├── .editorconfig ├── NonEmpty.playground ├── Contents.swift └── contents.xcplayground ├── .swiftpm └── xcode │ └── package.xcworkspace │ └── contents.xcworkspacedata ├── Package.swift ├── Makefile ├── Sources └── NonEmpty │ ├── NonEmpty+ExpressibleByArrayLiteral.swift │ ├── NonEmpty+ExpressibleByDictionaryLiteral.swift │ ├── NonEmpty+RangeReplaceableCollection.swift │ ├── NonEmpty+Dictionary.swift │ ├── NonEmpty+String.swift │ ├── NonEmpty+SetAlgebra.swift │ └── NonEmpty.swift ├── .github ├── workflows │ ├── format.yml │ └── ci.yml └── CODE_OF_CONDUCT.md ├── LICENSE ├── .gitignore ├── README.md └── Tests └── NonEmptyTests └── NonEmptyTests.swift /.editorconfig: -------------------------------------------------------------------------------- 1 | # editorconfig.org 2 | 3 | root = true 4 | 5 | [*] 6 | indent_style = space 7 | indent_size = 2 8 | trim_trailing_whitespace = true 9 | insert_final_newline = true 10 | -------------------------------------------------------------------------------- /NonEmpty.playground/Contents.swift: -------------------------------------------------------------------------------- 1 | import NonEmpty 2 | 3 | let xs = NonEmptyArray(42, 1, 3, 2) 4 | 5 | let str: NonEmptyString = xs 6 | .sorted() 7 | .map { NonEmptyString($0)! } 8 | .joined(separator: ",") 9 | -------------------------------------------------------------------------------- /.swiftpm/xcode/package.xcworkspace/contents.xcworkspacedata: -------------------------------------------------------------------------------- 1 | 2 | 4 | 6 | 7 | 8 | -------------------------------------------------------------------------------- /NonEmpty.playground/contents.xcplayground: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | -------------------------------------------------------------------------------- /Package.swift: -------------------------------------------------------------------------------- 1 | // swift-tools-version:5.1 2 | import PackageDescription 3 | 4 | let package = Package( 5 | name: "swift-nonempty", 6 | products: [ 7 | .library(name: "NonEmpty", targets: ["NonEmpty"]) 8 | ], 9 | targets: [ 10 | .target(name: "NonEmpty", dependencies: []), 11 | .testTarget(name: "NonEmptyTests", dependencies: ["NonEmpty"]), 12 | ] 13 | ) 14 | -------------------------------------------------------------------------------- /Makefile: -------------------------------------------------------------------------------- 1 | default: test-all 2 | 3 | test-all: test-linux test-swift 4 | 5 | test-linux: 6 | docker run \ 7 | --rm \ 8 | -v "$(PWD):$(PWD)" \ 9 | -w "$(PWD)" \ 10 | swift:5.3 \ 11 | bash -c 'make test-swift' 12 | 13 | test-swift: 14 | swift test \ 15 | --enable-test-discovery \ 16 | --parallel 17 | 18 | format: 19 | swift format --in-place --recursive ./Package.swift ./Sources ./Tests 20 | 21 | .PHONY: format test-all test-swift test-workspace 22 | -------------------------------------------------------------------------------- /Sources/NonEmpty/NonEmpty+ExpressibleByArrayLiteral.swift: -------------------------------------------------------------------------------- 1 | extension NonEmpty: ExpressibleByArrayLiteral where Collection: ExpressibleByArrayLiteral { 2 | public init(arrayLiteral elements: Element...) { 3 | precondition(!elements.isEmpty, "Can't construct \(Self.self) from empty array literal") 4 | let f = unsafeBitCast( 5 | Collection.init(arrayLiteral:), 6 | to: (([Element]) -> Collection).self 7 | ) 8 | self.init(rawValue: f(elements))! 9 | } 10 | } 11 | -------------------------------------------------------------------------------- /Sources/NonEmpty/NonEmpty+ExpressibleByDictionaryLiteral.swift: -------------------------------------------------------------------------------- 1 | extension NonEmpty: ExpressibleByDictionaryLiteral 2 | where Collection: ExpressibleByDictionaryLiteral { 3 | public init(dictionaryLiteral elements: (Collection.Key, Collection.Value)...) { 4 | precondition(!elements.isEmpty, "Can't construct \(Self.self) from empty dictionary literal") 5 | let f = unsafeBitCast( 6 | Collection.init(dictionaryLiteral:), 7 | to: (([(Collection.Key, Collection.Value)]) -> Collection).self 8 | ) 9 | self.init(rawValue: f(elements))! 10 | } 11 | } 12 | -------------------------------------------------------------------------------- /.github/workflows/format.yml: -------------------------------------------------------------------------------- 1 | name: Format 2 | 3 | on: 4 | push: 5 | branches: 6 | - main 7 | 8 | jobs: 9 | swift_format: 10 | name: swift-format 11 | runs-on: macOS-11 12 | steps: 13 | - uses: actions/checkout@v2 14 | - name: Xcode Select 15 | run: sudo xcode-select -s /Applications/Xcode_13.0.app 16 | - name: Tap 17 | run: brew tap pointfreeco/formulae 18 | - name: Install 19 | run: brew install Formulae/swift-format@5.5 20 | - name: Format 21 | run: make format 22 | - uses: stefanzweifel/git-auto-commit-action@v4 23 | with: 24 | commit_message: Run swift-format 25 | branch: 'main' 26 | env: 27 | GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }} 28 | -------------------------------------------------------------------------------- /.github/workflows/ci.yml: -------------------------------------------------------------------------------- 1 | name: CI 2 | 3 | on: 4 | push: 5 | branches: 6 | - main 7 | pull_request: 8 | branches: 9 | - '*' 10 | 11 | jobs: 12 | macos: 13 | name: macOS 14 | runs-on: macOS-latest 15 | strategy: 16 | matrix: 17 | xcode: 18 | - '11.7' 19 | - '12.4' 20 | - '12.5.1' 21 | - '13.0' 22 | steps: 23 | - uses: actions/checkout@v2 24 | - name: Select Xcode ${{ matrix.xcode }} 25 | run: sudo xcode-select -s /Applications/Xcode_${{ matrix.xcode }}.app 26 | - name: Run tests 27 | run: make test-swift 28 | - name: Build release 29 | run: swift build -c release 30 | 31 | linux: 32 | name: Linux 33 | runs-on: ubuntu-latest 34 | steps: 35 | - uses: actions/checkout@v2 36 | - name: Run tests 37 | run: make test-linux 38 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | MIT License 2 | 3 | Copyright (c) 2019 Point-Free, Inc. 4 | 5 | Permission is hereby granted, free of charge, to any person obtaining a copy 6 | of this software and associated documentation files (the "Software"), to deal 7 | in the Software without restriction, including without limitation the rights 8 | to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 9 | copies of the Software, and to permit persons to whom the Software is 10 | furnished to do so, subject to the following conditions: 11 | 12 | The above copyright notice and this permission notice shall be included in all 13 | copies or substantial portions of the Software. 