Generating Code And Other Mischief With Swift Package Manager Plugins - 360iDev, Denver, CO, August 2022

It’s the build tooling step everyone hates: “Now, add a new Run Script Build Phase.” The Swift and Xcode teams have worked to try to make things at least a little bit better for things which need to happen at build time by adding Build Tool Plugins and Command Plugins to Swift Package manager.

In this talk, you’ll get a look at how to set these up to generate code and documentation, plus a look at some other silly things you can make it do.

Sample App: https://github.com/designatednerd/RadioactiveCat
Sample Plugin: https://github.com/designatednerd/DatedImageGenerator

Transcript

1. GENERATING CODE AND OTHER MISCHIEF WITH
   SWIFT PACKAGE MANAGER PLUGINS
   360IDEV | DENVER, CO | AUGUST 2022
   ELLEN SHAPIRO | @DESIGNATEDNERD | GUSTO.COM
   

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6. ALCATRAZ
   

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18. !
    XCODE GHOST
    

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19. !
    XCODE GHOST
    

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20. !
    STRAWHORSE
    

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23. !
    

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25. XCODE SOURCE EXTENSIONS
    

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26. REQUIRED HOST MAC APP
    

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27. REQUIRED HOST MAC APP
    ▸
    !
    Can now be distributed easily on the Mac App store
    

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28. REQUIRED HOST MAC APP
    ▸
    !
    Can now be distributed easily on the Mac App store
    ▸
    "
    Sandboxing restrictions
    

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29. REQUIRED HOST MAC APP
    ▸
    !
    Can now be distributed easily on the Mac App store
    ▸
    "
    Sandboxing restrictions
    ▸
    #
    Often winds up with an empty app
    

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30. func perform(with invocation: XCSourceEditorCommandInvocation,
    completionHandler: @escaping (Error?) -> Void) {
    // Actual code of plugin
    }
    

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32. ONLY SINGLE-FILE TEXT BUFFER ACCESS
    

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33. ONLY SINGLE-FILE TEXT BUFFER ACCESS
    ▸
    !
    Does allow at least some sorting, linting, formatting
    

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34. ONLY SINGLE-FILE TEXT BUFFER ACCESS
    ▸
    !
    Does allow at least some sorting, linting, formatting
    ▸
    ☹
    Only ever the current file
    

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35. ONLY SINGLE-FILE TEXT BUFFER ACCESS
    ▸
    !
    Does allow at least some sorting, linting, formatting
    ▸
    ☹
    Only ever the current file
    ▸
    #
    No access to the AST
    

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36. ONLY SINGLE-FILE TEXT BUFFER ACCESS
    ▸
    !
    Does allow at least some sorting, linting, formatting
    ▸
    ☹
    Only ever the current file
    ▸
    #
    No access to the AST
    ▸
    $
    No access to file or project structure
    

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37. ONLY SINGLE-FILE TEXT BUFFER ACCESS
    ▸
    !
    Does allow at least some sorting, linting, formatting
    ▸
    ☹
    Only ever the current file
    ▸
    #
    No access to the AST
    ▸
    $
    No access to file or project structure
    ▸
    $
    No user interface permitted
    

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38. FURTHER INVOCATION LIMITATIONS
    

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39. FURTHER INVOCATION LIMITATIONS
    ▸
    !
    Cannot run in background
    

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40. FURTHER INVOCATION LIMITATIONS
    ▸
    !
    Cannot run in background
    ▸
    "
    Must be actively invoked by the user
    

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41. FURTHER INVOCATION LIMITATIONS
    ▸
    !
    Cannot run in background
    ▸
    "
    Must be actively invoked by the user
    ▸
    #
    No default key binding
    

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47. SWIFT PACKAGE MANAGER
    !
    PLUGINS
    

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52. ✅
    SWIFT 5.6
    

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53. ✅
    SWIFT 5.6
    !
    XCODE 14
    

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54. 1. COMMAND PLUGINS
    2. BUILD TOOL PLUGINS
    

