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NachoSotoNachoSoto
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Add take(until:) operator (#839)
Forward any values until `shouldContinue` returns `false`, at which point the returned signal forwards the last value and then it completes. This is equivalent to `take(while:)`, except it also forwards the last value that failed the check.
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‎CHANGELOG.md

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@@ -26,6 +26,8 @@
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When debugging your application, the call stacks involving ReactiveSwift may now look cleaner, without the clutter of compiler-generated reabstraction thunks. See #799 for an example.
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1. New operator `SignalProducer.take(until:)` that forwards any values until `shouldContinue` returns `false`. Equivalent to `take(while:)`, except it also forwards the last value that failed the check. (#839, kudos to @nachosoto)
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# 6.6.1
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1. Updated Carthage xcconfig dependency to 1.1 for proper building arm64 macOS variants. (#826, kudos to @MikeChugunov)
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‎ReactiveSwift.xcodeproj/project.pbxproj

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@@ -19,6 +19,10 @@
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4A0E11041D2A95200065D310 /* LifetimeSpec.swift in Sources */ = {isa = PBXBuildFile; fileRef = 4A0E11031D2A95200065D310 /* LifetimeSpec.swift */; };
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4A0E11051D2A95200065D310 /* LifetimeSpec.swift in Sources */ = {isa = PBXBuildFile; fileRef = 4A0E11031D2A95200065D310 /* LifetimeSpec.swift */; };
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4A0E11061D2A95200065D310 /* LifetimeSpec.swift in Sources */ = {isa = PBXBuildFile; fileRef = 4A0E11031D2A95200065D310 /* LifetimeSpec.swift */; };
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5792972826DE7623007A9F64 /* TakeUntil.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5792972726DE7623007A9F64 /* TakeUntil.swift */; };
23+
5792972926DE7623007A9F64 /* TakeUntil.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5792972726DE7623007A9F64 /* TakeUntil.swift */; };
24+
5792972A26DE7623007A9F64 /* TakeUntil.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5792972726DE7623007A9F64 /* TakeUntil.swift */; };
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5792972B26DE7623007A9F64 /* TakeUntil.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5792972726DE7623007A9F64 /* TakeUntil.swift */; };
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579504331BB8A34200A5E482 /* BagSpec.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0C312EF19EF2A7700984962 /* BagSpec.swift */; };
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579504341BB8A34300A5E482 /* BagSpec.swift in Sources */ = {isa = PBXBuildFile; fileRef = D0C312EF19EF2A7700984962 /* BagSpec.swift */; };
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57A4D1B11BA13D7A00F7D4B1 /* Optional.swift in Sources */ = {isa = PBXBuildFile; fileRef = D871D69E1B3B29A40070F16C /* Optional.swift */; };
@@ -393,6 +397,7 @@
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4A0AB6711DC28EFF00AA1E81 /* ReactiveExtensionsSpec.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = ReactiveExtensionsSpec.swift; sourceTree = "<group>"; };
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4A0E10FE1D2A92720065D310 /* Lifetime.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Lifetime.swift; sourceTree = "<group>"; };
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4A0E11031D2A95200065D310 /* LifetimeSpec.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = LifetimeSpec.swift; sourceTree = "<group>"; };
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5792972726DE7623007A9F64 /* TakeUntil.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = TakeUntil.swift; sourceTree = "<group>"; };
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57A4D2411BA13D7A00F7D4B1 /* ReactiveSwift.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = ReactiveSwift.framework; sourceTree = BUILT_PRODUCTS_DIR; };
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57A4D2441BA13F9700F7D4B1 /* tvOS-Application.xcconfig */ = {isa = PBXFileReference; lastKnownFileType = text.xcconfig; path = "tvOS-Application.xcconfig"; sourceTree = "<group>"; };
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57A4D2451BA13F9700F7D4B1 /* tvOS-Base.xcconfig */ = {isa = PBXFileReference; lastKnownFileType = text.xcconfig; path = "tvOS-Base.xcconfig"; sourceTree = "<group>"; };
@@ -578,6 +583,7 @@
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9A2D5C9E259F8059005682ED /* TakeFirst.swift */,
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9A2D5CAD259F8112005682ED /* TakeLast.swift */,
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9A2D5CB7259F8199005682ED /* TakeWhile.swift */,
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5792972726DE7623007A9F64 /* TakeUntil.swift */,
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9A2D5CC1259F81FC005682ED /* SkipFirst.swift */,
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9A2D5CCB259F8263005682ED /* SkipWhile.swift */,
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9A2D5C4E259F7B21005682ED /* MapError.swift */,
@@ -1051,6 +1057,7 @@
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57A4D1B81BA13D7A00F7D4B1 /* Scheduler.swift in Sources */,
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9A9100E21E0E6E680093E346 /* ValidatingProperty.swift in Sources */,
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9A2D5CF2259F85AE005682ED /* SkipRepeats.swift in Sources */,
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5792972B26DE7623007A9F64 /* TakeUntil.swift in Sources */,
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9A2D5CBB259F8199005682ED /* TakeWhile.swift in Sources */,
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57A4D1B91BA13D7A00F7D4B1 /* Action.swift in Sources */,
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57A4D1BA1BA13D7A00F7D4B1 /* Property.swift in Sources */,
@@ -1153,6 +1160,7 @@
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9AFA491324E9A196003D263C /* Map.swift in Sources */,
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9A2D5CFB259F8634005682ED /* UniqueValues.swift in Sources */,
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9A2D5C65259F7B47005682ED /* MaterializeAsResult.swift in Sources */,
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5792972A26DE7623007A9F64 /* TakeUntil.swift in Sources */,
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9A2D5D55259FA000005682ED /* Throttle.swift in Sources */,
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9A67963D1F6059430058C5B4 /* UninhabitedTypeGuards.swift in Sources */,
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9A2D5D5F259FA0DD005682ED /* Debounce.swift in Sources */,
@@ -1196,6 +1204,7 @@
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9A9100DF1E0E6E620093E346 /* ValidatingProperty.swift in Sources */,
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EBCC7DBC1BBF010C00A2AE92 /* Signal.Observer.swift in Sources */,
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9A2D5CEF259F85AE005682ED /* SkipRepeats.swift in Sources */,
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5792972826DE7623007A9F64 /* TakeUntil.swift in Sources */,
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9A2D5CB8259F8199005682ED /* TakeWhile.swift in Sources */,
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D03B4A3D19F4C39A009E02AC /* FoundationExtensions.swift in Sources */,
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9A090C141DA0309E00EE97CA /* Reactive.swift in Sources */,
@@ -1298,6 +1307,7 @@
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9AFA491224E9A196003D263C /* Map.swift in Sources */,
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9A2D5CFA259F8634005682ED /* UniqueValues.swift in Sources */,
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9A2D5C64259F7B47005682ED /* MaterializeAsResult.swift in Sources */,
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5792972926DE7623007A9F64 /* TakeUntil.swift in Sources */,
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9A2D5D54259FA000005682ED /* Throttle.swift in Sources */,
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9A67963C1F6059420058C5B4 /* UninhabitedTypeGuards.swift in Sources */,
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9A2D5D5E259FA0DD005682ED /* Debounce.swift in Sources */,

