From 4c84e686d0351bc86c396c543ac4bd13fcbd8a18 Mon Sep 17 00:00:00 2001
From: Mihai Codoban <micodoba@microsoft.com>
Date: Wed, 30 Mar 2016 18:22:35 -0700
Subject: [PATCH] Avoid duplicate messages

---
 .../ProjectContextBuilder.cs                              | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/Microsoft.DotNet.ProjectModel/ProjectContextBuilder.cs b/src/Microsoft.DotNet.ProjectModel/ProjectContextBuilder.cs
index e3315dafe..4548a0ad4 100644
--- a/src/Microsoft.DotNet.ProjectModel/ProjectContextBuilder.cs
+++ b/src/Microsoft.DotNet.ProjectModel/ProjectContextBuilder.cs
@@ -300,13 +300,19 @@ namespace Microsoft.DotNet.ProjectModel
         private static string ComposeMessageFromInnerExceptions(Exception exception)
         {
             var sb = new StringBuilder();
+            var messages = new HashSet<string>();
 
             while (exception != null)
             {
-                sb.AppendLine(exception.Message);
+                messages.Add(exception.Message);
                 exception = exception.InnerException;
             }
 
+            foreach (var message in messages)
+            {
+                sb.AppendLine(message);
+            }
+
             return sb.ToString();
         }