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55. COMMAND PLUGINS
    

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56. CODE FROM "CREATE SWIFT PACKAGE PLUGINS"
    HTTPS://DEVELOPER.APPLE.COM/VIDEOS/PLAY/WWDC2022/110401/
    

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57. COMMAND PLUGINS
    ▸ Can ask permission to write in the package directory
    

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58. // Package.swift
    .plugin(
    name: "GenerateContributors",
    capability: .command(
    intent: .custom(verb: "regenerate-contributors-list",
    description: "Generates the CONTRIBUTORS.txt
    file based on Git logs"),
    permissions: [
    .writeToPackageDirectory(reason: "This command write the
    new CONTRIBUTORS.txt to the source root.")
    ]
    )),
    

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59. // Package.swift
    .plugin(
    name: "GenerateContributors",
    capability: .command(
    intent: .custom(verb: "regenerate-contributors-list",
    description: "Generates the CONTRIBUTORS.txt
    file based on Git logs"),
    permissions: [
    .writeToPackageDirectory(reason: "This command write the
    new CONTRIBUTORS.txt to the source root.")
    ]
    )),
    

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60. COMMAND PLUGINS
    ▸ Can ask permission to write in the package directory
    ▸ Can be invoked at the command line
    

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61. // Get all plugins available on a particular package
    swift package plugin --list
    // Run a specific plugin, in this case GenerateContributors
    swift package regenerate-contributors-list
    

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63. COMMAND PLUGINS
    ▸ Can ask permission to write in the package directory
    ▸ Can be invoked at the command line
    ▸ Can be invoked from a menu item in Xcode
    

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69. COMMAND PLUGINS
    ▸ Can ask permission to write in the package directory
    ▸ Can be invoked at the command line
    ▸ Can be invoked from a menu item Xcode
    ▸ Either way, must be invoked separately from the build process
    

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70. BUILD TOOL PLUGINS
    

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71. BUILD TOOL PLUGINS
    RUN AUTOMATICALLY ON EVERY BUILD
    

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72. BUILD TOOL PLUGINS
    (THE THING I REALLY WANT TO
    USE)
    

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73. THE MORE COMPLICATED BUT LESS COMPLICATED WAY:
    EMBED A PACKAGE
    IN YOUR .XCODEPROJ
    

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74. MORE COMPLICATED
    (YOU HAVE TO ADD A WHOLE SWIFT PACKAGE TO YOUR PROJECT)
    

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75. LESS COMPLICATED
    (IT WORKS WAY MORE RELIABLY)
    

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76. SAMPLE APP
    https://github.com/designatednerd/
    RadioactiveCat
    

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77. via https://energyeducation.ca/encyclopedia/Half_life
    

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81. BUILD TOOL EASY MODE
    BRING IN SOMEONE ELSE'S PLUGIN
    

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82. DO NIL DISTURB
    HTTPS://GITHUB.COM/ICANZILB/
    DONILDISTURBPLUGIN
    

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83. // Package.swift
    .dependencies: [
    .package(url: "https://github.com/icanzilb/
    DoNilDisturbPlugin.git", from: "0.0.5"),
    ]
    

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84. // Package.swift
    .target(
    name: "Cats",
    dependencies: [
    ],
    plugins: [
    .plugin(name: "DoNilDisturbPlugin",
    package: "DoNilDisturbPlugin")
    ]
    ),
    

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86. DO NOT BLINDLY CLICK
    TRUST & ENABLE ALL
    

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92. BUILD TOOL HARD MODE:
    CREATE YOUR OWN PLUGIN
    

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93. DON'T BUILD YOUR PLUGIN
    AND THE PACKAGE YOU'RE TESTING IT AGAINST
    IN THE SAME REPO
    

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94. GITHUB.COM/DESIGNATEDNERD/
    DATEDIMAGEGENERATOR
    

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95. PLUGIN VS. EXECUTABLE
    

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96. // File structure of the Swift Lib
    !
    DatedImageGenerator
    !
    Plugins
    !
    DatedImageGenerator
    "
    DatedImageGenerator.swift
    !
    Sources
    !
    DatedImage
    "
    DatedImage.swift
    "
    ExifDateFormatter.swift
    !
    DatedImageGeneratorExecutable
    "
    DatedImageGeneratorExecutable.swift
    !
    Tests
    !
    DatedImageGeneratorTests
    "
    DatedImageGeneratorExecutable.swift
    "
    Media.xcassets
    

