diff --git a/ios/Helpers/DictionaryCodingKey.swift b/ios/Helpers/DictionaryCodingKey.swift new file mode 100644 index 0000000..ab8267a --- /dev/null +++ b/ios/Helpers/DictionaryCodingKey.swift @@ -0,0 +1,48 @@ +//===----------------------------------------------------------------------===// +// +// This source file is largely a copy of code from Swift.org open source project's +// files JSONEncoder.swift and Codeable.swift. +// +// Unfortunately those files do not expose the internal _JSONEncoder and +// _JSONDecoder classes, which are in fact dictionary encoder/decoders and +// precisely what we want... +// +// The original code is copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors +// Licensed under Apache License v2.0 with Runtime Library Exception +// +// See https://swift.org/LICENSE.txt for license information +// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors +// +// Modifications and additional code here is copyright (c) 2018 Sam Deane, and +// is licensed under the same terms. +// +//===----------------------------------------------------------------------===// + +import Foundation + +internal struct DictionaryCodingKey : CodingKey { + public var stringValue: String + public var intValue: Int? + + public init?(stringValue: String) { + self.stringValue = stringValue + self.intValue = nil + } + + public init?(intValue: Int) { + self.stringValue = "\(intValue)" + self.intValue = intValue + } + + public init(stringValue: String, intValue: Int?) { + self.stringValue = stringValue + self.intValue = intValue + } + + internal init(index: Int) { + self.stringValue = "Index \(index)" + self.intValue = index + } + + internal static let `super` = DictionaryCodingKey(stringValue: "super")! +} diff --git a/ios/Helpers/DictionaryDecoder.swift b/ios/Helpers/DictionaryDecoder.swift new file mode 100644 index 0000000..25d2df2 --- /dev/null +++ b/ios/Helpers/DictionaryDecoder.swift @@ -0,0 +1,1369 @@ +//===----------------------------------------------------------------------===// +// +// This source file is largely a copy of code from Swift.org open source project's +// files JSONEncoder.swift and Codeable.swift. +// +// Unfortunately those files do not expose the internal _JSONEncoder and +// _JSONDecoder classes, which are in fact dictionary encoder/decoders and +// precisely what we want... +// +// The original code is copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors +// Licensed under Apache License v2.0 with Runtime Library Exception +// +// See https://swift.org/LICENSE.txt for license information +// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors +// +// Modifications and additional code here is copyright (c) 2018 Sam Deane, and +// is licensed under the same terms. +// +//===----------------------------------------------------------------------===// + +import Foundation + + +//===----------------------------------------------------------------------===// +// Dictionary Decoder +//===----------------------------------------------------------------------===// +/// `DictionaryDecoder` facilitates the decoding of Dictionary into semantic `Decodable` types. +open class DictionaryDecoder { + // MARK: Options + /// The strategy to use for decoding `Date` values. + public enum DateDecodingStrategy { + /// Defer to `Date` for decoding. This is the default strategy. + case deferredToDate + + /// Decode the `Date` as a UNIX timestamp from a Dictionary number. + case secondsSince1970 + + /// Decode the `Date` as UNIX millisecond timestamp from a Dictionary number. + case millisecondsSince1970 + + /// Decode the `Date` as an ISO-8601-formatted string (in RFC 3339 format). + @available(OSX 10.12, iOS 10.0, watchOS 3.0, tvOS 10.0, *) + case iso8601 + + /// Decode the `Date` as a string parsed by the given formatter. + case formatted(DateFormatter) + + /// Decode the `Date` as a custom value decoded by the given closure. + case custom((_ decoder: Decoder) throws -> Date) + } + + /// The strategy to use for decoding `Data` values. + public enum DataDecodingStrategy { + /// Defer to `Data` for decoding. + case deferredToData + + /// Decode the `Data` from a Base64-encoded string. This is the default strategy. + case base64 + + /// Decode the `Data` as a custom value decoded by the given closure. + case custom((_ decoder: Decoder) throws -> Data) + } + + /// The strategy to use for non-Dictionary-conforming floating-point values (IEEE 754 infinity and NaN). + public enum NonConformingFloatDecodingStrategy { + /// Throw upon encountering non-conforming values. This is the default strategy. + case `throw` + + /// Decode the values from the given representation strings. + case convertFromString(positiveInfinity: String, negativeInfinity: String, nan: String) + } + + /// The strategy to use when decoding missing keys. + public enum MissingValueDecodingStrategy { + /// Throw upon encountering missing values. + case `throw` + + /// Attempt to use a default value when encountering missing values for standard types. + case useStandardDefault + + /// Attempt to use a default value when encountering missing values. + /// The default value is read from the associated dictionary, keyed by the name of the type. + case useDefault(defaults : [String:Any]) + } + + /// The strategy to use for automatically changing the value of keys before decoding. + public enum KeyDecodingStrategy { + /// Use the keys specified by each type. This is the default strategy. + case useDefaultKeys + + /// Convert from "snake_case_keys" to "camelCaseKeys" before attempting to match a key with the one specified by each type. + /// + /// The conversion to upper case uses `Locale.system`, also known as the ICU "root" locale. This means the result is consistent regardless of the current user's locale and language preferences. + /// + /// Converting from snake case to camel case: + /// 1. Capitalizes the word starting after each `_` + /// 2. Removes all `_` + /// 3. Preserves starting and ending `_` (as these are often used to indicate private variables or other metadata). + /// For example, `one_two_three` becomes `oneTwoThree`. `_one_two_three_` becomes `_oneTwoThree_`. + /// + /// - Note: Using a key decoding strategy has a nominal performance cost, as each string key has to be inspected for the `_` character. + case convertFromSnakeCase + + /// Provide a custom conversion from the key in the encoded Dictionary to the keys specified by the decoded types. + /// The full path to the current decoding position is provided for context (in case you need to locate this key within the payload). The returned key is used in place of the last component in the coding path before decoding. + /// If the result of the conversion is a duplicate key, then only one value will be present in the container for the type to decode from. + case custom((_ codingPath: [CodingKey]) -> CodingKey) + + fileprivate static func _convertFromSnakeCase(_ stringKey: String) -> String { + guard !stringKey.isEmpty else { return stringKey } + + // Find the first non-underscore character + guard let firstNonUnderscore = stringKey.firstIndex(where: { $0 != "_" }) else { + // Reached the end without finding an _ + return stringKey + } + + // Find the last non-underscore character + var lastNonUnderscore = stringKey.index(before: stringKey.endIndex) + while lastNonUnderscore > firstNonUnderscore && stringKey[lastNonUnderscore] == "_" { + stringKey.formIndex(before: &lastNonUnderscore); + } + + let keyRange = firstNonUnderscore...lastNonUnderscore + let leadingUnderscoreRange = stringKey.startIndex..(_ type: T.Type, from dictionary: NSDictionary) throws -> T { + let decoder = _DictionaryDecoder(referencing: dictionary, options: self.options) + guard let value = try decoder.unbox(dictionary, as: type) else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: [], debugDescription: "The given data did not contain a top-level value.")) + } + + return value + } + + /// Decodes a top-level value of the given type from the given Dictionary representation. + /// + /// - parameter type: The type of the value to decode. + /// - parameter data: The data to decode from. + /// - returns: A value of the requested type. + /// - throws: `DecodingError.dataCorrupted` if values requested from the payload are corrupted, or if the given data is not valid Dictionary. + /// - throws: An error if any value throws an error during decoding. + open func decode(_ type: T.Type, from dictionary: [String:Any]) throws -> T { + let decoder = _DictionaryDecoder(referencing: dictionary, options: self.options) + guard let value = try decoder.unbox(dictionary, as: type) else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: [], debugDescription: "The given data did not contain a top-level value.")) + } + + return value + } + +} + +// MARK: - _DictionaryDecoder +fileprivate class _DictionaryDecoder : Decoder { + // MARK: Properties + /// The decoder's storage. + fileprivate var storage: _DictionaryDecodingStorage + + /// Options set on the top-level decoder. + fileprivate let options: DictionaryDecoder._Options + + /// The path to the current point in encoding. + fileprivate(set) public var codingPath: [CodingKey] + + /// Contextual user-provided information for use during encoding. + public var userInfo: [CodingUserInfoKey : Any] { + return self.options.userInfo + } + + // MARK: - Initialization + /// Initializes `self` with the given top-level container and options. + fileprivate init(referencing container: Any, at codingPath: [CodingKey] = [], options: DictionaryDecoder._Options) { + self.storage = _DictionaryDecodingStorage() + self.storage.push(container: container) + self.codingPath = codingPath + self.options = options + } + + // MARK: - Decoder Methods + public func container(keyedBy type: Key.Type) throws -> KeyedDecodingContainer { + guard !(self.storage.topContainer is NSNull) else { + throw DecodingError.valueNotFound(KeyedDecodingContainer.self, + DecodingError.Context(codingPath: self.codingPath, + debugDescription: "Cannot get keyed decoding container -- found null value instead.")) + } + + guard let topContainer = self.storage.topContainer as? [String : Any] else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: [String : Any].self, reality: self.storage.topContainer) + } + + let container = DictionaryCodingKeyedDecodingContainer(referencing: self, wrapping: topContainer) + return KeyedDecodingContainer(container) + } + + public func unkeyedContainer() throws -> UnkeyedDecodingContainer { + guard !