Fix wrong type returned by NotNullOrEmpty() and HasNoNulls()

lecaillon · Feb 16, 2022 · ed3f78a · ed3f78a
1 parent 65ce462
commit ed3f78a
Show file tree

Hide file tree

Showing 3 changed files with 15 additions and 65 deletions.
diff --git a/src/Preconditions/Check.cs b/src/Preconditions/Check.cs
@@ -1,10 +1,9 @@
 namespace Preconditions
 {
     using System;
-    using System.Collections.Generic;
+    using System.Collections;
     using System.Diagnostics.CodeAnalysis;
     using System.IO;
-    using System.Linq;
     using System.Runtime.CompilerServices;
 
     /// <summary>
@@ -74,33 +73,16 @@ public static string NotNullOrEmpty([NotNull] string? text, [CallerArgumentExpre
             return text;
         }
 
-        /// <summary>
-        ///     Ensures that a collection contains at least one element.
-        /// </summary>
-        /// <exception cref="ArgumentNullException"/>
-        /// <exception cref="ArgumentException"/>
-        public static ICollection<T> NotNullOrEmpty<T>([NotNull] ICollection<T>? collection, [CallerArgumentExpression("collection")] string? paramName = null)
-        {
-            NotNull(collection, paramName);
-
-            if (collection.Count == 0)
-            {
-                ThrowArgumentException(CollectionArgumentIsEmpty, paramName);
-            }
-
-            return collection;
-        }
-
         /// <summary>
         ///     Ensures that an enumerable contains at least one element.
         /// </summary>
         /// <exception cref="ArgumentNullException"/>
         /// <exception cref="ArgumentException"/>
-        public static IEnumerable<T> NotNullOrEmpty<T>([NotNull] IEnumerable<T>? enumerable, [CallerArgumentExpression("enumerable")] string? paramName = null)
+        public static T NotNullOrEmpty<T>([NotNull] T? enumerable, [CallerArgumentExpression("enumerable")] string? paramName = null) where T : IEnumerable
         {
             NotNull(enumerable, paramName);
 
-            if (!enumerable.Any())
+            if (!enumerable.GetEnumerator().MoveNext())
             {
                 ThrowArgumentException(CollectionArgumentIsEmpty, paramName);
             }
@@ -113,13 +95,17 @@ public static IEnumerable<T> NotNullOrEmpty<T>([NotNull] IEnumerable<T>? enumera
         /// </summary>
         /// <exception cref="ArgumentNullException"/>
         /// <exception cref="ArgumentException"/>
-        public static IEnumerable<T> HasNoNulls<T>([NotNull] IEnumerable<T>? enumerable, [CallerArgumentExpression("enumerable")] string? paramName = null)
+        public static T HasNoNulls<T>([NotNull] T? enumerable, [CallerArgumentExpression("enumerable")] string? paramName = null) where T : IEnumerable
         {
             NotNull(enumerable, paramName);
 
-            if (enumerable.Any(e => e is null))
+
+            foreach (var item in enumerable)
             {
-                ThrowArgumentException(CollectionArgumentHasNullElement, paramName);
+                if (item is null)
+                {
+                    ThrowArgumentException(CollectionArgumentHasNullElement, paramName);
+                }
             }
 
             return enumerable;

diff --git a/src/Preconditions/Preconditions.csproj b/src/Preconditions/Preconditions.csproj
@@ -7,7 +7,7 @@
 		<TreatWarningsAsErrors>true</TreatWarningsAsErrors>
 		<PackageId>Preconditions.NET</PackageId>
 		<Authors>Philippe Lécaillon</Authors>
-		<Version>2.0.1</Version>
+		<Version>2.0.2</Version>
 		<Copyright>Copyright © P.Lécaillon 2022</Copyright>
 		<Description>Preconditions provide convenience static methods that help to check that a method or a constructor is invoked with proper parameter or not. In other words it checks the pre-conditions.</Description>
 		<PackageIcon>logo128.png</PackageIcon>
@@ -16,7 +16,7 @@
 		<RepositoryType>git</RepositoryType>
 		<PackageTags>preconditions;guard;check;argument-checks</PackageTags>
 		<PackageReleaseNotes>## Bug fix
-- Add missing NotNullAttribute</PackageReleaseNotes>
+- NotNullOrEmpty(IEnumerable) and HasNoNulls(IEnumerable) return the same type as the one passed in parameter</PackageReleaseNotes>
 	</PropertyGroup>
 
 	<ItemGroup>

diff --git a/tests/Preconditions.Tests/CheckTest.cs b/tests/Preconditions.Tests/CheckTest.cs
@@ -100,43 +100,7 @@ public void Text_Is_Considered_Not_Null_After_Calling_NotNullOrEmpty()
 
         #endregion
 
-        #region Check.NotNullOrEmpty : ICollection
-
-        [Fact]
-        public void NotNullOrEmpty_When_Collection_Is_Null_Throws_ArgumentNullException()
-        {
-            ICollection<int>? collection = null;
-
-            Assert.Throws<ArgumentNullException>(nameof(collection), () => Check.NotNullOrEmpty(collection));
-        }
-
-        [Fact]
-        public void NotNullOrEmpty_When_Collection_Has_No_Element_Throws_ArgumentException()
-        {
-            ICollection<int> collection = new List<int>();
-
-            Assert.Throws<ArgumentException>(nameof(collection), () => Check.NotNullOrEmpty(collection));
-        }
-
-        [Fact]
-        public void NotNullOrEmpty_When_Collection_Is_Not_Empty_Returns_Collection()
-        {
-            ICollection<int> collection = new List<int> { 1, 2, 3 };
-
-            Assert.Same(collection, Check.NotNullOrEmpty(collection));
-        }
-
-        [Fact]
-        public void Collection_Is_Considered_Not_Null_After_Calling_NotNullOrEmpty()
-        {
-            ICollection<int>? collection = new List<int> { 1 };
-            Check.NotNullOrEmpty(collection);
-            collection.ToString();
-        }
-
-        #endregion
-
-        #region Check.NotNullOrEmpty : IEnumerable
+        #region Check.NotNullOrEmpty
 
         [Fact]
         public void NotNullOrEmpty_When_Enumerable_Is_Null_Throws_ArgumentNullException()
@@ -149,15 +113,15 @@ public void NotNullOrEmpty_When_Enumerable_Is_Null_Throws_ArgumentNullException(
         [Fact]
         public void NotNullOrEmpty_When_Enumerable_Has_No_Element_Throws_ArgumentException()
         {
-            IEnumerable<int> enumerable = new List<int>();
+            var enumerable = new List<int>();
 
             Assert.Throws<ArgumentException>(nameof(enumerable), () => Check.NotNullOrEmpty(enumerable));
         }
 
         [Fact]
         public void NotNullOrEmpty_When_Enumerable_Is_Not_Empty_Returns_Enumerable()
         {
-            IEnumerable<int> enumerable = new List<int> { 1, 2, 3 };
+            var enumerable = new List<int> { 1, 2, 3 };
 
             Assert.Same(enumerable, Check.NotNullOrEmpty(enumerable));
         }