Add support for bar charts

Closes #103

src/Spectre.Console/Extensions/BarGraphExtensions.cs

@@ -0,0 +1,234 @@
+using System;
+using System.Collections.Generic;
+
+namespace Spectre.Console
+{
+    /// <summary>
+    /// Contains extension methods for <see cref="BarChart"/>.
+    /// </summary>
+    public static class BarGraphExtensions
+    {
+        /// <summary>
+        /// Adds an item to the bar chart.
+        /// </summary>
+        /// <param name="chart">The bar chart.</param>
+        /// <param name="label">The item label.</param>
+        /// <param name="value">The item value.</param>
+        /// <param name="color">The item color.</param>
+        /// <returns>The same instance so that multiple calls can be chained.</returns>
+        public static BarChart AddItem(this BarChart chart, string label, double value, Color? color = null)
+        {
+            if (chart is null)
+            {
+                throw new ArgumentNullException(nameof(chart));
+            }
+
+            chart.Data.Add(new BarChartItem(label, value, color));
+            return chart;
+        }
+
+        /// <summary>
+        /// Adds an item to the bar chart.
+        /// </summary>
+        /// <typeparam name="T">A type that implements <see cref="IBarChartItem"/>.</typeparam>
+        /// <param name="chart">The bar chart.</param>
+        /// <param name="item">The item.</param>
+        /// <returns>The same instance so that multiple calls can be chained.</returns>
+        public static BarChart AddItem<T>(this BarChart chart, T item)
+            where T : IBarChartItem
+        {
+            if (chart is null)
+            {
+                throw new ArgumentNullException(nameof(chart));
+            }
+
+            chart.Data.Add(new BarChartItem(
+                    item.Label,
+                    item.Value,
+                    item.Color));
+
+            return chart;
+        }
+
+        /// <summary>
+        /// Adds multiple items to the bar chart.
+        /// </summary>
+        /// <typeparam name="T">A type that implements <see cref="IBarChartItem"/>.</typeparam>
+        /// <param name="chart">The bar chart.</param>
+        /// <param name="items">The items.</param>
+        /// <returns>The same instance so that multiple calls can be chained.</returns>
+        public static BarChart AddItems<T>(this BarChart chart, IEnumerable<T> items)
+            where T : IBarChartItem
+        {
+            if (chart is null)
+            {
+                throw new ArgumentNullException(nameof(chart));
+            }
+
+            if (items is null)
+            {
+                throw new ArgumentNullException(nameof(items));
+            }
+
+            foreach (var item in items)
+            {
+                AddItem<T>(chart, item);
+            }
+
+            return chart;
+        }
+
+        /// <summary>
+        /// Adds multiple items to the bar chart.
+        /// </summary>
+        /// <typeparam name="T">A type that implements <see cref="IBarChartItem"/>.</typeparam>
+        /// <param name="chart">The bar chart.</param>
+        /// <param name="items">The items.</param>
+        /// <param name="converter">The converter that converts instances of <c>T</c> to <see cref="BarChartItem"/>.</param>
+        /// <returns>The same instance so that multiple calls can be chained.</returns>
+        public static BarChart AddItems<T>(this BarChart chart, IEnumerable<T> items, Func<T, BarChartItem> converter)
+        {
+            if (chart is null)
+            {
+                throw new ArgumentNullException(nameof(chart));
+            }
+
+            if (items is null)
+            {
+                throw new ArgumentNullException(nameof(items));
+            }
+
+            if (converter is null)
+            {
+                throw new ArgumentNullException(nameof(converter));
+            }
+
+            foreach (var item in items)
+            {
+                chart.Data.Add(converter(item));
+            }
+
+            return chart;
+        }
+
+        /// <summary>
+        /// Sets the width of the bar chart.
+        /// </summary>
+        /// <param name="chart">The bar chart.</param>
+        /// <param name="width">The bar chart width.</param>
+        /// <returns>The same instance so that multiple calls can be chained.</returns>
+        public static BarChart Width(this BarChart chart, int? width)
+        {
+            if (chart is null)
+            {
+                throw new ArgumentNullException(nameof(chart));
+            }
+
+            chart.Width = width;
+            return chart;
+        }
+
+        /// <summary>
+        /// Sets the label of the bar chart.
+        /// </summary>