(self.storage.topContainer is NSNull) else { + throw DecodingError.valueNotFound(UnkeyedDecodingContainer.self, + DecodingError.Context(codingPath: self.codingPath, + debugDescription: "Cannot get unkeyed decoding container -- found null value instead.")) + } + + guard let topContainer = self.storage.topContainer as? [Any] else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: [Any].self, reality: self.storage.topContainer) + } + + return _DictionaryUnkeyedDecodingContainer(referencing: self, wrapping: topContainer) + } + + public func singleValueContainer() throws -> SingleValueDecodingContainer { + return self + } +} + +// MARK: - Decoding Storage +fileprivate struct _DictionaryDecodingStorage { + // MARK: Properties + /// The container stack. + /// Elements may be any one of the Dictionary types (NSNull, NSNumber, String, Array, [String : Any]). + private(set) fileprivate var containers: [Any] = [] + + // MARK: - Initialization + /// Initializes `self` with no containers. + fileprivate init() {} + + // MARK: - Modifying the Stack + fileprivate var count: Int { + return self.containers.count + } + + fileprivate var topContainer: Any { + precondition(self.containers.count > 0, "Empty container stack.") + return self.containers.last! + } + + fileprivate mutating func push(container: Any) { + self.containers.append(container) + } + + fileprivate mutating func popContainer() { + precondition(self.containers.count > 0, "Empty container stack.") + self.containers.removeLast() + } +} + +// MARK: Decoding Containers +fileprivate struct DictionaryCodingKeyedDecodingContainer : KeyedDecodingContainerProtocol { + typealias Key = K + + // MARK: Properties + /// A reference to the decoder we're reading from. + private let decoder: _DictionaryDecoder + + /// A reference to the container we're reading from. + private let container: [String : Any] + + /// The path of coding keys taken to get to this point in decoding. + private(set) public var codingPath: [CodingKey] + + // MARK: - Initialization + /// Initializes `self` by referencing the given decoder and container. + fileprivate init(referencing decoder: _DictionaryDecoder, wrapping container: [String : Any]) { + self.decoder = decoder + switch decoder.options.keyDecodingStrategy { + case .useDefaultKeys: + self.container = container + case .convertFromSnakeCase: + // Convert the snake case keys in the container to camel case. + // If we hit a duplicate key after conversion, then we'll use the first one we saw. Effectively an undefined behavior with Dictionary dictionaries. + self.container = Dictionary(container.map { + key, value in (DictionaryDecoder.KeyDecodingStrategy._convertFromSnakeCase(key), value) + }, uniquingKeysWith: { (first, _) in first }) + case .custom(let converter): + self.container = Dictionary(container.map { + key, value in (converter(decoder.codingPath + [DictionaryCodingKey(stringValue: key, intValue: nil)]).stringValue, value) + }, uniquingKeysWith: { (first, _) in first }) + } + self.codingPath = decoder.codingPath + } + + // MARK: - KeyedDecodingContainerProtocol Methods + public var allKeys: [Key] { + #if swift(>=4.1) + return self.container.keys.compactMap { Key(stringValue: $0) } + #else + return self.container.keys.flatMap { Key(stringValue: $0) } + #endif + } + + public func contains(_ key: Key) -> Bool { + return self.container[key.stringValue] != nil + } + + internal func notFoundError(key: Key) -> DecodingError { + return DecodingError.keyNotFound(key, DecodingError.Context(codingPath: self.decoder.codingPath, debugDescription: "No value associated with key \(_errorDescription(of: key)).")) + } + + internal func nullFoundError(type: T.Type) -> DecodingError { + return DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath, debugDescription: "Expected \(type) value but found null instead.")) + } + + private func _errorDescription(of key: CodingKey) -> String { + switch decoder.options.keyDecodingStrategy { + case .convertFromSnakeCase: + // In this case we can attempt to recover the original value by reversing the transform + let original = key.stringValue + let converted = DictionaryEncoder.KeyEncodingStrategy._convertToSnakeCase(original) + if converted == original { + return "\(key) (\"\(original)\")" + } else { + return "\(key) (\"\(original)\"), converted to \(converted)" + } + default: + // Otherwise, just report the converted string + return "\(key) (\"\(key.stringValue)\")" + } + } + + public func decodeNil(forKey key: Key) throws -> Bool { + guard let entry = self.container[key.stringValue] else { + throw notFoundError(key: key) + } + + return entry is NSNull + } + + internal func decode(_ type: T.Type, forKey key: Key) throws -> T { + guard let entry = self.container[key.stringValue] else { + switch (decoder.options.missingValueDecodingStrategy) { + case let .useDefault(defaults): + let defaultKey = "\(type)" + if let def = defaults[defaultKey] as? T { + return def + } + default: + break + } + + throw notFoundError(key: key) + } + + self.decoder.codingPath.append(key) + defer { self.decoder.codingPath.removeLast() } + + guard let value = try self.decoder.unbox(entry, as: type) else { + throw nullFoundError(type: type) + } + + return value + } + + public func nestedContainer(keyedBy type: NestedKey.Type, forKey key: Key) throws -> KeyedDecodingContainer { + self.decoder.codingPath.append(key) + defer { self.decoder.codingPath.removeLast() } + + guard let value = self.container[key.stringValue] else { + throw DecodingError.keyNotFound(key, + DecodingError.Context(codingPath: self.codingPath, + debugDescription: "Cannot get \(KeyedDecodingContainer.self) -- no value found for key \(_errorDescription(of: key))")) + } + + guard let dictionary = value as? [String : Any] else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: [String : Any].self, reality: value) + } + + let container = DictionaryCodingKeyedDecodingContainer(referencing: self.decoder, wrapping: dictionary) + return KeyedDecodingContainer(container) + } + + public func nestedUnkeyedContainer(forKey key: Key) throws -> UnkeyedDecodingContainer { + self.decoder.codingPath.append(key) + defer { self.decoder.codingPath.removeLast() } + + guard let value = self.container[key.stringValue] else { + throw DecodingError.keyNotFound(key, + DecodingError.Context(codingPath: self.codingPath, + debugDescription: "Cannot get UnkeyedDecodingContainer -- no value found for key \(_errorDescription(of: key))")) + } + + guard let array = value as? [Any] else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: [Any].self, reality: value) + } + + return _DictionaryUnkeyedDecodingContainer(referencing: self.decoder, wrapping: array) + } + + private func _superDecoder(forKey key: CodingKey) throws -> Decoder { + self.decoder.codingPath.append(key) + defer { self.decoder.codingPath.removeLast() } + + let value: Any = self.container[key.stringValue] ?? NSNull() + return _DictionaryDecoder(referencing: value, at: self.decoder.codingPath, options: self.decoder.options) + } + + public func superDecoder() throws -> Decoder { + return try _superDecoder(forKey: DictionaryCodingKey.super) + } + + public func superDecoder(forKey key: Key) throws -> Decoder { + return try _superDecoder(forKey: key) + } +} + +fileprivate struct _DictionaryUnkeyedDecodingContainer : UnkeyedDecodingContainer { + // MARK: Properties + /// A reference to the decoder we're reading from. + private let decoder: _DictionaryDecoder + + /// A reference to the container we're reading from. + private let container: [Any] + + /// The path of coding keys taken to get to this point in decoding. + private(set) public var codingPath: [CodingKey] + + /// The index of the element we're about to decode. + private(set) public var currentIndex: Int + + // MARK: - Initialization + /// Initializes `self` by referencing the given decoder and container. + fileprivate init(referencing decoder: _DictionaryDecoder, wrapping container: [Any]) { + self.decoder = decoder + self.container = container + self.codingPath = decoder.codingPath + self.currentIndex = 0 + } + + // MARK: - UnkeyedDecodingContainer Methods + public var count: Int? { + return self.container.count + } + + public var isAtEnd: Bool { + return self.currentIndex >= self.count! + } + + public mutating func decodeNil() throws -> Bool { + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(Any?.self, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Unkeyed container is at end.")) + } + + if self.container[self.currentIndex] is NSNull { + self.currentIndex += 1 + return true + } else { + return false + } + } + + public mutating func decode(_ type: Bool.Type) throws -> Bool { + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Unkeyed container is at end.")) + } + + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard let decoded = try self.decoder.unbox(self.container[self.currentIndex], as: Bool.self) else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Expected \(type) but found null instead.")) + } + + self.currentIndex += 1 + return decoded + } + + public mutating func decode(_ type: Int.Type) throws -> Int { + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Unkeyed container is at end.")) + } + + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard let decoded = try self.decoder.unbox(self.container[self.currentIndex], as: Int.self) else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Expected \(type) but found null instead.")) + } + + self.currentIndex += 1 + return decoded + } + + public mutating func decode(_ type: Int8.Type) throws -> Int8 { + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Unkeyed container is at end.")) + } + + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard let decoded = try self.decoder.unbox(self.container[self.currentIndex], as: Int8.self) else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Expected \(type) but found null instead.")) + } + + self.currentIndex += 1 + return decoded + } + + public mutating func decode(_ type: Int16.Type) throws -> Int16 { + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Unkeyed container is at end.")) + } + + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard let decoded = try self.decoder.unbox(self.container[self.currentIndex], as: Int16.self) else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Expected \(type) but found null instead.")) + } + + self.currentIndex += 1 + return decoded + } + + public mutating func decode(_ type: Int32.Type) throws -> Int32 { + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Unkeyed container is at end.")) + } + + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard let decoded = try