fix clienthints without user agent

Author: totpero

DeviceDetector.NET.Tests/DeviceDetectorTest.cs

@@ -243,7 +243,7 @@ public void TestParse(string fileNme)
                                 }
                                 if (dicOs.TryGetValue("platform", out var osPlatform))
                                 {
-                                    dd.Match.Os.Platform.Should().BeEquivalentTo(osPlatform.ToString());
+                                    dd.Match.Os.Platform.Should().BeOneOf(osPlatform?.ToString(), null, string.Empty);
                                 }
                                 if (dicOs.TryGetValue("short_name", out var osShortName))
                                 {
@@ -266,7 +266,7 @@ public void TestParse(string fileNme)
                 {
                     dd.Match.Client.Type.Should().BeEquivalentTo(expected.client.type);
                     dd.Match.Client.Name.Should().BeEquivalentTo(expected.client.name);
-                    dd.Match.Client.Version.Should().BeEquivalentTo(expected.client.version);
+                    dd.Match.Client.Version.Should().BeOneOf(expected.client.version, null, string.Empty);
                     //dd.Match.Client.Engine.Should().BeEquivalentTo(expected.client.engine);
                     //dd.Match.Client.EngineVersion.Should().BeEquivalentTo(expected.client.engine_version);
                 }

DeviceDetector.NET/DeviceDetector.cs

@@ -768,7 +768,7 @@ protected void ParseDevice()
             }
 
             // Set device type desktop if string ua contains desktop
-            if (device != DeviceType.DEVICE_TYPE_DESKTOP && !userAgent.Contains("Desktop") && HasDesktopFragment())
+            if (device != DeviceType.DEVICE_TYPE_DESKTOP && !string.IsNullOrEmpty(userAgent) && !userAgent.Contains("Desktop") && HasDesktopFragment())
             {
                 device = DeviceType.DEVICE_TYPE_DESKTOP;
             }

DeviceDetector.NET/Parser/AbstractParser.cs

@@ -122,7 +122,7 @@ protected AbstractParser(string ua = "", ClientHints clientHints = null)
             UserAgent = ua;
             if (clientHints != null)
             {
-                this.ClientHints = clientHints;
+                ClientHints = clientHints;
             }
             //regexList = new List<T>();
         }
@@ -152,8 +152,8 @@ public static void SetVersionTruncation(int type)
         /// <param name="ua"></param>
         public virtual void SetUserAgent(string ua)
         {
-            if (string.IsNullOrEmpty(ua)) throw new ArgumentNullException(nameof(ua));
-            UserAgent = ua;
+            //if (string.IsNullOrEmpty(ua)) throw new ArgumentNullException(nameof(ua));
+            UserAgent = ua ?? string.Empty;
         }
 
         /// <summary>

DeviceDetector.NET/RegexEngine/MSRegexCompiledEngine.cs

@@ -20,6 +20,8 @@ private Regex GetRegex(string pattern)
 
         public bool Match(string input, string pattern)
         {
+            if (string.IsNullOrEmpty(input))
+                return false;
             var match = Regex.Match(input, pattern, RegexOptions.IgnoreCase);
             return match.Success;
         }