14 | 15 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 | IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 | FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 18 | AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 | LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 20 | OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 21 | SOFTWARE. 22 | -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | # Xcode 2 | # 3 | # gitignore contributors: remember to update Global/Xcode.gitignore, Objective-C.gitignore & Swift.gitignore 4 | 5 | ## Build generated 6 | build/ 7 | DerivedData/ 8 | 9 | ## Various settings 10 | *.pbxuser 11 | !default.pbxuser 12 | *.mode1v3 13 | !default.mode1v3 14 | *.mode2v3 15 | !default.mode2v3 16 | *.perspectivev3 17 | !default.perspectivev3 18 | xcuserdata/ 19 | 20 | ## Other 21 | *.moved-aside 22 | *.xccheckout 23 | *.xcscmblueprint 24 | 25 | ## Obj-C/Swift specific 26 | *.hmap 27 | *.ipa 28 | *.dSYM.zip 29 | *.dSYM 30 | 31 | ## Playgrounds 32 | timeline.xctimeline 33 | playground.xcworkspace 34 | 35 | # Swift Package Manager 36 | # 37 | # Add this line if you want to avoid checking in source code from Swift Package Manager dependencies. 38 | # Packages/ 39 | # Package.pins 40 | .build/ 41 | 42 | # CocoaPods 43 | # 44 | # We recommend against adding the Pods directory to your .gitignore. However 45 | # you should judge for yourself, the pros and cons are mentioned at: 46 | # https://guides.cocoapods.org/using/using-cocoapods.html#should-i-check-the-pods-directory-into-source-control 47 | # 48 | # Pods/ 49 | 50 | # Carthage 51 | # 52 | # Add this line if you want to avoid checking in source code from Carthage dependencies. 53 | # Carthage/Checkouts 54 | 55 | Carthage/Build 56 | 57 | # fastlane 58 | # 59 | # It is recommended to not store the screenshots in the git repo. Instead, use fastlane to re-generate the 60 | # screenshots whenever they are needed. 61 | # For more information about the recommended setup visit: 62 | # https://docs.fastlane.tools/best-practices/source-control/#source-control 63 | 64 | fastlane/report.xml 65 | fastlane/Preview.html 66 | fastlane/screenshots 67 | fastlane/test_output 68 | 69 | .DS_Store 70 | -------------------------------------------------------------------------------- /Sources/NonEmpty/NonEmpty+RangeReplaceableCollection.swift: -------------------------------------------------------------------------------- 1 | // NB: `NonEmpty` does not conditionally conform to `RangeReplaceableCollection` because it contains destructive methods. 2 | extension NonEmpty where Collection: RangeReplaceableCollection { 3 | public init(_ head: Element, _ tail: Element...) { 4 | var tail = tail 5 | tail.insert(head, at: tail.startIndex) 6 | self.init(rawValue: Collection(tail))! 7 | } 8 | 9 | public init?(_ elements: S) where S: Sequence, Collection.Element == S.Element { 10 | self.init(rawValue: Collection(elements)) 11 | } 12 | 13 | public mutating func append(_ newElement: Element) { 14 | self.rawValue.append(newElement) 15 | } 16 | 17 | public mutating func append(contentsOf newElements: S) where Element == S.Element { 18 | self.rawValue.append(contentsOf: newElements) 19 | } 20 | 21 | public mutating func insert(_ newElement: Element, at i: Index) { 22 | self.rawValue.insert(newElement, at: i) 23 | } 24 | 25 | public mutating func insert( 26 | contentsOf newElements: S, at i: Index 27 | ) where S: Swift.Collection, Element == S.Element { 28 | self.rawValue.insert(contentsOf: newElements, at: i) 29 | } 30 | 31 | public static func += (lhs: inout Self, rhs: S) where Element == S.Element { 32 | lhs.append(contentsOf: rhs) 33 | } 34 | 35 | public static func + (lhs: Self, rhs: Self) -> Self { 36 | var lhs = lhs 37 | lhs += rhs 38 | return lhs 39 | } 40 | 41 | public static func + (lhs: Self, rhs: S) -> Self where Element == S.Element { 42 | var lhs = lhs 43 | lhs += rhs 44 | return lhs 45 | } 46 | 47 | public static func + (lhs: S, rhs: Self) -> Self where Element == S.Element { 48 | var rhs = rhs 49 | rhs.insert(contentsOf: ContiguousArray(lhs), at: rhs.startIndex) 50 | return rhs 51 | } 52 | } 53 | 54 | extension NonEmpty { 55 | public func joined( 56 | separator: S 57 | ) 58 | -> NonEmpty 59 | where Element == NonEmpty, S.Element == C.Element { 60 | NonEmpty(rawValue: C(self.rawValue.joined(separator: separator)))! 61 | } 62 | 63 | public func joined() -> NonEmpty 64 | where Element == NonEmpty { 65 | return joined(separator: C()) 66 | } 67 | } 68 | -------------------------------------------------------------------------------- /Sources/NonEmpty/NonEmpty+Dictionary.swift: -------------------------------------------------------------------------------- 1 | public typealias NonEmptyDictionary = NonEmpty<[Key: Value]> where Key: Hashable 2 | 3 | public protocol _DictionaryProtocol: Collection where Element == (key: Key, value: Value) { 4 | associatedtype Key: Hashable 5 | associatedtype Value 6 | var keys: Dictionary.Keys { get } 7 | subscript(key: Key) -> Value? { get set } 8 | mutating func merge( 9 | _ other: S, uniquingKeysWith combine: (Value, Value) throws -> Value 10 | ) rethrows where S.Element == (Key, Value) 11 | mutating func merge( 12 | _ other: [Key: Value], uniquingKeysWith combine: (Value, Value) throws -> Value 13 | ) rethrows 14 | @discardableResult mutating func removeValue(forKey key: Key) -> Value? 15 | @discardableResult mutating func updateValue(_ value: Value, forKey key: Key) -> Value? 16 | } 17 | 18 | extension Dictionary: _DictionaryProtocol {} 19 | 20 | extension NonEmpty where Collection: _DictionaryProtocol { 21 | public init(_ head: Element, _ tail: Collection) { 22 | guard !tail.keys.contains(head.key) else { fatalError("Dictionary contains duplicate key") } 23 | var tail = tail 24 | tail[head.key] = head.value 25 | self.init(rawValue: tail)! 26 | } 27 | 28 | public init( 29 | _ head: Element, 30 | _ tail: Collection, 31 | uniquingKeysWith combine: (Collection.Value, Collection.Value) throws -> Collection.Value 32 | ) rethrows { 33 | 34 | var tail = tail 35 | if let otherValue = tail.removeValue(forKey: head.0) { 36 | tail[head.key] = try combine(head.value, otherValue) 37 | } else { 38 | tail[head.key] = head.value 39 | } 40 | self.init(rawValue: tail)! 