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97. // File structure of the Swift Lib
    !
    DatedImageGenerator
    !
    Plugins
    !
    DatedImageGenerator
    "
    DatedImageGenerator.swift
    !
    Sources
    !
    DatedImage
    "
    DatedImage.swift
    "
    ExifDateFormatter.swift
    !
    DatedImageGeneratorExecutable
    "
    DatedImageGeneratorExecutable.swift
    !
    Tests
    !
    DatedImageGeneratorTests
    "
    DatedImageGeneratorExecutable.swift
    "
    Media.xcassets
    

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98. // File structure of the Swift Lib
    !
    DatedImageGenerator
    !
    Plugins
    !
    DatedImageGenerator
    "
    DatedImageGenerator.swift
    !
    Sources
    !
    DatedImage
    "
    DatedImage.swift
    "
    ExifDateFormatter.swift
    !
    DatedImageGeneratorExecutable
    "
    DatedImageGeneratorExecutable.swift
    !
    Tests
    !
    DatedImageGeneratorTests
    "
    DatedImageGeneratorExecutable.swift
    "
    Media.xcassets
    

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99. // File structure of the Swift Lib
    !
    DatedImageGenerator
    !
    Plugins
    !
    DatedImageGenerator
    "
    DatedImageGenerator.swift
    !
    Sources
    !
    DatedImage
    "
    DatedImage.swift
    "
    ExifDateFormatter.swift
    !
    DatedImageGeneratorExecutable
    "
    DatedImageGeneratorExecutable.swift
    !
    Tests
    !
    DatedImageGeneratorTests
    "
    DatedImageGeneratorExecutable.swift
    "
    Media.xcassets
    

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100. // File structure of the Swift Lib
     !
     DatedImageGenerator
     !
     Plugins
     !
     DatedImageGenerator
     "
     DatedImageGenerator.swift
     !
     Sources
     !
     DatedImage // <-- Exported library used in executable and main app
     "
     DatedImage.swift
     "
     ExifDateFormatter.swift
     !
     DatedImageGeneratorExecutable
     "
     DatedImageGeneratorExecutable.swift
     !
     Tests
     !
     DatedImageGeneratorTests
     "
     DatedImageGeneratorExecutable.swift
     "
     Media.xcassets
     

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101. // File structure of the Swift Lib
     !
     DatedImageGenerator
     !
     Plugins
     !
     DatedImageGenerator
     "
     DatedImageGenerator.swift
     !
     Sources
     !
     DatedImage // <-- Exported Framework used in executable and main app
     "
     DatedImage.swift
     "
     ExifDateFormatter.swift
     !
     DatedImageGeneratorExecutable // <-- The thing that does all the work
     "
     DatedImageGeneratorExecutable.swift
     !
     Tests
     !
     DatedImageGeneratorTests
     "
     DatedImageGeneratorExecutable.swift
     "
     Media.xcassets
     

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102. // File structure of the Swift Lib
     !
     DatedImageGenerator
     !
     Plugins
     !
     DatedImageGenerator
     "
     DatedImageGenerator.swift
     !
     Sources
     !
     DatedImage
     "
     DatedImage.swift
     "
     ExifDateFormatter.swift
     !
     DatedImageGeneratorExecutable
     "
     DatedImageGeneratorExecutable.swift
     !
     Tests
     !
     DatedImageGeneratorTests
     "
     DatedImageGeneratorExecutable.swift
     "
     Media.xcassets
     

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103. // Plugins/DatedImageGenerator.swift
     @main
     struct DatedImageGenerator: BuildToolPlugin {
     func createBuildCommands(context: PluginContext,
     target: Target) async throws -> [Command] {
     // TODO: Create info for build command
     return [
     .buildCommand(
     displayName: "Generate Dated Images",
     executable: try context.tool(named: "DatedImageGeneratorExecutable").path,
     // more to come here
     arguments: "TODO",
     outputFiles: ["TODO"]
     )
     ]
     }
     }
     

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104. WHAT'S IN THE
     EXECUTABLE?
     