+        /// <param name="chart">The bar chart.</param>
+        /// <param name="label">The bar chart label.</param>
+        /// <returns>The same instance so that multiple calls can be chained.</returns>
+        public static BarChart Label(this BarChart chart, string? label)
+        {
+            if (chart is null)
+            {
+                throw new ArgumentNullException(nameof(chart));
+            }
+
+            chart.Label = label;
+            return chart;
+        }
+
+        /// <summary>
+        /// Shows values next to each bar in the bar chart.
+        /// </summary>
+        /// <param name="chart">The bar chart.</param>
+        /// <returns>The same instance so that multiple calls can be chained.</returns>
+        public static BarChart ShowValues(this BarChart chart)
+        {
+            return ShowValues(chart, true);
+        }
+
+        /// <summary>
+        /// Hides values next to each bar in the bar chart.
+        /// </summary>
+        /// <param name="chart">The bar chart.</param>
+        /// <returns>The same instance so that multiple calls can be chained.</returns>
+        public static BarChart HideValues(this BarChart chart)
+        {
+            return ShowValues(chart, false);
+        }
+
+        /// <summary>
+        /// Sets whether or not values should be shown
+        /// next to each bar.
+        /// </summary>
+        /// <param name="chart">The bar chart.</param>
+        /// <param name="show">Whether or not values should be shown next to each bar.</param>
+        /// <returns>The same instance so that multiple calls can be chained.</returns>
+        public static BarChart ShowValues(this BarChart chart, bool show)
+        {
+            if (chart is null)
+            {
+                throw new ArgumentNullException(nameof(chart));
+            }
+
+            chart.ShowValues = show;
+            return chart;
+        }
+
+        /// <summary>
+        /// Aligns the label to the left.
+        /// </summary>
+        /// <param name="chart">The bar chart.</param>
+        /// <returns>The same instance so that multiple calls can be chained.</returns>
+        public static BarChart LeftAlignLabel(this BarChart chart)
+        {
+            if (chart is null)
+            {
+                throw new ArgumentNullException(nameof(chart));
+            }
+
+            chart.LabelAlignment = Justify.Left;
+            return chart;
+        }
+
+        /// <summary>
+        /// Centers the label.
+        /// </summary>
+        /// <param name="chart">The bar chart.</param>
+        /// <returns>The same instance so that multiple calls can be chained.</returns>
+        public static BarChart CenterLabel(this BarChart chart)
+        {
+            if (chart is null)
+            {
+                throw new ArgumentNullException(nameof(chart));
+            }
+
+            chart.LabelAlignment = Justify.Center;
+            return chart;
+        }
+
+        /// <summary>
+        /// Aligns the label to the right.
+        /// </summary>
+        /// <param name="chart">The bar chart.</param>
+        /// <returns>The same instance so that multiple calls can be chained.</returns>
+        public static BarChart RightAlignLabel(this BarChart chart)
+        {
+            if (chart is null)
+            {
+                throw new ArgumentNullException(nameof(chart));
+            }
+
+            chart.LabelAlignment = Justify.Right;
+            return chart;
+        }
+    }
+}

src/Spectre.Console/Extensions/GridExtensions.cs

@@ -97,5 +97,22 @@ namespace Spectre.Console
             grid.AddRow(columns.Select(column => new Markup(column)).ToArray());
             return grid;
         }
+
+        /// <summary>
+        /// Sets the grid width.
+        /// </summary>
+        /// <param name="grid">The grid.</param>
+        /// <param name="width">The width.</param>
+        /// <returns>The same instance so that multiple calls can be chained.</returns>
+        public static Grid Width(this Grid grid, int? width)
+        {
+            if (grid is null)
+            {
+                throw new ArgumentNullException(nameof(grid));
+            }
+
+            grid.Width = width;
+            return grid;
+        }
     }
 }

src/Spectre.Console/Extensions/TableExtensions.cs

@@ -150,7 +150,7 @@ namespace Spectre.Console
         /// <param name="table">The table.</param>
         /// <param name="width">The width.</param>
         /// <returns>The same instance so that multiple calls can be chained.</returns>
-        public static Table Width(this Table table, int width)
+        public static Table Width(this Table table, int? width)
         {
             if (table is null)
             {