From edf96d712fd3d781134eabc7eba49729201a8058 Mon Sep 17 00:00:00 2001
From: ibrahim oktay <ibrahim.oktay@aktifbank.com.tr>
Date: Sat, 23 May 2020 21:15:54 +0300
Subject: [PATCH] =?UTF-8?q?Fix=20showing=20help=20message=20when=20?=
 =?UTF-8?q?=E2=80=9C-h=E2=80=9D=20is=20given=20as=20an=20input=20for=20an?=
 =?UTF-8?q?=20array=20type=20argument=20(#149)?=
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When argument is an array and no input is given but “-h”, if you throw an Error in Validate function, it prints error and short usage instead of help message.
This patch checks built-in flags before throwing a validation error.

Solves #149
---
 .../Parsing/CommandParser.swift               |  1 +
 .../HelpGenerationTests.swift                 | 23 +++++++++++++++++++
 2 files changed, 24 insertions(+)

diff --git a/Sources/ArgumentParser/Parsing/CommandParser.swift b/Sources/ArgumentParser/Parsing/CommandParser.swift
index d7642c89b..4ccf02b7e 100644
--- a/Sources/ArgumentParser/Parsing/CommandParser.swift
+++ b/Sources/ArgumentParser/Parsing/CommandParser.swift
@@ -159,6 +159,7 @@ extension CommandParser {
       do {
         try parsedCommand.validate()
       } catch {
+        try checkForBuiltInFlags(split)
         throw CommandError(commandStack: commandStack, parserError: ParserError.userValidationError(error))
       }
 
diff --git a/Tests/ArgumentParserUnitTests/HelpGenerationTests.swift b/Tests/ArgumentParserUnitTests/HelpGenerationTests.swift
index 122ddea04..be1e583bc 100644
--- a/Tests/ArgumentParserUnitTests/HelpGenerationTests.swift
+++ b/Tests/ArgumentParserUnitTests/HelpGenerationTests.swift
@@ -317,4 +317,27 @@ extension HelpGenerationTests {
     """)
   }
 
+  struct K: ParsableCommand {
+    @Argument(help: "A list of paths.")
+    var paths: [String]
+    
+    func validate() throws {
+      if paths.isEmpty {
+        throw ValidationError("At least one path must be specified.")
+      }
+    }
+  }
+  
+  func testHelpWithNoValueForArray() {
+    AssertHelp(for: K.self, equals: """
+    USAGE: k [<paths> ...]
+
+    ARGUMENTS:
+      <paths>                 A list of paths.
+
+    OPTIONS:
+      -h, --help              Show help information.
+
+    """)
+  }
 }