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105. // Sources/DatedImageGeneratorExecutable/
     // DatedImageGeneratorExecutable.swift
     @main
     struct DatedImageGeneratorExecutable {
     static func main() throws {
     // How do we get information from the Plugin?
     }
     }
     

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106. // Sources/DatedImageGeneratorExecutable/
     // DatedImageGeneratorExecutable.swift
     @main
     struct DatedImageGeneratorExecutable {
     static func main() throws {
     // Grab the 2nd argument as a string
     ProcessInfo.processInfo.arguments[1]
     }
     }
     

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107. // Sources/DatedImageGeneratorExecutable/
     // DatedImageGeneratorExecutable.swift
     @main
     struct DatedImageGeneratorExecutable {
     static func main() throws {
     // Turn it into Data
     Data(ProcessInfo.processInfo.arguments[1].utf8))
     }
     }
     

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108. // Sources/DatedImageGeneratorExecutable/
     // DatedImageGeneratorExecutable.swift
     @main
     struct DatedImageGeneratorExecutable {
     static func main() throws {
     // Decode it into a codable object!
     let invocation = try JSONDecoder()
     .decode(PluginInvocation.self,
     from: Data(ProcessInfo.processInfo.arguments[1].utf8))
     }
     }
     

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109. "I should just put the codable object in
     the executable and import it into the
     plugin"
     

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113. // One copy of this in the plugin, one in the executable
     struct PluginInvocation: Codable {
     let catalogPaths: [String]
     let outputPath: String
     func encodedString() throws -> String {
     let data = try JSONEncoder().encode(self)
     return String(decoding: data, as: UTF8.self)
     }
     }
     

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114. // One copy of this in the plugin, one in the executable
     // (or share with a common lib)
     struct PluginInvocation: Codable {
     let catalogPaths: [String]
     let outputPath: String
     func encodedString() throws -> String {
     let data = try JSONEncoder().encode(self)
     return String(decoding: data, as: UTF8.self)
     }
     }
     

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115. // Plugins/DatedImageGenerator.swift
     @main
     struct DatedImageGenerator: BuildToolPlugin {
     func createBuildCommands(context: PluginContext,
     target: Target) async throws -> [Command] {
     guard let target = target as? SourceModuleTarget else { throw ImageGenError.notASourceModule }
     let assetCatalogPaths = target.sourceFiles(withSuffix: "xcassets")
     .compactMap { assetCatalog in
     return assetCatalog.path.string
     }
     let outputPath = context.pluginWorkDirectory
     .appending(["DatedImages.swift"])
     let invocation = PluginInvocation(catalogPaths: assetCatalogPaths,
     outputPath: outputPath.string)
     return [
     .buildCommand(
     displayName: "Generate Dated Images",
     executable: try context.tool(named: "DatedImageGeneratorExecutable").path,
     arguments: [try invocation.encodedString()],
     outputFiles: [outputPath]
     )
     ]
     }
     }
     

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116. // Plugins/DatedImageGenerator.swift
     @main
     struct DatedImageGenerator: BuildToolPlugin {
     func createBuildCommands(context: PluginContext,
     target: Target) async throws -> [Command] {
     guard let target = target as? SourceModuleTarget else { throw ImageGenError.notASourceModule }
     let assetCatalogPaths = target.sourceFiles(withSuffix: "xcassets")
     .compactMap { assetCatalog in
     return assetCatalog.path.string
     }
     let outputPath = context.pluginWorkDirectory
     .appending(["DatedImages.swift"])
     let invocation = PluginInvocation(catalogPaths: assetCatalogPaths,
     outputPath: outputPath.string)
     return [
     .buildCommand(
     displayName: "Generate Dated Images",
     executable: try context.tool(named: "DatedImageGeneratorExecutable").path,
     arguments: [try invocation.encodedString()],
     outputFiles: [outputPath]
     )
     ]
     }
     }
     

