Add various exception improvements

docs/input/exceptions.md

@@ -9,9 +9,9 @@ You can make exception a bit more readable by using the `WriteException` method.
 AnsiConsole.WriteException(ex);
 ```
 
-<img src="assets/images/exception.png" style="max-width: 100%; margin-bottom: 20px">
-
+<img src="assets/images/exception.png" style="max-width: 100%;">
 
+## Shortening parts
 
 You can also shorten specific parts of the exception to make it even
 more readable, and make paths clickable hyperlinks. Whether or not
@@ -24,3 +24,29 @@ AnsiConsole.WriteException(ex,
 ```
 
 <img src="assets/images/compact_exception.png" style="max-width: 100%;">
+
+## Customizing exception output
+
+In addition to shorten specific part of the exception, you can 
+also override the default styling.
+
+```csharp
+AnsiConsole.WriteException(ex, new ExceptionSettings
+{
+    Format = ExceptionFormats.ShortenEverything | ExceptionFormats.ShowLinks,
+    Style = new ExceptionStyle
+    {
+        Exception = Style.WithForeground(Color.Grey),
+        Message = Style.WithForeground(Color.White),
+        NonEmphasized = Style.WithForeground(Color.Cornsilk1),
+        Parenthesis = Style.WithForeground(Color.Cornsilk1),
+        Method = Style.WithForeground(Color.Red),
+        ParameterName = Style.WithForeground(Color.Cornsilk1),
+        ParameterType = Style.WithForeground(Color.Red),
+        Path = Style.WithForeground(Color.Red),
+        LineNumber = Style.WithForeground(Color.Cornsilk1),
+    }
+});
+```
+
+<img src="assets/images/custom_exception.png" style="max-width: 100%;">

docs/input/markup.md

@@ -43,6 +43,12 @@ AnsiConsole.Markup("[[Hello]] "); // [Hello]
 AnsiConsole.Markup("[red][[World]][/]"); // [World]
 ```
 
+You can also use the `SafeMarkup` extension method.
+
+```csharp
+AnsiConsole.Markup("[red]{0}[/]", "Hello [World]".SafeMarkup());
+```
+
 # Setting background color
 
 You can set the background color in markup by prefixing the color with

examples/Exceptions/Program.cs

@@ -14,11 +14,35 @@ namespace Exceptions
             }
             catch (Exception ex)
             {
+                AnsiConsole.WriteLine();
+                AnsiConsole.Render(new Panel("[u]Default[/]").Expand());
                 AnsiConsole.WriteLine();
                 AnsiConsole.WriteException(ex);
 
+                AnsiConsole.WriteLine();
+                AnsiConsole.Render(new Panel("[u]Compact[/]").Expand());
                 AnsiConsole.WriteLine();
                 AnsiConsole.WriteException(ex, ExceptionFormats.ShortenEverything | ExceptionFormats.ShowLinks);
+
+                AnsiConsole.WriteLine();
+                AnsiConsole.Render(new Panel("[u]Custom colors[/]").Expand());
+                AnsiConsole.WriteLine();
+                AnsiConsole.WriteException(ex, new ExceptionSettings
+                {
+                    Format = ExceptionFormats.ShortenEverything | ExceptionFormats.ShowLinks,
+                    Style = new ExceptionStyle
+                    {
+                        Exception = Style.WithForeground(Color.Grey),
+                        Message = Style.WithForeground(Color.White),
+                        NonEmphasized = Style.WithForeground(Color.Cornsilk1),
+                        Parenthesis = Style.WithForeground(Color.Cornsilk1),
+                        Method = Style.WithForeground(Color.Red),
+                        ParameterName = Style.WithForeground(Color.Cornsilk1),
+                        ParameterType = Style.WithForeground(Color.Red),
+                        Path = Style.WithForeground(Color.Red),
+                        LineNumber = Style.WithForeground(Color.Cornsilk1),
+                    }
+                });
             }
         }
 

src/Spectre.Console.Tests/Unit/ColorTests.cs

@@ -228,6 +228,39 @@ namespace Spectre.Console.Tests.Unit
             }
         }
 
+        public sealed class TheToMarkupMethod
+        {
+            [Fact]
+            public void Should_Return_Expected_Markup_For_Default_Color()
+            {
+                // Given, When
+                var result = Color.Default.ToMarkup();
+
+                // Then
