Add ContainsWritable tests

SabreTools.DatFiles.Test/DatFileTests.cs

@@ -1514,7 +1514,35 @@ namespace SabreTools.DatFiles.Test
 
         #region ContainsWritable
 
-        // TODO: Write ContainsWritable tests
+        [Fact]
+        public void ContainsWritable_Empty_True()
+        {
+            List<DatItem> datItems = [];
+            DatFile datFile = new Formats.Logiqx(null, deprecated: false);
+
+            bool actual = datFile.ContainsWritable(datItems);
+            Assert.True(actual);
+        }
+
+        [Fact]
+        public void ContainsWritable_NoWritable_False()
+        {
+            List<DatItem> datItems = [new Blank()];
+            DatFile datFile = new Formats.Logiqx(null, deprecated: false);
+
+            bool actual = datFile.ContainsWritable(datItems);
+            Assert.False(actual);
+        }
+
+        [Fact]
+        public void ContainsWritable_Writable_True()
+        {
+            List<DatItem> datItems = [new Rom()];
+            DatFile datFile = new Formats.Logiqx(null, deprecated: false);
+
+            bool actual = datFile.ContainsWritable(datItems);
+            Assert.True(actual);
+        }
 
         #endregion
 

SabreTools.DatFiles/DatFile.cs

@@ -431,15 +431,15 @@ namespace SabreTools.DatFiles
         protected internal virtual List<string>? GetMissingRequiredFields(DatItem datItem) => null;
 
         /// <summary>
-        /// Get if a machine contains any writable items
+        /// Get if a list contains any writable items
         /// </summary>
         /// <param name="datItems">DatItems to check</param>
-        /// <returns>True if the machine contains at least one writable item, false otherwise</returns>
+        /// <returns>True if the list contains at least one writable item, false otherwise</returns>
-        /// <remarks>Empty machines are kept with this</remarks>
+        /// <remarks>Empty list are kept with this</remarks>
         protected internal bool ContainsWritable(List<DatItem> datItems)
         {
-            // Empty machines are considered writable
+            // Empty list are considered writable
-            if (datItems == null || datItems.Count == 0)
+            if (datItems.Count == 0)
                 return true;
 
             foreach (DatItem datItem in datItems)