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117. !
     TARGET
     (TECHNICALLY PACKAGEPLUGIN.TARGET)
     

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118. // Plugins/DatedImageGenerator.swift
     @main
     struct DatedImageGenerator: BuildToolPlugin {
     func createBuildCommands(context: PluginContext,
     target: Target) async throws -> [Command] {
     guard let target = target as? SourceModuleTarget else { throw ImageGenError.notASourceModule }
     let assetCatalogPaths = target.sourceFiles(withSuffix: "xcassets")
     .compactMap { assetCatalog in
     return assetCatalog.path.string
     }
     let outputPath = context.pluginWorkDirectory
     .appending(["DatedImages.swift"])
     let invocation = PluginInvocation(catalogPaths: assetCatalogPaths,
     outputPath: outputPath.string)
     return [
     .buildCommand(
     displayName: "Generate Dated Images",
     executable: try context.tool(named: "DatedImageGeneratorExecutable").path,
     arguments: [try invocation.encodedString()],
     outputFiles: [outputPath]
     )
     ]
     }
     }
     

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119. !
     PLUGIN CONTEXT
     (TECHNICALLY PACKAGEPLUGIN.PLUGINCONTEXT)
     

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120. PLUGINWORKDIRECTORY
     IS YOUR SANDBOX
     

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121. // Plugins/DatedImageGenerator.swift
     @main
     struct DatedImageGenerator: BuildToolPlugin {
     func createBuildCommands(context: PluginContext,
     target: Target) async throws -> [Command] {
     guard let target = target as? SourceModuleTarget else { throw ImageGenError.notASourceModule }
     let assetCatalogPaths = target.sourceFiles(withSuffix: "xcassets")
     .compactMap { assetCatalog in
     return assetCatalog.path.string
     }
     let outputPath = context.pluginWorkDirectory
     .appending(["DatedImages.swift"])
     let invocation = PluginInvocation(catalogPaths: assetCatalogPaths,
     outputPath: outputPath.string)
     return [
     .buildCommand(
     displayName: "Generate Dated Images",
     executable: try context.tool(named: "DatedImageGeneratorExecutable").path,
     arguments: [try invocation.encodedString()],
     outputFiles: [outputPath]
     )
     ]
     }
     }
     

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122. // Plugins/DatedImageGenerator.swift
     @main
     struct DatedImageGenerator: BuildToolPlugin {
     func createBuildCommands(context: PluginContext,
     target: Target) async throws -> [Command] {
     guard let target = target as? SourceModuleTarget else { throw ImageGenError.notASourceModule }
     let assetCatalogPaths = target.sourceFiles(withSuffix: "xcassets")
     .compactMap { assetCatalog in
     return assetCatalog.path.string
     }
     let outputPath = context.pluginWorkDirectory
     .appending(["DatedImages.swift"])
     let invocation = PluginInvocation(catalogPaths: assetCatalogPaths,
     outputPath: outputPath.string)
     return [
     .buildCommand(
     displayName: "Generate Dated Images",
     executable: try context.tool(named: "DatedImageGeneratorExecutable").path,
     arguments: [try invocation.encodedString()],
     outputFiles: [outputPath]
     )
     ]
     }
     }
     

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124. QUICK RECAP OF PLUGIN CREATION
     

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125. QUICK RECAP OF PLUGIN CREATION
     ▸ Create a plugin in Plugins
     

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126. QUICK RECAP OF PLUGIN CREATION
     ▸ Create a plugin in Plugins
     ▸ Create an executable it will call in Sources
     

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127. QUICK RECAP OF PLUGIN CREATION
     ▸ Create a plugin in Plugins
     ▸ Create an executable it will call in Sources
     ▸ Use a codable object to pass data between them
     

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128. QUICK RECAP OF PLUGIN CREATION
     ▸ Create a plugin in Plugins
     ▸ Create an executable it will call in Sources
     ▸ Use a codable object to pass data between them
     ▸ Note that the plugin depends on but cannot import the executable
     

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129. !
     BACK TO THE KITTAHS!
     

