Replace Commander with ArgumentParser in swift-doc target

Package.swift

@@ -11,13 +11,14 @@ let package = Package(
         .package(url: "https://github.com/SwiftDocOrg/SwiftSemantics.git", .branch("swift-5.2")),
         .package(url: "https://github.com/apple/swift-syntax.git", .revision("swift-5.2-DEVELOPMENT-SNAPSHOT-2020-02-12-a")),
         .package(url: "https://github.com/kylef/Commander.git", .upToNextMinor(from: "0.9.1")),
+        .package(url: "https://github.com/apple/swift-argument-parser", .upToNextMinor(from: "0.0.2")),
     ],
     targets: [
         // Targets are the basic building blocks of a package. A target can define a module or a test suite.
         // Targets can depend on other targets in this package, and on products in packages which this package depends on.
         .target(
             name: "swift-doc",
-            dependencies: ["SwiftDoc", "SwiftSemantics", "SwiftMarkup", "CommonMarkBuilder", "Commander"]
+            dependencies: ["SwiftDoc", "SwiftSemantics", "SwiftMarkup", "CommonMarkBuilder", "ArgumentParser"]
         ),
         .target(
             name: "swift-dcov",

Sources/swift-doc/Subcommands/Generate.swift

@@ -0,0 +1,64 @@
+import ArgumentParser
+import Foundation
+import SwiftSemantics
+import struct SwiftSemantics.Protocol
+import SwiftMarkup
+import SwiftDoc
+
+extension SwiftDoc {
+    struct Generate: ParsableCommand {
+        struct Options: ParsableArguments {
+            @Argument(help: "One or more paths to Swift files")
+            var inputs: [String]
+
+            @Option(name: .shortAndLong,
+                    default: ".build/documentation",
+                    help: "The path for generated output")
+            var output: String
+        }
+
+        static var configuration = CommandConfiguration(abstract: "Generates Swift documentation")
+
+        @OptionGroup()
+        var options: Options
+
+        func run() throws {
+            let module = try Module(paths: options.inputs)
+
+            let outputDirectoryURL = URL(fileURLWithPath: options.output)
+            try fileManager.createDirectory(at: outputDirectoryURL, withIntermediateDirectories: true, attributes: fileAttributes)
+
+            do {
+                try HomePage(module: module).write(to: outputDirectoryURL.appendingPathComponent("Home.md"))
+                try SidebarPage(module: module).write(to: outputDirectoryURL.appendingPathComponent("_Sidebar.md"))
+                try FooterPage().write(to: outputDirectoryURL.appendingPathComponent("_Footer.md"))
+
+                var globals: [String: [Symbol]] = [:]
+                for symbol in module.topLevelSymbols.filter({ $0.isPublic }) {
+                    switch symbol.declaration {
+                    case is Class:
+                        try TypePage(module: module, symbol: symbol).write(to: outputDirectoryURL.appendingPathComponent("\(path(for: symbol.id.description)).md"))
+                    case is Enumeration:
+                        try TypePage(module: module, symbol: symbol).write(to: outputDirectoryURL.appendingPathComponent("\(path(for: symbol.id.description)).md"))
+                    case is Structure:
+                        try TypePage(module: module, symbol: symbol).write(to: outputDirectoryURL.appendingPathComponent("\(path(for: symbol.id.description)).md"))
+                    case let `protocol` as Protocol:
+                        try TypePage(module: module, symbol: symbol).write(to: outputDirectoryURL.appendingPathComponent("\(path(for: `protocol`.name)).md"))
+                    case let `typealias` as Typealias:
+                        try TypealiasPage(module: module, symbol: symbol).write(to: outputDirectoryURL.appendingPathComponent("\(path(for: `typealias`.name)).md"))
+                    case let function as Function where !function.isOperator:
+                        globals[function.name, default: []] += [symbol]
+                    case let variable as Variable:
+                        globals[variable.name, default: []] += [symbol]
+                    default:
+                        continue
+                    }
+                }
+
+                for (name, symbols) in globals {
+                    try GlobalPage(module: module, name: name, symbols: symbols).write(to: outputDirectoryURL.appendingPathComponent("\(path(for: name)).md"))
+                }
+            }
+        }
+    }
+}

