Add support for arrays in [DefaultValue] attributes (#1164)

Fixes #1163

src/Spectre.Console.Cli/Internal/Binding/CommandValueBinder.cs

@@ -65,6 +65,11 @@ internal sealed class CommandValueBinder
 
     private object GetArray(CommandParameter parameter, object? value)
     {
+        if (value is Array)
+        {
+            return value;
+        }
+
         // Add a new item to the array
         var array = (Array?)_lookup.GetValue(parameter);
         Array newArray;

src/Spectre.Console.Cli/Internal/Binding/CommandValueResolver.cs

@@ -133,13 +133,33 @@ internal static class CommandValueResolver
             var (converter, _) = GetConverter(lookup, binder, resolver, parameter);
             if (converter != null)
             {
-                result = converter.ConvertFrom(result);
+                result = result is Array array ? ConvertArray(array, converter) : converter.ConvertFrom(result);
             }
         }
 
         return result;
     }
 
+    private static Array ConvertArray(Array sourceArray, TypeConverter converter)
+    {
+        Array? targetArray = null;
+        for (var i = 0; i < sourceArray.Length; i++)
+        {
+            var item = sourceArray.GetValue(i);
+            if (item != null)
+            {
+                var converted = converter.ConvertFrom(item);
+                if (converted != null)
+                {
+                    targetArray ??= Array.CreateInstance(converted.GetType(), sourceArray.Length);
+                    targetArray.SetValue(converted, i);
+                }
+            }
+        }
+
+        return targetArray ?? sourceArray;
+    }
+
     [SuppressMessage("Style", "IDE0019:Use pattern matching", Justification = "It's OK")]
     private static (TypeConverter? Converter, ConstructorInfo? StringConstructor) GetConverter(CommandValueLookup lookup, CommandValueBinder binder, ITypeResolver resolver, CommandParameter parameter)
     {

src/Spectre.Console.Cli/Internal/HelpWriter.cs

@@ -348,7 +348,17 @@ internal static class HelpWriter
             var columns = new List<string> { GetOptionParts(option) };
             if (defaultValueColumn)
             {
-                columns.Add(option.DefaultValue == null ? " " : $"[bold]{option.DefaultValue.ToString().EscapeMarkup()}[/]");
+                static string Bold(object obj) => $"[bold]{obj.ToString().EscapeMarkup()}[/]";
+
+                var defaultValue = option.DefaultValue switch
+                {
+                    null => " ",
+                    "" => " ",
+                    Array { Length: 0 } => " ",
+                    Array array => string.Join(", ", array.Cast<object>().Select(Bold)),
+                    _ => Bold(option.DefaultValue),
+                };
+                columns.Add(defaultValue);
             }
 
             columns.Add(option.Description?.TrimEnd('.') ?? " ");

test/Spectre.Console.Cli.Tests/Data/Settings/LionSettings.cs

@@ -9,4 +9,9 @@ public class LionSettings : CatSettings
     [CommandOption("-c <CHILDREN>")]
     [Description("The number of children the lion has.")]
     public int Children { get; set; }
+
+    [CommandOption("-d <DAY>")]
+    [Description("The days the lion goes hunting.")]
+    [DefaultValue(new[] { DayOfWeek.Monday, DayOfWeek.Thursday })]
+    public DayOfWeek[] HuntDays { get; set; }
 }

test/Spectre.Console.Cli.Tests/Data/Settings/OptionalArgumentWithDefaultValueSettings.cs

@@ -33,3 +33,18 @@ public sealed class RequiredArgumentWithDefaultValueSettings : CommandSettings
     [DefaultValue("Hello World")]
     public string Greeting { get; set; }
 }
+
+public sealed class OptionWithArrayOfEnumDefaultValueSettings : CommandSettings
+{
+    [CommandOption("--days")]
+    [DefaultValue(new[] { DayOfWeek.Sunday, DayOfWeek.Saturday })]
+    public DayOfWeek[] Days { get; set; }
+}
+
+public sealed class OptionWithArrayOfStringDefaultValueAndTypeConverterSettings : CommandSettings
+{
+    [CommandOption("--numbers")]
+    [DefaultValue(new[] { "2", "3" })]
+    [TypeConverter(typeof(StringToIntegerConverter))]
+    public int[] Numbers { get; set; }
+}

test/Spectre.Console.Cli.Tests/Expectations/Help/Default.Output.verified.txt

@@ -10,8 +10,9 @@ ARGUMENTS:
 
 OPTIONS:
                              DEFAULT
-    -h, --help                          Prints help information
+    -h, --help                                   Prints help information
-    -a, --alive                         Indicates whether or not the animal is alive
+    -a, --alive                                  Indicates whether or not the animal is alive
     -n, --name <VALUE>
-        --agility <VALUE>    10         The agility between 0 and 100
+        --agility <VALUE>    10                  The agility between 0 and 100
-    -c <CHILDREN>                       The number of children the lion has
+    -c <CHILDREN>                                The number of children the lion has
+    -d <DAY>                 Monday, Thursday    The days the lion goes hunting

test/Spectre.Console.Cli.Tests/Expectations/Help/DefaultExamples.Output.verified.txt