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130. // In Cats/Package.swift
     dependencies: [
     .package(url: "https://github.com/designatednerd/
     DatedImageGenerator.git", from: "0.0.1"),
     .package(url: "https://github.com/icanzilb/
     DoNilDisturbPlugin.git", from: "0.0.5"),
     ],
     

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131. // In Cats/Package.swift
     .target(
     name: "Cats",
     dependencies: [
     .product(name: "DatedImage", package: "DatedImageGenerator"),
     ],
     plugins: [
     .plugin(name: "DatedImageGenerator", package: "DatedImageGenerator"),
     .plugin(name: "DoNilDisturbPlugin", package: "DoNilDisturbPlugin")
     ]
     ),
     

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132. // In Cats/Package.swift
     .target(
     name: "Cats",
     dependencies: [
     .product(name: "DatedImage", package: "DatedImageGenerator"),
     ],
     plugins: [
     .plugin(name: "DatedImageGenerator", package: "DatedImageGenerator"),
     .plugin(name: "DoNilDisturbPlugin", package: "DoNilDisturbPlugin")
     ]
     ),
     

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133. // In Cats/Package.swift
     .target(
     name: "Cats",
     dependencies: [
     .product(name: "DatedImage", package: "DatedImageGenerator"),
     ],
     plugins: [
     .plugin(name: "DatedImageGenerator", package: "DatedImageGenerator"),
     .plugin(name: "DoNilDisturbPlugin", package: "DoNilDisturbPlugin")
     ]
     ),
     

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140. WHAT ABOUT RUNNING PLUGINS
     ON AN APP TARGET?
     

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141. XCODE PROJECT PLUGIN
     

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142. XCODE PROJECT PLUGIN
     (A KIND OF BUILD TOOL PLUGIN)
     

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143. #if canImport(XcodeProjectPlugin)
     import XcodeProjectPlugin
     extension DatedImageGenerator: XcodeBuildToolPlugin {
     func createBuildCommands(context: XcodePluginContext,
     target: XcodeTarget) throws -> [Command] {
     let assetCatalogPaths = context.xcodeProject.filePaths
     .filter({ $0.string.hasSuffix("xcassets")})
     .map { $0.string }
     // Rest of the code the same as in the main plugin
     }
     }
     #endif
     

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144. #if canImport(XcodeProjectPlugin)
     import XcodeProjectPlugin
     extension DatedImageGenerator: XcodeBuildToolPlugin {
     func createBuildCommands(context: XcodePluginContext,
     target: XcodeTarget) throws -> [Command] {
     let assetCatalogPaths = context.xcodeProject.filePaths
     .filter({ $0.string.hasSuffix("xcassets")})
     .map { $0.string }
     // Rest of the code the same as in the main plugin
     }
     }
     #endif
     

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145. #if canImport(XcodeProjectPlugin)
     import XcodeProjectPlugin
     extension DatedImageGenerator: XcodeBuildToolPlugin {
     func createBuildCommands(context: XcodePluginContext,
     target: XcodeTarget) throws -> [Command] {
     let assetCatalogPaths = context.xcodeProject.filePaths
     .filter({ $0.string.hasSuffix("xcassets")})
     .map { $0.string }
     // Rest of the code the same as in the main plugin
     }
     }
     #endif
     

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146. #if canImport(XcodeProjectPlugin)
     import XcodeProjectPlugin
     extension DatedImageGenerator: XcodeBuildToolPlugin {
     func createBuildCommands(context: XcodePluginContext,
     target: XcodeTarget) throws -> [Command] {
     let assetCatalogPaths = context.xcodeProject.filePaths
     .filter({ $0.string.hasSuffix("xcassets")})
     .map { $0.string }
     // Rest of the code the same as in the main plugin
     }
     }
     #endif
     

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147. #if canImport(XcodeProjectPlugin)
     import XcodeProjectPlugin
     extension DatedImageGenerator: XcodeBuildToolPlugin {
     func createBuildCommands(context: XcodePluginContext,
     target: XcodeTarget) throws -> [Command] {
     let assetCatalogPaths = context.xcodeProject.filePaths
     .filter({ $0.string.hasSuffix("xcassets")})
     .map { $0.string }
     // Rest of the code the same as in the main plugin
     }
     }
     #endif
     