‎Sources/Event.swift

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@@ -290,6 +290,12 @@ extension Signal.Event {
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Operators.TakeWhile(downstream: downstream, shouldContinue: shouldContinue)
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}
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}
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internal static func take(until shouldContinue: @escaping (Value) -> Bool) -> Transformation<Value, Error> {
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return { downstream, _ in
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Operators.TakeUntil(downstream: downstream, shouldContinue: shouldContinue)
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}
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}
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internal static func skip(first count: Int) -> Transformation<Value, Error> {
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return { downstream, _ in

‎Sources/Observers/TakeUntil.swift

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extension Operators {
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internal final class TakeUntil<Value, Error: Swift.Error>: Observer<Value, Error> {
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let downstream: Observer<Value, Error>
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let shouldContinue: (Value) -> Bool
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init(downstream: Observer<Value, Error>, shouldContinue: @escaping (Value) -> Bool) {
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self.downstream = downstream
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self.shouldContinue = shouldContinue
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}
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override func receive(_ value: Value) {
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downstream.receive(value)
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if !shouldContinue(value) {
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downstream.terminate(.completed)
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}
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}
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override func terminate(_ termination: Termination<Error>) {
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downstream.terminate(termination)
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}
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}
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}

‎Sources/Signal.swift

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@@ -1595,9 +1595,23 @@ extension Signal {
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/// continue.
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///
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/// - returns: A signal which conditionally forwards values from `self`.
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/// - seealso: `take(until:)`
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public func take(while shouldContinue: @escaping (Value) -> Bool) -> Signal<Value, Error> {
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return flatMapEvent(Signal.Event.take(while: shouldContinue))
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}
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/// Forward any values from `self` until `shouldContinue` returns `false`, at which
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/// point the returned signal forwards the last value and then it completes.
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/// This is equivalent to `take(while:)`, except it also forwards the last value that failed the check.
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///
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/// - parameters:
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/// - shouldContinue: A closure to determine whether the forwarding of values should
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/// continue.
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///
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/// - returns: A signal which conditionally forwards values from `self`.
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public func take(until shouldContinue: @escaping (Value) -> Bool) -> Signal<Value, Error> {
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return flatMapEvent(Signal.Event.take(until: shouldContinue))
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}
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}
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extension Signal {

