Refactor exceptions to use InvalidCharacterException.

Replaced `ArgumentException` with the new `InvalidCharacterException` for better semantic clarity when handling invalid input.
Added `InvalidCharacterException` class and updated related tests accordingly to align with these changes.
Updated the changelog to document the addition.

Resolves: No entry

Author: shinji-san

CHANGELOG.md

@@ -5,6 +5,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+### Added
+- Add `InvalidCharacterException` to throw an exception if the input string contains invalid characters.
+
 ### Changed
 - Renamed `Luhn.ConvertAlphaNumericToNumeric` to `Luhn.AlphaNumericToNumeric`
 

src/InvalidCharacterException.cs

@@ -0,0 +1,94 @@
+// ----------------------------------------------------------------------------
+// <copyright file="InvalidCharacterException.cs" company="Private">
+// Copyright (c) 2025 All Rights Reserved
+// </copyright>
+// <author>Sebastian Walther</author>
+// <date>01/01/2025 09:00:26 PM</date>
+// ----------------------------------------------------------------------------
+
+#region License
+
+// ----------------------------------------------------------------------------
+// Copyright 2025 Sebastian Walther
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+#endregion
+
+using System;
+using System.Runtime.Serialization;
+
+namespace LuhnDotNet
+{
+    /// <summary>
+    /// The exception that is thrown when an invalid character is encountered within an argument.
+    /// </summary>
+    [Serializable]
+    public class InvalidCharacterException : ArgumentException
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="InvalidCharacterException"/> class.
+        /// </summary>
+        public InvalidCharacterException() : base("Invalid character encountered in argument.")
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="InvalidCharacterException"/> class with a specified error message.
+        /// </summary>
+        /// <param name="message">The message that describes the error.</param>
+        public InvalidCharacterException(string message) : base(message)
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="InvalidCharacterException"/> class with a specified error message
+        /// and the name of the parameter that caused this exception.
+        /// </summary>
+        /// <param name="message">The error message that explains the reason for the exception.</param>
+        /// <param name="paramName">The name of the parameter that caused the current exception.</param>
+        public InvalidCharacterException(string message, string paramName) : base(message, paramName)
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="InvalidCharacterException"/> class with a specified error message,
+        /// the parameter name, and a reference to the inner exception that is the cause of this exception.
+        /// </summary>
+        /// <param name="message">The error message that explains the reason for the exception.</param>
+        /// <param name="paramName">The name of the parameter that caused the current exception.</param>
+        /// <param name="innerException">The exception that is the cause of the current exception
+        /// or a null reference if no inner exception is specified.</param>
+        public InvalidCharacterException(string message, string paramName, Exception innerException) : base(message, paramName, innerException)
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="InvalidCharacterException"/> class with serialized data.
+        /// </summary>
+        /// <param name="info">The <see cref="SerializationInfo"/> that holds the serialized object data about the exception being thrown.</param>
+        /// <param name="context">The <see cref="StreamingContext"/> that contains contextual information about the source or destination.</param>
+        [Obsolete(
+            "This constructor is obsolete and will be removed in a future version. Use InvalidCharacterException(string message, string paramName, Exception innerException) instead.",
+            false)]
+        protected InvalidCharacterException(SerializationInfo info, StreamingContext context) : base(info, context)
+        {
+        }
+    }
+}