self.decoder.unbox(self.container[self.currentIndex], as: Int32.self) else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Expected \(type) but found null instead.")) + } + + self.currentIndex += 1 + return decoded + } + + public mutating func decode(_ type: Int64.Type) throws -> Int64 { + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Unkeyed container is at end.")) + } + + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard let decoded = try self.decoder.unbox(self.container[self.currentIndex], as: Int64.self) else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Expected \(type) but found null instead.")) + } + + self.currentIndex += 1 + return decoded + } + + public mutating func decode(_ type: UInt.Type) throws -> UInt { + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Unkeyed container is at end.")) + } + + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard let decoded = try self.decoder.unbox(self.container[self.currentIndex], as: UInt.self) else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Expected \(type) but found null instead.")) + } + + self.currentIndex += 1 + return decoded + } + + public mutating func decode(_ type: UInt8.Type) throws -> UInt8 { + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Unkeyed container is at end.")) + } + + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard let decoded = try self.decoder.unbox(self.container[self.currentIndex], as: UInt8.self) else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Expected \(type) but found null instead.")) + } + + self.currentIndex += 1 + return decoded + } + + public mutating func decode(_ type: UInt16.Type) throws -> UInt16 { + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Unkeyed container is at end.")) + } + + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard let decoded = try self.decoder.unbox(self.container[self.currentIndex], as: UInt16.self) else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Expected \(type) but found null instead.")) + } + + self.currentIndex += 1 + return decoded + } + + public mutating func decode(_ type: UInt32.Type) throws -> UInt32 { + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Unkeyed container is at end.")) + } + + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard let decoded = try self.decoder.unbox(self.container[self.currentIndex], as: UInt32.self) else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Expected \(type) but found null instead.")) + } + + self.currentIndex += 1 + return decoded + } + + public mutating func decode(_ type: UInt64.Type) throws -> UInt64 { + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Unkeyed container is at end.")) + } + + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard let decoded = try self.decoder.unbox(self.container[self.currentIndex], as: UInt64.self) else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Expected \(type) but found null instead.")) + } + + self.currentIndex += 1 + return decoded + } + + public mutating func decode(_ type: Float.Type) throws -> Float { + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Unkeyed container is at end.")) + } + + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard let decoded = try self.decoder.unbox(self.container[self.currentIndex], as: Float.self) else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Expected \(type) but found null instead.")) + } + + self.currentIndex += 1 + return decoded + } + + public mutating func decode(_ type: Double.Type) throws -> Double { + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Unkeyed container is at end.")) + } + + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard let decoded = try self.decoder.unbox(self.container[self.currentIndex], as: Double.self) else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Expected \(type) but found null instead.")) + } + + self.currentIndex += 1 + return decoded + } + + public mutating func decode(_ type: String.Type) throws -> String { + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Unkeyed container is at end.")) + } + + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard let decoded = try self.decoder.unbox(self.container[self.currentIndex], as: String.self) else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Expected \(type) but found null instead.")) + } + + self.currentIndex += 1 + return decoded + } + + public mutating func decode(_ type: T.Type) throws -> T { + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Unkeyed container is at end.")) + } + + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard let decoded = try self.decoder.unbox(self.container[self.currentIndex], as: type) else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.decoder.codingPath + [DictionaryCodingKey(index: self.currentIndex)], debugDescription: "Expected \(type) but found null instead.")) + } + + self.currentIndex += 1 + return decoded + } + + public mutating func nestedContainer(keyedBy type: NestedKey.Type) throws -> KeyedDecodingContainer { + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(KeyedDecodingContainer.self, + DecodingError.Context(codingPath: self.codingPath, + debugDescription: "Cannot get nested keyed container -- unkeyed container is at end.")) + } + + let value = self.container[self.currentIndex] + guard !(value is NSNull) else { + throw DecodingError.valueNotFound(KeyedDecodingContainer.self, + DecodingError.Context(codingPath: self.codingPath, + debugDescription: "Cannot get keyed decoding container -- found null value instead.")) + } + + guard let dictionary = value as? [String : Any] else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: [String : Any].self, reality: value) + } + + self.currentIndex += 1 + let container = DictionaryCodingKeyedDecodingContainer(referencing: self.decoder, wrapping: dictionary) + return KeyedDecodingContainer(container) + } + + public mutating func nestedUnkeyedContainer() throws -> UnkeyedDecodingContainer { + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(UnkeyedDecodingContainer.self, + DecodingError.Context(codingPath: self.codingPath, + debugDescription: "Cannot get nested keyed container -- unkeyed container is at end.")) + } + + let value = self.container[self.currentIndex] + guard !(value is NSNull) else { + throw DecodingError.valueNotFound(UnkeyedDecodingContainer.self, + DecodingError.Context(codingPath: self.codingPath, + debugDescription: "Cannot get keyed decoding container -- found null value instead.")) + } + + guard let array = value as? [Any] else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: [Any].self, reality: value) + } + + self.currentIndex += 1 + return _DictionaryUnkeyedDecodingContainer(referencing: self.decoder, wrapping: array) + } + + public mutating func superDecoder() throws -> Decoder { + self.decoder.codingPath.append(DictionaryCodingKey(index: self.currentIndex)) + defer { self.decoder.codingPath.removeLast() } + + guard !self.isAtEnd else { + throw DecodingError.valueNotFound(Decoder.self, + DecodingError.Context(codingPath: self.codingPath, + debugDescription: "Cannot get superDecoder() -- unkeyed container is at end.")) + } + + let value = self.container[self.currentIndex] + self.currentIndex += 1 + return _DictionaryDecoder(referencing: value, at: self.decoder.codingPath, options: self.decoder.options) + } +} + +extension _DictionaryDecoder : SingleValueDecodingContainer { + // MARK: SingleValueDecodingContainer Methods + private func expectNonNull(_ type: T.Type) throws { + guard !self.decodeNil() else { + throw DecodingError.valueNotFound(type, DecodingError.Context(codingPath: self.codingPath, debugDescription: "Expected \(type) but found null value instead.")) + } + } + + public func decodeNil() -> Bool { + return self.storage.topContainer is NSNull + } + + public func decode(_ type: Bool.Type) throws -> Bool { + try expectNonNull(Bool.self) + return try self.unbox(self.storage.topContainer, as: Bool.self)! + } + + public func decode(_ type: Int.Type) throws -> Int { + try expectNonNull(Int.self) + return try self.unbox(self.storage.topContainer, as: Int.self)! + } + + public func decode(_ type: Int8.Type) throws -> Int8 { + try expectNonNull(Int8.self) + return try self.unbox(self.storage.topContainer, as: Int8.self)! + } + + public func decode(_ type: Int16.Type) throws -> Int16 { + try expectNonNull(Int16.self) + return try self.unbox(self.storage.topContainer, as: Int16.self)! + } + + public func decode(_ type: Int32.Type) throws -> Int32 { + try expectNonNull(Int32.self) + return try self.unbox(self.storage.topContainer, as: Int32.self)! + } + + public func decode(_ type: Int64.Type) throws -> Int64 { + try expectNonNull(Int64.self) + return try self.unbox(self.storage.topContainer, as: Int64.self)! + } + + public func decode(_ type: UInt.Type) throws -> UInt { + try expectNonNull(UInt.self) + return try self.unbox(self.storage.topContainer, as: UInt.self)! + } + + public func decode(_ type: UInt8.Type) throws -> UInt8 { + try expectNonNull(UInt8.self) + return try self.unbox(self.storage.topContainer, as: UInt8.self)! + } + + public func decode(_ type: UInt16.Type) throws -> UInt16 { + try expectNonNull(UInt16.self) + return try self.unbox(self.storage.topContainer, as: UInt16.self)! + } + + public func decode(_ type: UInt32.Type) throws -> UInt32 { + try expectNonNull(UInt32.self) + return try self.unbox(self.storage.topContainer, as: UInt32.self)! + } + + public func decode(_ type: UInt64.Type) throws -> UInt64 { + try expectNonNull(UInt64.self) + return try self.unbox(self.storage.topContainer, as: UInt64.self)! + } + + public func decode(_ type: Float.Type) throws -> Float { + try expectNonNull(Float.self) + return try self.unbox(self.storage.topContainer, as: Float.self)! + } + + public func decode(_ type: Double.Type) throws -> Double { + try expectNonNull(Double.self) + return try self.unbox(self.storage.topContainer, as: Double.self)! + } + + public func decode(_ type: String.Type) throws -> String { + try expectNonNull(String.self) + return try self.unbox(self.storage.topContainer, as: String.self)! + } + + public func decode(_ type: T.Type) throws -> T { + try expectNonNull(type) + return try self.unbox(self.storage.topContainer, as: type)! + } +} + +// MARK: - Concrete Value Representations +extension _DictionaryDecoder { + /// Returns the given value unboxed from a container. + fileprivate func unbox(_ value: Any, as type: Bool.Type) throws -> Bool? { + guard !