41 | } 42 | 43 | public subscript(key: Collection.Key) -> Collection.Value? { 44 | self.rawValue[key] 45 | } 46 | 47 | public mutating func merge( 48 | _ other: S, 49 | uniquingKeysWith combine: (Collection.Value, Collection.Value) throws -> Collection.Value 50 | ) rethrows where S.Element == (Collection.Key, Collection.Value) { 51 | 52 | try self.rawValue.merge(other, uniquingKeysWith: combine) 53 | } 54 | 55 | public func merging( 56 | _ other: S, 57 | uniquingKeysWith combine: (Collection.Value, Collection.Value) throws -> Collection.Value 58 | ) rethrows -> NonEmpty where S.Element == (Collection.Key, Collection.Value) { 59 | 60 | var copy = self 61 | try copy.merge(other, uniquingKeysWith: combine) 62 | return copy 63 | } 64 | 65 | public mutating func merge( 66 | _ other: [Collection.Key: Collection.Value], 67 | uniquingKeysWith combine: (Collection.Value, Collection.Value) throws -> Collection.Value 68 | ) rethrows { 69 | 70 | try self.rawValue.merge(other, uniquingKeysWith: combine) 71 | } 72 | 73 | public func merging( 74 | _ other: [Collection.Key: Collection.Value], 75 | uniquingKeysWith combine: (Collection.Value, Collection.Value) throws -> Collection.Value 76 | ) rethrows -> NonEmpty { 77 | 78 | var copy = self 79 | try copy.merge(other, uniquingKeysWith: combine) 80 | return copy 81 | } 82 | 83 | @discardableResult 84 | public mutating func updateValue(_ value: Collection.Value, forKey key: Collection.Key) 85 | -> Collection.Value? 86 | { 87 | self.rawValue.updateValue(value, forKey: key) 88 | } 89 | } 90 | 91 | extension NonEmpty where Collection: _DictionaryProtocol, Collection.Value: Equatable { 92 | public static func == (lhs: NonEmpty, rhs: NonEmpty) -> Bool { 93 | return Dictionary(uniqueKeysWithValues: Array(lhs)) 94 | == Dictionary(uniqueKeysWithValues: Array(rhs)) 95 | } 96 | } 97 | 98 | extension NonEmpty where Collection: _DictionaryProtocol & ExpressibleByDictionaryLiteral { 99 | public init(_ head: Element) { 100 | self.init(rawValue: [head.key: head.value])! 101 | } 102 | } 103 | -------------------------------------------------------------------------------- /Sources/NonEmpty/NonEmpty+String.swift: -------------------------------------------------------------------------------- 1 | public typealias NonEmptyString = NonEmpty 2 | 3 | extension NonEmptyString { 4 | @_disfavoredOverload 5 | public init?(_ value: T) where T: LosslessStringConvertible { 6 | self.init(String(value)) 7 | } 8 | } 9 | 10 | extension NonEmpty: ExpressibleByUnicodeScalarLiteral 11 | where Collection: ExpressibleByUnicodeScalarLiteral { 12 | public typealias UnicodeScalarLiteralType = Collection.UnicodeScalarLiteralType 13 | 14 | public init(unicodeScalarLiteral value: Collection.UnicodeScalarLiteralType) { 15 | self.init(rawValue: Collection(unicodeScalarLiteral: value))! 16 | } 17 | } 18 | 19 | extension NonEmpty: ExpressibleByExtendedGraphemeClusterLiteral 20 | where Collection: ExpressibleByExtendedGraphemeClusterLiteral { 21 | public typealias ExtendedGraphemeClusterLiteralType = Collection 22 | .ExtendedGraphemeClusterLiteralType 23 | 24 | public init(extendedGraphemeClusterLiteral value: Collection.ExtendedGraphemeClusterLiteralType) { 25 | self.init(rawValue: Collection(extendedGraphemeClusterLiteral: value))! 26 | } 27 | } 28 | 29 | extension NonEmpty: ExpressibleByStringLiteral where Collection: ExpressibleByStringLiteral { 30 | public typealias StringLiteralType = Collection.StringLiteralType 31 | 32 | public init(stringLiteral value: Collection.StringLiteralType) { 33 | self.init(rawValue: Collection(stringLiteral: value))! 34 | } 35 | } 36 | 37 | extension NonEmpty: TextOutputStreamable where Collection: TextOutputStreamable { 38 | public func write(to target: inout Target) where Target: TextOutputStream { 39 | self.rawValue.write(to: &target) 40 | } 41 | } 42 | 43 | extension NonEmpty: TextOutputStream where Collection: TextOutputStream { 44 | public mutating func write(_ string: String) { 45 | self.rawValue.write(string) 46 | } 47 | } 48 | 49 | extension NonEmpty: LosslessStringConvertible where Collection: LosslessStringConvertible { 50 | public init?(_ description: String) { 51 | guard let string = Collection(description) else { return nil } 52 | self.init(rawValue: string) 53 | } 54 | } 55 | 56 | extension NonEmpty: ExpressibleByStringInterpolation 57 | where 58 | Collection: ExpressibleByStringInterpolation, 59 | Collection.StringLiteralType == DefaultStringInterpolation.StringLiteralType 60 | {} 61 | 62 | extension NonEmpty where Collection: StringProtocol { 63 | public typealias UTF8View = Collection.UTF8View 64 | public typealias UTF16View = Collection.UTF16View 65 | public typealias UnicodeScalarView = Collection.UnicodeScalarView 66 | 67 | public var utf8: UTF8View { self.rawValue.utf8 } 68 | public var utf16: UTF16View { self.rawValue.utf16 } 69 | public var unicodeScalars: UnicodeScalarView { self.rawValue.unicodeScalars } 70 | 71 | public init( 72 | decoding codeUnits: C, as sourceEncoding: Encoding.Type 73 | ) where C: Swift.Collection, Encoding: _UnicodeEncoding, C.Element == Encoding.CodeUnit { 74 | self.init(rawValue: Collection(decoding: codeUnits, as: sourceEncoding))! 75 | } 76 | 77 | public init(cString nullTerminatedUTF8: UnsafePointer) { 78 | self.init(rawValue: Collection(cString: nullTerminatedUTF8))! 79 | } 80 | 81 | public init( 82 | decodingCString nullTerminatedCodeUnits: UnsafePointer, 83 | as sourceEncoding: Encoding.Type 84 | ) where Encoding: _UnicodeEncoding { 85 | self.init(rawValue: Collection(decodingCString: nullTerminatedCodeUnits, as: sourceEncoding))! 86 | } 87 | 88 | public func withCString(_ body: (UnsafePointer) throws -> Result) rethrows 89 | -> Result 90 | { 91 | try self.rawValue.withCString(body) 92 | } 93 | 94 | public func withCString( 95 | encodedAs targetEncoding: Encoding.Type, 96 | _ body: (UnsafePointer) throws -> Result 97 | ) rethrows -> Result where Encoding: _UnicodeEncoding { 98 | try self.rawValue.withCString(encodedAs: targetEncoding, body) 99 | } 100 | 101 | public func lowercased() -> NonEmptyString { 102 | NonEmptyString(self.rawValue.lowercased())! 103 | } 104 | 105 | public func uppercased() -> NonEmptyString { 106 | NonEmptyString(self.rawValue.uppercased())! 107 | } 108 | } 109 | -------------------------------------------------------------------------------- /Sources/NonEmpty/NonEmpty+SetAlgebra.swift: -------------------------------------------------------------------------------- 1 | public typealias NonEmptySet = NonEmpty> where Element: Hashable 2 | 3 | // NB: `NonEmpty` does not conditionally conform to `SetAlgebra` because it contains destructive methods. 4 | extension NonEmpty where Collection: SetAlgebra, Collection.Element: Hashable { 5 | public init(_ head: Collection.Element, _ tail: Collection.Element...) { 6 | var tail = Collection(tail) 7 | tail.insert(head) 8 | self.init(rawValue: tail)! 9 | } 10 | 11 | public init?