‎Sources/SignalProducer.swift

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@@ -1630,6 +1630,19 @@ extension SignalProducer {
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return core.flatMapEvent(Signal.Event.take(last: count))
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}
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/// Forward any values from `self` until `shouldContinue` returns `false`, at which
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/// point the returned signal forwards the last value and then it completes.
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/// This is equivalent to `take(while:)`, except it also forwards the last value that failed the check.
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///
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/// - parameters:
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/// - shouldContinue: A closure to determine whether the forwarding of values should
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/// continue.
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///
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/// - returns: A signal which conditionally forwards values from `self`.
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public func take(until shouldContinue: @escaping (Value) -> Bool) -> SignalProducer<Value, Error> {
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return core.flatMapEvent(Signal.Event.take(until: shouldContinue))
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}
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/// Forward any values from `self` until `shouldContinue` returns `false`, at which
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/// point the produced `Signal` would complete.
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///

‎Tests/ReactiveSwiftTests/SignalProducerLiftingSpec.swift

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@@ -1148,7 +1148,7 @@ class SignalProducerLiftingSpec: QuickSpec {
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beforeEach {
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let (baseProducer, incomingObserver) = SignalProducer<Int, Never>.pipe()
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producer = baseProducer.take { $0 <= 4 }
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producer = baseProducer.take(while: { $0 <= 4 })
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observer = incomingObserver
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}
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expect(completed) == true
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}
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}
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describe("takeUntil") {
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var producer: SignalProducer<Int, Never>!
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var observer: Signal<Int, Never>.Observer!
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beforeEach {
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let (baseProducer, incomingObserver) = SignalProducer<Int, Never>.pipe()
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producer = baseProducer.take(until: { $0 <= 4 })
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observer = incomingObserver
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}
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it("should take until the predicate is true") {
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var latestValue: Int!
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var completed = false
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producer.start { event in
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switch event {
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case let .value(value):
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latestValue = value
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case .completed:
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completed = true
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case .failed, .interrupted:
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break
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}
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}
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for value in -1...4 {
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observer.send(value: value)
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expect(latestValue) == value
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expect(completed) == false
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}
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observer.send(value: 5)
1234+
expect(latestValue) == 5
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expect(completed) == true
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observer.send(value: 6)
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expect(latestValue) == 5
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}
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it("should take and then complete if the predicate starts false") {
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var latestValue: Int?
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var completed = false
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producer.start { event in
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switch event {
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case let .value(value):
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latestValue = value
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case .completed:
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completed = true
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case .failed, .interrupted:
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break
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}
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}
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observer.send(value: 5)
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expect(latestValue) == 5
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expect(completed) == true
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}
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}
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12021262
describe("observeOn") {
12031263
it("should send events on the given scheduler") {

‎Tests/ReactiveSwiftTests/SignalSpec.swift

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@@ -1644,7 +1644,7 @@ class SignalSpec: QuickSpec {
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beforeEach {
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let (baseSignal, incomingObserver) = Signal<Int, Never>.pipe()
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signal = baseSignal.take { $0 <= 4 }
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signal = baseSignal.take(while: { $0 <= 4 })
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observer = incomingObserver
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}
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expect(completed) == true
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}
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}
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describe("takeUntil") {
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var signal: Signal<Int, Never>!
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var observer: Signal<Int, Never>.Observer!
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1702+
beforeEach {
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let (baseSignal, incomingObserver) = Signal<Int, Never>.pipe()
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signal = baseSignal.take(until: { $0 <= 4 })
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observer = incomingObserver
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}
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1708+
it("should take until the predicate is true") {
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var latestValue: Int!
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var completed = false
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signal.observe { event in
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switch event {
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case let .value(value):
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latestValue = value
1716+
case .completed:
1717+
completed = true
1718+
default:
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break
1720+
}
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}
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for value in -1...4 {
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observer.send(value: value)
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expect(latestValue) == value
1726+
expect(completed) == false
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}
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observer.send(value: 5)
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expect(latestValue) == 5
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expect(completed) == true
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1733+
observer.send(value: 6)
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expect(latestValue) == 5
1735+
}
1736+
1737+
it("should take and then complete if the predicate starts false") {
1738+
var latestValue: Int?
1739+
var completed = false
1740+
1741+
signal.observe { event in
1742+
switch event {
1743+
case let .value(value):
1744+
latestValue = value
1745+
case .completed:
1746+
completed = true
1747+
default:
1748+
break
1749+
}
1750+
}
1751+
1752+
observer.send(value: 5)
1753+
expect(latestValue) == 5
1754+
expect(completed) == true
1755+
}
1756+
}
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16981758
describe("observeOn") {
16991759
it("should send events on the given scheduler") {

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