Add shared bark instance, tests, and documentation.

Author: rafcabezas

README.md

@@ -19,7 +19,7 @@ Bark is available through the Swift Package Manager. To install it, simply add t
 
 ```swift
 dependencies: [
-    .package(url: "https://github.com/willowtreeapps/bark.git", from: "1.0.1")
+    .package(url: "https://github.com/willowtreeapps/bark.git", from: "1.0.2")
 ]
 ```
 
@@ -31,7 +31,9 @@ Bark allows for structured concurrent message broadcasting. Here's an example fr
 ```swift
 // Bark instance: I recommend registering into dependency injection and resolving it where you need it.
 // Consider [Grove](https://github.com/willowtreeapps/grove) for this purpose!
-// You normally want a single instance of Bark for your app.
+// You normally want a single instance of Bark for your app, but you can define different instances that deal with different parts of the app.
+// The instance is similar in purpose to NotificationCenter instance.
+// If not using dependency injection, you can use `Bark.shared`. This is equivalent to NotificationCenter.default.
 let bark = Bark()
 
 func testPostsOfASingleSubscription() async throws {

Sources/Bark/Bark.swift

@@ -11,8 +11,10 @@ public final class Bark: @unchecked Sendable {
 
     // MARK: - Types
 
+    /// The block that is invoked when a subscription receives a notification
     public typealias Block = (Any?) async -> Void
 
+    /// Notifications are identified by their name
     public struct Name: Hashable, Equatable {
         private let value: String
         public init(_ value: String) {
@@ -22,6 +24,8 @@ public final class Bark: @unchecked Sendable {
         public var description: String { value }
     }
 
+    /// Subscriptions are scoped to a store. Create a store in a place where the store's lifetime will match when the subscription needs to be handled.
+    /// For example, you can create one Store per view (Make sure to mark it as @State if using SwiftUI)


     public final class Store: @unchecked Sendable {
         struct Handler {
             let name: Name
@@ -56,6 +60,7 @@ public final class Bark: @unchecked Sendable {
 
     // MARK: - Properties
 
+    public static let shared = Bark()
     private let lock = NSLock()
     private struct StoreWrapper {
         weak var store: Store?

Tests/BarkTests/BarkTests.swift

@@ -11,7 +11,7 @@ import XCTest
 
 final class BarkTests: XCTestCase {
     @MainActor
-    let bark = Bark()
+    let bark = Bark.shared
 
     @MainActor
     override func setUp() async throws {}