Fixed Count() and Exists() in InMemoryAdapter

ThatRendle · ThatRendle · commit d1dcdbc6d0e8 · 2011-11-28T20:03:47.000Z
diff --git a/CommonAssemblyInfo.cs b/CommonAssemblyInfo.cs
@@ -19,6 +19,6 @@
 // COM, set the ComVisible attribute to true on that type.
 [assembly: ComVisible(false)]
 
-[assembly: AssemblyVersion("0.11.4.1")]
-[assembly: AssemblyFileVersion("0.11.4.1")]
+[assembly: AssemblyVersion("0.12.0.1")]
+[assembly: AssemblyFileVersion("0.12.0.1")]
 
diff --git a/Simple.Data.InMemoryTest/InMemoryTests.cs b/Simple.Data.InMemoryTest/InMemoryTests.cs
@@ -350,6 +350,38 @@ public void AutoIncrementShouldReturnNextIdInSequenceWhenOneRowExsists()
             Assert.AreEqual(2, newId);
         }
 
+        [Test]
+        public void SelectCountShouldReturnCount()
+        {
+            Database.UseMockAdapter(new InMemoryAdapter());
+            var db = Database.Open();
+            db.Test.Insert(Id: 1, Name: "Alice");
+            db.Test.Insert(Id: 2, Name: "Bob");
+
+            var count = db.Test.All().Count();
+            Assert.AreEqual(2, count);
+        }
+
+        [Test]
+        public void SelectExistsShouldReturnTrueForAnyRows()
+        {
+            Database.UseMockAdapter(new InMemoryAdapter());
+            var db = Database.Open();
+            db.Test.Insert(Id: 1, Name: "Alice");
+            db.Test.Insert(Id: 2, Name: "Bob");
+
+            Assert.IsTrue(db.Test.All().Exists());
+        }
+
+        [Test]
+        public void SelectExistsShouldReturnFalseForNoRows()
+        {
+            Database.UseMockAdapter(new InMemoryAdapter());
+            var db = Database.Open();
+
+            Assert.IsFalse(db.Test.All().Exists());
+        }
+
         private static int ThreadTestHelper(int userId)
         {
             var mockAdapter = new InMemoryAdapter();
diff --git a/Simple.Data/QueryPolyfills/SelectClauseHandler.cs b/Simple.Data/QueryPolyfills/SelectClauseHandler.cs
@@ -15,12 +15,15 @@ class SelectClauseHandler
         public SelectClauseHandler(SelectClause clause)
         {
             _references = clause.Columns.ToList();
-            _resolvers = _references.Select(ValueResolver.Create).ToList();
-            if (_resolvers.OfType<AggregateValueResolver>().Any())
+            if (!(_references.Count == 1 && _references[0] is SpecialReference))
             {
-                _groupingHandler =
-                    new GroupingHandler(
-                        _references.Where(ReferenceIsNotAggregateFunction).Select(r => r.GetAliasOrName()).ToArray());
+                _resolvers = _references.Select(ValueResolver.Create).ToList();
+                if (_resolvers.OfType<AggregateValueResolver>().Any())
+                {
+                    _groupingHandler =
+                        new GroupingHandler(
+                            _references.Where(ReferenceIsNotAggregateFunction).Select(r => r.GetAliasOrName()).ToArray());
+                }
             }
         }
 
@@ -31,10 +34,24 @@ public IEnumerable<IDictionary<string,object>> Run(IEnumerable<IDictionary<strin
                 var groupedSource = _groupingHandler.Group(source);
                 return groupedSource.Select(Run);
             }
-            else
+
+            if (_references.Count == 1)
             {
-                return source.Select(Run);
+                if (_references[0] is CountSpecialReference)
+                {
+                    return new[] {new Dictionary<string, object> {{"", source.Count()}}};
+                }
+
+                if (_references[0] is ExistsSpecialReference)
+                {
+                    if (source.Any())
+                    {
+                        return new[] {new Dictionary<string, object> {{"", 1}}};
+                    }
+                    return Enumerable.Empty<IDictionary<string, object>>();
+                }
             }
+            return source.Select(Run);
         }
 
         public IDictionary<string, object> Run(IGrouping<IDictionary<string, object>, IDictionary<string, object>> grouping)
diff --git a/Simple.Data/QueryPolyfills/ValueResolver.cs b/Simple.Data/QueryPolyfills/ValueResolver.cs
@@ -17,6 +17,7 @@ public static ValueResolver Create(SimpleReference reference)
                 if (FunctionHandlers.Exists(functionReference.Name)) return new AggregateValueResolver(functionReference);
                 return new FunctionValueResolver(functionReference);
             }
+
             throw new InvalidOperationException("Unresolvable Reference type.");
         }
 

Original file line number	Diff line number	Diff line change
`@@ -17,6 +17,7 @@ public static ValueResolver Create(SimpleReference reference)`
`17`	`17`	`if (FunctionHandlers.Exists(functionReference.Name)) return new AggregateValueResolver(functionReference);`
`18`	`18`	`return new FunctionValueResolver(functionReference);`
`19`	`19`	`}`
	`20`	`+`
`20`	`21`	`throw new InvalidOperationException("Unresolvable Reference type.");`
`21`	`22`	`}`
`22`	`23`