Fix: unicode escape for cli input

src/Neo.ConsoleService/CommandTokenizer.cs

@@ -11,6 +11,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Globalization;
 using System.Linq;
 using System.Text;
 
@@ -35,10 +36,51 @@ private static char EscapedChar(char ch)
                 'e' => '\e',
                 '0' => '\0',
                 ' ' => ' ',
-                _ => throw new ArgumentException($"Invalid escaped character: {ch}")
+                _ => throw new ArgumentException($"Invalid escaped character: \\{ch}. " +
+                    "If you don't want to use escape character, please use backtick(`) to wrap the string.")
             };
         }
 
+        private static (char, int) EscapedChar(string commandLine, int index)
+        {
+            index++; // next char after \
+            if (index >= commandLine.Length)
+            {
+                throw new ArgumentException("Invalid escape sequence. The command line ends with a backslash character.");
+            }
+
+            if (commandLine[index] == 'x')
+            {
+                if (index + 2 >= commandLine.Length)
+                    throw new ArgumentException("Invalid escape sequence. Too few hex digits after \\x");
+
+                if (!byte.TryParse(commandLine.AsSpan(index + 1, 2), NumberStyles.AllowHexSpecifier, null, out var ch))
+                {
+                    throw new ArgumentException($"Invalid hex digits after \\x. " +
+                        "If you don't want to use escape character, please use backtick(`) to wrap the string.");
+                }
+
+                return new((char)ch, 1 + 2);
+            }
+
+            if (commandLine[index] == 'u')
+            {
+                if (index + 4 >= commandLine.Length)
+                    throw new ArgumentException("Invalid escape sequence. Too few hex digits after \\u");
+
+                if (!ushort.TryParse(commandLine.AsSpan(index + 1, 4), NumberStyles.AllowHexSpecifier, null, out var ch))
+                {
+                    throw new ArgumentException($"Invalid hex digits after \\u. " +
+                        "If you don't want to use escape character, please use backtick(`) to wrap the string.");
+                }
+
+                // handle invalid surrogate pairs if needed, but good enough for a cli tool
+                return new((char)ch, 1 + 4);
+            }
+
+            return new(EscapedChar(commandLine[index]), 1);
+        }
+
         /// <summary>
         /// Tokenize a command line
         /// </summary>
@@ -61,13 +103,9 @@ public static List<CommandToken> Tokenize(this string commandLine)
                 var ch = commandLine[index];
                 if (ch == '\\' && quoteChar != CommandToken.NoEscapedChar)
                 {
-                    index++;
-                    if (index >= commandLine.Length)
-                    {
-                        throw new ArgumentException("Unexpected end of command line while processing escape sequence." +
-                            " The command line ends with a backslash character.");
-                    }
-                    token.Append(EscapedChar(commandLine[index]));
+                    (var escapedChar, var length) = EscapedChar(commandLine, index);
+                    token.Append(escapedChar);
+                    index += length;
                 }
                 else if (quoteChar != CommandToken.NoQuoteChar)
                 {

src/Neo.ConsoleService/ConsoleServiceBase.cs

@@ -343,7 +343,7 @@ 2. Indicator Arguments (Named Parameters)
              - Boolean: Can be specified without a value (defaults to true), true/false, 1/0, yes/no, y/n
              - Enum: Case-insensitive enum value names
              - JSON: Input as JSON string
-             - Escape characters: \\, \", \', \n, \r, \t, \v, \b, \f, \a, \e, \0, \ (whitespace).
+             - Escape characters: \\, \", \', \n, \r, \t, \v, \b, \f, \a, \e, \0, \ (whitespace), \xHH, \uHHHH.
                 If want to input without escape, quote the value with backtick(`).
             """);
         }

tests/Neo.ConsoleService.Tests/UT_CommandTokenizer.cs

@@ -10,6 +10,7 @@
 // modifications are permitted.
 
 using Microsoft.VisualStudio.TestTools.UnitTesting;
+using System;
 
