mono/mcs/class/System.Core/Test/System.Linq.Expressions/ExpressionTest_Invoke.cs

//
// ExpressionTest_Invoke.cs
//
// Author:
//   Jb Evain ([email protected])
//
// (C) 2008 Novell, Inc. (http://www.novell.com)
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

using System;
using System.Reflection;
using System.Linq;
using System.Linq.Expressions;

using NUnit.Framework;

namespace MonoTests.System.Linq.Expressions {

	[TestFixture]
	[Category("SRE")]
	public class ExpressionTest_Invoke {

		static Expression CreateInvokable<T> ()
		{
			return Expression.Parameter (typeof (T), "invokable");
		}

		[Test]
		[ExpectedException (typeof (ArgumentNullException))]
		public void NullExpression ()
		{
			Expression.Invoke (null, new Expression [0]);
		}

		[Test]
		[ExpectedException (typeof (ArgumentNullException))]
		public void NullArgument ()
		{
			Expression.Invoke (CreateInvokable<Action<int>> (), new [] { null as Expression });
		}

		[Test]
		[ExpectedException (typeof (ArgumentException))]
		public void NonInvokableExpressionType ()
		{
			Expression.Invoke (CreateInvokable<int> (), null);
		}

		[Test]
		[ExpectedException (typeof (InvalidOperationException))]
		public void ArgumentCountDoesntMatchParametersLength ()
		{
			Expression.Invoke (CreateInvokable<Action<int>> (), 1.ToConstant (), 2.ToConstant ());
		}

		[Test]
		[ExpectedException (typeof (ArgumentException))]
		public void ArgumentNotAssignableToParameterType ()
		{
			Expression.Invoke (CreateInvokable<Action<int>> (), "".ToConstant ());
		}

		[Test]
		public void EmptyArguments ()
		{
			var invoke = Expression.Invoke (CreateInvokable<Action> (), null);
			Assert.AreEqual (typeof (void), invoke.Type);
			Assert.IsNotNull (invoke.Arguments);
			Assert.AreEqual (0, invoke.Arguments.Count);
			Assert.AreEqual ("Invoke(invokable)", invoke.ToString ());
		}

		[Test]
		[Category ("NotDotNet")] // https://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=352402
		public void InvokeFunc ()
		{
			var invoke = Expression.Invoke (CreateInvokable<Func<string, string, int>> (), "foo".ToConstant (), "bar".ToConstant ());
			Assert.AreEqual (typeof (int), invoke.Type);
			Assert.AreEqual (2, invoke.Arguments.Count);
			Assert.AreEqual ("Invoke(invokable, \"foo\", \"bar\")", invoke.ToString ());
		}

		[Test]
		[Category ("NotDotNet")] // https://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=352402
		public void InvokeLambda ()
		{
			var p = Expression.Parameter (typeof (int), "i");
			var lambda = Expression.Lambda<Func<int, int>> (p, p);

			var invoke = Expression.Invoke (lambda, 1.ToConstant ());
			Assert.AreEqual (typeof (int), invoke.Type);
			Assert.AreEqual (1, invoke.Arguments.Count);
			Assert.AreEqual ("Invoke(i => i, 1)", invoke.ToString ());
		}

		delegate string StringAction (string s);

		static string Identity (string s)
		{
			return s;
		}

		[Test]
		public void TestCompileInvokePrivateDelegate ()
		{
			var action = Expression.Parameter (typeof (StringAction), "action");
			var str = Expression.Parameter (typeof (string), "str");
			var invoker = Expression.Lambda<Func<StringAction, string, string>> (
				Expression.Invoke (action, str), action, str).Compile ();

			Assert.AreEqual ("foo", invoker (Identity, "foo"));
		}

		[Test]
		public void InvokeWithExpressionLambdaAsArguments ()
		{
			var p = Expression.Parameter (typeof (string), "s");

			Func<string, Expression<Func<string, string>>, string> caller = (s, f) => f.Compile ().Invoke (s);

			var invoke = Expression.Lambda<Func<string>> (
				Expression.Invoke (
					Expression.Constant (caller),
					Expression.Constant ("KABOOM!"),
					Expression.Lambda<Func<string, string>> (
						Expression.Call (p, typeof (string).GetMethod ("ToLowerInvariant")), p)));

			Assert.AreEqual (ExpressionType.Quote,
				(invoke.Body as InvocationExpression).Arguments [1].NodeType);

			Assert.AreEqual ("kaboom!", invoke.Compile ().DynamicInvoke ());
		}
	}
}