diff --git a/src/System.Memory/tests/ReadOnlySpan/IndexOfAny.byte.cs b/src/System.Memory/tests/ReadOnlySpan/IndexOfAny.byte.cs
index 1a62c4067749..b6384aacaff1 100644
--- a/src/System.Memory/tests/ReadOnlySpan/IndexOfAny.byte.cs
+++ b/src/System.Memory/tests/ReadOnlySpan/IndexOfAny.byte.cs
@@ -58,9 +58,10 @@ public static void IndexOfAnyStrings_Byte(string raw, string search, char expect
         [Fact]
         public static void ZeroLengthIndexOfTwo_Byte()
         {
-            ReadOnlySpan<byte> sp = new ReadOnlySpan<byte>(Array.Empty<byte>());
-            int idx = sp.IndexOfAny<byte>(0, 0);
-            Assert.Equal(-1, idx);
+            ReadOnlySpan<byte> span = new ReadOnlySpan<byte>(Array.Empty<byte>());
+
+            Assert.Equal(-1, span.IndexOfAny<byte>(0, 0));
+            Assert.Equal(-1, span.IndexOfAny(new byte[2]));
         }
 
         [Fact]
@@ -80,8 +81,9 @@ public static void DefaultFilledIndexOfTwo_Byte()
                     int index = rnd.Next(0, 2) == 0 ? 0 : 1;
                     byte target0 = targets[index];
                     byte target1 = targets[(index + 1) % 2];
-                    int idx = span.IndexOfAny(target0, target1);
-                    Assert.Equal(0, idx);
+
+                    Assert.Equal(0, span.IndexOfAny(target0, target1));
+                    Assert.Equal(0, span.IndexOfAny(new[] { target0, target1 }));
                 }
             }
         }
@@ -102,24 +104,27 @@ public static void TestMatchTwo_Byte()
                 {
                     byte target0 = a[targetIndex];
                     byte target1 = 0;
-                    int idx = span.IndexOfAny(target0, target1);
-                    Assert.Equal(targetIndex, idx);
+
+                    Assert.Equal(targetIndex, span.IndexOfAny(target0, target1));
+                    Assert.Equal(targetIndex, span.IndexOfAny(new[] { target0, target1 }));
                 }
 
                 for (int targetIndex = 0; targetIndex < length - 1; targetIndex++)
                 {
                     byte target0 = a[targetIndex];
                     byte target1 = a[targetIndex + 1];
-                    int idx = span.IndexOfAny(target0, target1);
-                    Assert.Equal(targetIndex, idx);
+
+                    Assert.Equal(targetIndex, span.IndexOfAny(target0, target1));
+                    Assert.Equal(targetIndex, span.IndexOfAny(new[] { target0, target1 }));
                 }
 
                 for (int targetIndex = 0; targetIndex < length - 1; targetIndex++)
                 {
                     byte target0 = 0;
                     byte target1 = a[targetIndex + 1];
-                    int idx = span.IndexOfAny(target0, target1);
-                    Assert.Equal(targetIndex + 1, idx);
+
+                    Assert.Equal(targetIndex + 1, span.IndexOfAny(target0, target1));
+                    Assert.Equal(targetIndex + 1, span.IndexOfAny(new[] { target0, target1 }));
                 }
             }
         }
@@ -135,8 +140,8 @@ public static void TestNoMatchTwo_Byte()
                 byte target1 = (byte)rnd.Next(1, 256);
                 ReadOnlySpan<byte> span = new ReadOnlySpan<byte>(a);
 
-                int idx = span.IndexOfAny(target0, target1);
-                Assert.Equal(-1, idx);
+                Assert.Equal(-1, span.IndexOfAny(target0, target1));
+                Assert.Equal(-1, span.IndexOfAny(new[] { target0, target1 }));
             }
         }
 
@@ -157,8 +162,9 @@ public static void TestMultipleMatchTwo_Byte()
                 a[length - 3] = 200;
 
                 ReadOnlySpan<byte> span = new ReadOnlySpan<byte>(a);
-                int idx = span.IndexOfAny<byte>(200, 200);
-                Assert.Equal(length - 3, idx);
+
+                Assert.Equal(length - 3, span.IndexOfAny<byte>(200, 200));
+                Assert.Equal(length - 3, span.IndexOfAny<byte>(new byte[] { 200, 200 }));
             }
         }
 
