[fix-debounce]: should not send values repeatedly

Package.swift

@@ -107,8 +107,14 @@ extension Optional where Wrapped: RangeReplaceableCollection {
 import Foundation
 
 let env = ProcessInfo.processInfo.environment
-let key = "CX_COMBINE_IMPLEMENTATION"
-let combineImp = env[key].flatMap(CombineImplementation.init) ?? .default
+let impkey = "CX_COMBINE_IMPLEMENTATION"
+let isCIKey = "CX_CONTINUOUS_INTEGRATION"
+
+var combineImp = env[impkey].flatMap(CombineImplementation.init) ?? .default
+var isCI = env[isCIKey] != nil
+
+// uncommenet the following two lines if you want to test against combine
+//combineImp = .combine; isCI = true
 
 package.dependencies.append(contentsOf: combineImp.extraPackageDependencies)
 
@@ -120,7 +126,6 @@ for target in package.targets where target.isTest || target.name == "CXTestUtili
     target.swiftSettings.append(contentsOf: combineImp.swiftSettings)
 }
 
-if combineImp == .combine && env["CX_CONTINUOUS_INTEGRATION"] != nil {
+if combineImp == .combine && isCI {
     package.platforms = [.macOS("10.15"), .iOS("13.0"), .tvOS("13.0"), .watchOS("6.0")]
 }
-

Sources/CXTestUtility/TestScheduler.swift

@@ -93,7 +93,7 @@ public final class TestScheduler: Scheduler {
             self.lock.unlock()
         }
 
-        return box
+        return AnyCancellable(box)
     }
 
     public func advance(to time: SchedulerTimeType) {

Sources/CombineX/Publishers/D/Debounce.swift

@@ -119,6 +119,7 @@ extension Publishers.Debounce {
                     self.lock.unlock()
                     return
                 }
+                self.last = nil
                 self.demand -= 1
                 self.lock.unlock()
 

Tests/CombineXTests/Publishers/DebounceSpec.swift

@@ -58,9 +58,7 @@ class DebounceSpec: QuickSpec {
                 subject.send(1)
                 scheduler.advance(by: .seconds(10))
 
-                // FIXME: Strange
-                let expected = Array(repeating: TestSubscriberEvent<Int, TestError>.value(1), count: 10)
-                expect(sub.events).to(equal(expected))
+                expect(sub.events).to(equal([.value(1)]))
             }
 
             // MARK: 1.3 should send as many values as demand