如何通过XcodeGen为Xcode Target添加SWIFT_ACTIVE_COMPILATION_CONDITIONS？

你之前的配置没生效，核心原因是少了buildSettings层级——XcodeGen要求所有构建设置必须嵌套在这个节点下。正确的YAML写法如下：

targets:
  # 替换成你的实际Target名称
  YourAppTarget:
    type: application
    platform: iOS
    # 这里可以补充Target的其他配置（比如sources、dependencies等）
    configs:
      Debug:
        buildSettings:
          SWIFT_ACTIVE_COMPILATION_CONDITIONS: DEBUG
      PreRelease:
        buildSettings:
          SWIFT_ACTIVE_COMPILATION_CONDITIONS: PRERELEASE
      Release:
        buildSettings:
          SWIFT_ACTIVE_COMPILATION_CONDITIONS: RELEASE

如果多个Target需要复用相同的编译条件配置，也可以把配置提到项目根节点的configs里，让Target继承：

configs:
  Debug:
    buildSettings:
      SWIFT_ACTIVE_COMPILATION_CONDITIONS: DEBUG
  PreRelease:
    buildSettings:
      SWIFT_ACTIVE_COMPILATION_CONDITIONS: PRERELEASE
  Release:
    buildSettings:
      SWIFT_ACTIVE_COMPILATION_CONDITIONS: RELEASE

targets:
  YourAppTarget:
    type: application
    platform: iOS
    # 自动继承根节点的config配置
    configs:
      Debug: {}
      PreRelease: {}
      Release: {}

配置完成后，重新执行xcodegen generate命令，生成的Xcode项目里就能看到对应环境的Active Compilation Conditions已正确配置。

内容的提问来源于stack exchange，提问作者Woochan Park