@@ -171,8 +177,9 @@ public static void MakeSureNoChecksGoOutOfRangeTwo_Byte()
                 a[0] = 99;
                 a[length + 1] = 98;
                 ReadOnlySpan<byte> span = new ReadOnlySpan<byte>(a, 1, length - 1);
-                int index = span.IndexOfAny<byte>(99, 98);
-                Assert.Equal(-1, index);
+
+                Assert.Equal(-1, span.IndexOfAny<byte>(99, 98));
+                Assert.Equal(-1, span.IndexOfAny<byte>(new byte[] { 99, 98 }));
             }
 
             for (int length = 1; length < byte.MaxValue; length++)
@@ -181,17 +188,19 @@ public static void MakeSureNoChecksGoOutOfRangeTwo_Byte()
                 a[0] = 99;
                 a[length + 1] = 99;
                 ReadOnlySpan<byte> span = new ReadOnlySpan<byte>(a, 1, length - 1);
-                int index = span.IndexOfAny<byte>(99, 99);
-                Assert.Equal(-1, index);
+
+                Assert.Equal(-1, span.IndexOfAny<byte>(99, 99));
+                Assert.Equal(-1, span.IndexOfAny<byte>(new byte[] { 99, 99 }));
             }
         }
 
         [Fact]
         public static void ZeroLengthIndexOfThree_Byte()
         {
-            ReadOnlySpan<byte> sp = new ReadOnlySpan<byte>(Array.Empty<byte>());
-            int idx = sp.IndexOfAny<byte>(0, 0, 0);
-            Assert.Equal(-1, idx);
+            ReadOnlySpan<byte> span = new ReadOnlySpan<byte>(Array.Empty<byte>());
+
+            Assert.Equal(-1, span.IndexOfAny<byte>(0, 0, 0));
+            Assert.Equal(-1, span.IndexOfAny(new byte[3]));
         }
 
         [Fact]
@@ -212,8 +221,9 @@ public static void DefaultFilledIndexOfThree_Byte()
                     byte target0 = targets[index];
                     byte target1 = targets[(index + 1) % 2];
                     byte target2 = targets[(index + 1) % 3];
-                    int idx = span.IndexOfAny(target0, target1, target2);
-                    Assert.Equal(0, idx);
+
+                    Assert.Equal(0, span.IndexOfAny(target0, target1, target2));
+                    Assert.Equal(0, span.IndexOfAny(new[] { target0, target1, target2 }));
                 }
             }
         }
@@ -235,8 +245,9 @@ public static void TestMatchThree_Byte()
                     byte target0 = a[targetIndex];
                     byte target1 = 0;
                     byte target2 = 0;
-                    int idx = span.IndexOfAny(target0, target1, target2);
-                    Assert.Equal(targetIndex, idx);
+
+                    Assert.Equal(targetIndex, span.IndexOfAny(target0, target1, target2));
+                    Assert.Equal(targetIndex, span.IndexOfAny(new[] { target0, target1, target2 }));
                 }
 
                 for (int targetIndex = 0; targetIndex < length - 2; targetIndex++)
@@ -244,8 +255,9 @@ public static void TestMatchThree_Byte()
                     byte target0 = a[targetIndex];
                     byte target1 = a[targetIndex + 1];
                     byte target2 = a[targetIndex + 2];
-                    int idx = span.IndexOfAny(target0, target1, target2);
-                    Assert.Equal(targetIndex, idx);
+
+                    Assert.Equal(targetIndex, span.IndexOfAny(target0, target1, target2));
+                    Assert.Equal(targetIndex, span.IndexOfAny(new[] { target0, target1, target2 }));
                 }
 
                 for (int targetIndex = 0; targetIndex < length - 2; targetIndex++)
@@ -253,8 +265,9 @@ public static void TestMatchThree_Byte()
                     byte target0 = 0;
                     byte target1 = 0;
                     byte target2 = a[targetIndex + 2];
-                    int idx = span.IndexOfAny(target0, target1, target2);
-                    Assert.Equal(targetIndex + 2, idx);
+
+                    Assert.Equal(targetIndex + 2, span.IndexOfAny(target0, target1, target2));
+                    Assert.Equal(targetIndex + 2, span.IndexOfAny(new[] { target0, target1, target2 }));
                 }
             }
         }
@@ -271,8 +284,8 @@ public static void TestNoMatchThree_Byte()
                 byte target2 = (byte)rnd.Next(1, 256);
                 ReadOnlySpan<byte> span = new ReadOnlySpan<byte>(a);
 
