From f3a6b7ea2a04ddd3d818f7867157acef825b289b Mon Sep 17 00:00:00 2001
From: Jacek Marek <jaccus@gmail.com>
Date: Thu, 18 Sep 2014 00:06:04 +0200
Subject: [PATCH] Make BuildSignature() throw a descriptive message

When global user.name or user.email is set to an empty value, it will
now throw a LibGit2SharpException with proper explanatory message.
Previously it would throw an ArgumentException with obscure message:
"String cannot be empty\nParameter name: name".
---
 LibGit2Sharp/Configuration.cs | 25 ++++++++++++++++++-------
 1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/LibGit2Sharp/Configuration.cs b/LibGit2Sharp/Configuration.cs
index f70442245..9e0a2633d 100644
--- a/LibGit2Sharp/Configuration.cs
+++ b/LibGit2Sharp/Configuration.cs
@@ -344,16 +344,27 @@ internal Signature BuildSignature(DateTimeOffset now, bool shouldThrowIfNotFound
             var name = Get<string>("user.name");
             var email = Get<string>("user.email");
 
-            if (shouldThrowIfNotFound && ((name == null) || (email == null)))
+            if (shouldThrowIfNotFound)
             {
-                throw new LibGit2SharpException("Can not find Name or Email setting of the current user in Git configuration.");
+                if (name == null || string.IsNullOrEmpty(name.Value))
+                {
+                    throw new LibGit2SharpException(
+                        "Can not find Name setting of the current user in Git configuration.");
+                }
+
+                if (email == null || string.IsNullOrEmpty(email.Value))
+                {
+                    throw new LibGit2SharpException(
+                        "Can not find Email setting of the current user in Git configuration.");
+                }
             }
 
-            return new Signature(
-                name != null ? name.Value : "unknown",
-                email != null ? email.Value : string.Format(
-                        CultureInfo.InvariantCulture, "{0}@{1}", Environment.UserName, Environment.UserDomainName),
-                now);
+            var nameForSignature = name == null || string.IsNullOrEmpty(name.Value) ? "unknown" : name.Value;
+            var emailForSignature = email == null || string.IsNullOrEmpty(email.Value)
+                                        ? string.Format("{0}@{1}", Environment.UserName, Environment.UserDomainName)
+                                        : email.Value;
+
+            return new Signature(nameForSignature, emailForSignature, now);
         }
 
         private ConfigurationSafeHandle Snapshot()