Add FilterOperation

BitzArt · Feb 29, 2024 · d41ef05 · d41ef05
1 parent 97a6e7d
commit d41ef05
Show file tree

Hide file tree

Showing 3 changed files with 123 additions and 6 deletions.
diff --git a/src/BitzArt.LinqExtensions/Enums/FilterOperation.cs b/src/BitzArt.LinqExtensions/Enums/FilterOperation.cs
@@ -0,0 +1,11 @@
+namespace System.Linq;
+
+public enum FilterOperation : byte
+{
+    Equal = 0,
+    NotEqual = 1,
+    GreaterThan = 2,
+    GreaterThanOrEqual = 3,
+    LessThan = 4,
+    LessThanOrEqual = 5
+}
diff --git a/src/BitzArt.LinqExtensions/Extensions/AddFilterExtension.cs b/src/BitzArt.LinqExtensions/Extensions/AddFilterExtension.cs
@@ -5,15 +5,15 @@ namespace System.Linq;
 
 public static class AddFilterExtension
 {
-    public static IQueryable<TSource> AddFilter<TSource, TProperty>(this IQueryable<TSource> source, Expression<Func<TSource, TProperty?>> expression, TProperty? filter)
+    public static IQueryable<TSource> AddFilter<TSource, TProperty>(this IQueryable<TSource> source, Expression<Func<TSource, TProperty?>> expression, TProperty? filter, FilterOperation filterOperation = FilterOperation.Equal)
         where TProperty : class
     {
         if (filter is null) return source;
 
-        return BuildExpression(source, filter, expression);
+        return BuildExpression(source, filter, expression, filterOperation);
     }
 
-    public static IQueryable<TSource> AddFilter<TSource, TProperty>(this IQueryable<TSource> source, Expression<Func<TSource, TProperty?>> expression, TProperty? filter)
+    public static IQueryable<TSource> AddFilter<TSource, TProperty>(this IQueryable<TSource> source, Expression<Func<TSource, TProperty?>> expression, TProperty? filter, FilterOperation filterOperation = FilterOperation.Equal)
         where TProperty : struct
     {
         if (filter is null) return source;
@@ -22,15 +22,25 @@ public static IQueryable<TSource> AddFilter<TSource, TProperty>(this IQueryable<
         Expression<Func<TProperty?, TProperty>> getValueExpression = x => x!.Value;
         var valueExpression = expression.Compose(getValueExpression);
 
-        return BuildExpression(source, filterValue, valueExpression);
+        return BuildExpression(source, filterValue, valueExpression, filterOperation);
     }
 
-    private static IQueryable<TSource> BuildExpression<TSource, TProperty>(IQueryable<TSource> source, TProperty filter, Expression<Func<TSource, TProperty>> expression)
+    private static IQueryable<TSource> BuildExpression<TSource, TProperty>(IQueryable<TSource> source, TProperty filter, Expression<Func<TSource, TProperty>> expression, FilterOperation filterOperation)
     {
         var argument = Expression.Parameter(typeof(TSource));
         var left = Expression.Invoke(expression, argument);
         var right = Expression.Constant(filter);
-        var eq = Expression.Equal(left, right);
+
+        var eq = filterOperation switch
+        {
+            FilterOperation.Equal => Expression.Equal(left, right),
+            FilterOperation.NotEqual => Expression.NotEqual(left, right),
+            FilterOperation.GreaterThan => Expression.GreaterThan(left, right),
+            FilterOperation.GreaterThanOrEqual => Expression.GreaterThanOrEqual(left, right),
+            FilterOperation.LessThan => Expression.LessThan(left, right),
+            FilterOperation.LessThanOrEqual => Expression.LessThanOrEqual(left, right),
+            _ => throw new NotImplementedException($"Unsupported Filter Operation: '{filterOperation}'")
+        };
 
         var lambda = Expression
             .Lambda<Func<TSource, bool>>(eq, new[] { argument });

diff --git a/tests/BitzArt.LinqExtensions.Tests/AddFilterTests.cs b/tests/BitzArt.LinqExtensions.Tests/AddFilterTests.cs
@@ -69,5 +69,101 @@ public void StructFilter_FilterNull_DoesNotFilter()
 