+                result.ShouldBe("default");
+            }
+
+            [Fact]
+            public void Should_Return_Expected_Markup_For_Known_Color()
+            {
+                // Given, When
+                var result = Color.Red.ToMarkup();
+
+                // Then
+                result.ShouldBe("red");
+            }
+
+            [Fact]
+            public void Should_Return_Expected_Markup_For_Custom_Color()
+            {
+                // Given, When
+                var result = new Color(255, 1, 12).ToMarkup();
+
+                // Then
+                result.ShouldBe("#FF010C");
+            }
+        }
+
         public sealed class TheToStringMethod
         {
             [Fact]

src/Spectre.Console.Tests/Unit/StyleTests.cs

@@ -317,5 +317,60 @@ namespace Spectre.Console.Tests.Unit
                 result.ShouldBeFalse();
             }
         }
+
+        public sealed class TheToMarkupMethod
+        {
+            [Fact]
+            public void Should_Return_Expected_Markup_For_Style_With_Foreground_Color()
+            {
+                // Given
+                var style = new Style(Color.Red);
+
+                // When
+                var result = style.ToMarkup();
+
+                // Then
+                result.ShouldBe("red");
+            }
+
+            [Fact]
+            public void Should_Return_Expected_Markup_For_Style_With_Foreground_And_Background_Color()
+            {
+                // Given
+                var style = new Style(Color.Red, Color.Green);
+
+                // When
+                var result = style.ToMarkup();
+
+                // Then
+                result.ShouldBe("red on green");
+            }
+
+            [Fact]
+            public void Should_Return_Expected_Markup_For_Style_With_Foreground_And_Background_Color_And_Decoration()
+            {
+                // Given
+                var style = new Style(Color.Red, Color.Green, Decoration.Bold | Decoration.Underline);
+
+                // When
+                var result = style.ToMarkup();
+
+                // Then
+                result.ShouldBe("bold underline red on green");
+            }
+
+            [Fact]
+            public void Should_Return_Expected_Markup_For_Style_With_Only_Background_Color()
+            {
+                // Given
+                var style = new Style(background: Color.Green);
+
+                // When
+                var result = style.ToMarkup();
+
+                // Then
+                result.ShouldBe("default on green");
+            }
+        }
     }
 }

src/Spectre.Console/AnsiConsole.Exceptions.cs

@@ -16,5 +16,15 @@ namespace Spectre.Console
         {
             Console.WriteException(exception, format);
         }
+
+        /// <summary>
+        /// Writes an exception to the console.
+        /// </summary>
+        /// <param name="exception">The exception to write to the console.</param>
+        /// <param name="settings">The exception settings.</param>
+        public static void WriteException(Exception exception, ExceptionSettings settings)
+        {
+            Console.WriteException(exception, settings);
+        }
     }
 }

src/Spectre.Console/Color.cs

@@ -249,8 +249,13 @@ namespace Spectre.Console
         /// Converts the color to a markup string.
         /// </summary>
         /// <returns>A <see cref="string"/> representing the color as markup.</returns>
-        public string ToMarkupString()
+        public string ToMarkup()
         {
+            if (IsDefault)
+            {
+                return "default";
+            }
+
             if (Number != null)
             {
                 var name = ColorTable.GetName(Number.Value);

src/Spectre.Console/ExceptionSettings.cs

@@ -0,0 +1,27 @@
+namespace Spectre.Console
+{
+    /// <summary>
+    /// Exception settings.
+    /// </summary>
+    public sealed class ExceptionSettings
+    {
+        /// <summary>
+        /// Gets or sets the exception format.
+        /// </summary>
+        public ExceptionFormats Format { get; set; }
+
+        /// <summary>
+        /// Gets or sets the exception style.