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148. View Slide

149. View Slide

150. View Slide

151. View Slide

152. View Slide

153. View Slide

154. SPM PLUGIN LIMITATIONS
     

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155. SPM PLUGIN LIMITATIONS
     (that I've found so far)
     

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156. SPM PLUGIN LIMITATIONS
     (that I've found so far)
     ▸ Still no UI for you
     

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157. SPM PLUGIN LIMITATIONS
     (that I've found so far)
     ▸ Still no UI for you
     ▸ You can't even ask to use the network
     

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158. SPM PLUGIN LIMITATIONS
     (that I've found so far)
     ▸ Still no UI for you
     ▸ You can't even ask to use the network
     ▸ You can't share data between plugins
     

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159. SPM PLUGIN LIMITATIONS
     (that I've found so far)
     ▸ Still no UI for you
     ▸ You can't even ask to use the network
     ▸ You can't share data between plugins
     ▸ Can't do anything with build results
     

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160. !
     PLUGIN WISH LIST
     

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161. PLUGIN WISH LIST
     ▸ File metadata
     

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162. PLUGIN WISH LIST
     ▸ File metadata
     ▸ Ability to show UI in Xcode
     

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163. OBLIGATORY SUMMARY SLIDE
     

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164. OBLIGATORY SUMMARY SLIDE
     ▸ Alcatraz
     

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165. OBLIGATORY SUMMARY SLIDE
     ▸ Alcatraz
     ! "
     Xcode 8 Extensions
     

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166. OBLIGATORY SUMMARY SLIDE
     ▸ Alcatraz
     ! "
     Xcode 8 Extensions
     ▸ SPM Plugins to the rescue!
     

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167. OBLIGATORY SUMMARY SLIDE
     ▸ Alcatraz
     ! "
     Xcode 8 Extensions
     ▸ SPM Plugins to the rescue!
     ▸ Command plugins: On demand, Build tool plugins: On every build
     

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168. OBLIGATORY SUMMARY SLIDE
     ▸ Alcatraz
     ! "
     Xcode 8 Extensions
     ▸ SPM Plugins to the rescue!
     ▸ Command plugins: On demand, Build tool plugins: On every build
     ▸ Security: Be super-mindful of which plugins you use
     

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169. OBLIGATORY SUMMARY SLIDE
     ▸ Alcatraz
     ! "
     Xcode 8 Extensions
     ▸ SPM Plugins to the rescue!
     ▸ Command plugins: On demand, Build tool plugins: On every build
     ▸ Security: Be super-mindful of which plugins you use
     ▸ Building plugins is a bit complicated, but also pretty fun
     

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170. THANK YOU!
     

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171. SWIFT-EVOLUTION LINKS!
     ▸ SE-0303: Extensible Build Tools github.com/apple/swift-evolution/
     blob/main/proposals/0303-swiftpm-extensible-build-tools.md
     ▸ SE-0325: Additional Plugin APIs github.com/apple/swift-evolution/
     blob/main/proposals/0325-swiftpm-additional-plugin-apis.md
     ▸ SE-0332: SPM Command Plugins github.com/apple/swift-evolution/
     blob/main/proposals/0332-swiftpm-command-plugins.md
     

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172. !
     SLIGHTLY TERRIFYING LINKS!
     ▸ Xcode Ghost details: en.wikipedia.org/wiki/XcodeGhost
     ▸ Strawhorse leaked document: theintercept.com/document/
     2015/03/10/strawhorse-attacking-macos-ios-software-
     development-kit
     ▸ Strawhorse Context: theintercept.com/2015/03/10/ispy-cia-
     campaign-steal-apples-secrets/
     

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173. !
     PLUGIN LINKS!
     ▸ Do Nil Disturb: github.com/icanzilb/DoNilDisturbPlugin
     ▸ Swift SafeURL: github.com/baguio/SwiftSafeURL
     

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