How to use _PlistReferencingEncoder class

...227        defer { self.codingPath.removeLast() }228        return _PlistUnkeyedEncodingContainer(referencing: self.encoder, codingPath: self.codingPath, wrapping: array)229    }230    public mutating func superEncoder() -> Encoder {231        return _PlistReferencingEncoder(referencing: self.encoder, at: _PlistKey.super, wrapping: self.container)232    }233    public mutating func superEncoder(forKey key: Key) -> Encoder {234        return _PlistReferencingEncoder(referencing: self.encoder, at: key, wrapping: self.container)235    }236}237fileprivate struct _PlistUnkeyedEncodingContainer : UnkeyedEncodingContainer {238    // MARK: Properties239    /// A reference to the encoder we're writing to.240    private let encoder: _PlistEncoder241    /// A reference to the container we're writing to.242    private let container: NSMutableArray243    /// The path of coding keys taken to get to this point in encoding.244    private(set) public var codingPath: [CodingKey]245    /// The number of elements encoded into the container.246    public var count: Int {247        return self.container.count248    }249    // MARK: - Initialization250    /// Initializes `self` with the given references.251    fileprivate init(referencing encoder: _PlistEncoder, codingPath: [CodingKey], wrapping container: NSMutableArray) {252        self.encoder = encoder253        self.codingPath = codingPath254        self.container = container255    }256    // MARK: - UnkeyedEncodingContainer Methods257    public mutating func encodeNil()             throws { self.container.add(_plistNullNSString) }258    public mutating func encode(_ value: Bool)   throws { self.container.add(self.encoder.box(value)) }259    public mutating func encode(_ value: Int)    throws { self.container.add(self.encoder.box(value)) }260    public mutating func encode(_ value: Int8)   throws { self.container.add(self.encoder.box(value)) }261    public mutating func encode(_ value: Int16)  throws { self.container.add(self.encoder.box(value)) }262    public mutating func encode(_ value: Int32)  throws { self.container.add(self.encoder.box(value)) }263    public mutating func encode(_ value: Int64)  throws { self.container.add(self.encoder.box(value)) }264    public mutating func encode(_ value: UInt)   throws { self.container.add(self.encoder.box(value)) }265    public mutating func encode(_ value: UInt8)  throws { self.container.add(self.encoder.box(value)) }266    public mutating func encode(_ value: UInt16) throws { self.container.add(self.encoder.box(value)) }267    public mutating func encode(_ value: UInt32) throws { self.container.add(self.encoder.box(value)) }268    public mutating func encode(_ value: UInt64) throws { self.container.add(self.encoder.box(value)) }269    public mutating func encode(_ value: Float)  throws { self.container.add(self.encoder.box(value)) }270    public mutating func encode(_ value: Double) throws { self.container.add(self.encoder.box(value)) }271    public mutating func encode(_ value: String) throws { self.container.add(self.encoder.box(value)) }272    public mutating func encode<T : Encodable>(_ value: T) throws {273        self.encoder.codingPath.append(_PlistKey(index: self.count))274        defer { self.encoder.codingPath.removeLast() }275        self.container.add(try self.encoder.box(value))276    }277    public mutating func nestedContainer<NestedKey>(keyedBy keyType: NestedKey.Type) -> KeyedEncodingContainer<NestedKey> {278        self.codingPath.append(_PlistKey(index: self.count))279        defer { self.codingPath.removeLast() }280        let dictionary = NSMutableDictionary()281        self.container.add(dictionary)282        let container = _PlistKeyedEncodingContainer<NestedKey>(referencing: self.encoder, codingPath: self.codingPath, wrapping: dictionary)283        return KeyedEncodingContainer(container)284    }285    public mutating func nestedUnkeyedContainer() -> UnkeyedEncodingContainer {286        self.codingPath.append(_PlistKey(index: self.count))287        defer { self.codingPath.removeLast() }288        let array = NSMutableArray()289        self.container.add(array)290        return _PlistUnkeyedEncodingContainer(referencing: self.encoder, codingPath: self.codingPath, wrapping: array)291    }292    public mutating func superEncoder() -> Encoder {293        return _PlistReferencingEncoder(referencing: self.encoder, at: self.container.count, wrapping: self.container)294    }295}296extension _PlistEncoder : SingleValueEncodingContainer {297    // MARK: - SingleValueEncodingContainer Methods298    private func assertCanEncodeNewValue() {299        precondition(self.canEncodeNewValue, "Attempt to encode value through single value container when previously value already encoded.")300    }301    public func encodeNil() throws {302        assertCanEncodeNewValue()303        self.storage.push(container: _plistNullNSString)304    }305    public func encode(_ value: Bool) throws {306        assertCanEncodeNewValue()307        self.storage.push(container: self.box(value))308    }309    public func encode(_ value: Int) throws {310        assertCanEncodeNewValue()311        self.storage.push(container: self.box(value))312    }313    public func encode(_ value: Int8) throws {314        assertCanEncodeNewValue()315        self.storage.push(container: self.box(value))316    }317    public func encode(_ value: Int16) throws {318        assertCanEncodeNewValue()319        self.storage.push(container: self.box(value))320    }321    public func encode(_ value: Int32) throws {322        assertCanEncodeNewValue()323        self.storage.push(container: self.box(value))324    }325    public func encode(_ value: Int64) throws {326        assertCanEncodeNewValue()327        self.storage.push(container: self.box(value))328    }329    public func encode(_ value: UInt) throws {330        assertCanEncodeNewValue()331        self.storage.push(container: self.box(value))332    }333    public func encode(_ value: UInt8) throws {334        assertCanEncodeNewValue()335        self.storage.push(container: self.box(value))336    }337    public func encode(_ value: UInt16) throws {338        assertCanEncodeNewValue()339        self.storage.push(container: self.box(value))340    }341    public func encode(_ value: UInt32) throws {342        assertCanEncodeNewValue()343        self.storage.push(container: self.box(value))344    }345    public func encode(_ value: UInt64) throws {346        assertCanEncodeNewValue()347        self.storage.push(container: self.box(value))348    }349    public func encode(_ value: String) throws {350        assertCanEncodeNewValue()351        self.storage.push(container: self.box(value))352    }353    public func encode(_ value: Float) throws {354        assertCanEncodeNewValue()355        self.storage.push(container: self.box(value))356    }357    public func encode(_ value: Double) throws {358        assertCanEncodeNewValue()359        self.storage.push(container: self.box(value))360    }361    public func encode<T : Encodable>(_ value: T) throws {362        assertCanEncodeNewValue()363        try self.storage.push(container: self.box(value))364    }365}366// MARK: - Concrete Value Representations367extension _PlistEncoder {368    /// Returns the given value boxed in a container appropriate for pushing onto the container stack.369    fileprivate func box(_ value: Bool)   -> NSObject { return NSNumber(value: value) }370    fileprivate func box(_ value: Int)    -> NSObject { return NSNumber(value: value) }371    fileprivate func box(_ value: Int8)   -> NSObject { return NSNumber(value: value) }372    fileprivate func box(_ value: Int16)  -> NSObject { return NSNumber(value: value) }373    fileprivate func box(_ value: Int32)  -> NSObject { return NSNumber(value: value) }374    fileprivate func box(_ value: Int64)  -> NSObject { return NSNumber(value: value) }375    fileprivate func box(_ value: UInt)   -> NSObject { return NSNumber(value: value) }376    fileprivate func box(_ value: UInt8)  -> NSObject { return NSNumber(value: value) }377    fileprivate func box(_ value: UInt16) -> NSObject { return NSNumber(value: value) }378    fileprivate func box(_ value: UInt32) -> NSObject { return NSNumber(value: value) }379    fileprivate func box(_ value: UInt64) -> NSObject { return NSNumber(value: value) }380    fileprivate func box(_ value: Float)  -> NSObject { return NSNumber(value: value) }381    fileprivate func box(_ value: Double) -> NSObject { return NSNumber(value: value) }382    fileprivate func box(_ value: String) -> NSObject { return NSString(string: value) }383    fileprivate func box<T : Encodable>(_ value: T) throws -> NSObject {384        return try self.box_(value) ?? NSDictionary()385    }386    fileprivate func box_<T : Encodable>(_ value: T) throws -> NSObject? {387        if T.self == Date.self || T.self == NSDate.self {388            // PropertyListSerialization handles NSDate directly.389            return (value as! NSDate)390        } else if T.self == Data.self || T.self == NSData.self {391            // PropertyListSerialization handles NSData directly.392            return (value as! NSData)393        }394        // The value should request a container from the _PlistEncoder.395        let depth = self.storage.count396        do {397            try value.encode(to: self)398        } catch let error {399            // If the value pushed a container before throwing, pop it back off to restore state.400            if self.storage.count > depth {401                let _ = self.storage.popContainer()402            }403            throw error404        }405        // The top container should be a new container.406        guard self.storage.count > depth else {407            return nil408        }409        return self.storage.popContainer()410    }411}412// MARK: - _PlistReferencingEncoder413/// _PlistReferencingEncoder is a special subclass of _PlistEncoder which has its own storage, but references the contents of a different encoder.414/// 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).415fileprivate class _PlistReferencingEncoder : _PlistEncoder {416    // MARK: Reference types.417    /// The type of container we're referencing.418    private enum Reference {419        /// Referencing a specific index in an array container.420        case array(NSMutableArray, Int)421        /// Referencing a specific key in a dictionary container.422        case dictionary(NSMutableDictionary, String)423    }424    // MARK: - Properties425    /// The encoder we're referencing.426    private let encoder: _PlistEncoder427    /// The container reference itself.428    private let reference: Reference429    // MARK: - Initialization...