+        /// </summary>
+        public ExceptionStyle Style { get; set; }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="ExceptionSettings"/> class.
+        /// </summary>
+        public ExceptionSettings()
+        {
+            Format = ExceptionFormats.Default;
+            Style = new ExceptionStyle();
+        }
+    }
+}

src/Spectre.Console/ExceptionStyle.cs

@@ -0,0 +1,58 @@
+namespace Spectre.Console
+{
+    /// <summary>
+    /// Represent an exception style.
+    /// </summary>
+    public sealed class ExceptionStyle
+    {
+        /// <summary>
+        /// Gets or sets the message color.
+        /// </summary>
+        public Style Message { get; set; } = new Style(Color.Red, Color.Default, Decoration.Bold);
+
+        /// <summary>
+        /// Gets or sets the exception color.
+        /// </summary>
+        public Style Exception { get; set; } = new Style(Color.White);
+
+        /// <summary>
+        /// Gets or sets the method color.
+        /// </summary>
+        public Style Method { get; set; } = new Style(Color.Yellow);
+
+        /// <summary>
+        /// Gets or sets the parameter type color.
+        /// </summary>
+        public Style ParameterType { get; set; } = new Style(Color.Blue);
+
+        /// <summary>
+        /// Gets or sets the parameter name color.
+        /// </summary>
+        public Style ParameterName { get; set; } = new Style(Color.Silver);
+
+        /// <summary>
+        /// Gets or sets the parenthesis color.
+        /// </summary>
+        public Style Parenthesis { get; set; } = new Style(Color.Silver);
+
+        /// <summary>
+        /// Gets or sets the path color.
+        /// </summary>
+        public Style Path { get; set; } = new Style(Color.Yellow, Color.Default, Decoration.Bold);
+
+        /// <summary>
+        /// Gets or sets the line number color.
+        /// </summary>
+        public Style LineNumber { get; set; } = new Style(Color.Blue);
+
+        /// <summary>
+        /// Gets or sets the color for dimmed text such as "at" or "in".
+        /// </summary>
+        public Style Dimmed { get; set; } = new Style(Color.Grey);
+
+        /// <summary>
+        /// Gets or sets the color for non emphasized items.
+        /// </summary>
+        public Style NonEmphasized { get; set; } = new Style(Color.Silver);
+    }
+}

src/Spectre.Console/Extensions/AnsiConsoleExtensions.Exceptions.cs

@@ -17,5 +17,16 @@ namespace Spectre.Console
         {
             Render(console, exception.GetRenderable(format));
         }
+
+        /// <summary>
+        /// Writes an exception to the console.
+        /// </summary>
+        /// <param name="console">The console.</param>
+        /// <param name="exception">The exception to write to the console.</param>
+        /// <param name="settings">The exception settings.</param>
+        public static void WriteException(this IAnsiConsole console, Exception exception, ExceptionSettings settings)
+        {
+            Render(console, exception.GetRenderable(settings));
+        }
     }
 }

src/Spectre.Console/Extensions/ExceptionExtensions.cs

@@ -16,7 +16,36 @@ namespace Spectre.Console
         /// <returns>A <see cref="IRenderable"/> representing the exception.</returns>
         public static IRenderable GetRenderable(this Exception exception, ExceptionFormats format = ExceptionFormats.Default)
         {
-            return ExceptionFormatter.Format(exception, format);
+            if (exception is null)
+            {
+                throw new ArgumentNullException(nameof(exception));
+            }
+
+            return GetRenderable(exception, new ExceptionSettings
+            {
+                Format = format,
+            });
+        }
+
+        /// <summary>
+        /// Gets a <see cref="IRenderable"/> representation of the exception.
