var debugTargetDep: [PackageDescription.Target.Dependency] = []
if isDebug {
     debugDependencies = [
        .package(url: "https://github.com/FLEXTool/FLEX.git", from: "5.22.10"),
        .package(url: "https://github.com/QMUI/LookinServer.git", from: "1.2.8"),
    ]
    debugTargetDep = [
        .product(name: "FLEX", package: "FLEX"),
        .product(name: "LookinServer", package: "LookinServer"),
    ]
}


let package = Package(
    name: "MyLibrary",
    platforms: [
        .iOS(.v15)
    ],
    products: [
        // Products define the executables and libraries a package produces, making them visible to other packages.
        .library(
            name: "MyLibrary",
            targets: ["MyLibrary"]),
    ],
    dependencies: [] + debugDependencies,
    targets: [
        // Targets are the basic building blocks of a package, defining a module or a test suite.
        // Targets can depend on other targets in this package and products from dependencies.
        .target(
            name: "MyLibrary",
            dependencies: [] + debugTargetDep
        )
    ]
)