-                int idx = span.IndexOfAny(target0, target1, target2);
-                Assert.Equal(-1, idx);
+                Assert.Equal(-1, span.IndexOfAny(target0, target1, target2));
+                Assert.Equal(-1, span.IndexOfAny(new[] { target0, target1, target2 }));
             }
         }
 
@@ -294,8 +307,9 @@ public static void TestMultipleMatchThree_Byte()
                 a[length - 4] = 200;
 
                 ReadOnlySpan<byte> span = new ReadOnlySpan<byte>(a);
-                int idx = span.IndexOfAny<byte>(200, 200, 200);
-                Assert.Equal(length - 4, idx);
+
+                Assert.Equal(length - 4, span.IndexOfAny<byte>(200, 200, 200));
+                Assert.Equal(length - 4, span.IndexOfAny<byte>(new byte[] { 200, 200, 200 }));
             }
         }
 
@@ -308,8 +322,9 @@ public static void MakeSureNoChecksGoOutOfRangeThree_Byte()
                 a[0] = 99;
                 a[length + 1] = 98;
                 ReadOnlySpan<byte> span = new ReadOnlySpan<byte>(a, 1, length - 1);
-                int index = span.IndexOfAny<byte>(99, 98, 99);
-                Assert.Equal(-1, index);
+
+                Assert.Equal(-1, span.IndexOfAny<byte>(99, 98, 99));
+                Assert.Equal(-1, span.IndexOfAny<byte>(new byte[] { 99, 98, 99 }));
             }
 
             for (int length = 1; length < byte.MaxValue; length++)
@@ -318,8 +333,9 @@ public static void MakeSureNoChecksGoOutOfRangeThree_Byte()
                 a[0] = 99;
                 a[length + 1] = 99;
                 ReadOnlySpan<byte> span = new ReadOnlySpan<byte>(a, 1, length - 1);
-                int index = span.IndexOfAny<byte>(99, 99, 99);
-                Assert.Equal(-1, index);
+
+                Assert.Equal(-1, span.IndexOfAny<byte>(99, 99, 99));
+                Assert.Equal(-1, span.IndexOfAny<byte>(new byte[] { 99, 99, 99 }));
             }
         }
 
diff --git a/src/System.Memory/tests/Span/IndexOfAny.byte.cs b/src/System.Memory/tests/Span/IndexOfAny.byte.cs
index 699477dd80eb..a5250a03e582 100644
--- a/src/System.Memory/tests/Span/IndexOfAny.byte.cs
+++ b/src/System.Memory/tests/Span/IndexOfAny.byte.cs
@@ -58,9 +58,10 @@ public static void IndexOfAnyStrings_Byte(string raw, string search, char expect
         [Fact]
         public static void ZeroLengthIndexOfTwo_Byte()
         {
-            Span<byte> sp = new Span<byte>(Array.Empty<byte>());
-            int idx = sp.IndexOfAny<byte>(0, 0);
-            Assert.Equal(-1, idx);
+            Span<byte> span = new Span<byte>(Array.Empty<byte>());
+
+            Assert.Equal(-1, span.IndexOfAny<byte>(0, 0));
+            Assert.Equal(-1, span.IndexOfAny(new byte[2]));
         }
 
         [Fact]
@@ -80,8 +81,9 @@ public static void DefaultFilledIndexOfTwo_Byte()
                     int index = rnd.Next(0, 2) == 0 ? 0 : 1;
                     byte target0 = targets[index];
                     byte target1 = targets[(index + 1) % 2];
-                    int idx = span.IndexOfAny(target0, target1);
-                    Assert.Equal(0, idx);
+
+                    Assert.Equal(0, span.IndexOfAny(target0, target1));
+                    Assert.Equal(0, span.IndexOfAny(new[] { target0, target1 }));
                 }
             }
         }
@@ -102,24 +104,27 @@ public static void TestMatchTwo_Byte()
                 {
                     byte target0 = a[targetIndex];
                     byte target1 = 0;
-                    int idx = span.IndexOfAny(target0, target1);
-                    Assert.Equal(targetIndex, idx);
+
+                    Assert.Equal(targetIndex, span.IndexOfAny(target0, target1));
+                    Assert.Equal(targetIndex, span.IndexOfAny(new[] { target0, target1 }));
                 }
 