+        /// </summary>
+        /// <param name="exception">The exception to format.</param>
+        /// <param name="settings">The exception settings.</param>
+        /// <returns>A <see cref="IRenderable"/> representing the exception.</returns>
+        public static IRenderable GetRenderable(this Exception exception, ExceptionSettings settings)
+        {
+            if (exception is null)
+            {
+                throw new ArgumentNullException(nameof(exception));
+            }
+
+            if (settings is null)
+            {
+                throw new ArgumentNullException(nameof(settings));
+            }
+
+            return ExceptionFormatter.Format(exception, settings);
         }
     }
 }

src/Spectre.Console/Internal/DecorationTable.cs

@@ -1,12 +1,14 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
+using System.Linq;
 
 namespace Spectre.Console.Internal
 {
     internal static class DecorationTable
     {
         private static readonly Dictionary<string, Decoration?> _lookup;
+        private static readonly Dictionary<Decoration, string> _reverseLookup;
 
         [SuppressMessage("Performance", "CA1810:Initialize reference type static fields inline")]
         static DecorationTable()
@@ -28,6 +30,21 @@ namespace Spectre.Console.Internal
                 { "strikethrough", Decoration.Strikethrough },
                 { "s", Decoration.Strikethrough },
             };
+
+            _reverseLookup = new Dictionary<Decoration, string>();
+            foreach (var (name, decoration) in _lookup)
+            {
+                // Cannot happen, but the compiler thinks so...
+                if (decoration == null)
+                {
+                    continue;
+                }
+
+                if (!_reverseLookup.ContainsKey(decoration.Value))
+                {
+                    _reverseLookup[decoration.Value] = name;
+                }
+            }
         }
 
         public static Decoration? GetDecoration(string name)
@@ -35,5 +52,23 @@ namespace Spectre.Console.Internal
             _lookup.TryGetValue(name, out var result);
             return result;
         }
+
+        public static List<string> GetMarkupNames(Decoration decoration)
+        {
+            var result = new List<string>();
+
+            Enum.GetValues(typeof(Decoration))
+                .Cast<Decoration>()
+                .Where(flag => (decoration & flag) != 0)
+                .ForEach(flag =>
+                {
+                    if (flag != Decoration.None && _reverseLookup.TryGetValue(flag, out var name))
+                    {
+                        result.Add(name);
+                    }
+                });
+
+            return result;
+        }
     }
 }

src/Spectre.Console/Internal/ExceptionFormatter.cs

@@ -8,13 +8,7 @@ namespace Spectre.Console
 {
     internal static class ExceptionFormatter
     {
-        private static readonly Color _typeColor = Color.White;
-        private static readonly Color _methodColor = Color.Yellow;
-        private static readonly Color _parameterColor = Color.Blue;
-        private static readonly Color _pathColor = Color.Yellow;
-        private static readonly Color _dimmedColor = Color.Grey;
-
-        public static IRenderable Format(Exception exception, ExceptionFormats format)
+        public static IRenderable Format(Exception exception, ExceptionSettings settings)
         {
             if (exception is null)
             {
@@ -27,10 +21,10 @@ namespace Spectre.Console
                 return new Text(exception.ToString());
             }
 
-            return GetException(info, format);
+            return GetException(info, settings);
         }
 
-        private static IRenderable GetException(ExceptionInfo info, ExceptionFormats format)
+        private static IRenderable GetException(ExceptionInfo info, ExceptionSettings settings)
         {
             if (info is null)
             {
@@ -39,20 +33,20 @@ namespace Spectre.Console
 
             return new Rows(new IRenderable[]
             {
-                GetMessage(info, format),
-                GetStackFrames(info, format),
+                GetMessage(info, settings),
+                GetStackFrames(info, settings),
             }).Expand();
         }
 
-        private static Markup GetMessage(ExceptionInfo ex, ExceptionFormats format)
