Fix: documentation and add unit test issue 294 (#300)

* Fix: documentation and add unit test issue 294

* Fix: the issue 294 bug

* Update securitycodescan.yml

.github/workflows/securitycodescan.yml

@@ -16,7 +16,10 @@ on:
     branches: [ "master" ]
   schedule:
     - cron: '35 15 * * 1'
-
+
+env:
+  DOTNET_ROLL_FORWARD: Major
+
 jobs:
   SCS:
     runs-on: windows-latest

src/System.Net.IPNetwork/IPNetwork2.cs

@@ -624,6 +624,17 @@ private static void InternalParse(bool tryParse, string network, ICidrGuess cidr
             string[] args = network.Split(new char[] { ' ', '/' }, splitOptions);
             byte cidr = 0;
 
+            if (args.Length == 0)
+            {
+                if (tryParse == false)
+                {
+                    throw new ArgumentNullException("network");
+                }
+
+                ipnetwork = null;
+                return;
+            }
+
             if (args.Length == 1)
             {
                 string cidrlessNetwork = args[0];

src/System.Net.IPNetwork/IPNetworkCollection.cs

@@ -8,6 +8,9 @@ namespace System.Net
     using System.Collections.Generic;
     using System.Numerics;
 
+    /// <summary>
+    /// A collection of IPNetwork2
+    /// </summary>
     public class IPNetworkCollection : IEnumerable<IPNetwork2>, IEnumerator<IPNetwork2>
     {
         private BigInteger _enumerator;
@@ -59,6 +62,9 @@ private BigInteger _network
 
         #region Count, Array, Enumerator
 
+        /// <summary>
+        /// Count the nnumber of IPAddresses in a IPNetworkCollection
+        /// </summary>
         public BigInteger Count
         {
             get
@@ -102,6 +108,9 @@ IEnumerator IEnumerable.GetEnumerator()
 
         #region IEnumerator<IPNetwork> Members
 
+        /// <summary>
+        /// Gets the current IEnumerator item
+        /// </summary>
         public IPNetwork2 Current
         {
             get { return this[this._enumerator]; }
@@ -111,6 +120,9 @@ public IPNetwork2 Current
 
         #region IDisposable Members
 
+        /// <summary>
+        /// Dispose the IPNetwork instance
+        /// </summary>
         public void Dispose()
         {
             // nothing to dispose
@@ -120,12 +132,18 @@ public void Dispose()
         #endregion
 
         #region IEnumerator Members
-
+        /// <summary>
+        /// Gets the element in the collection at the current position of the enumerator.
+        /// </summary>
         object IEnumerator.Current
         {
             get { return this.Current; }
         }
 
+        /// <summary>
+        /// Advances the enumerator to the next element of the collection.
+        /// </summary>
+        /// <returns>true if the enumerator was successfully advanced to the next element; false if the enumerator has passed the end of the collection.</returns>
         public bool MoveNext()
         {
             this._enumerator++;
@@ -137,6 +155,9 @@ public bool MoveNext()
             return true;
         }
 
+        /// <summary>
+        /// Sets the enumerator to its initial position, which is before the first element in the collection.
+        /// </summary>
         public void Reset()
         {
             this._enumerator = -1;

src/TestProject/TryParseUnitTest.cs

@@ -333,5 +333,15 @@ public void Test_IPAddress_TryParse(string ipaddress, bool parsed)
         }
 
         #endregion
+
+        #region Issue294
+
+        [TestMethod]
+        public void Test_IPNetwork_TryParse_Issue294()
+        {
+            bool result = IPNetwork2.TryParse("*", out IPNetwork2 ipaddress1);
+            Assert.AreEqual(false, result, "parsed1");
+        }
+        #endregion
     }
 }