(_ elements: S) where S: Sequence, Collection.Element == S.Element { 12 | self.init(rawValue: Collection(elements)) 13 | } 14 | 15 | public func contains(_ member: Collection.Element) -> Bool { 16 | self.rawValue.contains(member) 17 | } 18 | 19 | @_disfavoredOverload 20 | public func union(_ other: NonEmpty) -> NonEmpty { 21 | var copy = self 22 | copy.formUnion(other) 23 | return copy 24 | } 25 | 26 | public func union(_ other: Collection) -> NonEmpty { 27 | var copy = self 28 | copy.formUnion(other) 29 | return copy 30 | } 31 | 32 | @_disfavoredOverload 33 | public func intersection(_ other: NonEmpty) -> Collection { 34 | self.rawValue.intersection(other.rawValue) 35 | } 36 | 37 | public func intersection(_ other: Collection) -> Collection { 38 | self.rawValue.intersection(other) 39 | } 40 | 41 | @_disfavoredOverload 42 | public func symmetricDifference(_ other: NonEmpty) -> Collection { 43 | self.rawValue.symmetricDifference(other.rawValue) 44 | } 45 | 46 | public func symmetricDifference(_ other: Collection) -> Collection { 47 | self.rawValue.symmetricDifference(other) 48 | } 49 | 50 | @discardableResult 51 | public mutating func insert(_ newMember: Collection.Element) -> ( 52 | inserted: Bool, memberAfterInsert: Collection.Element 53 | ) { 54 | self.rawValue.insert(newMember) 55 | } 56 | 57 | @discardableResult 58 | public mutating func update(with newMember: Collection.Element) -> Collection.Element? { 59 | self.rawValue.update(with: newMember) 60 | } 61 | 62 | @_disfavoredOverload 63 | public mutating func formUnion(_ other: NonEmpty) { 64 | self.rawValue.formUnion(other.rawValue) 65 | } 66 | 67 | public mutating func formUnion(_ other: Collection) { 68 | self.rawValue.formUnion(other) 69 | } 70 | 71 | @_disfavoredOverload 72 | public func subtracting(_ other: NonEmpty) -> Collection { 73 | self.rawValue.subtracting(other.rawValue) 74 | } 75 | 76 | public func subtracting(_ other: Collection) -> Collection { 77 | self.rawValue.subtracting(other) 78 | } 79 | 80 | @_disfavoredOverload 81 | public func isDisjoint(with other: NonEmpty) -> Bool { 82 | self.rawValue.isDisjoint(with: other.rawValue) 83 | } 84 | 85 | public func isDisjoint(with other: Collection) -> Bool { 86 | self.rawValue.isDisjoint(with: other) 87 | } 88 | 89 | @_disfavoredOverload 90 | public func isSubset(of other: NonEmpty) -> Bool { 91 | self.rawValue.isSubset(of: other.rawValue) 92 | } 93 | 94 | public func isSubset(of other: Collection) -> Bool { 95 | self.rawValue.isSubset(of: other) 96 | } 97 | 98 | @_disfavoredOverload 99 | public func isSuperset(of other: NonEmpty) -> Bool { 100 | self.rawValue.isSuperset(of: other.rawValue) 101 | } 102 | 103 | public func isSuperset(of other: Collection) -> Bool { 104 | self.rawValue.isSuperset(of: other) 105 | } 106 | 107 | @_disfavoredOverload 108 | public func isStrictSubset(of other: NonEmpty) -> Bool { 109 | self.rawValue.isStrictSubset(of: other.rawValue) 110 | } 111 | 112 | public func isStrictSubset(of other: Collection) -> Bool { 113 | self.rawValue.isStrictSubset(of: other) 114 | } 115 | 116 | @_disfavoredOverload 117 | public func isStrictSuperset(of other: NonEmpty) -> Bool { 118 | self.rawValue.isStrictSuperset(of: other.rawValue) 119 | } 120 | 121 | public func isStrictSuperset(of other: Collection) -> Bool { 122 | self.rawValue.isStrictSuperset(of: other) 123 | } 124 | } 125 | 126 | extension SetAlgebra where Self: Collection, Element: Hashable { 127 | public func union(_ other: NonEmpty) -> NonEmpty { 128 | var copy = other 129 | copy.formUnion(self) 130 | return copy 131 | } 132 | 133 | public func intersection(_ other: NonEmpty) -> Self { 134 | self.intersection(other.rawValue) 135 | } 136 | 137 | public func symmetricDifference(_ other: NonEmpty) -> Self { 138 | self.symmetricDifference(other.rawValue) 139 | } 140 | 141 | public mutating func formUnion(_ other: NonEmpty) { 142 | self.formUnion(other.rawValue) 143 | } 144 | 145 | public func subtracting(_ other: NonEmpty) -> Self { 146 | self.subtracting(other.rawValue) 147 | } 148 | 149 | public func isDisjoint(with other: NonEmpty) -> Bool { 150 | self.isDisjoint(with: other.rawValue) 151 | } 152 | 153 | public func isSubset(of other: NonEmpty) -> Bool { 154 | self.isSubset(of: other.rawValue) 155 | } 156 | 157 | public func isSuperset(of other: NonEmpty) -> Bool { 158 | self.isSuperset(of: other.rawValue) 159 | } 160 | 161 | public func isStrictSubset(of other: NonEmpty) -> Bool { 162 | self.isStrictSubset(of: other.rawValue) 163 | } 164 | 165 | public func isStrictSuperset(of other: NonEmpty) -> Bool { 166 | self.isStrictSuperset(of: other.rawValue) 167 | } 168 | } 169 | -------------------------------------------------------------------------------- /Sources/NonEmpty/NonEmpty.swift: -------------------------------------------------------------------------------- 1 | @dynamicMemberLookup 2 | public struct NonEmpty: Swift.Collection { 3 | public typealias Element = Collection.Element 4 | public typealias Index = Collection.Index 5 | 6 | public internal(set) var rawValue: Collection 7 | 8 | public init?(rawValue: Collection) { 9 | guard !rawValue.isEmpty else { return nil } 10 | self.rawValue = rawValue 11 | } 12 | 13 | public subscript(dynamicMember keyPath: KeyPath) -> Subject { 14 | self.rawValue[keyPath: keyPath] 15 | } 16 | 17 | public var startIndex: Index { self.rawValue.startIndex } 18 | 19 | public var endIndex: Index { self.rawValue.endIndex } 20 | 21 | public subscript(position: Index) -> Element { self.rawValue[position] } 22 | 23 | public func index(after i: Index) -> Index { 24 | self.rawValue.index(after: i) 25 | } 26 | 27 | public var first: Element { self.rawValue.first! } 28 | 29 | public func max(by areInIncreasingOrder: (Element, Element) throws -> Bool) rethrows -> Element { 30 | try self.rawValue.max(by: areInIncreasingOrder)! 31 | } 32 | 33 | public func min(by areInIncreasingOrder: (Element, Element) throws -> Bool) rethrows -> Element { 34 | try self.rawValue.min(by: areInIncreasingOrder)! 35 | } 36 | 37 | public func sorted( 38 | by areInIncreasingOrder: (Element, Element) throws -> Bool 39 | ) rethrows -> NonEmpty<[Element]> { 40 | NonEmpty<[Element]>(rawValue: try self.rawValue.sorted(by: areInIncreasingOrder))! 41 | } 42 | 43 | public func randomElement(using generator: inout T) -> Element where T: RandomNumberGenerator { 44 | self.rawValue.randomElement(using: &generator)! 45 | } 46 | 47 | public func randomElement() -> Element { 48 | self.rawValue.randomElement()! 49 | } 50 | 51 | public func shuffled(using generator: inout T) -> NonEmpty<[Element]> 52 | where T: RandomNumberGenerator { 53 | NonEmpty<[Element]>(rawValue: self.rawValue.shuffled(using: &generator))! 