+        private static Markup GetMessage(ExceptionInfo ex, ExceptionSettings settings)
         {
-            var shortenTypes = (format & ExceptionFormats.ShortenTypes) != 0;
-            var type = Emphasize(ex.Type, new[] { '.' }, _typeColor.ToMarkupString(), shortenTypes);
-            var message = $"[b red]{ex.Message.SafeMarkup()}[/]";
+            var shortenTypes = (settings.Format & ExceptionFormats.ShortenTypes) != 0;
+            var type = Emphasize(ex.Type, new[] { '.' }, settings.Style.Exception, shortenTypes, settings);
+            var message = $"[{settings.Style.Message.ToMarkup()}]{ex.Message.SafeMarkup()}[/]";
             return new Markup(string.Concat(type, ": ", message));
         }
 
-        private static Grid GetStackFrames(ExceptionInfo ex, ExceptionFormats format)
+        private static Grid GetStackFrames(ExceptionInfo ex, ExceptionSettings settings)
         {
             var grid = new Grid();
             grid.AddColumn(new GridColumn().PadLeft(2).PadRight(0).NoWrap());
@@ -63,7 +57,7 @@ namespace Spectre.Console
             {
                 grid.AddRow(
                     Text.Empty,
-                    GetException(ex.Inner, format));
+                    GetException(ex.Inner, settings));
             }
 
             // Stack frames
@@ -72,47 +66,57 @@ namespace Spectre.Console
                 var builder = new StringBuilder();
 
                 // Method
-                var shortenMethods = (format & ExceptionFormats.ShortenMethods) != 0;
-                builder.Append(Emphasize(frame.Method, new[] { '.' }, _methodColor.ToMarkupString(), shortenMethods));
-                builder.Append('(');
-                builder.Append(string.Join(", ", frame.Parameters.Select(x => $"[{_parameterColor.ToMarkupString()}]{x.Type.SafeMarkup()}[/] {x.Name}")));
-                builder.Append(')');
+                var shortenMethods = (settings.Format & ExceptionFormats.ShortenMethods) != 0;
+                builder.Append(Emphasize(frame.Method, new[] { '.' }, settings.Style.Method, shortenMethods, settings));
+                builder.Append('[').Append(settings.Style.Parenthesis.ToMarkup()).Append(']').Append('(').Append("[/]");
+                AppendParameters(builder, frame, settings);
+                builder.Append('[').Append(settings.Style.Parenthesis.ToMarkup()).Append(']').Append(')').Append("[/]");
 
                 if (frame.Path != null)
                 {
-                    builder.Append(" [").Append(_dimmedColor.ToMarkupString()).Append("]in[/] ");
+                    builder.Append(" [").Append(settings.Style.Dimmed.ToMarkup()).Append("]in[/] ");
 
                     // Path
-                    AppendPath(builder, frame, format);
+                    AppendPath(builder, frame, settings);
 
                     // Line number
                     if (frame.LineNumber != null)
                     {
-                        builder.Append(':');
-                        builder.Append('[').Append(_parameterColor.ToMarkupString()).Append(']').Append(frame.LineNumber).Append("[/]");
+                        builder.Append('[').Append(settings.Style.Dimmed.ToMarkup()).Append("]:[/]");
+                        builder.Append('[').Append(settings.Style.LineNumber.ToMarkup()).Append(']').Append(frame.LineNumber).Append("[/]");
                     }
                 }
 
-                grid.AddRow($"[{_dimmedColor.ToMarkupString()}]at[/]", builder.ToString());
+                grid.AddRow(
+                    $"[{settings.Style.Dimmed.ToMarkup()}]at[/]",
+                    builder.ToString());
             }
 
             return grid;
         }
 
-        private static void AppendPath(StringBuilder builder, StackFrameInfo frame, ExceptionFormats format)
+        private static void AppendParameters(StringBuilder builder, StackFrameInfo frame, ExceptionSettings settings)
+        {
+            var typeColor = settings.Style.ParameterType.ToMarkup();
+            var nameColor = settings.Style.ParameterName.ToMarkup();
+            var parameters = frame.Parameters.Select(x => $"[{typeColor}]{x.Type.SafeMarkup()}[/] [{nameColor}]{x.Name}[/]");
+            builder.Append(string.Join(", ", parameters));
+        }
+
+        private static void AppendPath(StringBuilder builder, StackFrameInfo frame, ExceptionSettings settings)
         {
             if (frame?.Path is null)