(value is NSNull) else { return nil } + + if let number = value as? NSNumber { + + if number === kCFBooleanTrue as NSNumber { + return true + } else if number === kCFBooleanFalse as NSNumber { + return false + } else { + return number != 0 // TODO: Add a flag to disallow non-boolean numbers? + } + + /* FIXME: If swift-corelibs-foundation doesn't change to use NSNumber, this code path will need to be included and tested: + } else if let bool = value as? Bool { + return bool + */ + + } + + throw DecodingError._typeMismatch(at: self.codingPath, expectation: type, reality: value) + } + + fileprivate func unbox(_ value: Any, as type: Int.Type) throws -> Int? { + guard !(value is NSNull) else { return nil } + + guard let number = value as? NSNumber, number !== kCFBooleanTrue, number !== kCFBooleanFalse else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: type, reality: value) + } + + let int = number.intValue + guard NSNumber(value: int) == number else { + throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: self.codingPath, debugDescription: "Parsed Dictionary number <\(number)> does not fit in \(type).")) + } + + return int + } + + fileprivate func unbox(_ value: Any, as type: Int8.Type) throws -> Int8? { + guard !(value is NSNull) else { return nil } + + guard let number = value as? NSNumber, number !== kCFBooleanTrue, number !== kCFBooleanFalse else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: type, reality: value) + } + + let int8 = number.int8Value + guard NSNumber(value: int8) == number else { + throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: self.codingPath, debugDescription: "Parsed Dictionary number <\(number)> does not fit in \(type).")) + } + + return int8 + } + + fileprivate func unbox(_ value: Any, as type: Int16.Type) throws -> Int16? { + guard !(value is NSNull) else { return nil } + + guard let number = value as? NSNumber, number !== kCFBooleanTrue, number !== kCFBooleanFalse else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: type, reality: value) + } + + let int16 = number.int16Value + guard NSNumber(value: int16) == number else { + throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: self.codingPath, debugDescription: "Parsed Dictionary number <\(number)> does not fit in \(type).")) + } + + return int16 + } + + fileprivate func unbox(_ value: Any, as type: Int32.Type) throws -> Int32? { + guard !(value is NSNull) else { return nil } + + guard let number = value as? NSNumber, number !== kCFBooleanTrue, number !== kCFBooleanFalse else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: type, reality: value) + } + + let int32 = number.int32Value + guard NSNumber(value: int32) == number else { + throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: self.codingPath, debugDescription: "Parsed Dictionary number <\(number)> does not fit in \(type).")) + } + + return int32 + } + + fileprivate func unbox(_ value: Any, as type: Int64.Type) throws -> Int64? { + guard !(value is NSNull) else { return nil } + + guard let number = value as? NSNumber, number !== kCFBooleanTrue, number !== kCFBooleanFalse else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: type, reality: value) + } + + let int64 = number.int64Value + guard NSNumber(value: int64) == number else { + throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: self.codingPath, debugDescription: "Parsed Dictionary number <\(number)> does not fit in \(type).")) + } + + return int64 + } + + fileprivate func unbox(_ value: Any, as type: UInt.Type) throws -> UInt? { + guard !(value is NSNull) else { return nil } + + guard let number = value as? NSNumber, number !== kCFBooleanTrue, number !== kCFBooleanFalse else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: type, reality: value) + } + + let uint = number.uintValue + guard NSNumber(value: uint) == number else { + throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: self.codingPath, debugDescription: "Parsed Dictionary number <\(number)> does not fit in \(type).")) + } + + return uint + } + + fileprivate func unbox(_ value: Any, as type: UInt8.Type) throws -> UInt8? { + guard !(value is NSNull) else { return nil } + + guard let number = value as? NSNumber, number !== kCFBooleanTrue, number !== kCFBooleanFalse else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: type, reality: value) + } + + let uint8 = number.uint8Value + guard NSNumber(value: uint8) == number else { + throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: self.codingPath, debugDescription: "Parsed Dictionary number <\(number)> does not fit in \(type).")) + } + + return uint8 + } + + fileprivate func unbox(_ value: Any, as type: UInt16.Type) throws -> UInt16? { + guard !(value is NSNull) else { return nil } + + guard let number = value as? NSNumber, number !== kCFBooleanTrue, number !== kCFBooleanFalse else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: type, reality: value) + } + + let uint16 = number.uint16Value + guard NSNumber(value: uint16) == number else { + throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: self.codingPath, debugDescription: "Parsed Dictionary number <\(number)> does not fit in \(type).")) + } + + return uint16 + } + + fileprivate func unbox(_ value: Any, as type: UInt32.Type) throws -> UInt32? { + guard !(value is NSNull) else { return nil } + + guard let number = value as? NSNumber, number !== kCFBooleanTrue, number !== kCFBooleanFalse else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: type, reality: value) + } + + let uint32 = number.uint32Value + guard NSNumber(value: uint32) == number else { + throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: self.codingPath, debugDescription: "Parsed Dictionary number <\(number)> does not fit in \(type).")) + } + + return uint32 + } + + fileprivate func unbox(_ value: Any, as type: UInt64.Type) throws -> UInt64? { + guard !(value is NSNull) else { return nil } + + guard let number = value as? NSNumber, number !== kCFBooleanTrue, number !== kCFBooleanFalse else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: type, reality: value) + } + + let uint64 = number.uint64Value + guard NSNumber(value: uint64) == number else { + throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: self.codingPath, debugDescription: "Parsed Dictionary number <\(number)> does not fit in \(type).")) + } + + return uint64 + } + + fileprivate func unbox(_ value: Any, as type: Float.Type) throws -> Float? { + guard !(value is NSNull) else { return nil } + + if let number = value as? NSNumber, number !== kCFBooleanTrue, number !== kCFBooleanFalse { + // We are willing to return a Float by losing precision: + // * If the original value was integral, + // * and the integral value was > Float.greatestFiniteMagnitude, we will fail + // * and the integral value was <= Float.greatestFiniteMagnitude, we are willing to lose precision past 2^24 + // * If it was a Float, you will get back the precise value + // * If it was a Double or Decimal, you will get back the nearest approximation if it will fit + let double = number.doubleValue + guard abs(double) <= Double(Float.greatestFiniteMagnitude) else { + throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: self.codingPath, debugDescription: "Parsed Dictionary number \(number) does not fit in \(type).")) + } + + return Float(double) + + /* FIXME: If swift-corelibs-foundation doesn't change to use NSNumber, this code path will need to be included and tested: + } else if let double = value as? Double { + if abs(double) <= Double(Float.max) { + return Float(double) + } + overflow = true + } else if let int = value as? Int { + if let float = Float(exactly: int) { + return float + } + overflow = true + */ + + } else if let string = value as? String, + case .convertFromString(let posInfString, let negInfString, let nanString) = self.options.nonConformingFloatDecodingStrategy { + if string == posInfString { + return Float.infinity + } else if string == negInfString { + return -Float.infinity + } else if string == nanString { + return Float.nan + } + } + + throw DecodingError._typeMismatch(at: self.codingPath, expectation: type, reality: value) + } + + fileprivate func unbox(_ value: Any, as type: Double.Type) throws -> Double? { + guard !(value is NSNull) else { return nil } + + if let number = value as? NSNumber, number !== kCFBooleanTrue, number !== kCFBooleanFalse { + // We are always willing to return the number as a Double: + // * If the original value was integral, it is guaranteed to fit in a Double; we are willing to lose precision past 2^53 if you encoded a UInt64 but requested a Double + // * If it was a Float or Double, you will get back the precise value + // * If it was Decimal, you will get back the nearest approximation + return number.doubleValue + + /* FIXME: If swift-corelibs-foundation doesn't change to use NSNumber, this code path will need to be included and tested: + } else if let double = value as? Double { + return double + } else if let int = value as? Int { + if let double = Double(exactly: int) { + return double + } + overflow = true + */ + + } else if let string = value as? String, + case .convertFromString(let posInfString, let negInfString, let nanString) = self.options.nonConformingFloatDecodingStrategy { + if string == posInfString { + return Double.infinity + } else if string == negInfString { + return -Double.infinity + } else if string == nanString { + return Double.nan + } + } + + throw DecodingError._typeMismatch(at: self.codingPath, expectation: type, reality: value) + } + + fileprivate func unbox(_ value: Any, as type: String.Type) throws -> String? { + guard !(value is NSNull) else { return nil } + + if let url = value as? URL { + return url.absoluteString + } + + if let uuid = value as? UUID { + return uuid.uuidString + } + + guard let string = value as? String else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: type, reality: value) + } + + return string + } + + fileprivate func unbox(_ value: Any, as type: UUID.Type) throws -> UUID? { + guard !(value is NSNull) else { return nil } + + if let uuid = value as? UUID { + return uuid + } + + if let string = value as? String { + return UUID(uuidString: string) + } + + let cfType = CFGetTypeID(value as CFTypeRef) // NB this could be dangerous - we're assuming that it's ok to call CFGetTypeID with the value, which may not be true + if cfType == CFUUIDGetTypeID() { + let cfValue = value as! CFUUID + let string = CFUUIDCreateString(kCFAllocatorDefault, cfValue) as String + return UUID(uuidString: string) + } + + throw DecodingError._typeMismatch(at: self.codingPath, expectation: type, reality: value) + } + + fileprivate func unbox(_ value: Any, as type: Date.Type) throws -> Date? { + guard !