Fix github issue #15

Some of the storing and adding overloads were missing the argNames
parameter.

Author: xenomachina

src/main/kotlin/ArgParser.kt

@@ -107,13 +107,15 @@ class ArgParser(args: Array<out String>,
     /**
      * Creates a Delegate for a single-argument option that stores and returns the option's argument.
      */
-    fun storing(vararg names: String, help: String): Delegate<String> =
-            storing(*names, help = help) { this }
+    fun storing(vararg names: String, help: String, argName: String? = null): Delegate<String> =
+            storing(*names, help = help, argName = argName) { this }
 
     /**
      * Creates a DelegateProvider for a single-argument option that stores and returns the option's argument.
      */
-    fun storing(help: String) = DelegateProvider { identifier -> storing(identifierToOptionName(identifier), help = help) }
+    fun storing(help: String, argName: String? = null) =
+            DelegateProvider { identifier ->
+                storing(identifierToOptionName(identifier), help = help, argName = argName) }
 
     /**
      * Creates a Delegate for a single-argument option that adds the option's (transformed) argument to a
@@ -167,16 +169,17 @@ class ArgParser(args: Array<out String>,
      */
     fun <T> adding(
             help: String,
+            argName: String? = null,
             transform: String.() -> T
     ) = DelegateProvider { identifier ->
-        adding(identifierToOptionName(identifier), help = help, transform = transform) }
+        adding(identifierToOptionName(identifier), help = help, argName = argName, transform = transform) }
 
     /**
      * Creates a Delegate for a single-argument option that adds the option's argument to a MutableList each time the
      * option appears in args, and returns said MutableCollection.
      */
-    fun adding(vararg names: String, help: String): Delegate<MutableList<String>> =
-            adding(*names, help = help) { this }
+    fun adding(vararg names: String, help: String, argName: String? = null): Delegate<MutableList<String>> =
+            adding(*names, help = help, argName = argName) { this }
 
     /**
      * Creates a DelegateProvider for a single-argument option that adds the option's argument to a MutableList each time the

src/test/kotlin/ArgParserTest.kt

@@ -1418,3 +1418,33 @@ class PositionalListAddValidatorTest : Test({
         message shouldBe "X elements must be even, 37 is odd"
     }
 })
+
+class Issue15Test : Test({
+    class Args(parser: ArgParser) {
+        val manual by parser.storing("--named-by-hand", help = TEST_HELP, argName = "HANDYS-ARG")
+        val auto by parser.storing(TEST_HELP, argName = "OTTOS-ARG")
+        val foo by parser.adding(help = TEST_HELP, argName = "BAR") { toInt() }
+        val bar by parser.adding("--baz", help = TEST_HELP, argName = "QUUX")
+    }
+
+    shouldThrow<ShowHelpException> {
+        Args(parserOf("--help")).manual
+    }.run {
+        // TODO: find a way to make this less brittle (ie: don't use help text)
+        StringWriter().apply { printUserMessage(this, null, 10000) }.toString().trim() shouldBe """
+usage: [-h] --named-by-hand HANDYS-ARG --auto OTTOS-ARG [--foo BAR]... [--baz QUUX]...
+
+required arguments:
+  --named-by-hand HANDYS-ARG   test help message
+
+  --auto OTTOS-ARG             test help message
+
+
+optional arguments:
+  -h, --help                   show this help message and exit
+
+  --foo BAR                    test help message
+
+  --baz QUUX                   test help message""".trim()
+    }
+})