mcs/class/dlr/Runtime/Microsoft.Scripting.Core/Utils/ContractUtils.cs

   1 /* ****************************************************************************
   2  *
   3  * Copyright (c) Microsoft Corporation.
   4  *
   5  * This source code is subject to terms and conditions of the Apache License, Version 2.0. A
   6  * copy of the license can be found in the License.html file at the root of this distribution. If
   7  * you cannot locate the  Apache License, Version 2.0, please send an email to
   8  * dlr@microsoft.com. By using this source code in any fashion, you are agreeing to be bound
   9  * by the terms of the Apache License, Version 2.0.
  10  *
  11  * You must not remove this notice, or any other, from this software.
  12  *
  13  *
  14  * ***************************************************************************/
  15
  16 #if !FEATURE_CORE_DLR
  17 using Microsoft.Scripting.Ast;
  18 #else
  19 using System.Linq.Expressions;
  20 #endif
  21 #if SILVERLIGHT
  22 using System.Core;
  23 #endif
  24
  25 using System.Collections.Generic;
  26 using System.Diagnostics;
  27
  28 namespace System.Dynamic.Utils {
  29
  30     // Will be replaced with CLRv4 managed contracts
  31     internal static class ContractUtils {
  32
  33         internal static Exception Unreachable {
  34             get {
  35                 Debug.Assert(false, "Unreachable");
  36                 return new InvalidOperationException("Code supposed to be unreachable");
  37             }
  38         }
  39
  40         internal static void Requires(bool precondition) {
  41             if (!precondition) {
  42                 throw new ArgumentException(Strings.MethodPreconditionViolated);
  43             }
  44         }
  45
  46         internal static void Requires(bool precondition, string paramName) {
  47             Debug.Assert(!string.IsNullOrEmpty(paramName));
  48
  49             if (!precondition) {
  50                 throw new ArgumentException(Strings.InvalidArgumentValue, paramName);
  51             }
  52         }
  53
  54         internal static void RequiresNotNull(object value, string paramName) {
  55             Debug.Assert(!string.IsNullOrEmpty(paramName));
  56
  57             if (value == null) {
  58                 throw new ArgumentNullException(paramName);
  59             }
  60         }
  61
  62         internal static void RequiresNotEmpty<T>(ICollection<T> collection, string paramName) {
  63             RequiresNotNull(collection, paramName);
  64             if (collection.Count == 0) {
  65                 throw new ArgumentException(Strings.NonEmptyCollectionRequired, paramName);
  66             }
  67         }
  68
  69         /// <summary>
  70         /// Requires the range [offset, offset + count] to be a subset of [0, array.Count].
  71         /// </summary>
  72         /// <exception cref="ArgumentNullException">Array is <c>null</c>.</exception>
  73         /// <exception cref="ArgumentOutOfRangeException">Offset or count are out of range.</exception>
  74         internal static void RequiresArrayRange<T>(IList<T> array, int offset, int count, string offsetName, string countName) {
  75             Debug.Assert(!string.IsNullOrEmpty(offsetName));
  76             Debug.Assert(!string.IsNullOrEmpty(countName));
  77             Debug.Assert(array != null);
  78
  79             if (count < 0) throw new ArgumentOutOfRangeException(countName);
  80             if (offset < 0 || array.Count - offset < count) throw new ArgumentOutOfRangeException(offsetName);
  81         }
  82
  83         /// <summary>
  84         /// Requires the array and all its items to be non-null.
  85         /// </summary>
  86         internal static void RequiresNotNullItems<T>(IList<T> array, string arrayName) {
  87             Debug.Assert(arrayName != null);
  88             RequiresNotNull(array, arrayName);
  89
  90             for (int i = 0; i < array.Count; i++) {
  91                 if (array[i] == null) {
  92                     throw new ArgumentNullException(string.Format(System.Globalization.CultureInfo.CurrentCulture, "{0}[{1}]", arrayName, i));
  93                 }
  94             }
  95         }
  96     }
  97 }