54 | } 55 | 56 | public func shuffled() -> NonEmpty<[Element]> { 57 | NonEmpty<[Element]>(rawValue: self.rawValue.shuffled())! 58 | } 59 | 60 | public func map(_ transform: (Element) throws -> T) rethrows -> NonEmpty<[T]> { 61 | NonEmpty<[T]>(rawValue: try self.rawValue.map(transform))! 62 | } 63 | 64 | public func flatMap( 65 | _ transform: (Element) throws -> NonEmpty 66 | ) rethrows -> NonEmpty<[SegmentOfResult.Element]> where SegmentOfResult: Sequence { 67 | NonEmpty<[SegmentOfResult.Element]>(rawValue: try self.rawValue.flatMap(transform))! 68 | } 69 | } 70 | 71 | extension NonEmpty: CustomStringConvertible { 72 | public var description: String { 73 | return String(describing: self.rawValue) 74 | } 75 | } 76 | 77 | extension NonEmpty: Equatable where Collection: Equatable {} 78 | 79 | extension NonEmpty: Hashable where Collection: Hashable {} 80 | 81 | extension NonEmpty: Comparable where Collection: Comparable { 82 | public static func < (lhs: Self, rhs: Self) -> Bool { 83 | lhs.rawValue < rhs.rawValue 84 | } 85 | } 86 | 87 | #if canImport(_Concurrency) && compiler(>=5.5) 88 | extension NonEmpty: Sendable where Collection: Sendable {} 89 | #endif 90 | 91 | extension NonEmpty: Encodable where Collection: Encodable { 92 | public func encode(to encoder: Encoder) throws { 93 | do { 94 | var container = encoder.singleValueContainer() 95 | try container.encode(self.rawValue) 96 | } catch { 97 | try self.rawValue.encode(to: encoder) 98 | } 99 | } 100 | } 101 | 102 | extension NonEmpty: Decodable where Collection: Decodable { 103 | public init(from decoder: Decoder) throws { 104 | let collection: Collection 105 | do { 106 | collection = try decoder.singleValueContainer().decode(Collection.self) 107 | } catch { 108 | collection = try Collection(from: decoder) 109 | } 110 | 111 | guard !collection.isEmpty else { 112 | throw DecodingError.dataCorrupted( 113 | .init(codingPath: decoder.codingPath, debugDescription: "Non-empty collection expected") 114 | ) 115 | } 116 | self.init(rawValue: collection)! 117 | } 118 | } 119 | 120 | extension NonEmpty: RawRepresentable {} 121 | 122 | extension NonEmpty where Collection.Element: Comparable { 123 | public func max() -> Element { 124 | self.rawValue.max()! 125 | } 126 | 127 | public func min() -> Element { 128 | self.rawValue.min()! 129 | } 130 | 131 | public func sorted() -> NonEmpty<[Element]> { 132 | return NonEmpty<[Element]>(rawValue: self.rawValue.sorted())! 133 | } 134 | } 135 | 136 | extension NonEmpty: BidirectionalCollection where Collection: BidirectionalCollection { 137 | public func index(before i: Index) -> Index { 138 | self.rawValue.index(before: i) 139 | } 140 | 141 | public var last: Element { self.rawValue.last! } 142 | } 143 | 144 | extension NonEmpty: MutableCollection where Collection: MutableCollection { 145 | public subscript(position: Index) -> Element { 146 | _read { yield self.rawValue[position] } 147 | _modify { yield &self.rawValue[position] } 148 | } 149 | } 150 | 151 | extension NonEmpty: RandomAccessCollection where Collection: RandomAccessCollection {} 152 | 153 | extension NonEmpty where Collection: MutableCollection & RandomAccessCollection { 154 | public mutating func shuffle(using generator: inout T) { 155 | self.rawValue.shuffle(using: &generator) 156 | } 157 | } 158 | 159 | public typealias NonEmptyArray = NonEmpty<[Element]> 160 | -------------------------------------------------------------------------------- /.github/CODE_OF_CONDUCT.md: -------------------------------------------------------------------------------- 1 | # Contributor Covenant Code of Conduct 2 | 3 | ## Our Pledge 4 | 5 | We as members, contributors, and leaders pledge to make participation in our 6 | community a harassment-free experience for everyone, regardless of age, body 7 | size, visible or invisible disability, ethnicity, sex characteristics, gender 8 | identity and expression, level of experience, education, socio-economic status, 9 | nationality, personal appearance, race, caste, color, religion, or sexual 10 | identity and orientation. 11 | 12 | We pledge to act and interact in ways that contribute to an open, welcoming, 13 | diverse, inclusive, and healthy community. 14 | 15 | ## Our Standards 16 | 17 | Examples of behavior that contributes to a positive environment for our 18 | community include: 19 | 20 | * Demonstrating empathy and kindness toward other people 21 | * Being respectful of differing opinions, viewpoints, and experiences 22 | * Giving and gracefully accepting constructive feedback 23 | * Accepting responsibility and apologizing to those affected by our mistakes, 24 | and learning from the experience 25 | * Focusing on what is best not just for us as individuals, but for the overall 26 | community 27 | 28 | Examples of unacceptable behavior include: 29 | 30 | * The use of sexualized language or imagery, and sexual attention or advances of 31 | any kind 32 | * Trolling, insulting or derogatory comments, and personal or political attacks 33 | * Public or private harassment 34 | * Publishing others' private information, such as a physical or email address, 35 | without their explicit permission 36 | * Other conduct which could reasonably be considered inappropriate in a 37 | professional setting 38 | 39 | ## Enforcement Responsibilities 40 | 41 | Community leaders are responsible for clarifying and enforcing our standards of 42 | acceptable behavior and will take appropriate and fair corrective action in 43 | response to any behavior that they deem inappropriate, threatening, offensive, 44 | or harmful. 45 | 46 | Community leaders have the right and responsibility to remove, edit, or reject 47 | comments, commits, code, wiki edits, issues, and other contributions that are 48 | not aligned to this Code of Conduct, and will communicate reasons for moderation 49 | decisions when appropriate. 50 | 51 | ## Scope 52 | 53 | This Code of Conduct applies within all community spaces, and also applies when 54 | an individual is officially representing the community in public spaces. 55 | Examples of representing our community include using an official e-mail address, 56 | posting via an official social media account, or acting as an appointed 57 | representative at an online or offline event. 58 | 59 | ## Enforcement 60 | 61 | Instances of abusive, harassing, or otherwise unacceptable behavior may be 62 | reported to the community leaders responsible for enforcement at 63 | . 64 | All complaints will be reviewed and investigated promptly and fairly. 65 | 66 | All community leaders are obligated to respect the privacy and security of the 67 | reporter of any incident. 