 namespace Neo.ConsoleService.Tests
 {
@@ -141,5 +142,105 @@ public void TestBackQuote()
             Assert.AreEqual("123\"456", args[2].Value);
             Assert.AreEqual("`123\"456`", args[2].RawValue);
         }
+
+        [TestMethod]
+        public void TestUnicodeEscape()
+        {
+            // Test basic Unicode escape sequence
+            var cmd = "show \"\\u0041\""; // Should decode to 'A'
+            var args = CommandTokenizer.Tokenize(cmd);
+            Assert.AreEqual(3, args.Count);
+            Assert.AreEqual("show", args[0].Value);
+            Assert.AreEqual(" ", args[1].Value);
+            Assert.AreEqual("A", args[2].Value);
+
+            // Test Unicode escape sequence for emoji
+            cmd = "show \"\\uD83D\\uDE00\""; // Should decode to 😀
+            args = CommandTokenizer.Tokenize(cmd); // surrogate pairs
+            Assert.AreEqual(3, args.Count);
+            Assert.AreEqual("show", args[0].Value);
+            Assert.AreEqual(" ", args[1].Value);
+            Assert.AreEqual("😀", args[2].Value);
+
+            // Test Unicode escape sequence in single quotes
+            cmd = "show '\\u0048\\u0065\\u006C\\u006C\\u006F'"; // Should decode to "Hello"
+            args = CommandTokenizer.Tokenize(cmd);
+            Assert.AreEqual(3, args.Count);
+            Assert.AreEqual("show", args[0].Value);
+            Assert.AreEqual(" ", args[1].Value);
+            Assert.AreEqual("Hello", args[2].Value);
+
+            cmd = "show '\\x48\\x65\\x6C\\x6C\\x6F'"; // Should decode to "Hello"
+            args = CommandTokenizer.Tokenize(cmd);
+            Assert.AreEqual(3, args.Count);
+            Assert.AreEqual("show", args[0].Value);
+            Assert.AreEqual(" ", args[1].Value);
+            Assert.AreEqual("Hello", args[2].Value);
+        }
+
+        [TestMethod]
+        public void TestUnicodeEscapeErrors()
+        {
+            // Test incomplete Unicode escape sequence
+            Assert.ThrowsExactly<ArgumentException>(() => CommandTokenizer.Tokenize("show \"\\u123\""));
+
+            // Test invalid hex digits
+            Assert.ThrowsExactly<ArgumentException>(() => CommandTokenizer.Tokenize("show \"\\u12XY\""));
+
+            // Test Unicode escape at end of string
+            Assert.ThrowsExactly<ArgumentException>(() => CommandTokenizer.Tokenize("show \"\\u"));
+        }
+
+        [TestMethod]
+        public void TestUnicodeEdgeCases()
+        {
+            // Test surrogate pairs - high surrogate
+            var cmd = "show \"\\uD83D\"";
+            var args = CommandTokenizer.Tokenize(cmd);
+            Assert.AreEqual(3, args.Count);
+            Assert.AreEqual("show", args[0].Value);
+            Assert.AreEqual(" ", args[1].Value);
+            Assert.AreEqual("\uD83D", args[2].Value); // High surrogate
+
+            // Test surrogate pairs - low surrogate
+            cmd = "show \"\\uDE00\"";
+            args = CommandTokenizer.Tokenize(cmd);
+            Assert.AreEqual(3, args.Count);
+            Assert.AreEqual("show", args[0].Value);
+            Assert.AreEqual(" ", args[1].Value);
+            Assert.AreEqual("\uDE00", args[2].Value); // Low surrogate
+
+            // Test null character
+            cmd = "show \"\\u0000\"";
+            args = CommandTokenizer.Tokenize(cmd);
+            Assert.AreEqual(3, args.Count);
+            Assert.AreEqual("show", args[0].Value);
+            Assert.AreEqual(" ", args[1].Value);
+            Assert.AreEqual("\u0000", args[2].Value); // Null character
+
+            // Test maximum Unicode value
+            cmd = "show \"\\uFFFF\"";
+            args = CommandTokenizer.Tokenize(cmd);
+            Assert.AreEqual(3, args.Count);
+            Assert.AreEqual("show", args[0].Value);
+            Assert.AreEqual(" ", args[1].Value);
+            Assert.AreEqual("\uFFFF", args[2].Value); // Maximum Unicode value
+
+            // Test multiple Unicode escapes in sequence
+            cmd = "show \"\\u0048\\u0065\\u006C\\u006C\\u006F\\u0020\\u0057\\u006F\\u0072\\u006C\\u0064\"";
+            args = CommandTokenizer.Tokenize(cmd);
+            Assert.AreEqual(3, args.Count);
+            Assert.AreEqual("show", args[0].Value);
+            Assert.AreEqual(" ", args[1].Value);
+            Assert.AreEqual("Hello World", args[2].Value);
+
+            // Test Unicode escape mixed with regular characters
+            cmd = "show \"Hello\\u0020World\"";
+            args = CommandTokenizer.Tokenize(cmd);
+            Assert.AreEqual(3, args.Count);
+            Assert.AreEqual("show", args[0].Value);
+            Assert.AreEqual(" ", args[1].Value);
+            Assert.AreEqual("Hello World", args[2].Value);
+        }
     }
 }