             {
                 return;
             }
 
-            void RenderLink()
+            void AppendPath()
             {
-                var shortenPaths = (format & ExceptionFormats.ShortenPaths) != 0;
-                builder.Append(Emphasize(frame.Path, new[] { '/', '\\' }, $"b {_pathColor.ToMarkupString()}", shortenPaths));
+                var shortenPaths = (settings.Format & ExceptionFormats.ShortenPaths) != 0;
+                builder.Append(Emphasize(frame.Path, new[] { '/', '\\' }, settings.Style.Path, shortenPaths, settings));
             }
 
-            if ((format & ExceptionFormats.ShowLinks) != 0)
+            if ((settings.Format & ExceptionFormats.ShowLinks) != 0)
             {
                 var hasLink = frame.TryGetUri(out var uri);
                 if (hasLink && uri != null)
@@ -120,7 +124,7 @@ namespace Spectre.Console
                     builder.Append("[link=").Append(uri.AbsoluteUri).Append(']');
                 }
 
-                RenderLink();
+                AppendPath();
 
                 if (hasLink && uri != null)
                 {
@@ -129,11 +133,11 @@ namespace Spectre.Console
             }
             else
             {
-                RenderLink();
+                AppendPath();
             }
         }
 
-        private static string Emphasize(string input, char[] separators, string color, bool compact)
+        private static string Emphasize(string input, char[] separators, Style color, bool compact, ExceptionSettings settings)
         {
             var builder = new StringBuilder();
 
@@ -143,10 +147,12 @@ namespace Spectre.Console
             {
                 if (!compact)
                 {
-                    builder.Append("[silver]").Append(type, 0, index + 1).Append("[/]");
+                    builder.Append('[').Append(settings.Style.NonEmphasized.ToMarkup()).Append(']')
+                        .Append(type, 0, index + 1).Append("[/]");
                 }
 
-                builder.Append('[').Append(color).Append(']').Append(type, index + 1, type.Length - index - 1).Append("[/]");
+                builder.Append('[').Append(color.ToMarkup()).Append(']')
+                    .Append(type, index + 1, type.Length - index - 1).Append("[/]");
             }
             else
             {

src/Spectre.Console/Internal/Extensions/DictionaryExtensions.cs

@@ -0,0 +1,13 @@
+using System.Collections.Generic;
+
+namespace Spectre.Console.Internal
+{
+    internal static class DictionaryExtensions
+    {
+        public static void Deconstruct<T1, T2>(this KeyValuePair<T1, T2> tuple, out T1 key, out T2 value)
+        {
+            key = tuple.Key;
+            value = tuple.Value;
+        }
+    }
+}

src/Spectre.Console/Style.cs

@@ -1,5 +1,7 @@
 using System;
+using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
+using System.Linq;
 using Spectre.Console.Internal;
 
 namespace Spectre.Console
@@ -25,7 +27,7 @@ namespace Spectre.Console
         public Decoration Decoration { get; }
 
         /// <summary>
-        /// Gets the link.
+        /// Gets the link associated with the style.
         /// </summary>
         public string? Link { get; }
 
@@ -191,6 +193,41 @@ namespace Spectre.Console
             }
         }
 
+        /// <summary>
+        /// Returns the markup representation of this style.
+        /// </summary>
+        /// <returns>The markup representation of this style.</returns>
+        public string ToMarkup()
+        {
+            var builder = new List<string>();
+
+            if (Decoration != Decoration.None)
+            {
+                var result = DecorationTable.GetMarkupNames(Decoration);
+                if (result.Count != 0)
+                {
+                    builder.AddRange(result);
+                }
+            }
+
+            if (Foreground != Color.Default)
+            {
+                builder.Add(Foreground.ToMarkup());
+            }
+
+            if (Background != Color.Default)
+            {
+                if (builder.Count == 0)
+                {
+                    builder.Add("default");
+                }
+
+                builder.Add("on " + Background.ToMarkup());
+            }
+
+            return string.Join(" ", builder);
+        }
+
         /// <inheritdoc/>
         public override bool Equals(object? obj)
         {