1import XCTest2import SnapshotTesting3class _PlistReferencingEncoderTests: XCTestCase {4    func test() {5        let data = try! JSONEncoder().encode(Example())6        let plist = try! PropertyListSerialization.propertyList(from: data, options: [], format: nil)7        let encoder = _PlistReferencingEncoder()8        let encoded = try! encoder.encode(plist)9        assertSnapshot(matching: encoded, as: .lines)10    }11}12struct Example: Encodable {13}14import XCTest15import SnapshotTesting16class _PlistReferencingEncoderTests: XCTestCase {17    func test() {18        let data = try! JSONEncoder().encode(Example())19        let plist = try! PropertyListSerialization.propertyList(from: data, options: [], format: nil)20        let encoder = _PlistReferencingEncoder()21        let encoded = try! encoder.encode(plist)22        assertSnapshot(matching: encoded, as: .lines)23    }24}25struct Example: Encodable {26}27import XCTest28import SnapshotTesting29class _PlistReferencingEncoderTests: XCTestCase {30    func test() {31        let data = try! JSONEncoder().encode(Example())32        let plist = try! PropertyListSerialization.propertyList(from: data, options: [], format: nil)33        let encoder = _PlistReferencingEncoder()34        let encoded = try! encoder.encode(plist)35        assertSnapshot(matching: encoded, as: .lines)36    }37}38struct Example: Encodable {39}40import XCTest41import SnapshotTesting42class _PlistReferencingEncoderTests: XCTestCase {43    func test() {44        let data = try! JSONEncoder().encode(Example())45        let plist = try! PropertyListSerialization.propertyList(from: data, options: [], format: nil)46        let encoder = _PlistReferencingEncoder()

1import SnapshotTesting2import XCTest3class TestClass: XCTestCase {4    func testExample() {5        let encoder = _PlistReferencingEncoder()6        let data = try! encoder.encode(value)7        let string = String(data: data, encoding: .utf8)!8        print(string)9    }10}11import SnapshotTesting12import XCTest13class TestClass: XCTestCase {14    func testExample() {15        let encoder = _XMLEncoder()16        let data = try! encoder.encode(value)17        let string = String(data: data, encoding: .utf8)!18        print(string)19    }20}21import SnapshotTesting22import XCTest23class TestClass: XCTestCase {24    func testExample() {25        let encoder = _JSONEncoder()26        let data = try! encoder.encode(value)27        let string = String(data: data, encoding: .utf8)!28        print(string)29    }30}31import SnapshotTesting32import XCTest33class TestClass: XCTestCase {34    func testExample() {35        let encoder = _PropertyListEncoder()36        let data = try! encoder.encode(value)37        let string = String(data: data, encoding: .utf8)!38        print(string)39    }40}41import SnapshotTesting42import XCTest43class TestClass: XCTestCase {44    func testExample() {