src/Luhn.cs

@@ -63,7 +63,7 @@ public static class Luhn
         /// </summary>
         /// <param name="number">An identification number w/o check digit.</param>
         /// <returns>The calculated Luhn check digit.</returns>
-        /// <exception cref="ArgumentException"><paramref name="number"/> is not valid.
+        /// <exception cref="InvalidCharacterException"><paramref name="number"/> is not valid.
         /// It contains none-numeric characters.</exception>
         [SuppressMessage("ReSharper", "UnusedMember.Global")]
         [SuppressMessage("ReSharper", "HeapView.ObjectAllocation")]
@@ -76,7 +76,7 @@ public static byte ComputeLuhnCheckDigit(this ReadOnlySpan<char> number) =>
         /// </summary>
         /// <param name="number">An identification number w/o check digit.</param>
         /// <returns>The calculated Luhn check digit as a byte.</returns>
-        /// <exception cref="ArgumentException"><paramref name="number"/> is not valid.
+        /// <exception cref="InvalidCharacterException"><paramref name="number"/> is not valid.
         /// It contains none-numeric characters.</exception>
         [SuppressMessage("ReSharper", "UnusedMember.Global")]
         [SuppressMessage("ReSharper", "HeapView.ObjectAllocation")]
@@ -93,7 +93,7 @@ public static byte ComputeLuhnCheckDigit(this string number) =>
         /// </summary>
         /// <param name="number">An identification number w/o check digit.</param>
         /// <returns>The calculated Luhn number.</returns>
-        /// <exception cref="ArgumentException"><paramref name="number"/> is not valid.
+        /// <exception cref="InvalidCharacterException"><paramref name="number"/> is not valid.
         /// It contains none-numeric characters.</exception>
         [SuppressMessage("ReSharper", "UnusedMember.Global")]
         [SuppressMessage("ReSharper", "HeapView.ObjectAllocation")]
@@ -109,7 +109,7 @@ public static string ComputeLuhnNumber(this ReadOnlySpan<char> number)
         /// </summary>
         /// <param name="number">An identification number w/o check digit.</param>
         /// <returns>The calculated Luhn number.</returns>
-        /// <exception cref="ArgumentException"><paramref name="number"/> is not valid.
+        /// <exception cref="InvalidCharacterException"><paramref name="number"/> is not valid.
         /// It contains none-numeric characters.</exception>
         [SuppressMessage("ReSharper", "UnusedMember.Global")]
         [SuppressMessage("ReSharper", "HeapView.ObjectAllocation")]
@@ -134,7 +134,7 @@ public static string ComputeLuhnNumber(this string number)
         /// <param name="luhnNumber">An identification number w/ check digit (Luhn Number).</param>
         /// <returns><see langword="true" /> if the <paramref name="luhnNumber"/> is valid;
         /// otherwise <see langword="false" /></returns>
-        /// <exception cref="ArgumentException"><paramref name="luhnNumber"/> is not valid.
+        /// <exception cref="InvalidCharacterException"><paramref name="luhnNumber"/> is not valid.
         /// It contains none-numeric characters.</exception>
         /// <remarks>The check digit must be at the end of the <paramref name="luhnNumber"/>
         /// (on the right side).</remarks>
@@ -150,7 +150,7 @@ public static bool IsValidLuhnNumber(this ReadOnlySpan<char> luhnNumber) =>
         /// <param name="luhnNumber">An identification number w/ check digit (Luhn Number).</param>
         /// <returns><see langword="true" /> if the <paramref name="luhnNumber"/> is valid;
         /// otherwise <see langword="false" /></returns>
-        /// <exception cref="ArgumentException"><paramref name="luhnNumber"/> is not valid.
+        /// <exception cref="InvalidCharacterException"><paramref name="luhnNumber"/> is not valid.
         /// It contains none-numeric characters.</exception>
         /// <remarks>The check digit must be at the end of the <paramref name="luhnNumber"/>
         /// (on the right side).</remarks>
@@ -171,7 +171,7 @@ public static bool IsValidLuhnNumber(this string luhnNumber) =>
         /// <param name="number">Identification number w/o Luhn check digit</param>
         /// <returns><see langword="true" /> if the <paramref name="number"/> is valid;
         /// otherwise <see langword="false" /></returns>
-        /// <exception cref="ArgumentException"><paramref name="number"/> is not valid.
+        /// <exception cref="InvalidCharacterException"><paramref name="number"/> is not valid.
         /// It contains none-numeric characters.</exception>
         /// <exception cref="ArgumentOutOfRangeException">The <paramref name="checkDigit"/> value is greater than 9.
         /// The <paramref name="checkDigit"/> value must be between 0 and 9.</exception>
@@ -203,7 +203,7 @@ public static bool IsValidLuhnCheckDigit(this byte checkDigit, ReadOnlySpan<char
         /// <param name="number">Identification number w/o Luhn check digit</param>
         /// <returns><see langword="true" /> if the <paramref name="number"/> is valid;
         /// otherwise <see langword="false" /></returns>
-        /// <exception cref="ArgumentException"><paramref name="number"/> is not valid.
+        /// <exception cref="InvalidCharacterException"><paramref name="number"/> is not valid.
         /// It contains none-numeric characters.</exception>
         /// <exception cref="ArgumentOutOfRangeException">The <paramref name="checkDigit"/> value is greater than 9.
         /// The <paramref name="checkDigit"/> value must be between 0 and 9.</exception>
@@ -240,7 +240,7 @@ public static bool IsValidLuhnCheckDigit(this byte checkDigit, string number)
         /// <param name="alphaNumeric">The alphanumeric string to convert.</param>
         /// <returns>A numeric string where each letter in the input string is replaced by its decimal ASCII value
         /// minus 55.</returns>
-        /// <exception cref="ArgumentException">The <paramref name="alphaNumeric"/> contains a character
+        /// <exception cref="InvalidCharacterException">The <paramref name="alphaNumeric"/> contains a character
         /// that is neither a letter nor a digit.</exception>
         /// <remarks>
         /// This method iterates over each character in the input string. If the character is a letter, it is replaced
@@ -268,7 +268,7 @@ public static string AlphaNumericToNumeric(this string alphaNumeric)
                 }
                 else
                 {
-                    throw new ArgumentException($"The character '{c}' is not a letter or a digit!", nameof(alphaNumeric));
+                    throw new InvalidCharacterException($"The character '{c}' is not a letter or a digit!", nameof(alphaNumeric));
                 }
             }
 