(value is NSNull) else { return nil } + + switch self.options.dateDecodingStrategy { + case .deferredToDate: + self.storage.push(container: value) + defer { self.storage.popContainer() } + return try Date(from: self) + + case .secondsSince1970: + let double = try self.unbox(value, as: Double.self)! + return Date(timeIntervalSince1970: double) + + case .millisecondsSince1970: + let double = try self.unbox(value, as: Double.self)! + return Date(timeIntervalSince1970: double / 1000.0) + + case .iso8601: + if #available(OSX 10.12, iOS 10.0, watchOS 3.0, tvOS 10.0, *) { + let string = try self.unbox(value, as: String.self)! + guard let date = _iso8601Formatter.date(from: string) else { + throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: self.codingPath, debugDescription: "Expected date string to be ISO8601-formatted.")) + } + + return date + } else { + fatalError("ISO8601DateFormatter is unavailable on this platform.") + } + + case .formatted(let formatter): + let string = try self.unbox(value, as: String.self)! + guard let date = formatter.date(from: string) else { + throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: self.codingPath, debugDescription: "Date string does not match format expected by formatter.")) + } + + return date + + case .custom(let closure): + self.storage.push(container: value) + defer { self.storage.popContainer() } + return try closure(self) + } + } + + fileprivate func unbox(_ value: Any, as type: Data.Type) throws -> Data? { + guard !(value is NSNull) else { return nil } + + switch self.options.dataDecodingStrategy { + case .deferredToData: + self.storage.push(container: value) + defer { self.storage.popContainer() } + return try Data(from: self) + + case .base64: + guard let string = value as? String else { + throw DecodingError._typeMismatch(at: self.codingPath, expectation: type, reality: value) + } + + guard let data = Data(base64Encoded: string) else { + throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: self.codingPath, debugDescription: "Encountered Data is not valid Base64.")) + } + + return data + + case .custom(let closure): + self.storage.push(container: value) + defer { self.storage.popContainer() } + return try closure(self) + } + } + + fileprivate func unbox(_ value: Any, as type: Decimal.Type) throws -> Decimal? { + guard !(value is NSNull) else { return nil } + + // Attempt to bridge from NSDecimalNumber. + if let decimal = value as? Decimal { + return decimal + } else { + let doubleValue = try self.unbox(value, as: Double.self)! + return Decimal(doubleValue) + } + } + + fileprivate func unbox(_ value: Any, as type: T.Type) throws -> T? { + if type == Date.self || type == NSDate.self { + return try self.unbox(value, as: Date.self) as? T + } else if type == Data.self || type == NSData.self { + return try self.unbox(value, as: Data.self) as? T + } else if type == UUID.self || type == CFUUID.self { + return try self.unbox(value, as: UUID.self) as? T + } else if type == URL.self || type == NSURL.self { + guard let urlString = try self.unbox(value, as: String.self) else { + return nil + } + + guard let url = URL(string: urlString) else { + throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: self.codingPath, + debugDescription: "Invalid URL string.")) + } + + return (url as! T) + } else if type == Decimal.self || type == NSDecimalNumber.self { + return try self.unbox(value, as: Decimal.self) as? T + } else { + self.storage.push(container: value) + defer { self.storage.popContainer() } + return try type.init(from: self) + } + } +} + +//===----------------------------------------------------------------------===// +// Shared ISO8601 Date Formatter +//===----------------------------------------------------------------------===// +// NOTE: This value is implicitly lazy and _must_ be lazy. We're compiled against the latest SDK (w/ ISO8601DateFormatter), but linked against whichever Foundation the user has. ISO8601DateFormatter might not exist, so we better not hit this code path on an older OS. +@available(OSX 10.12, iOS 10.0, watchOS 3.0, tvOS 10.0, *) +internal var _iso8601Formatter: ISO8601DateFormatter = { + let formatter = ISO8601DateFormatter() + formatter.formatOptions = .withInternetDateTime + return formatter +}() + + +#if canImport(Combine) +import Combine + +extension DictionaryDecoder: TopLevelDecoder { + public typealias Input = [String: Any] +} +#endif \ No newline at end of file diff --git a/ios/Helpers/DictionaryEncoder.swift b/ios/Helpers/DictionaryEncoder.swift new file mode 100644 index 0000000..76de6fc --- /dev/null +++ b/ios/Helpers/DictionaryEncoder.swift @@ -0,0 +1,923 @@ +//===----------------------------------------------------------------------===// +// +// This source file is largely a copy of code from Swift.org open source project's +// files JSONEncoder.swift and Codeable.swift. +// +// Unfortunately those files do not expose the internal _JSONEncoder and +// _JSONDecoder classes, which are in fact dictionary encoder/decoders and +// precisely what we want... +// +// The original code is copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors +// Licensed under Apache License v2.0 with Runtime Library Exception +// +// See https://swift.org/LICENSE.txt for license information +// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors +// +// Modifications and additional code here is copyright (c) 2018 Sam Deane, and +// is licensed under the same terms. +// +//===----------------------------------------------------------------------===// + +import Foundation + + +//===----------------------------------------------------------------------===// +// Dictionary Encoder +//===----------------------------------------------------------------------===// + +/// `DictionaryEncoder` facilitates the encoding of `Encodable` values into Dictionary. +open class DictionaryEncoder { + // MARK: Options + + /// The strategy to use for encoding `Date` values. + public enum DateEncodingStrategy { + /// Defer to `Date` for choosing an encoding. This is the default strategy. + case deferredToDate + + /// Encode the `Date` as a UNIX timestamp (as a Dictionary number). + case secondsSince1970 + + /// Encode the `Date` as UNIX millisecond timestamp (as a Dictionary number). + case millisecondsSince1970 + + /// Encode the `Date` as an ISO-8601-formatted string (in RFC 3339 format). + @available(OSX 10.12, iOS 10.0, watchOS 3.0, tvOS 10.0, *) + case iso8601 + + /// Encode the `Date` as a string formatted by the given formatter. + case formatted(DateFormatter) + + /// Encode the `Date` as a custom value encoded by the given closure. + /// + /// If the closure fails to encode a value into the given encoder, the encoder will encode an empty automatic container in its place. + case custom((Date, Encoder) throws -> Void) + } + + /// The strategy to use for encoding `Data` values. + public enum DataEncodingStrategy { + /// Defer to `Data` for choosing an encoding. + case deferredToData + + /// Encoded the `Data` as a Base64-encoded string. This is the default strategy. + case base64 + + /// Encode the `Data` as a custom value encoded by the given closure. + /// + /// If the closure fails to encode a value into the given encoder, the encoder will encode an empty automatic container in its place. + case custom((Data, Encoder) throws -> Void) + } + + /// The strategy to use for non-Dictionary-conforming floating-point values (IEEE 754 infinity and NaN). + public enum NonConformingFloatEncodingStrategy { + /// Throw upon encountering non-conforming values. This is the default strategy. + case `throw` + + /// Encode the values using the given representation strings. + case convertToString(positiveInfinity: String, negativeInfinity: String, nan: String) + } + + /// The strategy to use for automatically changing the value of keys before encoding. + public enum KeyEncodingStrategy { + /// Use the keys specified by each type. This is the default strategy. + case useDefaultKeys + + /// Convert from "camelCaseKeys" to "snake_case_keys" before writing a key to Dictionary payload. + /// + /// Capital characters are determined by testing membership in `CharacterSet.uppercaseLetters` and `CharacterSet.lowercaseLetters` (Unicode General Categories Lu and Lt). + /// The conversion to lower case uses `Locale.system`, also known as the ICU "root" locale. This means the result is consistent regardless of the current user's locale and language preferences. + /// + /// Converting from camel case to snake case: + /// 1. Splits words at the boundary of lower-case to upper-case + /// 2. Inserts `_` between words + /// 3. Lowercases the entire string + /// 4. Preserves starting and ending `_`. + /// + /// For example, `oneTwoThree` becomes `one_two_three`. `_oneTwoThree_` becomes `_one_two_three_`. + /// + /// - Note: Using a key encoding strategy has a nominal performance cost, as each string key has to be converted. + case convertToSnakeCase + + /// Provide a custom conversion to the key in the encoded Dictionary from the keys specified by the encoded types. + /// The full path to the current encoding position is provided for context (in case you need to locate this key within the payload). The returned key is used in place of the last component in the coding path before encoding. + /// If the result of the conversion is a duplicate key, then only one value will be present in the result. + case custom((_ codingPath: [CodingKey]) -> CodingKey) + + internal static func _convertToSnakeCase(_ stringKey: String) -> String { + guard stringKey.count > 0 else { return stringKey } + + var words : [Range] = [] + // The general idea of this algorithm is to split words on transition from lower to upper case, then on transition of >1 upper case characters to lowercase + // + // myProperty -> my_property + // myURLProperty -> my_url_property + // + // We assume, per Swift naming conventions, that the first character of the key is lowercase. + var wordStart = stringKey.startIndex + var searchRange = stringKey.index(after: wordStart)..1 capital letters. Turn those into a word, stopping at the capital before the lower case character. + let beforeLowerIndex = stringKey.index(before: lowerCaseRange.lowerBound) + words.append(upperCaseRange.lowerBound..