68 | 69 | ## Enforcement Guidelines 70 | 71 | Community leaders will follow these Community Impact Guidelines in determining 72 | the consequences for any action they deem in violation of this Code of Conduct: 73 | 74 | ### 1. Correction 75 | 76 | **Community Impact**: Use of inappropriate language or other behavior deemed 77 | unprofessional or unwelcome in the community. 78 | 79 | **Consequence**: A private, written warning from community leaders, providing 80 | clarity around the nature of the violation and an explanation of why the 81 | behavior was inappropriate. A public apology may be requested. 82 | 83 | ### 2. Warning 84 | 85 | **Community Impact**: A violation through a single incident or series of 86 | actions. 87 | 88 | **Consequence**: A warning with consequences for continued behavior. No 89 | interaction with the people involved, including unsolicited interaction with 90 | those enforcing the Code of Conduct, for a specified period of time. This 91 | includes avoiding interactions in community spaces as well as external channels 92 | like social media. Violating these terms may lead to a temporary or permanent 93 | ban. 94 | 95 | ### 3. Temporary Ban 96 | 97 | **Community Impact**: A serious violation of community standards, including 98 | sustained inappropriate behavior. 99 | 100 | **Consequence**: A temporary ban from any sort of interaction or public 101 | communication with the community for a specified period of time. No public or 102 | private interaction with the people involved, including unsolicited interaction 103 | with those enforcing the Code of Conduct, is allowed during this period. 104 | Violating these terms may lead to a permanent ban. 105 | 106 | ### 4. Permanent Ban 107 | 108 | **Community Impact**: Demonstrating a pattern of violation of community 109 | standards, including sustained inappropriate behavior, harassment of an 110 | individual, or aggression toward or disparagement of classes of individuals. 111 | 112 | **Consequence**: A permanent ban from any sort of public interaction within the 113 | community. 114 | 115 | ## Attribution 116 | 117 | This Code of Conduct is adapted from the [Contributor Covenant][homepage], 118 | version 2.1, available at 119 | [https://www.contributor-covenant.org/version/2/1/code_of_conduct.html][v2.1]. 120 | 121 | Community Impact Guidelines were inspired by 122 | [Mozilla's code of conduct enforcement ladder][Mozilla CoC]. 123 | 124 | For answers to common questions about this code of conduct, see the FAQ at 125 | [https://www.contributor-covenant.org/faq][FAQ]. Translations are available at 126 | [https://www.contributor-covenant.org/translations][translations]. 127 | 128 | [homepage]: https://www.contributor-covenant.org 129 | [v2.1]: https://www.contributor-covenant.org/version/2/1/code_of_conduct.html 130 | [Mozilla CoC]: https://github.com/mozilla/diversity 131 | [FAQ]: https://www.contributor-covenant.org/faq 132 | [translations]: https://www.contributor-covenant.org/translations 133 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # 🎁 NonEmpty 2 | 3 | [![CI](https://github.com/pointfreeco/swift-nonempty/workflows/CI/badge.svg)](https://actions-badge.atrox.dev/pointfreeco/swift-nonempty/goto) 4 | [![](https://img.shields.io/endpoint?url=https%3A%2F%2Fswiftpackageindex.com%2Fapi%2Fpackages%2Fpointfreeco%2Fswift-nonempty%2Fbadge%3Ftype%3Dswift-versions)](https://swiftpackageindex.com/pointfreeco/swift-nonempty) 5 | [![](https://img.shields.io/endpoint?url=https%3A%2F%2Fswiftpackageindex.com%2Fapi%2Fpackages%2Fpointfreeco%2Fswift-nonempty%2Fbadge%3Ftype%3Dplatforms)](https://swiftpackageindex.com/pointfreeco/swift-nonempty) 6 | 7 | A compile-time guarantee that a collection contains a value. 8 | 9 | ## Motivation 10 | 11 | We often work with collections that should _never_ be empty, but the type system makes no such guarantees, so we're forced to handle that empty case, often with `if` and `guard` statements. `NonEmpty` is a lightweight type that can transform _any_ collection type into a non-empty version. Some examples: 12 | 13 | ```swift 14 | // 1.) A non-empty array of integers 15 | let xs = NonEmpty<[Int]>(1, 2, 3, 4) 16 | xs.first + 1 // `first` is non-optional since it's guaranteed to be present 17 | 18 | // 2.) A non-empty set of integers 19 | let ys = NonEmpty>(1, 1, 2, 2, 3, 4) 20 | ys.forEach { print($0) } // => 1, 2, 3, 4 21 | 22 | // 3.) A non-empty dictionary of values 23 | let zs = NonEmpty<[Int: String]>((1, "one"), [2: "two", 3: "three"]) 24 | 25 | // 4.) A non-empty string 26 | let helloWorld = NonEmpty("H", "ello World") 27 | print("\(helloWorld)!") // "Hello World!" 28 | ``` 29 | 30 | ## Applications 31 | 32 | There are many applications of non-empty collection types but it can be hard to see since the Swift standard library does not give us this type. Here are just a few such applications: 33 | 34 | ### Strengthen 1st party APIs 35 | 36 | Many APIs take and return empty-able arrays when they can in fact guarantee that the arrays are non-empty. Consider a `groupBy` function: 37 | 38 | ```swift 39 | extension Sequence { 40 | func groupBy(_ f: (Element) -> A) -> [A: [Element]] { 41 | // Unimplemented 42 | } 43 | } 44 | 45 | Array(1...10) 46 | .groupBy { $0 % 3 } 47 | // [0: [3, 6, 9], 1: [1, 4, 7, 10], 2: [2, 5, 8]] 48 | ``` 49 | 50 | However, the array `[Element]` inside the return type `[A: [Element]]` can be guaranteed to never be empty, for the only way to produce an `A` is from an `Element`. Therefore the signature of this function could be strengthened to be: 51 | 52 | ```swift 53 | extension Sequence { 54 | func groupBy(_ f: (Element) -> A) -> [A: NonEmpty<[Element]>] { 55 | // Unimplemented 56 | } 57 | } 58 | ``` 59 | 60 | ### Better interface with 3rd party APIs 61 | 62 | Sometimes a 3rd party API we interact with requires non-empty collections of values, and so in our code we should use non-empty types so that we can be sure to never send an empty values to the API. A good example of this is [GraphQL](https://graphql.org/). Here is a very simple query builder and printer: 63 | 64 | ```swift 65 | enum UserField: String { case id, name, email } 66 | 67 | func query(_ fields: Set) -> String { 68 | return (["{"] + fields.map { " \($0.rawValue)" } + ["}"]) 69 | .joined() 70 | } 71 | 72 | print(query([.name, .email])) 73 | // { 74 | // name 75 | // email 76 | // } 77 | 78 | print(query([])) 79 | // { 80 | // } 81 | ``` 82 | 83 | This last query is a programmer error, and will cause the GraphQL server to send back an error because it is not valid to send an empty query. We can prevent this from ever happening by instead forcing our query builder to work with