Subqueryable

Author: Revolucent

CoreDataQueryInterface/Protocols.swift

@@ -170,3 +170,12 @@ extension KeyPathExpressionConvertible {
     }
 }
 
+public protocol Subqueryable: KeyPathExpressionConvertible {
+    func cdqiSubquery(_ query: (Self) -> NSPredicate) -> ExpressionConvertible
+}
+
+extension Subqueryable where Self: EntityAttribute {
+    public func cdqiSubquery(_ query: (Self) -> NSPredicate) -> ExpressionConvertible {
+        return subquery(self, query)
+    }
+}

CoreDataQueryInterfaceTests/DepartmentAttribute.swift

@@ -24,7 +24,7 @@ SOFTWARE.
 
 import CoreDataQueryInterface
 
-class DepartmentAttribute: EntityAttribute {
+final class DepartmentAttribute: EntityAttribute, Subqueryable {
     private(set) lazy var name: StringAttribute = { StringAttribute(key: "name", parent: self) }()
     private(set) lazy var employees: EmployeeAttribute = { EmployeeAttribute(key: "employees", parent: self) }()
 }

CoreDataQueryInterfaceTests/EmployeeAttribute.swift

@@ -24,7 +24,7 @@ SOFTWARE.
 
 import CoreDataQueryInterface
 
-class EmployeeAttribute: EntityAttribute {
+final class EmployeeAttribute: EntityAttribute, Subqueryable {
     private(set) lazy var firstName: StringAttribute = { StringAttribute(key: "firstName", parent: self) }()
     private(set) lazy var lastName: StringAttribute = { StringAttribute(key: "lastName", parent: self) }()
     private(set) lazy var nickName: StringAttribute = { StringAttribute(key: "nickName", parent: self) }()

CoreDataQueryInterfaceTests/FilterTests.swift

@@ -88,8 +88,8 @@ class FilterTests : BaseTestCase {
 
     func testNumberOfDepartmentsWithEmployeesWhoseLastNamesStartWithSUsingSubquery() {
         let departmentCount = try! managedObjectContext.from(Department.self).filter{ department in
-            subquery(department.employees) { (employee: EmployeeAttribute) in
-                some(employee.lastName.cdqiBeginsWith("S", options: .caseInsensitive))
+            department.employees.cdqiSubquery {
+                some($0.lastName.cdqiBeginsWith("S", options: .caseInsensitive))
             }.cdqiCount() > 0
         }.count()
         XCTAssertEqual(departmentCount, 2)

CoreDataQueryInterfaceTests/TestEntityAttribute.swift

@@ -24,7 +24,7 @@ SOFTWARE.
 
 import CoreDataQueryInterface
 
-class TestEntityAttribute: EntityAttribute {
+final class TestEntityAttribute: EntityAttribute, Subqueryable {
     private(set) lazy var binary: DataAttribute = { DataAttribute(key: "binary", parent: self) }()
     private(set) lazy var boolean: BoolAttribute = { BoolAttribute(key: "boolean", parent: self) }()
     private(set) lazy var date: DateAttribute = { DateAttribute(key: "date", parent: self) }()