             Assert.Equal(models, filtered);
         }
+
+        [Theory]
+        [InlineData(1)]
+        [InlineData(2)]
+        [InlineData(3)]
+        [InlineData(4)]
+        [InlineData(5)]
+        [InlineData(6)]
+        [InlineData(7)]
+        [InlineData(8)]
+        [InlineData(9)]
+        [InlineData(10)]
+        public void NotEqual_Filter_Filters(int notEqualTo)
+        {
+            var range = Enumerable.Range(1, 10);
+            var models = range.Select(x => new TestModelStruct { Id = x }).ToList();
+            var queryable = models.AsQueryable();
+
+            int? filter = notEqualTo;
+
+            var filtered = queryable.AddFilter(x => x.Id, filter, FilterOperation.NotEqual).ToList();
+
+            Assert.Equal(9, filtered.Count);
+
+            if (notEqualTo != 1) Assert.True(filtered.First().Id == 1);
+            else Assert.True(filtered.First().Id == 2);
+
+            if (notEqualTo != 10) Assert.True(filtered.Last().Id == 10);
+            else Assert.True(filtered.Last().Id == 9);
+
+            Assert.DoesNotContain(filtered, x => x.Id == filter);
+        }
+
+        [Fact]
+        public void GreaterThan_Filter_Filters()
+        {
+            var range = Enumerable.Range(1, 10);
+            var models = range.Select(x => new TestModelStruct { Id = x }).ToList();
+            var queryable = models.AsQueryable();
+
+            int? filter = 5;
+
+            var filtered = queryable.AddFilter(x => x.Id, filter, FilterOperation.GreaterThan).ToList();
+
+            Assert.Equal(5, filtered.Count);
+            Assert.True(filtered.First().Id == 6);
+            Assert.True(filtered.Last().Id == 10);
+        }
+
+        [Fact]
+        public void GreaterThanOrEqual_Filter_Filters()
+        {
+            var range = Enumerable.Range(1, 10);
+            var models = range.Select(x => new TestModelStruct { Id = x }).ToList();
+            var queryable = models.AsQueryable();
+
+            int? filter = 5;
+
+            var filtered = queryable.AddFilter(x => x.Id, filter, FilterOperation.GreaterThanOrEqual).ToList();
+
+            Assert.Equal(6, filtered.Count);
+            Assert.True(filtered.First().Id == 5);
+            Assert.True(filtered.Last().Id == 10);
+        }
+
+        [Fact]
+        public void LessThan_Filter_Filters()
+        {
+            var range = Enumerable.Range(1, 10);
+            var models = range.Select(x => new TestModelStruct { Id = x }).ToList();
+            var queryable = models.AsQueryable();
+
+            int? filter = 5;
+
+            var filtered = queryable.AddFilter(x => x.Id, filter, FilterOperation.LessThan).ToList();
+
+            Assert.Equal(4, filtered.Count);
+            Assert.True(filtered.First().Id == 1);
+            Assert.True(filtered.Last().Id == 4);
+        }
+
+        [Fact]
+        public void LessThanOrEqual_Filter_Filters()
+        {
+            var range = Enumerable.Range(1, 10);
+            var models = range.Select(x => new TestModelStruct { Id = x }).ToList();
+            var queryable = models.AsQueryable();
+
+            int? filter = 5;
+
+            var filtered = queryable.AddFilter(x => x.Id, filter, FilterOperation.LessThanOrEqual).ToList();
+
+            Assert.Equal(5, filtered.Count);
+            Assert.True(filtered.First().Id == 1);
+            Assert.True(filtered.Last().Id == 5);
+        }
     }
 }