Changes to remove warnings when compiling using Swift 5

Package.swift

@@ -12,5 +12,6 @@ let package = Package(
     targets: [
         .target(name: "Meow", dependencies: ["MongoKitten"]),
         .testTarget(name: "MeowTests", dependencies: ["Meow"]),
-    ]
+    ],
+    swiftLanguageVersions: [.v4_2, .version("5")]
 )

Sources/Meow/Compatibility.swift

@@ -0,0 +1,7 @@
+#if !swift(>=5.0)
+internal extension Array {
+    func firstIndex(where predicate: (Element) throws -> Bool) rethrows -> Int? {
+        return try self.index(where: predicate)
+    }
+}
+#endif

Sources/Meow/Migrations.swift

@@ -60,7 +60,7 @@ public class Migrator<M: Model> {
 
 public extension Migrator where M: QueryableModel {
 
-    public func ensureValue<V: Encodable>(for keyPath: KeyPath<M, V>, default value: V) {
+    func ensureValue<V: Encodable>(for keyPath: KeyPath<M, V>, default value: V) {
         add { collection in
             let path = try M.makeQueryPath(for: keyPath)
 
@@ -81,7 +81,7 @@ public extension Migrator where M: QueryableModel {
     /// This provides maximum flexibility.
     ///
     /// - parameter transform: A closure that will be executed on every model document in the database. The returned document from this closure replaces the existing document in the database.
-    public func map(_ transform: @escaping (Document) throws -> (Document)) {
+    func map(_ transform: @escaping (Document) throws -> (Document)) {
         add { collection in
             return collection.find().sequentialForEach { original in
                 let replacement = try transform(original)

Sources/Meow/Model.swift

@@ -29,7 +29,7 @@ public protocol Model: _Model {
 
 // MARK: - Default implementations
 public extension Model {
-    public func save(to context: Context) -> EventLoopFuture<Void> {
+    func save(to context: Context) -> EventLoopFuture<Void> {
         return context.save(self)
     }
 
@@ -49,12 +49,12 @@ public extension Model {
 public extension Model where Self: Hashable {
 
     /// Provides a default implementation of Hashable for Models, that uses only the _id for Hashable conformance
-    public var hashValue: Int {
-        return _id.hashValue
+    func hash(into hasher: inout Hasher) {
+        hasher.combine(_id)
     }
 
     /// Compares the given models using the _id
-    public static func == (lhs: Self, rhs: Self) -> Bool {
+    static func == (lhs: Self, rhs: Self) -> Bool {
         return lhs._id == rhs._id
     }
 

Sources/Meow/Reference.swift

@@ -14,8 +14,8 @@ public struct Reference<M: Model>: Hashable, Resolvable {
     }
 
     /// Makes a reference hashable
-    public var hashValue: Int {
-        return reference.hashValue
+    public func hash(into hasher: inout Hasher) {
+        hasher.combine(reference)
     }
 
     /// Creates a reference to an entity
@@ -75,21 +75,21 @@ public protocol Resolvable {
 }
 
 public extension Resolvable where Result: QueryableModel {
-    public func resolve(in context: Context, where query: ModelQuery<Result>) -> EventLoopFuture<Result> {
+    func resolve(in context: Context, where query: ModelQuery<Result>) -> EventLoopFuture<Result> {
         return self.resolve(in: context, where: query.query)
     }
 
-    public func resolveIfPresent(in context: Context, where query: ModelQuery<Result>) -> EventLoopFuture<IfPresentResult> {
+    func resolveIfPresent(in context: Context, where query: ModelQuery<Result>) -> EventLoopFuture<IfPresentResult> {
         return self.resolveIfPresent(in: context, where: query.query)
     }
 }
 
 public extension Resolvable where Result: Sequence, Result.Element: QueryableModel {
-    public func resolve(in context: Context, where query: ModelQuery<Result.Element>) -> EventLoopFuture<Result> {
+    func resolve(in context: Context, where query: ModelQuery<Result.Element>) -> EventLoopFuture<Result> {
         return self.resolve(in: context, where: query.query)
     }
 
-    public func resolveIfPresent(in context: Context, where query: ModelQuery<Result.Element>) -> EventLoopFuture<IfPresentResult> {
+    func resolveIfPresent(in context: Context, where query: ModelQuery<Result.Element>) -> EventLoopFuture<IfPresentResult> {
         return self.resolveIfPresent(in: context, where: query.query)
     }
 }

Sources/Meow/TypesafeQuerying.swift

@@ -42,7 +42,7 @@ public struct ModelQuery<M: QueryableModel> {
 }
 
 public extension AggregateCursor {
-    public func match<T>(_ query: ModelQuery<T>) -> AggregateCursor<Element> {
+    func match<T>(_ query: ModelQuery<T>) -> AggregateCursor<Element> {
         return self.match(query.query)
     }
 }

Sources/Meow/Updatable.swift

@@ -80,7 +80,7 @@ extension WritableKeyPath: OptionalKeyPath where Value: ExpressibleByNilLiteral
 
 public extension Decoder {
     /// - returns: An array containing the key paths that were updated
-    public func update<T: KeyPathQueryable>(_ instance: T, withAllowedKeyPaths keyPaths: [MeowWritableKeyPath]) throws -> [PartialKeyPath<T>] {
+    func update<T: KeyPathQueryable>(_ instance: T, withAllowedKeyPaths keyPaths: [MeowWritableKeyPath]) throws -> [PartialKeyPath<T>] {
         let container = try self.container(keyedBy: UpdateCodingKey.self)
 
         // must pass as inout to the KeyPath, hence the var
@@ -108,7 +108,7 @@ public extension JSONDecoder {
     }
 
     /// - returns: An array containing the key paths that were updated
-    public func update<T: QueryableModel>(_ instance: T, from data: Data, withAllowedKeyPaths keyPaths: [MeowWritableKeyPath]) throws -> [PartialKeyPath<T>] {
+    func update<T: QueryableModel>(_ instance: T, from data: Data, withAllowedKeyPaths keyPaths: [MeowWritableKeyPath]) throws -> [PartialKeyPath<T>] {
         // It seems not ideal that MeowWritableKeyPath currently is not restricted to Root == T
         assert(keyPaths.allSatisfy { $0 as? PartialKeyPath<T> != nil }, "Calling update for a certain model with allowed key paths of a different type does not make sense")
 

Sources/Meow/WrappedIdentifier.swift

@@ -2,9 +2,8 @@ internal class AnyInstanceIdentifier: Hashable {
 
     fileprivate init() {}
 
-    var hashValue: Int {
+    func hash(into hasher: inout Hasher) {
         assertionFailure("The HashValue implementation of AnyInstanceIdentifier should not be used")
-        return 0
     }
 
     static func == (lhs: AnyInstanceIdentifier, rhs: AnyInstanceIdentifier) -> Bool {
@@ -25,8 +24,9 @@ internal final class InstanceIdentifier<M: Model> : AnyInstanceIdentifier {
         super.init()
     }
 
-    override var hashValue: Int {
-        return ObjectIdentifier(M.self).hashValue ^ identifier.hashValue
+    override func hash(into hasher: inout Hasher) {
+        hasher.combine(ObjectIdentifier(M.self))
+        hasher.combine(identifier.hashValue)
     }
 
     override func equals(_ other: AnyInstanceIdentifier) -> Bool {