Make commands failable

Author: kylef

Commander.playground/Contents.swift

@@ -10,6 +10,6 @@ let group = Group {
   }
 }
 
-group.run([])
-group.run(["login", "kyle"])
-group.run(["logout"])
+try group.run([])
+try group.run(["login", "kyle"])
+try group.run(["logout"])

Commander/CommandType.swift

@@ -1,20 +1,20 @@
 /// Represents a command that can be run, given an argument parser
 public protocol CommandType {
-  func run(parser:ArgumentParser)
+  func run(parser:ArgumentParser) throws
 }
 
 
 /// Extensions to CommandType to provide convinience running methods
 extension CommandType {
   /// Run the command with an array of arguments
-  public func run(arguments:[String]) {
-    run(ArgumentParser(arguments: arguments))
+  public func run(arguments:[String]) throws {
+    try run(ArgumentParser(arguments: arguments))
   }
 
   /// Run the command using the `Process.argument`, removing the executable name
-  public func run() {
+  public func run() throws {
     let parser = ArgumentParser(arguments: Process.arguments)
     parser.shift()  // Executable Name
-    run(parser)
+    try run(parser)
   }
 }

Commander/Group.swift

@@ -11,10 +11,10 @@ public class Group : CommandType {
   }
 
   /// Run the group command
-  public func run(parser:ArgumentParser) {
+  public func run(parser:ArgumentParser) throws {
     if let name = parser.shift() {
       if let command = commands[name] {
-        command.run(parser)
+        try command.run(parser)
       }
     }
   }

CommanderTests/CommandTests.swift

@@ -7,7 +7,7 @@ class CommandTests : XCTestCase {
     let parser = ArgumentParser(arguments: [])
     var didRun = false
 
-    command {
+    try! command {
       didRun = true
     }.run(parser)
 
@@ -18,7 +18,7 @@ class CommandTests : XCTestCase {
     let parser = ArgumentParser(arguments: ["Kyle", "Fuller"])
     var ranName:String? = nil
 
-    command { (name:String) in
+    try! command { (name:String) in
       ranName = name
     }.run(parser)
 

CommanderTests/CommandTypeTests.swift

@@ -6,7 +6,7 @@ class CommandTypeTests : XCTestCase {
   func testRunWithArgumentsArray() {
     var firstArgument:String? = nil
 
-    command { (parser:ArgumentParser) in
+    try! command { (parser:ArgumentParser) in
       firstArgument = parser.shift()
     }.run(["test"])
 

CommanderTests/GroupTests.swift

@@ -13,10 +13,10 @@ class GroupTests : XCTestCase {
 
     XCTAssertFalse(didRunHelpCommand)
 
-    group.run(["unknown"])
+    try! group.run(["unknown"])
     XCTAssertFalse(didRunHelpCommand)
 
-    group.run(["help"])
+    try! group.run(["help"])
     XCTAssertTrue(didRunHelpCommand)
   }
 
@@ -31,17 +31,17 @@ class GroupTests : XCTestCase {
       })
     }
 
-    group.run(["unknown"])
+    try! group.run(["unknown"])
     XCTAssertFalse(didRunHelpCommand)
 
-    group.run(["help"])
+    try! group.run(["help"])
     XCTAssertTrue(didRunHelpCommand)
   }
 
   func testSubGroup() {
     var didRun = false
 
-    Group {
+    try! Group {
       $0.group("group") {
         $0.command("test") {
           didRun = true
@@ -55,19 +55,19 @@ class GroupTests : XCTestCase {
   func testSubCommand() {
     var didRun = false
 
-    Group {
+    try! Group {
       $0.command("test") {
         didRun = true
       }
-      }.run(["test"])
+    }.run(["test"])
 
     XCTAssertTrue(didRun)
   }
 
   func testSubCommandWithArgument() {
     var givenName:String? = nil
 
-    Group {
+    try! Group {
       $0.command("test") { (name:String) in
         givenName = name
       }