@@ -290,7 +290,7 @@ public static string AlphaNumericToNumeric(this string alphaNumeric)
                 }
                 else
                 {
-                    throw new ArgumentException($"The character '{c}' is not a letter or a digit!", nameof(alphaNumeric));
+                    throw new InvalidCharacterException($"The character '{c}' is not a letter or a digit!", nameof(alphaNumeric));
                 }
             }
 
@@ -340,13 +340,13 @@ private static IEnumerable<uint> DoubleEverySecondDigit(this IEnumerable<uint> d
         /// </summary>
         /// <param name="number">An identification number</param>
         /// <returns>The trimmed identification number if valid</returns>
-        /// <exception cref="ArgumentException"><paramref name="number"/> is not a valid number</exception>
+        /// <exception cref="InvalidCharacterException"><paramref name="number"/> is not a valid number</exception>
         private static string ValidateAndTrimNumber(this string number)
         {
             string trimmedNumber = number?.Trim();
             if (string.IsNullOrWhiteSpace(trimmedNumber) || !Regex.IsMatch(trimmedNumber, @"^\d+$"))
             {
-                throw new ArgumentException($"The string '{number}' is not a number!", nameof(number));
+                throw new InvalidCharacterException($"The string '{number}' is not a number!", nameof(number));
             }
 
             return trimmedNumber;
@@ -359,13 +359,13 @@ private static string ValidateAndTrimNumber(this string number)
         /// </summary>
         /// <param name="number">An identification number</param>
         /// <returns>The trimmed identification number if valid</returns>
-        /// <exception cref="ArgumentException"><paramref name="number"/> is not a valid number</exception>
+        /// <exception cref="InvalidCharacterException"><paramref name="number"/> is not a valid number</exception>
         private static ReadOnlySpan<char> ValidateAndTrimNumber(this ReadOnlySpan<char> number)
         {
             var trimmedNumber = number.Trim();
             if (trimmedNumber.Length == 0 || !trimmedNumber.IsDigits())
             {
-                throw new ArgumentException($"The string '{number}' is not a number!", nameof(number));
+                throw new InvalidCharacterException($"The string '{number}' is not a number!", nameof(number));
             }
 
             return trimmedNumber;