Merge branch 'master' of https://github.com/object/json-ld.net into iri-fix

# Conflicts:
#	src/JsonLD/Core/JsonLdProcessor.cs
#	src/JsonLD/Core/JsonLdUtils.cs

Author: tpluscode

src/JsonLD/Core/JsonLdProcessor.cs

@@ -66,8 +66,25 @@ public static JArray Expand(JToken input, JsonLdOptions opts)
         {
             // 1)
             // TODO: look into java futures/promises
-            // 2) TODO: better verification of DOMString IRI
-            if (input.Type == JTokenType.String && ((string)input).Contains(":"))
+
+            // 2) verification of DOMString IRI
+            bool isIriString = input.Type == JTokenType.String;
+            if (isIriString)
+            {
+                bool hasColon = false;
+                foreach (var c in ((string) input))
+                {
+                    if (c == ':')
+                        hasColon = true;
+                    if (!hasColon && (c == '{' || c == '['))
+                    {
+                        isIriString = false;
+                        break;
+                    }
+                }
+            }
+
+            if (isIriString)
             {
                 try
                 {

src/JsonLD/Core/JsonLdUtils.cs

@@ -199,7 +199,7 @@ internal static void MergeCompactedValue(JObject obj, string
         public static bool IsAbsoluteIri(string value)
         {
             // TODO: this is a bit simplistic!
-            return value.Contains(":");
+            return value != null && value.Contains(":");
         }
 
         /// <summary>Returns true if the given value is a subject with properties.</summary>

src/JsonLD/Util/JavaCompat.cs

@@ -67,7 +67,7 @@ public static bool SafeCompare<T>(this JToken token, T val)
         {
             try
             {
-                return token.Value<T>().Equals(val);
+                return token == null ? val == null : token.Value<T>().Equals(val);
             }
             catch
             {