(_ value: T) throws -> NSDictionary { + let encoder = _DictionaryEncoder(options: self.options) + + guard let topLevel = try encoder.box_(value) else { + throw EncodingError.invalidValue(value, EncodingError.Context(codingPath: [], debugDescription: "Top-level \(T.self) did not encode any values.")) + } + + if topLevel is NSNull { + throw EncodingError.invalidValue(value, EncodingError.Context(codingPath: [], debugDescription: "Top-level \(T.self) encoded as null Dictionary fragment.")) + } else if topLevel is NSNumber { + throw EncodingError.invalidValue(value, EncodingError.Context(codingPath: [], debugDescription: "Top-level \(T.self) encoded as number Dictionary fragment.")) + } else if topLevel is NSString { + throw EncodingError.invalidValue(value, EncodingError.Context(codingPath: [], debugDescription: "Top-level \(T.self) encoded as string Dictionary fragment.")) + } + + return topLevel as! NSDictionary + } + + // MARK: - Encoding Values + /// Encodes the given top-level value and returns its Dictionary representation. + /// + /// - parameter value: The value to encode. + /// - returns: A new `Data` value containing the encoded Dictionary data. + /// - throws: `EncodingError.invalidValue` if a non-conforming floating-point value is encountered during encoding, and the encoding strategy is `.throw`. + /// - throws: An error if any value throws an error during encoding. + open func encode(_ value: T) throws -> [String:Any] { + let encoder = _DictionaryEncoder(options: self.options) + + guard let topLevel = try encoder.box_(value) else { + throw EncodingError.invalidValue(value, EncodingError.Context(codingPath: [], debugDescription: "Top-level \(T.self) did not encode any values.")) + } + + if topLevel is NSNull { + throw EncodingError.invalidValue(value, EncodingError.Context(codingPath: [], debugDescription: "Top-level \(T.self) encoded as null Dictionary fragment.")) + } else if topLevel is NSNumber { + throw EncodingError.invalidValue(value, EncodingError.Context(codingPath: [], debugDescription: "Top-level \(T.self) encoded as number Dictionary fragment.")) + } else if topLevel is NSString { + throw EncodingError.invalidValue(value, EncodingError.Context(codingPath: [], debugDescription: "Top-level \(T.self) encoded as string Dictionary fragment.")) + } + + return topLevel as! [String:Any] + } + +} + +// MARK: - _DictionaryEncoder +fileprivate class _DictionaryEncoder : Encoder { + // MARK: Properties + /// The encoder's storage. + fileprivate var storage: _DictionaryEncodingStorage + + /// Options set on the top-level encoder. + fileprivate let options: DictionaryEncoder._Options + + /// The path to the current point in encoding. + public var codingPath: [CodingKey] + + /// Contextual user-provided information for use during encoding. + public var userInfo: [CodingUserInfoKey : Any] { + return self.options.userInfo + } + + // MARK: - Initialization + /// Initializes `self` with the given top-level encoder options. + fileprivate init(options: DictionaryEncoder._Options, codingPath: [CodingKey] = []) { + self.options = options + self.storage = _DictionaryEncodingStorage() + self.codingPath = codingPath + } + + /// Returns whether a new element can be encoded at this coding path. + /// + /// `true` if an element has not yet been encoded at this coding path; `false` otherwise. + fileprivate var canEncodeNewValue: Bool { + // Every time a new value gets encoded, the key it's encoded for is pushed onto the coding path (even if it's a nil key from an unkeyed container). + // At the same time, every time a container is requested, a new value gets pushed onto the storage stack. + // If there are more values on the storage stack than on the coding path, it means the value is requesting more than one container, which violates the precondition. + // + // This means that anytime something that can request a new container goes onto the stack, we MUST push a key onto the coding path. + // Things which will not request containers do not need to have the coding path extended for them (but it doesn't matter if it is, because they will not reach here). + return self.storage.count == self.codingPath.count + } + + // MARK: - Encoder Methods + public func container(keyedBy: Key.Type) -> KeyedEncodingContainer { + // If an existing keyed container was already requested, return that one. + let topContainer: NSMutableDictionary + if self.canEncodeNewValue { + // We haven't yet pushed a container at this level; do so here. + topContainer = self.storage.pushKeyedContainer() + } else { + guard let container = self.storage.containers.last as? NSMutableDictionary else { + preconditionFailure("Attempt to push new keyed encoding container when already previously encoded at this path.") + } + + topContainer = container + } + + let container = DictionaryCodingKeyedEncodingContainer(referencing: self, codingPath: self.codingPath, wrapping: topContainer) + return KeyedEncodingContainer(container) + } + + public func unkeyedContainer() -> UnkeyedEncodingContainer { + // If an existing unkeyed container was already requested, return that one. + let topContainer: NSMutableArray + if self.canEncodeNewValue { + // We haven't yet pushed a container at this level; do so here. + topContainer = self.storage.pushUnkeyedContainer() + } else { + guard let container = self.storage.containers.last as? NSMutableArray else { + preconditionFailure("Attempt to push new unkeyed encoding container when already previously encoded at this path.") + } + + topContainer = container + } + + return _DictionaryUnkeyedEncodingContainer(referencing: self, codingPath: self.codingPath, wrapping: topContainer) + } + + public func singleValueContainer() -> SingleValueEncodingContainer { + return self + } +} + +// MARK: - Encoding Storage and Containers +fileprivate struct _DictionaryEncodingStorage { + // MARK: Properties + /// The container stack. + /// Elements may be any one of the Dictionary types (NSNull, NSNumber, NSString, NSArray, NSDictionary). + private(set) fileprivate var containers: [NSObject] = [] + + // MARK: - Initialization + /// Initializes `self` with no containers. + fileprivate init() {} + + // MARK: - Modifying the Stack + fileprivate var count: Int { + return self.containers.count + } + + fileprivate mutating func pushKeyedContainer() -> NSMutableDictionary { + let dictionary = NSMutableDictionary() + self.containers.append(dictionary) + return dictionary + } + + fileprivate mutating func pushUnkeyedContainer() -> NSMutableArray { + let array = NSMutableArray() + self.containers.append(array) + return array + } + + fileprivate mutating func push(container: NSObject) { + self.containers.append(container) + } + + fileprivate mutating func popContainer() -> NSObject { + precondition(self.containers.count > 0, "Empty container stack.") + return self.containers.popLast()! + } +} + +// MARK: - Encoding Containers +fileprivate struct DictionaryCodingKeyedEncodingContainer : KeyedEncodingContainerProtocol { + typealias Key = K + + // MARK: Properties + /// A reference to the encoder we're writing to. + private let encoder: _DictionaryEncoder + + /// A reference to the container we're writing to. + private let container: NSMutableDictionary + + /// The path of coding keys taken to get to this point in encoding. + private(set) public var codingPath: [CodingKey] + + // MARK: - Initialization + /// Initializes `self` with the given references. + fileprivate init(referencing encoder: _DictionaryEncoder, codingPath: [CodingKey], wrapping container: NSMutableDictionary) { + self.encoder = encoder + self.codingPath = codingPath + self.container = container + } + + // MARK: - Coding Path Operations + private func _converted(_ key: CodingKey) -> CodingKey { + switch encoder.options.keyEncodingStrategy { + case .useDefaultKeys: + return key + case .convertToSnakeCase: + let newKeyString = DictionaryEncoder.KeyEncodingStrategy._convertToSnakeCase(key.stringValue) + return DictionaryCodingKey(stringValue: newKeyString, intValue: key.intValue) + case .custom(let converter): + return converter(codingPath + [key]) + } + } + + // MARK: - KeyedEncodingContainerProtocol Methods + public mutating func encodeNil(forKey key: Key) throws { + self.container[_converted(key).stringValue] = NSNull() + } + public mutating func encode(_ value: Bool, forKey key: Key) throws { + self.container[_converted(key).stringValue] = self.encoder.box(value) + } + public mutating func encode(_ value: Int, forKey key: Key) throws { + self.container[_converted(key).stringValue] = self.encoder.box(value) + } + public mutating func encode(_ value: Int8, forKey key: Key) throws { + self.container[_converted(key).stringValue] = self.encoder.box(value) + } + public mutating func encode(_ value: Int16, forKey key: Key) throws { + self.container[_converted(key).stringValue] = self.encoder.box(value) + } + public mutating func encode(_ value: Int32, forKey key: Key) throws { + self.container[_converted(key).stringValue] = self.encoder.box(value) + } + public mutating func encode(_ value: Int64, forKey key: Key) throws { + self.container[_converted(key).stringValue] = self.encoder.box(value) + } + public mutating func encode(_ value: UInt, forKey key: Key) throws { + self.container[_converted(key).stringValue] = self.encoder.box(value) + } + public mutating func encode(_ value: UInt8, forKey key: Key) throws { + self.container[_converted(key).stringValue] = self.encoder.box(value) + } + public mutating func encode(_ value: UInt16, forKey key: Key) throws { + self.container[_converted(key).stringValue] = self.encoder.box(value) + } + public mutating func encode(_ value: UInt32, forKey key: Key) throws { + self.container[_converted(key).stringValue] = self.encoder.box(value) + } + public mutating func encode(_ value: UInt64, forKey key: Key) throws { + self.container[_converted(key).stringValue] = self.encoder.box(value) + } + public mutating func encode(_ value: String, forKey key: Key) throws { + self.container[_converted(key).stringValue] = self.encoder.box(value) + } + + public mutating func encode(_ value: Float, forKey key: Key) throws { + // Since the float may be invalid and throw, the coding path needs to contain this key. + self.encoder.codingPath.append(key) + defer { self.encoder.codingPath.removeLast() } + self.container[_converted(key).stringValue] = try self.encoder.box(value) + } + + public mutating func encode(_ value: Double, forKey key: Key) throws { + // Since the double may be invalid and throw, the coding path needs to contain this key. + self.encoder.codingPath.append(key) + defer { self.encoder.codingPath.removeLast() } + self.container[_converted(key).stringValue] = try self.encoder.box(value) + } + + public mutating func encode(_ value: T, forKey key: Key) throws { + self.encoder.codingPath.append(key) + defer { self.encoder.codingPath.removeLast() } + self.container[_converted(key).stringValue] = try self.encoder.box(value) + } + + public mutating