non-empty sets: 84 | 85 | ```swift 86 | func query(_ fields: NonEmptySet) -> String { 87 | return (["{"] + fields.map { " \($0.rawValue)" } + ["}"]) 88 | .joined() 89 | } 90 | 91 | print(query(.init(.name, .email))) 92 | // { 93 | // name 94 | // email 95 | // } 96 | 97 | print(query(.init())) 98 | // 🛑 Does not compile 99 | ``` 100 | 101 | ### More expressive data structures 102 | 103 | A popular type in the Swift community (and other languages), is the `Result` type. It allows you to express a value that can be successful or be a failure. There's a related type that is also handy, called the `Validated` type: 104 | 105 | ```swift 106 | enum Validated { 107 | case valid(Value) 108 | case invalid([Error]) 109 | } 110 | ``` 111 | 112 | A value of type `Validated` is either valid, and hence comes with a `Value`, or it is invalid, and comes with an array of errors that describe what all is wrong with the value. For example: 113 | 114 | ```swift 115 | let validatedPassword: Validated = 116 | .invalid(["Password is too short.", "Password must contain at least one number."]) 117 | ``` 118 | 119 | This is useful because it allows you to describe all of the things wrong with a value, not just one thing. However, it doesn't make a lot of sense if we use an empty array of the list of validation errors: 120 | 121 | ```swift 122 | let validatedPassword: Validated = .invalid([]) // ??? 123 | ``` 124 | 125 | Instead, we should strengthen the `Validated` type to use a non-empty array: 126 | 127 | ```swift 128 | enum Validated { 129 | case valid(Value) 130 | case invalid(NonEmptyArray) 131 | } 132 | ``` 133 | 134 | And now this is a compiler error: 135 | 136 | ```swift 137 | let validatedPassword: Validated = .invalid(.init([])) // 🛑 138 | ``` 139 | 140 | ## Installation 141 | 142 | If you want to use NonEmpty in a project that uses [SwiftPM](https://swift.org/package-manager/), it's as simple as adding a dependency to your `Package.swift`: 143 | 144 | ``` swift 145 | dependencies: [ 146 | .package(url: "https://github.com/pointfreeco/swift-nonempty.git", from: "0.3.0") 147 | ] 148 | ``` 149 | 150 | ## Interested in learning more? 151 | 152 | These concepts (and more) are explored thoroughly in [Point-Free](https://www.pointfree.co), a video series exploring functional programming and Swift hosted by [Brandon Williams](https://twitter.com/mbrandonw) and [Stephen Celis](https://twitter.com/stephencelis). 153 | 154 | NonEmpty was first explored in [Episode #20](https://www.pointfree.co/episodes/ep20-nonempty): 155 | 156 | 157 | video poster image 158 | 159 | 160 | ## License 161 | 162 | All modules are released under the MIT license. See [LICENSE](LICENSE) for details. 163 | -------------------------------------------------------------------------------- /Tests/NonEmptyTests/NonEmptyTests.swift: -------------------------------------------------------------------------------- 1 | import XCTest 2 | 3 | @testable import NonEmpty 4 | 5 | #if canImport(SwiftUI) 6 | import SwiftUI 7 | #endif 8 | 9 | final class NonEmptyTests: XCTestCase { 10 | func testCollection() { 11 | let xs = NonEmptyArray(1, 2, 3) 12 | 13 | XCTAssertEqual(3, xs.count) 14 | XCTAssertEqual(2, xs.first + 1) 15 | XCTAssertEqual( 16 | xs, 17 | NonEmptyArray(NonEmptyArray(1), NonEmptyArray(2), NonEmptyArray(3)).flatMap { $0 } 18 | ) 19 | XCTAssertEqual( 20 | NonEmptyArray("1", "2", "3"), 21 | xs.map(String.init) 22 | ) 23 | XCTAssertEqual(4, xs.min(by: >) + 1) 24 | XCTAssertEqual(2, xs.max(by: >) + 1) 25 | XCTAssertEqual(NonEmptyArray(3, 2, 1), xs.sorted(by: >)) 26 | XCTAssertEqual([1, 2, 3], Array(xs)) 27 | 28 | XCTAssertEqual(NonEmptyArray(1, 2, 3, 1, 2, 3), xs + xs) 29 | } 30 | 31 | func testBidirectionalCollection() { 32 | XCTAssertEqual(4, NonEmptyArray(1, 2, 3).last + 1) 33 | XCTAssertEqual(4, NonEmptyArray(3).last + 1) 34 | } 35 | 36 | func testMutableCollection() { 37 | var xs = NonEmptyArray(1, 2, 3) 38 | xs[0] = 42 39 | xs[1] = 43 40 | XCTAssertEqual(42, xs[0]) 41 | XCTAssertEqual(43, xs[1]) 42 | } 43 | 44 | func testRangeSubscript() { 45 | let xs = NonEmptyArray(1, 2, 3, 4) 46 | XCTAssertEqual([2, 3], xs[1...2]) 47 | } 48 | 49 | func testRangeReplaceableCollection() { 50 | var xs = NonEmptyArray(1, 2, 3) 51 | 52 | XCTAssertEqual(xs, NonEmptyArray([1, 2, 3])) 53 | 54 | xs.append(4) 55 | XCTAssertEqual(NonEmptyArray(1, 2, 3, 4), xs) 56 | xs.append(contentsOf: [5, 6]) 57 | XCTAssertEqual(NonEmptyArray(1, 2, 3, 4, 5, 6), xs) 58 | xs.insert(0, at: 0) 59 | XCTAssertEqual(NonEmptyArray(0, 1, 2, 3, 4, 5, 6), xs) 60 | xs.insert(contentsOf: [-2, -1], at: 0) 61 | XCTAssertEqual(NonEmptyArray(-2, -1, 0, 1, 2, 3, 4, 5, 6), xs) 62 | xs.insert(contentsOf: [], at: 0) 63 | XCTAssertEqual(NonEmptyArray(-2, -1, 0, 1, 2, 3, 4, 5, 6), xs) 64 | xs.insert(7, at: 9) 65 | XCTAssertEqual(NonEmptyArray(-2, -1, 0, 1, 2, 3, 4, 5, 6, 7), xs) 66 | xs.insert(contentsOf: [8, 9], at: 10) 67 | XCTAssertEqual(NonEmptyArray(-2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9), xs) 68 | xs += [10] 69 | XCTAssertEqual(NonEmptyArray(-2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10), xs) 70 | XCTAssertEqual(NonEmptyArray(-2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11), xs + [11]) 71 | } 72 | 73 | func testSetAlgebra() { 74 | XCTAssertEqual(3, NonEmptySet(1, 1, 2, 3).count) 75 | 76 | XCTAssertTrue(NonEmptySet(1, 2, 3).contains(1)) 77 | XCTAssertTrue(NonEmptySet(1, 2, 3).contains(3)) 78 | XCTAssertFalse(NonEmptySet(1, 2, 3).contains(4)) 79 | 80 | XCTAssertEqual(NonEmptySet(1, 2, 3, 4, 5, 6), NonEmptySet(1, 2, 3).union(NonEmptySet(4, 5, 6))) 81 | XCTAssertEqual(NonEmptySet(1, 2, 3, 4, 5, 6), NonEmptySet(1, 2, 3).union([4, 5, 6])) 82 | XCTAssertEqual([3], NonEmptySet(1, 2, 3).intersection(NonEmptySet(3, 4, 5))) 83 | XCTAssertEqual([3], NonEmptySet(1, 2, 3).intersection([3, 4, 5])) 84 | XCTAssertEqual([1, 2, 4, 5], NonEmptySet(1, 2, 3).symmetricDifference(NonEmptySet(3, 4, 5))) 85 | XCTAssertEqual([1, 2, 4, 5], NonEmptySet(1, 2, 3).symmetricDifference([3, 4, 5])) 86 | 87 | var xs = NonEmptySet(1, 2, 3) 88 | 89 | XCTAssertEqual(xs, NonEmptySet([1, 2, 3])) 90 | 91 | var (inserted, memberAfterInsert) = xs.insert(1) 92 | XCTAssertFalse(inserted) 93 | XCTAssertEqual(1, memberAfterInsert) 94 | XCTAssertEqual(3, xs.count) 95 | (inserted, memberAfterInsert) = xs.insert(4) 96 | XCTAssertTrue(inserted) 97 | XCTAssertEqual(4, memberAfterInsert) 98 | XCTAssertEqual(4, xs.count) 99 | xs.formUnion(NonEmptySet(5, 6)) 100 | XCTAssertEqual(NonEmptySet(1, 2, 3, 4, 5, 6), xs) 101 | xs.formUnion([7, 8]) 102 | XCTAssertEqual(NonEmptySet(1, 2, 3, 4, 5, 6, 7, 8), xs) 103 | 104 | XCTAssertEqual([2, 3], NonEmptySet(1, 