1import XCTest2import SnapshotTesting3class SnapshotTests: XCTestCase {4    func test() {5        assertSnapshot(matching: value, as: .json)6    }7}8import XCTest9import SnapshotTesting10class SnapshotTests: XCTestCase {11    func test() {12        assertSnapshot(matching: value, as: .json)13    }14}15import XCTest16import SnapshotTesting17class SnapshotTests: XCTestCase {18    func test() {19        assertSnapshot(matching: value, as: .json)20    }21}22/Users/username/Downloads/Swift-snapshot-testing/1.swift:8: error: -[SnapshotTests.SnapshotTests test] : failed - Snapshot comparison failed: Optional(Error Domain=NSCocoaErrorDomain Code=3840 "JSON text did not start with array or object and option to allow fragments not set." UserInfo={NSDebugDescription=JSON text did not start with array or object and option to allow fragments not set.})23	 Executed 1 test, with 1 failure (0 unexpected) in 0.001 (0.001) seconds

1let encoder = _PlistReferencingEncoder()2let result = try encoder.encode(["a": "b"])3let plist = try PropertyListSerialization.propertyList(from: result, options: [], format: nil)4print(plist)5let encoder = PropertyListEncoder()6let result = try encoder.encode(["a": "b"])7let plist = try PropertyListSerialization.propertyList(from: result, options: [], format: nil)8print(plist)9let encoder = _PlistReferencingEncoder()10let result = try encoder.encode(["a": "b"])11let plist = try PropertyListSerialization.propertyList(from: result, options: [], format: nil)12print(plist)13let encoder = PropertyListEncoder()14let result = try encoder.encode(["a": "b"])15let plist = try PropertyListSerialization.propertyList(from: result, options: [], format: nil)16print(plist)17let encoder = _PlistReferencingEncoder()18let result = try encoder.encode(["a": "b"])19let plist = try PropertyListSerialization.propertyList(from: result, options: [], format: nil)20print(plist)21let encoder = PropertyListEncoder()22let result = try encoder.encode(["a": "b"])23let plist = try PropertyListSerialization.propertyList(from: result, options: [], format: nil)24print(plist)25let encoder = _PlistReferencingEncoder()26let result = try encoder.encode(["a": "b"])

1import Foundation2import XCTest3import SnapshotTesting4import _SwiftSnapshotTesting5class SwiftSnapshotTestingTests: XCTestCase {6    func testPlistEncoding() {7        let encoder = _PlistReferencingEncoder()8        let plist = try! encoder.encode(["hello": "world"])9        assertSnapshot(matching: plist, as: .plist)10    }11}12import Foundation13import XCTest14import SnapshotTesting15import _SwiftSnapshotTesting16class SwiftSnapshotTestingTests: XCTestCase {17    func testPlistEncoding() {18        let encoder = _PlistReferencingEncoder()19        let plist = try! encoder.encode(["hello": "world"])20        assertSnapshot(matching: plist, as: .plist)21    }22}23import Foundation24import XCTest25import SnapshotTesting26import _SwiftSnapshotTesting27class SwiftSnapshotTestingTests: XCTestCase {28    func testPlistEncoding() {29        let encoder = _PlistReferencingEncoder()30        let plist = try! encoder.encode(["hello": "world"])31        assertSnapshot(matching: plist, as: .plist)32    }33}34import Foundation35import XCTest36import SnapshotTesting37import _SwiftSnapshotTesting38class SwiftSnapshotTestingTests: XCTestCase {39    func testPlistEncoding() {40        let encoder = _PlistReferencingEncoder()41        let plist = try! encoder.encode(["hello": "world"])42        assertSnapshot(matching: plist, as: .plist)43    }44}45import Foundation46import XCTest47import SnapshotTesting48import _SwiftSnapshotTesting49class SwiftSnapshotTestingTests: XCTestCase {50    func testPlistEncoding() {51        let encoder = _PlistReferencingEncoder()52        let plist = try! encoder.encode(["hello": "world"])53        assertSnapshot(matching: plist, as: .plist)54    }55}56import Foundation57import XCTest58import SnapshotTesting59import _SwiftSnapshot

1let encoder = _PlistReferencingEncoder()2let plist = try! encoder.encode(StructToEncode())3let data = try! PropertyListSerialization.data(fromPropertyList: plist, format: .xml, options: 0)4try! data.write(to: URL(fileURLWithPath: "/path/to/file.plist"))5let decoder = _PlistReferencingDecoder()6let plist = try! PropertyListSerialization.propertyList(from: data, options: [], format: nil)7let decodedStruct = try! decoder.decode(StructToDecode.self, from: plist)8let data = try! PropertyListSerialization.data(fromPropertyList: plist, format: .binary, options: 0)