Sources/swift-doc/main.swift

@@ -1,65 +1,18 @@
-import Commander
+import ArgumentParser
 import Foundation
-import SwiftSemantics
-import struct SwiftSemantics.Protocol
-import SwiftMarkup
-import SwiftDoc
-
-let arguments = Array(ProcessInfo.processInfo.arguments.dropFirst())
 
 let fileManager = FileManager.default
 let fileAttributes: [FileAttributeKey : Any] = [.posixPermissions: 0o744]
 
 var standardOutput = FileHandle.standardOutput
 var standardError = FileHandle.standardError
 
-command(
-    Option<String>("output", default: ".build/documentation", description: "The path for generated output"),
-    Argument<[String]>("inputs", description: "One or more paths to Swift files", validator: { (inputs) -> [String] in
-        inputs.filter { path in
-            var isDirectory: ObjCBool = false
-            return fileManager.fileExists(atPath: path, isDirectory: &isDirectory) || isDirectory.boolValue
-        }
-    }), { output, inputs in
-        do {
-            let module = try Module(paths: inputs)
-
-            let outputDirectoryURL = URL(fileURLWithPath: output)
-            try fileManager.createDirectory(at: outputDirectoryURL, withIntermediateDirectories: true, attributes: fileAttributes)
-
-            do {
-                try HomePage(module: module).write(to: outputDirectoryURL.appendingPathComponent("Home.md"))
-                try SidebarPage(module: module).write(to: outputDirectoryURL.appendingPathComponent("_Sidebar.md"))
-                try FooterPage().write(to: outputDirectoryURL.appendingPathComponent("_Footer.md"))
-
-                var globals: [String: [Symbol]] = [:]
-                for symbol in module.topLevelSymbols.filter({ $0.isPublic }) {
-                    switch symbol.declaration {
-                    case is Class:
-                        try TypePage(module: module, symbol: symbol).write(to: outputDirectoryURL.appendingPathComponent("\(path(for: symbol.id.description)).md"))
-                    case is Enumeration:
-                        try TypePage(module: module, symbol: symbol).write(to: outputDirectoryURL.appendingPathComponent("\(path(for: symbol.id.description)).md"))
-                    case is Structure:
-                        try TypePage(module: module, symbol: symbol).write(to: outputDirectoryURL.appendingPathComponent("\(path(for: symbol.id.description)).md"))
-                    case let `protocol` as Protocol:
-                        try TypePage(module: module, symbol: symbol).write(to: outputDirectoryURL.appendingPathComponent("\(path(for: `protocol`.name)).md"))
-                    case let `typealias` as Typealias:
-                        try TypealiasPage(module: module, symbol: symbol).write(to: outputDirectoryURL.appendingPathComponent("\(path(for: `typealias`.name)).md"))
-                    case let function as Function where !function.isOperator:
-                        globals[function.name, default: []] += [symbol]
-                    case let variable as Variable:
-                        globals[variable.name, default: []] += [symbol]
-                    default:
-                        continue
-                    }
-                }
+struct SwiftDoc: ParsableCommand {
+    static var configuration = CommandConfiguration(
+        abstract: "A utility for generating documentation for Swift code.",
+        subcommands: [Generate.self],
+        defaultSubcommand: Generate.self
+    )
+}
 
-                for (name, symbols) in globals {
-                    try GlobalPage(module: module, name: name, symbols: symbols).write(to: outputDirectoryURL.appendingPathComponent("\(path(for: name)).md"))
-                }
-            }
-        } catch {
-            print("Error: \(error)", to: &standardError)
-            exit(EXIT_FAILURE)
-        }
-}).run()
+SwiftDoc.main()