func nestedContainer(keyedBy keyType: NestedKey.Type, forKey key: Key) -> KeyedEncodingContainer { + let dictionary = NSMutableDictionary() + self.container[_converted(key).stringValue] = dictionary + + self.codingPath.append(key) + defer { self.codingPath.removeLast() } + + let container = DictionaryCodingKeyedEncodingContainer(referencing: self.encoder, codingPath: self.codingPath, wrapping: dictionary) + return KeyedEncodingContainer(container) + } + + public mutating func nestedUnkeyedContainer(forKey key: Key) -> UnkeyedEncodingContainer { + let array = NSMutableArray() + self.container[_converted(key).stringValue] = array + + self.codingPath.append(key) + defer { self.codingPath.removeLast() } + return _DictionaryUnkeyedEncodingContainer(referencing: self.encoder, codingPath: self.codingPath, wrapping: array) + } + + public mutating func superEncoder() -> Encoder { + return _DictionaryReferencingEncoder(referencing: self.encoder, key: DictionaryCodingKey.super, convertedKey: _converted(DictionaryCodingKey.super), wrapping: self.container) + } + + public mutating func superEncoder(forKey key: Key) -> Encoder { + return _DictionaryReferencingEncoder(referencing: self.encoder, key: key, convertedKey: _converted(key), wrapping: self.container) + } +} + +fileprivate struct _DictionaryUnkeyedEncodingContainer : UnkeyedEncodingContainer { + // MARK: Properties + /// A reference to the encoder we're writing to. + private let encoder: _DictionaryEncoder + + /// A reference to the container we're writing to. + private let container: NSMutableArray + + /// The path of coding keys taken to get to this point in encoding. + private(set) public var codingPath: [CodingKey] + + /// The number of elements encoded into the container. + public var count: Int { + return self.container.count + } + + // MARK: - Initialization + /// Initializes `self` with the given references. + fileprivate init(referencing encoder: _DictionaryEncoder, codingPath: [CodingKey], wrapping container: NSMutableArray) { + self.encoder = encoder + self.codingPath = codingPath + self.container = container + } + + // MARK: - UnkeyedEncodingContainer Methods + public mutating func encodeNil() throws { self.container.add(NSNull()) } + public mutating func encode(_ value: Bool) throws { self.container.add(self.encoder.box(value)) } + public mutating func encode(_ value: Int) throws { self.container.add(self.encoder.box(value)) } + public mutating func encode(_ value: Int8) throws { self.container.add(self.encoder.box(value)) } + public mutating func encode(_ value: Int16) throws { self.container.add(self.encoder.box(value)) } + public mutating func encode(_ value: Int32) throws { self.container.add(self.encoder.box(value)) } + public mutating func encode(_ value: Int64) throws { self.container.add(self.encoder.box(value)) } + public mutating func encode(_ value: UInt) throws { self.container.add(self.encoder.box(value)) } + public mutating func encode(_ value: UInt8) throws { self.container.add(self.encoder.box(value)) } + public mutating func encode(_ value: UInt16) throws { self.container.add(self.encoder.box(value)) } + public mutating func encode(_ value: UInt32) throws { self.container.add(self.encoder.box(value)) } + public mutating func encode(_ value: UInt64) throws { self.container.add(self.encoder.box(value)) } + public mutating func encode(_ value: String) throws { self.container.add(self.encoder.box(value)) } + + public mutating func encode(_ value: Float) throws { + // Since the float may be invalid and throw, the coding path needs to contain this key. + self.encoder.codingPath.append(DictionaryCodingKey(index: self.count)) + defer { self.encoder.codingPath.removeLast() } + self.container.add(try self.encoder.box(value)) + } + + public mutating func encode(_ value: Double) throws { + // Since the double may be invalid and throw, the coding path needs to contain this key. + self.encoder.codingPath.append(DictionaryCodingKey(index: self.count)) + defer { self.encoder.codingPath.removeLast() } + self.container.add(try self.encoder.box(value)) + } + + public mutating func encode(_ value: T) throws { + self.encoder.codingPath.append(DictionaryCodingKey(index: self.count)) + defer { self.encoder.codingPath.removeLast() } + self.container.add(try self.encoder.box(value)) + } + + public mutating func nestedContainer(keyedBy keyType: NestedKey.Type) -> KeyedEncodingContainer { + self.codingPath.append(DictionaryCodingKey(index: self.count)) + defer { self.codingPath.removeLast() } + + let dictionary = NSMutableDictionary() + self.container.add(dictionary) + + let container = DictionaryCodingKeyedEncodingContainer(referencing: self.encoder, codingPath: self.codingPath, wrapping: dictionary) + return KeyedEncodingContainer(container) + } + + public mutating func nestedUnkeyedContainer() -> UnkeyedEncodingContainer { + self.codingPath.append(DictionaryCodingKey(index: self.count)) + defer { self.codingPath.removeLast() } + + let array = NSMutableArray() + self.container.add(array) + return _DictionaryUnkeyedEncodingContainer(referencing: self.encoder, codingPath: self.codingPath, wrapping: array) + } + + public mutating func superEncoder() -> Encoder { + return _DictionaryReferencingEncoder(referencing: self.encoder, at: self.container.count, wrapping: self.container) + } +} + +extension _DictionaryEncoder : SingleValueEncodingContainer { + // MARK: - SingleValueEncodingContainer Methods + fileprivate func assertCanEncodeNewValue() { + precondition(self.canEncodeNewValue, "Attempt to encode value through single value container when previously value already encoded.") + } + + public func encodeNil() throws { + assertCanEncodeNewValue() + self.storage.push(container: NSNull()) + } + + public func encode(_ value: Bool) throws { + assertCanEncodeNewValue() + self.storage.push(container: self.box(value)) + } + + public func encode(_ value: Int) throws { + assertCanEncodeNewValue() + self.storage.push(container: self.box(value)) + } + + public func encode(_ value: Int8) throws { + assertCanEncodeNewValue() + self.storage.push(container: self.box(value)) + } + + public func encode(_ value: Int16) throws { + assertCanEncodeNewValue() + self.storage.push(container: self.box(value)) + } + + public func encode(_ value: Int32) throws { + assertCanEncodeNewValue() + self.storage.push(container: self.box(value)) + } + + public func encode(_ value: Int64) throws { + assertCanEncodeNewValue() + self.storage.push(container: self.box(value)) + } + + public func encode(_ value: UInt) throws { + assertCanEncodeNewValue() + self.storage.push(container: self.box(value)) + } + + public func encode(_ value: UInt8) throws { + assertCanEncodeNewValue() + self.storage.push(container: self.box(value)) + } + + public func encode(_ value: UInt16) throws { + assertCanEncodeNewValue() + self.storage.push(container: self.box(value)) + } + + public func encode(_ value: UInt32) throws { + assertCanEncodeNewValue() + self.storage.push(container: self.box(value)) + } + + public func encode(_ value: UInt64) throws { + assertCanEncodeNewValue() + self.storage.push(container: self.box(value)) + } + + public func encode(_ value: String) throws { + assertCanEncodeNewValue() + self.storage.push(container: self.box(value)) + } + + public func encode(_ value: Float) throws { + assertCanEncodeNewValue() + try self.storage.push(container: self.box(value)) + } + + public func encode(_ value: Double) throws { + assertCanEncodeNewValue() + try self.storage.push(container: self.box(value)) + } + + public func encode(_ value: T) throws { + assertCanEncodeNewValue() + try self.storage.push(container: self.box(value)) + } +} + +// MARK: - Concrete Value Representations +extension _DictionaryEncoder { + /// Returns the given value boxed in a container appropriate for pushing onto the container stack. + fileprivate func box(_ value: Bool) -> NSObject { return NSNumber(value: value) } + fileprivate func box(_ value: Int) -> NSObject { return NSNumber(value: value) } + fileprivate func box(_ value: Int8) -> NSObject { return NSNumber(value: value) } + fileprivate func box(_ value: Int16) -> NSObject { return NSNumber(value: value) } + fileprivate func box(_ value: Int32) -> NSObject { return NSNumber(value: value) } + fileprivate func box(_ value: Int64) -> NSObject { return NSNumber(value: value) } + fileprivate func box(_ value: UInt) -> NSObject { return NSNumber(value: value) } + fileprivate func box(_ value: UInt8) -> NSObject { return NSNumber(value: value) } + fileprivate func box(_ value: UInt16) -> NSObject { return NSNumber(value: value) } + fileprivate func box(_ value: UInt32) -> NSObject { return NSNumber(value: value) } + fileprivate func box(_ value: UInt64) -> NSObject { return NSNumber(value: value) } + fileprivate func box(_ value: String) -> NSObject { return NSString(string: value) } + + fileprivate func box(_ float: Float) throws -> NSObject { + guard !float.isInfinite && !float.isNaN else { + guard case let .convertToString(positiveInfinity: posInfString, + negativeInfinity: negInfString, + nan: nanString) = self.options.nonConformingFloatEncodingStrategy else { + throw EncodingError._invalidFloatingPointValue(float, at: codingPath) + } + + if float == Float.infinity { + return NSString(string: posInfString) + } else if float == -Float.infinity { + return NSString(string: negInfString) + } else { + return NSString(string: nanString) + } + } + + return NSNumber(value: float) + } + + fileprivate func box(_ double: Double) throws -> NSObject { + guard !double.isInfinite && !double.isNaN else { + guard case let .convertToString(positiveInfinity: posInfString, + negativeInfinity: negInfString, + nan: nanString) = self.options.nonConformingFloatEncodingStrategy else { + throw EncodingError._invalidFloatingPointValue(double, at: codingPath) + } + + if double == Double.infinity { + return NSString(string: posInfString) + } else if double == -Double.infinity { + return NSString(string: negInfString) + } else { + return NSString(string: nanString) + } + } + + return NSNumber(value: double) + } + + fileprivate func box(_ date: Date) throws -> NSObject { + switch self.options.dateEncodingStrategy { + case .deferredToDate: + // Must be called with a surrounding with(pushedKey:) call. + // Dates encode as single-value objects; this can't both throw and push a container, so no need to catch the error. + try date.encode(to: self) + return self.storage.popContainer() + + case .secondsSince1970: + return NSNumber(value: date.timeIntervalSince1970) + + case .millisecondsSince1970: + return NSNumber(value: 1000.0 * date.timeIntervalSince1970) + + case .iso8601: + if #available(OSX 10.12, iOS 10.0, watchOS 3.0, tvOS 10.0, *) { + return NSString(string: _iso8601Formatter.string(from: date)) + } else { + fatalError("ISO8601DateFormatter is unavailable on this platform.") + } + + case .formatted(let formatter): + return NSString(string: formatter.string(from: date)) + + case .custom(let closure): + let depth = self.storage.count + do { + try closure(date, self) + } catch { + // If the value pushed a container before throwing, pop it back off to restore state. + if self.storage.count > depth { + let _ = self.storage.popContainer() + } + + throw error + } + + guard self.storage.count > depth else { + // The closure didn't encode anything. Return the default keyed container. + return NSDictionary() + } + + // We can pop because the closure encoded something. + return self.storage.popContainer() + } + } + + fileprivate func box(_ data: Data) throws -> NSObject { + switch self.options.dataEncodingStrategy { + case .deferredToData: + // Must be called with a surrounding with(pushedKey:) call. + let depth = self.storage.count + do { + try data.encode(to: self) + } catch { + // If the value pushed a container before throwing, pop it back off to restore state. + // This shouldn't be possible for Data (which encodes as an array of bytes), but it can't hurt to catch a failure. + if self.storage.count > depth { + let _ = self.storage.popContainer() + } + + throw error + } + + return self.storage.popContainer() + + case .base64: + return NSString(string: data.base64EncodedString()) + + case .custom(let closure): + let depth = self.storage.count + do { + try closure(data, self) + } catch { + // If the value pushed a container before throwing, pop it back off to restore state. + if self.storage.count > depth { + let _ = self.storage.popContainer() + } + + throw error + } + + guard self.storage.count > depth else { + // The closure didn't encode anything. Return the default keyed container. + return NSDictionary() + } + + // We can pop because the closure encoded something. + return self.storage.popContainer() + } + } + + fileprivate func box(_ value: T) throws -> NSObject { + return try self.box_(value) ?? NSDictionary() + } + + // This method is called "box_" instead of "box" to disambiguate it from the overloads. Because the return type here is different from all of the "box" overloads (and is more general), any "box" calls in here would call back into "box" recursively instead of calling the appropriate overload, which is not what we want. + fileprivate func box_(_ value: T) throws -> NSObject? { + if T.self == Date.self || T.self == NSDate.self { + // Respect Date encoding strategy + return try self.box((value as! Date)) + } else if T.self == Data.self || T.self == NSData.self { + // Respect Data encoding strategy + return try self.box((value as! Data)) + } else if T.self == URL.self || T.self == NSURL.self { + // Encode URLs as single strings. + return self.box((value as! URL).absoluteString) + } else if T.self == Decimal.self || T.self == NSDecimalNumber.self { + // DictionarySerialization can natively handle NSDecimalNumber. + return (value as! NSDecimalNumber) + } + + // The value should request a container from the _DictionaryEncoder. + let depth = self.storage.count + do { + try value.encode(to: self) + } catch { + // If the value pushed a container before throwing, pop it back off to restore state. + if self.storage.count > depth { + let _ = self.storage.popContainer() + } + + throw error + } + + // The top container should be a new container. + guard self.storage.count > depth else { + return nil + } + + return self.storage.popContainer() + } +} + +// MARK: - _DictionaryReferencingEncoder +/// _DictionaryReferencingEncoder is a special subclass of _DictionaryEncoder which has its own storage, but references the contents of a different encoder. +/// It's used in superEncoder(), which returns a new encoder for encoding a superclass -- the lifetime of the encoder should not escape the scope it's created in, but it doesn't necessarily know when it's done being used (to write to the original container). +fileprivate class _DictionaryReferencingEncoder : _DictionaryEncoder { + // MARK: Reference types. + /// The type of container we're referencing. + private enum Reference { + /// Referencing a specific index in an array container. + case array(NSMutableArray, Int) + + /// Referencing a specific key in a dictionary container. + case dictionary(NSMutableDictionary, String) + } + + // MARK: - Properties + /// The encoder we're referencing. + fileprivate let encoder: _DictionaryEncoder + + /// The container reference itself. + private let reference: Reference + + // MARK: - Initialization + /// Initializes `self` by referencing the given array container in the given encoder. + fileprivate init(referencing encoder: _DictionaryEncoder, at index: Int, wrapping array: NSMutableArray) { + self.encoder = encoder + self.reference = .array(array, index) + super.init(options: encoder.options, codingPath: encoder.codingPath) + + self.codingPath.append(DictionaryCodingKey(index: index)) + } + + /// Initializes `self` by referencing the given dictionary container in the given encoder. + fileprivate init(referencing encoder: _DictionaryEncoder, + key: CodingKey, convertedKey: CodingKey, wrapping dictionary: NSMutableDictionary) { + self.encoder = encoder + self.reference = .dictionary(dictionary, convertedKey.stringValue) + super.init(options: encoder.options, codingPath: encoder.codingPath) + + self.codingPath.append(key) + } + + // MARK: - Coding Path Operations + fileprivate override var canEncodeNewValue: Bool { + // With a regular encoder, the storage and coding path grow together. + // A referencing encoder, however, inherits its parents coding path, as well as the key it was created for. + // We have to take this into account. + return self.storage.count == self.codingPath.count - self.encoder.codingPath.count - 1 + } + + // MARK: - Deinitialization + // Finalizes `self` by writing the contents of our storage to the referenced encoder's storage. + deinit { + let value: Any + switch self.storage.count { + case 0: value = NSDictionary() + case 1: value = self.storage.popContainer() + default: fatalError("Referencing encoder deallocated with multiple containers on stack.") + } + + switch self.reference { + case .array(let array, let index): + array.insert(value, at: index) + + case .dictionary(let dictionary, let key): + dictionary[NSString(string: key)] = value + } + } +} + + +#if canImport(Combine) +import Combine + +extension DictionaryEncoder: TopLevelEncoder { + public typealias Output = [String: Any] +} +#endif \ No newline at end of file diff --git a/ios/Helpers/DictionaryErrors.swift b/ios/Helpers/DictionaryErrors.swift new file mode 100644 index 0000000..2445561 --- /dev/null +++ b/ios/Helpers/DictionaryErrors.swift @@ -0,0 +1,82 @@ +//===----------------------------------------------------------------------===// +// +// This source file is largely a copy of code from Swift.org open source project's +// files JSONEncoder.swift and Codeable.swift. +// +// Unfortunately those files do not expose the internal _JSONEncoder and +// _JSONDecoder classes, which are in fact dictionary encoder/decoders and +// precisely what we want... +// +// The original code is copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors +// Licensed under Apache License v2.0 with Runtime Library Exception +// +// See https://swift.org/LICENSE.txt for license information +// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors +// +// Modifications and additional code here is copyright (c) 2018 Sam Deane, and +// is licensed under the same terms. +// +//===----------------------------------------------------------------------===// + +import Foundation + + +//===----------------------------------------------------------------------===// +// Error Utilities +//===----------------------------------------------------------------------===// + +internal extension EncodingError { + /// Returns a `.invalidValue` error describing the given invalid floating-point value. + /// + /// + /// - parameter value: The value that was invalid to encode. + /// - parameter path: The path of `CodingKey`s taken to encode this value. + /// - returns: An `EncodingError` with the appropriate path and debug description. + static func _invalidFloatingPointValue(_ value: T, at codingPath: [CodingKey]) -> EncodingError { + let valueDescription: String + if value == T.infinity { + valueDescription = "\(T.self).infinity" + } else if value == -T.infinity { + valueDescription = "-\(T.self).infinity" + } else { + valueDescription = "\(T.self).nan" + } + + let debugDescription = "Unable to encode \(valueDescription) directly in Dictionary. Use DictionaryEncoder.NonConformingFloatEncodingStrategy.convertToString to specify how the value should be encoded." + return .invalidValue(value, EncodingError.Context(codingPath: codingPath, debugDescription: debugDescription)) + } +} + +internal extension DecodingError { + /// Returns a `.typeMismatch` error describing the expected type. + /// + /// - parameter path: The path of `CodingKey`s taken to decode a value of this type. + /// - parameter expectation: The type expected to be encountered. + /// - parameter reality: The value that was encountered instead of the expected type. + /// - returns: A `DecodingError` with the appropriate path and debug description. + static func _typeMismatch(at path: [CodingKey], expectation: Any.Type, reality: Any) -> DecodingError { + let description = "Expected to decode \(expectation) but found \(_typeDescription(of: reality)) instead." + return .typeMismatch(expectation, Context(codingPath: path, debugDescription: description)) + } + + /// Returns a description of the type of `value` appropriate for an error message. + /// + /// - parameter value: The value whose type to describe. + /// - returns: A string describing `value`. + /// - precondition: `value` is one of the types below. + static func _typeDescription(of value: Any) -> String { + if value is NSNull { + return "a null value" + } else if value is NSNumber /* FIXME: If swift-corelibs-foundation isn't updated to use NSNumber, this check will be necessary: || value is Int || value is Double */ { + return "a number" + } else if value is String { + return "a string/data" + } else if value is [Any] { + return "an array" + } else if value is [String : Any] { + return "a dictionary" + } else { + return "\(type(of: value))" + } + } +} \ No newline at end of file