2, 3).subtracting(NonEmptySet(1))) 105 | XCTAssertEqual([1, 2], NonEmptySet(1, 2, 3).subtracting(NonEmptySet(3))) 106 | XCTAssertEqual([2, 3], NonEmptySet(1, 2, 3).subtracting([1])) 107 | XCTAssertEqual([1, 2], NonEmptySet(1, 2, 3).subtracting([3])) 108 | 109 | XCTAssertTrue(NonEmptySet(1, 2, 3).isSubset(of: NonEmptySet(1, 2, 3))) 110 | XCTAssertTrue(NonEmptySet(1, 2, 3).isSubset(of: [1, 2, 3])) 111 | XCTAssertTrue(NonEmptySet(1, 2, 3).isStrictSubset(of: NonEmptySet(1, 2, 3, 4))) 112 | XCTAssertTrue(NonEmptySet(1, 2, 3).isStrictSubset(of: [1, 2, 3, 4])) 113 | XCTAssertFalse(NonEmptySet(1, 2, 3).isStrictSubset(of: NonEmptySet(1, 2, 3))) 114 | XCTAssertFalse(NonEmptySet(1, 2, 3).isStrictSubset(of: [1, 2, 3])) 115 | XCTAssertTrue(NonEmptySet(1, 2, 3).isSuperset(of: NonEmptySet(1, 2, 3))) 116 | XCTAssertTrue(NonEmptySet(1, 2, 3).isSuperset(of: [1, 2, 3])) 117 | XCTAssertTrue(NonEmptySet(1, 2, 3, 4).isStrictSuperset(of: NonEmptySet(1, 2, 3))) 118 | XCTAssertTrue(NonEmptySet(1, 2, 3, 4).isStrictSuperset(of: [1, 2, 3])) 119 | XCTAssertFalse(NonEmptySet(1, 2, 3).isStrictSuperset(of: NonEmptySet(1, 2, 3))) 120 | XCTAssertFalse(NonEmptySet(1, 2, 3).isStrictSuperset(of: [1, 2, 3])) 121 | XCTAssertTrue(NonEmptySet(1, 2, 3).isDisjoint(with: NonEmptySet(4, 5, 6))) 122 | XCTAssertTrue(NonEmptySet(1, 2, 3).isDisjoint(with: [4, 5, 6])) 123 | XCTAssertFalse(NonEmptySet(1, 2, 3).isDisjoint(with: NonEmptySet(3, 4, 5))) 124 | XCTAssertFalse(NonEmptySet(1, 2, 3).isDisjoint(with: [3, 4, 5])) 125 | } 126 | 127 | func testExpressibleByArrayLiteral() { 128 | let xs = NonEmpty<[Int]>(1, 2, 3) 129 | let ys: NonEmpty<[Int]> = [1, 2, 3] 130 | 131 | XCTAssertEqual(xs, ys) 132 | XCTAssertEqual(xs, [1, 2, 3]) 133 | XCTAssertNotEqual(xs, [2, 1, 3]) 134 | } 135 | 136 | func testExpressibleByDictionaryLiteral() { 137 | let xs = NonEmpty<[String: String]>(("a", "test"), ["b": "demo"]) 138 | let ys: NonEmpty<[String: String]> = ["a": "test", "b": "demo"] 139 | 140 | XCTAssertEqual(xs, ys) 141 | XCTAssertEqual(xs, ["b": "demo", "a": "test"]) 142 | XCTAssertEqual(xs.rawValue, ["b": "demo", "a": "test"]) 143 | } 144 | 145 | func testDictionary() { 146 | let nonEmptyDict1 = NonEmpty(("1", "Blob"), ["1": "Blobbo"], uniquingKeysWith: { $1 }) 147 | XCTAssertEqual(1, nonEmptyDict1.count) 148 | XCTAssertEqual("Blobbo", nonEmptyDict1["1"]) 149 | XCTAssertEqual( 150 | "Blob", NonEmpty(("1", "Blob"), ["1": "Blobbo"], uniquingKeysWith: { v, _ in v })["1"]) 151 | 152 | let nonEmptySingleton1 = NonEmptyDictionary((key: "1", value: "Blob")) 153 | XCTAssertEqual(1, nonEmptySingleton1.count) 154 | 155 | XCTAssert( 156 | NonEmpty<[String: String]>(("1", "Blob"), ["2": "Blob Senior"]) 157 | .merging(["2": "Blob Junior"], uniquingKeysWith: { $1 }) 158 | == NonEmpty(("1", "Blob"), ["2": "Blob Junior"]) 159 | ) 160 | XCTAssert( 161 | NonEmpty<[String: String]>(("1", "Blob"), ["2": "Blob Senior"]) 162 | .merging(["2": "Blob Junior"], uniquingKeysWith: { a, _ in a }) 163 | == NonEmpty(("1", "Blob"), ["2": "Blob Senior"]) 164 | ) 165 | } 166 | 167 | func testEquatable() { 168 | XCTAssertEqual(NonEmptyArray(1, 2, 3), NonEmptyArray(1, 2, 3)) 169 | XCTAssertNotEqual(NonEmptyArray(1, 2, 3), NonEmptyArray(2, 2, 3)) 170 | XCTAssertNotEqual(NonEmptyArray(1, 2, 3), NonEmptyArray(1, 2, 4)) 171 | XCTAssertEqual(NonEmptySet(1, 2, 3), NonEmptySet(3, 2, 1)) 172 | XCTAssert( 173 | NonEmpty(("hello", "world"), ["goodnight": "moon"]) 174 | == NonEmpty(("goodnight", "moon"), ["hello": "world"]) 175 | ) 176 | } 177 | 178 | func testComparable() { 179 | XCTAssertEqual(2, NonEmptyArray(1, 2, 3).min() + 1) 180 | XCTAssertEqual(2, NonEmptyArray(3, 2, 1).min() + 1) 181 | XCTAssertEqual(2, NonEmptyArray(1).min() + 1) 182 | XCTAssertEqual(4, NonEmptyArray(1, 2, 3).max() + 1) 183 | XCTAssertEqual(4, NonEmptyArray(3, 2, 1).max() + 1) 184 | XCTAssertEqual(4, NonEmptyArray(3).max() + 1) 185 | XCTAssertEqual(NonEmptyArray(1, 2, 3), NonEmptyArray(3, 1, 2).sorted()) 186 | XCTAssertEqual(NonEmptyArray(1), NonEmptyArray(1).sorted()) 187 | } 188 | 189 | func testCodable() throws { 190 | let xs = NonEmptyArray(1, 2, 3) 191 | XCTAssertEqual( 192 | xs, try JSONDecoder().decode(NonEmptyArray.self, from: JSONEncoder().encode(xs))) 193 | XCTAssertEqual( 194 | xs, try JSONDecoder().decode(NonEmptyArray.self, from: Data("[1,2,3]".utf8))) 195 | XCTAssertThrowsError(try JSONDecoder().decode(NonEmptyArray.self, from: Data("[]".utf8))) 196 | 197 | let str = NonEmptyString(rawValue: "Hello")! 198 | XCTAssertEqual( 199 | [str], try JSONDecoder().decode([NonEmptyString].self, from: JSONEncoder().encode([str]))) 200 | XCTAssertEqual( 201 | [str], try JSONDecoder().decode([NonEmptyString].self, from: Data(#"["Hello"]"#.utf8))) 202 | XCTAssertThrowsError(try JSONDecoder().decode([NonEmptyString].self, from: Data(#"[""]"#.utf8))) 203 | 204 | let dict = NonEmpty(rawValue: ["Hello": 1])! 205 | XCTAssertEqual( 206 | dict, try JSONDecoder().decode(NonEmpty<[String: Int]>.self, from: JSONEncoder().encode(dict)) 207 | ) 208 | XCTAssertEqual( 209 | dict, try JSONDecoder().decode(NonEmpty<[String: Int]>.self, from: Data(#"{"Hello":1}"#.utf8)) 210 | ) 211 | XCTAssertThrowsError( 212 | try JSONDecoder().decode(NonEmpty<[String: Int]>.self, from: Data("{}".utf8))) 213 | 214 | let data = NonEmpty(rawValue: Data("Hello".utf8)) 215 | XCTAssertEqual( 216 | data, try JSONDecoder().decode(NonEmpty.self, from: JSONEncoder().encode(data))) 217 | XCTAssertEqual( 218 | data, try JSONDecoder().decode(NonEmpty.self, from: Data(#""SGVsbG8=""#.utf8))) 219 | XCTAssertThrowsError(try JSONDecoder().decode(NonEmpty.self, from: Data("\"\"".utf8))) 220 | } 221 | 222 | func testNonEmptySetWithTrivialValue() { 223 | let xs = NonEmptySet(.init(value: 1), .init(value: 2)) 224 | let ys = NonEmptySet(.init(value: 2), .init(value: 1)) 225 | 226 | XCTAssertEqual(xs, ys) 227 | } 228 | 229 | func testMutableCollectionWithArraySlice() { 230 | let numbers = Array(1...10) 231 | var xs = NonEmpty(rawValue: numbers[5...])! 232 | xs[6] = 43 233 | XCTAssertEqual(43, xs[6]) 234 | } 235 | 236 | #if canImport(SwiftUI) 237 | func testMove() { 238 | var xs: NonEmptyArray = .init("A", "B", "C") 239 | xs.move(fromOffsets: [1], toOffset: 3) 240 | XCTAssertEqual(.init("A", "C", "B"), xs) 241 | } 242 | #endif 243 | } 244 | 245 | struct TrivialHashable: Equatable, Comparable, Hashable { 246 | let value: Int 247 | static func < (lhs: TrivialHashable, rhs: TrivialHashable) -> Bool { 248 | return lhs.value < rhs.value 249 | } 250 | func hash(into hasher: inout Hasher) { 251 | hasher.combine(self.value) 252 | } 253 | } 254 | --------------------------------------------------------------------------------