Strongly type SetRange, add GetRange

Author: mhutch

src/System.CommandLine.Subsystems/ValueConditionAnnotationExtensions.cs

@@ -13,41 +13,52 @@ namespace System.CommandLine;
 public static class ValueConditionAnnotationExtensions
 {
     /// <summary>
-    /// Set the upper and/or lower bound values of the range.
+    /// Set upper and/or lower bounds on the range of values that the symbol value may have.
     /// </summary>
-    /// <typeparam name="T">The type of the bounds.</typeparam>
+    /// <typeparam name="TValueSymbol">The type of the symbol whose value is bounded by the range.</typeparam>
+    /// <typeparam name="TValue">The type of the value that is bounded by the range.</typeparam>
     /// <param name="symbol">The option or argument the range applies to.</param>
     /// <param name="lowerBound">The lower bound of the range.</param>
     /// <param name="upperBound">The upper bound of the range.</param>
     // TODO: Add RangeBounds
     // TODO: You should not have to set both...why not nullable?
-    public static void SetRange<T>(this CliValueSymbol symbol, T lowerBound, T upperBound)
-        where T : IComparable<T>
+    public static void SetRange<TValueSymbol, TValue>(this TValueSymbol symbol, TValue lowerBound, TValue upperBound)
+        where TValueSymbol : CliValueSymbol, ICliValueSymbol<TValue>
+        where TValue : IComparable<TValue>
     {
-        var range = new Range<T>(lowerBound, upperBound);
+        var range = new Range<TValue>(lowerBound, upperBound);
 
         symbol.SetValueCondition(range);
     }
 
     /// <summary>
-    /// Set the upper and/or lower bound via ValueSource. Implicit conversions means this 
-    /// generally just works with any <see cref="ValueSource">.
+    /// Set upper and/or lower <see cref="ValueSource"> bounds on the range of values that the symbol value may have.
+    /// Implicit conversions means this generally just works with any <see cref="ValueSource">.
     /// </summary>
-    /// <typeparam name="T">The type of the bounds.</typeparam>
+    /// <typeparam name="TValueSymbol">The type of the symbol whose value is bounded by the range.</typeparam>
+    /// <typeparam name="TValue">The type of the value that is bounded by the range.</typeparam>
     /// <param name="symbol">The option or argument the range applies to.</param>
     /// <param name="lowerBound">The <see cref="ValueSource"> that is the lower bound of the range.</param>
     /// <param name="upperBound">The <see cref="ValueSource"> that is the upper bound of the range.</param>
     // TODO: Add RangeBounds
     // TODO: You should not have to set both...why not nullable?
-    public static void SetRange<T>(this CliValueSymbol symbol, ValueSource<T> lowerBound, ValueSource<T> upperBound)
-        where T : IComparable<T>
+    public static void SetRange<TValueSymbol, TValue>(this TValueSymbol symbol, ValueSource<TValue> lowerBound, ValueSource<TValue> upperBound)
+        where TValueSymbol : CliValueSymbol, ICliValueSymbol<TValue>
+        where TValue : IComparable<TValue>
         // TODO: You should not have to set both...why not nullable?
     {
-        var range = new Range<T>(lowerBound, upperBound);
+        var range = new Range<TValue>(lowerBound, upperBound);
 
         symbol.SetValueCondition(range);
     }
 
+    /// <summary>
+    /// Get the upper and/or lower bound of the symbol's value.
+    /// </summary>
+    /// <param name="symbol">The option or argument the range applies to.</param>
+    public static ValueConditions.Range? GetRange(this CliValueSymbol symbol)
+        => symbol.GetValueCondition<ValueConditions.Range>();
+
     /// <summary>
     /// Indicates that there is an inclusive group of options and arguments for the command. All
     /// members of an inclusive must be present, or none can be present.

src/System.CommandLine/CliArgument{T}.cs

@@ -4,12 +4,12 @@
 using System.Collections.Generic;
 using System.CommandLine.Parsing;
 using System.Diagnostics.CodeAnalysis;
-using System.IO;
 
 namespace System.CommandLine
 {
+
     /// <inheritdoc cref="CliArgument" />
-    public class CliArgument<T> : CliArgument
+    public class CliArgument<T> : CliArgument, ICliValueSymbol<T>
     {
         // TODO: custom parser
         /*

src/System.CommandLine/CliOption{T}.cs

@@ -7,7 +7,7 @@ namespace System.CommandLine
 {
     /// <inheritdoc cref="CliOption" />
     /// <typeparam name="T">The <see cref="System.Type"/> that the option's arguments are expected to be parsed as.</typeparam>
-    public class CliOption<T> : CliOption
+    public class CliOption<T> : CliOption, ICliValueSymbol<T>
     {
 // TODO: do not expose private fields
         internal readonly CliArgument<T> _argument;

src/System.CommandLine/ICliValueSymbol.cs

@@ -0,0 +1,14 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+namespace System.CommandLine;
+
+/// <summary>
+/// This is applied to <see cref="CliArgument{T}"/> and <see cref="CliArgument{T}"/>, and allows
+/// allows methods with a <see cref="CliValueSymbol"/> argument to apply constraints based on the
+/// value type.
+/// </summary>
+/// <typeparam name="TValue">The value type</typeparam>
+public interface ICliValueSymbol<TValue>
+{
+}

src/System.CommandLine/System.CommandLine.csproj

@@ -27,6 +27,7 @@
     <Compile Include="ArgumentArity.cs" />
     <Compile Include="Binding\ArgumentConversionResult.cs" />
     <Compile Include="CliValueSymbol.cs" />
+    <Compile Include="ICliValueSymbol.cs" />
     <Compile Include="Parsing\CliCommandResult.cs" />
     <Compile Include="Parsing\CliSymbolResult.cs" />
     <Compile Include="Parsing\SymbolLookupByName.cs" />