Implement EqualsExactly extension

SabreTools.Matching.Test/ExtensionsTests.cs

@@ -237,6 +237,58 @@ namespace SabreTools.Matching.Test
 
         #endregion
 
+        #region Equals Exactly
+
+        [Fact]
+        public void EqualsExactly_EmptyStack_NoMatches()
+        {
+            byte[] stack = [];
+            bool found = stack.EqualsExactly([0x01]);
+            Assert.False(found);
+        }
+
+        [Fact]
+        public void EqualsExactly_EmptyNeedle_NoMatches()
+        {
+            byte[] stack = [0x01];
+            bool found = stack.EqualsExactly(Array.Empty<byte>());
+            Assert.False(found);
+        }
+
+        [Fact]
+        public void EqualsExactly_ShorterNeedle_NoMatches()
+        {
+            byte[] stack = [0x01, 0x02];
+            bool found = stack.EqualsExactly([0x01]);
+            Assert.False(found);
+        }
+
+        [Fact]
+        public void EqualsExactly_LongerNeedle_NoMatches()
+        {
+            byte[] stack = [0x01];
+            bool found = stack.EqualsExactly([0x01, 0x02]);
+            Assert.False(found);
+        }
+
+        [Fact]
+        public void EqualsExactly_Matching_Matches()
+        {
+            byte[] stack = [0x01, 0x02];
+            bool found = stack.EqualsExactly([0x01, 0x02]);
+            Assert.True(found);
+        }
+
+        [Fact]
+        public void EqualsExactly_Mismatch_NoMatches()
+        {
+            byte[] stack = [0x01, 0x03];
+            bool found = stack.EqualsExactly([0x01, 0x02]);
+            Assert.False(found);
+        }
+
+        #endregion
+
         #region Starts With
 
         [Fact]

SabreTools.Matching/Extensions.cs

@@ -4,7 +4,6 @@ using SabreTools.Matching.Content;
 
 namespace SabreTools.Matching
 {
-    // TODO: Write SequenceEqual equivilent: EqualsExactly
     public static class Extensions
     {
         /// <summary>
@@ -137,6 +136,35 @@ namespace SabreTools.Matching
             return matcher.Match(stack, reverse: true);
         }
 
+        /// <summary>
+        /// Check if a byte array exactly matches another
+        /// </summary>
+        /// <param name="stack">Byte array to search within</param>
+        /// <param name="needle">Byte array representing the search value</param>
+        public static bool EqualsExactly(this byte[] stack, byte[] needle)
+        {
+            byte?[] nullableNeedle = Array.ConvertAll(needle, b => (byte?)b);
+            return EqualsExactly(stack, nullableNeedle);
+        }
+
+        /// <summary>
+        /// Check if a byte array exactly matches another
+        /// </summary>
+        /// <param name="stack">Byte array to search within</param>
+        /// <param name="needle">Byte array representing the search value</param>
+        public static bool EqualsExactly(this byte[] stack, byte?[] needle)
+        {
+            // If either set is null or empty
+            if (stack.Length == 0 || needle.Length == 0)
+                return false;
+
+            // If the needle is not the exact length of the stack
+            if (needle.Length != stack.Length)
+                return false;
+
+            return FirstPosition(stack, needle, start: 0, end: 1) == 0;
+        }
+
         /// <summary>
         /// Check if a byte array starts with another
         /// </summary>