@@ -13,8 +13,9 @@ ARGUMENTS:
 
 OPTIONS:
                              DEFAULT
-    -h, --help                          Prints help information
+    -h, --help                                   Prints help information
-    -a, --alive                         Indicates whether or not the animal is alive
+    -a, --alive                                  Indicates whether or not the animal is alive
     -n, --name <VALUE>
-        --agility <VALUE>    10         The agility between 0 and 100
+        --agility <VALUE>    10                  The agility between 0 and 100
-    -c <CHILDREN>                       The number of children the lion has
+    -c <CHILDREN>                                The number of children the lion has
+    -d <DAY>                 Monday, Thursday    The days the lion goes hunting

test/Spectre.Console.Cli.Tests/Expectations/Help/Default_Without_Args.Output.verified.txt

@@ -10,8 +10,9 @@ ARGUMENTS:
 
 OPTIONS:
                              DEFAULT
-    -h, --help                          Prints help information
+    -h, --help                                   Prints help information
-    -a, --alive                         Indicates whether or not the animal is alive
+    -a, --alive                                  Indicates whether or not the animal is alive
     -n, --name <VALUE>
-        --agility <VALUE>    10         The agility between 0 and 100
+        --agility <VALUE>    10                  The agility between 0 and 100
-    -c <CHILDREN>                       The number of children the lion has
+    -c <CHILDREN>                                The number of children the lion has
+    -d <DAY>                 Monday, Thursday    The days the lion goes hunting

test/Spectre.Console.Cli.Tests/Expectations/Help/Default_Without_Args_Additional.Output.verified.txt

@@ -10,11 +10,12 @@ ARGUMENTS:
 
 OPTIONS:
                              DEFAULT
-    -h, --help                          Prints help information
+    -h, --help                                   Prints help information
-    -a, --alive                         Indicates whether or not the animal is alive
+    -a, --alive                                  Indicates whether or not the animal is alive
     -n, --name <VALUE>
-        --agility <VALUE>    10         The agility between 0 and 100
+        --agility <VALUE>    10                  The agility between 0 and 100
-    -c <CHILDREN>                       The number of children the lion has
+    -c <CHILDREN>                                The number of children the lion has
+    -d <DAY>                 Monday, Thursday    The days the lion goes hunting
 
 COMMANDS:
     giraffe <LENGTH>    The giraffe command

test/Spectre.Console.Cli.Tests/Expectations/Help/Leaf.Output.verified.txt

@@ -8,5 +8,7 @@ ARGUMENTS:
     <TEETH>    The number of teeth the lion has
 
 OPTIONS:
-    -h, --help       Prints help information
+                     DEFAULT
-    -c <CHILDREN>    The number of children the lion has
+    -h, --help                           Prints help information
+    -c <CHILDREN>                        The number of children the lion has
+    -d <DAY>         Monday, Thursday    The days the lion goes hunting

test/Spectre.Console.Cli.Tests/Unit/CommandAppTests.cs

@@ -396,6 +396,50 @@ public sealed partial class CommandAppTests
         });
     }
 
+    [Fact]
+    public void Should_Assign_Array_Default_Value_To_Command_Option()
+    {
+        // Given
+        var app = new CommandAppTester();
+        app.SetDefaultCommand<GenericCommand<OptionWithArrayOfEnumDefaultValueSettings>>();
+        app.Configure(config =>
+        {
+            config.PropagateExceptions();
+        });
+
+        // When
+        var result = app.Run(Array.Empty<string>());
+
+        // Then
+        result.ExitCode.ShouldBe(0);
+        result.Settings.ShouldBeOfType<OptionWithArrayOfEnumDefaultValueSettings>().And(settings =>
+        {
+            settings.Days.ShouldBe(new[] { DayOfWeek.Sunday, DayOfWeek.Saturday });
+        });
+    }
+
+    [Fact]
+    public void Should_Assign_Array_Default_Value_To_Command_Option_Using_Converter_If_Necessary()
+    {
+        // Given
+        var app = new CommandAppTester();
+        app.SetDefaultCommand<GenericCommand<OptionWithArrayOfStringDefaultValueAndTypeConverterSettings>>();
+        app.Configure(config =>
+        {
+            config.PropagateExceptions();
+        });
+
+        // When
+        var result = app.Run(Array.Empty<string>());
+
+        // Then
+        result.ExitCode.ShouldBe(0);
+        result.Settings.ShouldBeOfType<OptionWithArrayOfStringDefaultValueAndTypeConverterSettings>().And(settings =>
+        {
+            settings.Numbers.ShouldBe(new[] { 2, 3 });
+        });
+    }
+
     [Fact]
     public void Should_Throw_If_Required_Argument_Have_Default_Value()
     {