Add unidiff text rendering support (fixes #147)

Author: mmanela

.vscode/settings.json

@@ -1,3 +1,6 @@
 {
     "dotnet-test-explorer.testProjectPath": "Facts.DiffPlex",
+    "cSpell.words": [
+        "Xunit"
+    ],
 }

DiffPlex.ConsoleRunner/Program.cs

@@ -1,39 +1,99 @@
 using System;
+using System.IO;
 using DiffPlex.DiffBuilder;
 using DiffPlex.DiffBuilder.Model;
 using DiffPlex.Model;
+using DiffPlex.Renderer;
 
 namespace DiffPlex.ConsoleRunner;
 
 internal static class Program
 {
-    private static void Main()
+    private static void Main(string[] args)
     {
-        var diffBuilder = new InlineDiffBuilder(new Differ());
-        var diff = diffBuilder.BuildDiffModel(TestData.OldText, TestData.NewText);
+        if (args.Length < 3)
+        {
+            PrintUsage();
+            return;
+        }
 
-        foreach (var line in diff.Lines)
+        try
         {
-            Console.ForegroundColor = ConsoleColor.Blue;
-            if (line.Position.HasValue) Console.Write(line.Position.Value);
-            Console.Write('\t');
-            switch (line.Type)
+            string command = args[0].ToLowerInvariant();
+            string result;
+
+            if (command == "file")
+            {
+                // File comparison mode
+                string oldFilePath = NormalizePath(args[1]);
+                string newFilePath = NormalizePath(args[2]);
+                
+                if (!File.Exists(oldFilePath))
+                {
+                    Console.Error.WriteLine($"Error: File not found: {oldFilePath}");
+                    return;
+                }
+
+                if (!File.Exists(newFilePath))
+                {
+                    Console.Error.WriteLine($"Error: File not found: {newFilePath}");
+                    return;
+                }
+
+                string oldText = File.ReadAllText(oldFilePath);
+                string newText = File.ReadAllText(newFilePath);
+                result = UnidiffRenderer.GenerateUnidiff(oldText, newText, oldFilePath, newFilePath);
+            }
+            else if (command == "text")
+            {
+                // Text comparison mode
+                // Process escape sequences like \n in the input text
+                string oldText = args[1].Replace("\\n", "\n");
+                string newText = args[2].Replace("\\n", "\n");
+                result = UnidiffRenderer.GenerateUnidiff(oldText, newText);
+            }
+            else
             {
-                case ChangeType.Inserted:
-                    Console.ForegroundColor = ConsoleColor.Green;
-                    Console.Write("+ ");
-                    break;
-                case ChangeType.Deleted:
-                    Console.ForegroundColor = ConsoleColor.Red;
-                    Console.Write("- ");
-                    break;
-                default:
-                    Console.ForegroundColor = ConsoleColor.White;
-                    Console.Write("  ");
-                    break;
+                Console.Error.WriteLine($"Unknown command: {command}");
+                PrintUsage();
+                return;
             }
 
-            Console.WriteLine(line.Text);
+            Console.WriteLine(result);
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"Error: {ex.Message}");
         }
     }
+
+    private static void PrintUsage()
+    {
+        Console.WriteLine("DiffPlex.ConsoleRunner - Generate unified diff (unidiff) output");
+        Console.WriteLine();
+        Console.WriteLine("Usage:");
+        Console.WriteLine("  DiffPlex.ConsoleRunner file <old-file> <new-file>");
+        Console.WriteLine("  DiffPlex.ConsoleRunner text <old-string> <new-string>");
+        Console.WriteLine();
+        Console.WriteLine("Commands:");
+        Console.WriteLine("  file    Compare two files and generate a unidiff");
+        Console.WriteLine("  text    Compare two strings and generate a unidiff");
+        Console.WriteLine();
+        Console.WriteLine("File paths work with both Windows and Unix-style paths.");
+    }
+    
+    /// <summary>
+    /// Normalizes a file path to work correctly on both Windows and Unix-based systems.
+    /// </summary>
+    /// <param name="path">The path to normalize.</param>
+    /// <returns>A normalized path that works on the current operating system.</returns>
+    private static string NormalizePath(string path)
+    {
+        if (string.IsNullOrWhiteSpace(path))
+            return path;
+            
+        // Replace any forward slashes with the platform-specific directory separator
+        return path.Replace('/', Path.DirectorySeparatorChar)
+                  .Replace('\\', Path.DirectorySeparatorChar);
+    }
 }

DiffPlex/DiffPlex.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <Import Project="..\NuGet.props" />
   <PropertyGroup>
-    <TargetFrameworks>net45;netstandard1.0;netstandard2.0;net6.0</TargetFrameworks>
+    <TargetFrameworks>net45;netstandard2.0;net6.0</TargetFrameworks>
     <Version>1.7.2</Version>
     <PackageTags>diff</PackageTags>
     <Description>DiffPlex is a diffing library that allows you to programmatically create text diffs. DiffPlex is a fast and tested library.</Description>