initial commit

Package.swift

@@ -0,0 +1,23 @@
+// swift-tools-version:5.1
+
+import PackageDescription
+
+let package = Package(
+    name: "CombinePrintout",
+    platforms: [
+      .iOS(.v13),
+    ],
+    products: [
+        .library(
+            name: "CombinePrintout",
+            targets: ["CombinePrintout"]),
+    ],
+    targets: [
+        .target(
+            name: "CombinePrintout",
+            dependencies: []),
+        .testTarget(
+            name: "CombinePrintoutTests",
+            dependencies: ["CombinePrintout"]),
+    ]
+)

README.md

@@ -1,2 +1,62 @@
 # CombinePrintout
-A Combine micro debugging package
+
+A Combine micro debugging framework. It helps you log subscription events to the console so you can track their life cycle.
+
+## Usage
+
+#### A debugging print sink
+
+The built-in `print()` operator is useful but you still need to add a subscriber to your subscription. `printSink()` is a subscriber that you can use to debug a subscription without the need to add a separate subscriber like so:
+
+```swift
+Just(["One", "Two"])
+  .printSink()
+```
+
+`printSink()` will subscribe the publisher and log all events like so:
+
+```none
+Sink: output(["One", "Two"]) 
+Sink: finished
+```
+
+#### A debugging print cancellable
+
+If you're building more complex memory management logic or not sure when are your cancellables released you can use `printCancellable()` to log a given `Cancellable`'s life cycle like so:
+
+```swift
+Just(["One", "Two"])
+  .assign(to: \.model, on: self)
+  .printCancellable()
+  .store(in: &subscriptions)
+```
+
+`printCancellable()` wraps the `AnyCancellable` returned from `assign(to:on:)` and logs all the received events:
+
+```none
+Cancellable: init 
+... 
+(self.subscriptions is released from memory)
+...
+Cancellable: cancel 
+Cancellable: deinit 
+```
+
+## Installation
+
+### Swift Package Manager
+
+Add the following dependency to your **Package.swift** file:
+
+```swift
+.package(url: "https://github.com/combineopensource/CombinePrintout, from: "0.2")
+```
+## License
+
+CombineOpenSource is available under the MIT license. See the LICENSE file for more info.
+
+
+## Credit
+
+Copyright (c) 2019 Combine Open Source
+Created by: Marin Todorov

Sources/CombinePrintout/CombinePrintout.swift

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+import Combine
+
+class PrintCancellable: Cancellable {
+  let wrapped: AnyCancellable
+  let id: String
+
+  init(_ wrapped: AnyCancellable, id: String? = nil) {
+    self.wrapped = wrapped
+    self.id = id ?? ""
+    Swift.print("Cancellable: init \(self.id)")
+  }
+
+  func cancel() {
+    wrapped.cancel()
+    Swift.print("Cancellable: cancel \(id)")
+  }
+
+  deinit {
+    Swift.print("Cancellable: deinit \(id)")
+  }
+}
+
+extension Cancellable {
+
+  /// A debugging `Cancellable` wrapper that prints out `Cancellable` life cycle events.
+  /// - Parameter id: An optional identifier to print along the output.
+  public func printCancellable(id: String? = nil) -> AnyCancellable {
+    return AnyCancellable(PrintCancellable(AnyCancellable(self), id: id))
+  }
+}
+
+extension Publisher {
+
+  /// A debugging sink that prints all received events.
+  /// - Parameter id: An optional identifier to print along the output.
+  public func printSink(id: String = "") -> AnyCancellable {
+    return sink(receiveCompletion: { Swift.print("Sink: \($0) \(id)") },
+                receiveValue: { Swift.print("Sink: output(\($0)) \(id)") })
+  }
+}

Tests/CombinePrintoutTests/CombinePrintoutTests.swift

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+import XCTest
+@testable import CombinePrintout
+
+final class CombinePrintoutTests: XCTestCase {
+    func testExample() {
+        // This is an example of a functional test case.
+        // Use XCTAssert and related functions to verify your tests produce the correct
+        // results.
+        XCTAssertEqual(CombinePrintout().text, "Hello, World!")
+    }
+
+    static var allTests = [
+        ("testExample", testExample),
+    ]
+}

Tests/CombinePrintoutTests/XCTestManifests.swift

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+import XCTest
+
+#if !canImport(ObjectiveC)
+public func allTests() -> [XCTestCaseEntry] {
+    return [
+        testCase(CombinePrintoutTests.allTests),
+    ]
+}
+#endif

Tests/LinuxMain.swift

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+import XCTest
+
+import CombinePrintoutTests
+
+var tests = [XCTestCaseEntry]()
+tests += CombinePrintoutTests.allTests()
+XCTMain(tests)