                 for (int targetIndex = 0; targetIndex < length - 1; targetIndex++)
                 {
                     byte target0 = a[targetIndex];
                     byte target1 = a[targetIndex + 1];
-                    int idx = span.IndexOfAny(target0, target1);
-                    Assert.Equal(targetIndex, idx);
+
+                    Assert.Equal(targetIndex, span.IndexOfAny(target0, target1));
+                    Assert.Equal(targetIndex, span.IndexOfAny(new[] { target0, target1 }));
                 }
 
                 for (int targetIndex = 0; targetIndex < length - 1; targetIndex++)
                 {
                     byte target0 = 0;
                     byte target1 = a[targetIndex + 1];
-                    int idx = span.IndexOfAny(target0, target1);
-                    Assert.Equal(targetIndex + 1, idx);
+
+                    Assert.Equal(targetIndex + 1, span.IndexOfAny(target0, target1));
+                    Assert.Equal(targetIndex + 1, span.IndexOfAny(new[] { target0, target1 }));
                 }
             }
         }
@@ -135,8 +140,8 @@ public static void TestNoMatchTwo_Byte()
                 byte target1 = (byte)rnd.Next(1, 256);
                 Span<byte> span = new Span<byte>(a);
 
-                int idx = span.IndexOfAny(target0, target1);
-                Assert.Equal(-1, idx);
+                Assert.Equal(-1, span.IndexOfAny(target0, target1));
+                Assert.Equal(-1, span.IndexOfAny(new[] { target0, target1 }));
             }
         }
 
@@ -157,8 +162,9 @@ public static void TestMultipleMatchTwo_Byte()
                 a[length - 3] = 200;
 
                 Span<byte> span = new Span<byte>(a);
-                int idx = span.IndexOfAny<byte>(200, 200);
-                Assert.Equal(length - 3, idx);
+
+                Assert.Equal(length - 3, span.IndexOfAny<byte>(200, 200));
+                Assert.Equal(length - 3, span.IndexOfAny<byte>(new byte[] { 200, 200 }));
             }
         }
 
@@ -171,8 +177,9 @@ public static void MakeSureNoChecksGoOutOfRangeTwo_Byte()
                 a[0] = 99;
                 a[length + 1] = 98;
                 Span<byte> span = new Span<byte>(a, 1, length - 1);
-                int index = span.IndexOfAny<byte>(99, 98);
-                Assert.Equal(-1, index);
+
+                Assert.Equal(-1, span.IndexOfAny<byte>(99, 98));
+                Assert.Equal(-1, span.IndexOfAny<byte>(new byte[] { 99, 98 }));
             }
 
             for (int length = 1; length < byte.MaxValue; length++)
@@ -181,17 +188,19 @@ public static void MakeSureNoChecksGoOutOfRangeTwo_Byte()
                 a[0] = 99;
                 a[length + 1] = 99;
                 Span<byte> span = new Span<byte>(a, 1, length - 1);
-                int index = span.IndexOfAny<byte>(99, 99);
-                Assert.Equal(-1, index);
+
+                Assert.Equal(-1, span.IndexOfAny<byte>(99, 99));
+                Assert.Equal(-1, span.IndexOfAny<byte>(new byte[] { 99, 99 }));
             }
         }
 
         [Fact]
         public static void ZeroLengthIndexOfThree_Byte()
         {
-            Span<byte> sp = new Span<byte>(Array.Empty<byte>());
-            int idx = sp.IndexOfAny<byte>(0, 0, 0);
-            Assert.Equal(-1, idx);
+            Span<byte> span = new Span<byte>(Array.Empty<byte>());
+
+            Assert.Equal(-1, span.IndexOfAny<byte>(0, 0, 0));
+            Assert.Equal(-1, span.IndexOfAny(new byte[3]));
         }
 
