Exclude supercommands from help (#300)

* Ability to exclude super commands from --help

Author: miggs597

Sources/ArgumentParser/Parsable Types/ParsableCommand.swift

@@ -40,7 +40,7 @@ extension ParsableCommand {
   public static var configuration: CommandConfiguration {
     CommandConfiguration()
   }
-  
+
   public mutating func run() throws {
     throw CleanExit.helpRequest(self)
   }

Sources/ArgumentParser/Usage/HelpGenerator.swift

@@ -144,63 +144,65 @@ internal struct HelpGenerator {
     var optionElements: [Section.Element] = []
     /// Used to keep track of elements already seen from parent commands.
     var alreadySeenElements = Set<Section.Element>()
-
-    for commandType in commandStack {
-      let args = Array(ArgumentSet(commandType))
+    
+    guard let commandType = commandStack.last else {
+      return []
+    }
+    
+    let args = Array(ArgumentSet(commandType))
+    
+    var i = 0
+    while i < args.count {
+      defer { i += 1 }
+      let arg = args[i]
 
-      var i = 0
-      while i < args.count {
-        defer { i += 1 }
-        let arg = args[i]
-        
-        guard arg.help.help?.shouldDisplay != false else { continue }
-        
-        let synopsis: String
-        let description: String
-        
-        if args[i].help.isComposite {
-          // If this argument is composite, we have a group of arguments to
-          // output together.
-          var groupedArgs = [arg]
-          let defaultValue = arg.help.defaultValue.map { "(default: \($0))" } ?? ""
-          while i < args.count - 1 && args[i + 1].help.keys == arg.help.keys {
-            groupedArgs.append(args[i + 1])
-            i += 1
-          }
+      guard arg.help.help?.shouldDisplay != false else { continue }
+      
+      let synopsis: String
+      let description: String
+      
+      if args[i].help.isComposite {
+        // If this argument is composite, we have a group of arguments to
+        // output together.
+        var groupedArgs = [arg]
+        let defaultValue = arg.help.defaultValue.map { "(default: \($0))" } ?? ""
+        while i < args.count - 1 && args[i + 1].help.keys == arg.help.keys {
+          groupedArgs.append(args[i + 1])
+          i += 1
+        }
 
-          var synopsisString = ""
-          for arg in groupedArgs {
-            if !synopsisString.isEmpty { synopsisString.append("/") }
-            synopsisString.append("\(arg.synopsisForHelp ?? "")")
-          }
-          synopsis = synopsisString
+        var synopsisString = ""
+        for arg in groupedArgs {
+          if !synopsisString.isEmpty { synopsisString.append("/") }
+          synopsisString.append("\(arg.synopsisForHelp ?? "")")
+        }
+        synopsis = synopsisString
 
-          var descriptionString: String?
-          for arg in groupedArgs {
-            if let desc = arg.help.help?.abstract {
-              descriptionString = desc
-              break
-            }
+        var descriptionString: String?
+        for arg in groupedArgs {
+          if let desc = arg.help.help?.abstract {
+            descriptionString = desc
+            break
           }
-          description = [descriptionString, defaultValue]
-            .compactMap { $0 }
-            .joined(separator: " ")
-        } else {
-          let defaultValue = arg.help.defaultValue.flatMap { $0.isEmpty ? nil : "(default: \($0))" } ?? ""
-          synopsis = arg.synopsisForHelp ?? ""
-          description = [arg.help.help?.abstract, defaultValue]
-            .compactMap { $0 }
-            .joined(separator: " ")
         }
-        
-        let element = Section.Element(label: synopsis, abstract: description, discussion: arg.help.help?.discussion ?? "")
-        if !alreadySeenElements.contains(element) {
-          alreadySeenElements.insert(element)
-          if case .positional = arg.kind {
-            positionalElements.append(element)
-          } else {
-            optionElements.append(element)
-          }
+        description = [descriptionString, defaultValue]
+          .compactMap { $0 }
+          .joined(separator: " ")
+      } else {
+        let defaultValue = arg.help.defaultValue.flatMap { $0.isEmpty ? nil : "(default: \($0))" } ?? ""
+        synopsis = arg.synopsisForHelp ?? ""
+        description = [arg.help.help?.abstract, defaultValue]
+          .compactMap { $0 }
+          .joined(separator: " ")
+      }
+      
+      let element = Section.Element(label: synopsis, abstract: description, discussion: arg.help.help?.discussion ?? "")
+      if !alreadySeenElements.contains(element) {
+        alreadySeenElements.insert(element)
+        if case .positional = arg.kind {
+          positionalElements.append(element)
+        } else {
+          optionElements.append(element)
         }
       }
     }

Tests/ArgumentParserUnitTests/HelpGenerationTests.swift

@@ -431,4 +431,46 @@ extension HelpGenerationTests {
 
     """)
   }
+    
+  struct Foo: ParsableCommand {
+    public static var configuration = CommandConfiguration(
+      commandName: "foo",
+      abstract: "Perform some foo",
+      subcommands: [
+        Bar.self
+      ],
+      helpNames: [.short, .long, .customLong("help", withSingleDash: true)])
+        
+    @Option(help: "Name for foo")
+    var fooName: String?
+        
+    public init() {}
+  }
+
+  struct Bar: ParsableCommand {
+    static let configuration = CommandConfiguration(
+      commandName: "bar",
+      _superCommandName: "foo",
+      abstract: "Perform bar operations",
+      helpNames: [.short, .long, .customLong("help", withSingleDash: true)])
+            
+    @Option(help: "Bar Strength")
+    var barStrength: String?
+        
+    public init() {}
+  }
+
+  func testHelpExcludingSuperCommand() throws {
+    AssertHelp(for: Bar.self, root: Foo.self, equals: """
+    OVERVIEW: Perform bar operations
+
+    USAGE: foo bar [--bar-strength <bar-strength>]
+
+    OPTIONS:
+      --bar-strength <bar-strength>
+                              Bar Strength
+      -help, -h, --help       Show help information.
+    
+    """)
+  }
 }