         [Fact]
@@ -212,8 +221,9 @@ public static void DefaultFilledIndexOfThree_Byte()
                     byte target0 = targets[index];
                     byte target1 = targets[(index + 1) % 2];
                     byte target2 = targets[(index + 1) % 3];
-                    int idx = span.IndexOfAny(target0, target1, target2);
-                    Assert.Equal(0, idx);
+
+                    Assert.Equal(0, span.IndexOfAny(target0, target1, target2));
+                    Assert.Equal(0, span.IndexOfAny(new[] { target0, target1, target2 }));
                 }
             }
         }
@@ -235,8 +245,9 @@ public static void TestMatchThree_Byte()
                     byte target0 = a[targetIndex];
                     byte target1 = 0;
                     byte target2 = 0;
-                    int idx = span.IndexOfAny(target0, target1, target2);
-                    Assert.Equal(targetIndex, idx);
+
+                    Assert.Equal(targetIndex, span.IndexOfAny(target0, target1, target2));
+                    Assert.Equal(targetIndex, span.IndexOfAny(new[] { target0, target1, target2 }));
                 }
 
                 for (int targetIndex = 0; targetIndex < length - 2; targetIndex++)
@@ -244,8 +255,9 @@ public static void TestMatchThree_Byte()
                     byte target0 = a[targetIndex];
                     byte target1 = a[targetIndex + 1];
                     byte target2 = a[targetIndex + 2];
-                    int idx = span.IndexOfAny(target0, target1, target2);
-                    Assert.Equal(targetIndex, idx);
+
+                    Assert.Equal(targetIndex, span.IndexOfAny(target0, target1, target2));
+                    Assert.Equal(targetIndex, span.IndexOfAny(new[] { target0, target1, target2 }));
                 }
 
                 for (int targetIndex = 0; targetIndex < length - 2; targetIndex++)
@@ -253,8 +265,9 @@ public static void TestMatchThree_Byte()
                     byte target0 = 0;
                     byte target1 = 0;
                     byte target2 = a[targetIndex + 2];
-                    int idx = span.IndexOfAny(target0, target1, target2);
-                    Assert.Equal(targetIndex + 2, idx);
+
+                    Assert.Equal(targetIndex + 2, span.IndexOfAny(target0, target1, target2));
+                    Assert.Equal(targetIndex + 2, span.IndexOfAny(new[] { target0, target1, target2 }));
                 }
             }
         }
@@ -271,8 +284,8 @@ public static void TestNoMatchThree_Byte()
                 byte target2 = (byte)rnd.Next(1, 256);
                 Span<byte> span = new Span<byte>(a);
 
-                int idx = span.IndexOfAny(target0, target1, target2);
-                Assert.Equal(-1, idx);
+                Assert.Equal(-1, span.IndexOfAny(target0, target1, target2));
+                Assert.Equal(-1, span.IndexOfAny(new[] { target0, target1, target2 }));
             }
         }
 
@@ -294,8 +307,9 @@ public static void TestMultipleMatchThree_Byte()
                 a[length - 4] = 200;
 
                 Span<byte> span = new Span<byte>(a);
-                int idx = span.IndexOfAny<byte>(200, 200, 200);
-                Assert.Equal(length - 4, idx);
+
+                Assert.Equal(length - 4, span.IndexOfAny<byte>(200, 200, 200));
+                Assert.Equal(length - 4, span.IndexOfAny<byte>(new byte[] { 200, 200, 200 }));
             }
         }
 
@@ -308,8 +322,9 @@ public static void MakeSureNoChecksGoOutOfRangeThree_Byte()
                 a[0] = 99;
                 a[length + 1] = 98;
                 Span<byte> span = new Span<byte>(a, 1, length - 1);
-                int index = span.IndexOfAny<byte>(99, 98, 99);
-                Assert.Equal(-1, index);
+
+                Assert.Equal(-1, span.IndexOfAny<byte>(99, 98, 99));
+                Assert.Equal(-1, span.IndexOfAny<byte>(new byte[] { 99, 98, 99 }));
             }
 
             for (int length = 1; length < byte.MaxValue; length++)
@@ -318,8 +333,9 @@ public static void MakeSureNoChecksGoOutOfRangeThree_Byte()
                 a[0] = 99;
                 a[length + 1] = 99;
                 Span<byte> span = new Span<byte>(a, 1, length - 1);
-                int index = span.IndexOfAny<byte>(99, 99, 99);
-                Assert.Equal(-1, index);
+
+                Assert.Equal(-1, span.IndexOfAny<byte>(99, 99, 99));
+                Assert.Equal(-1, span.IndexOfAny<byte>(new byte[] { 99, 99, 99 }));
             }
         }