Slightly nicer string description for Signal (#42)

* Slightly nicer string description for Signal
* compat with swift before 5.3

Author: ktoso

Sources/Lifecycle/Lifecycle.swift

@@ -161,13 +161,25 @@ extension ServiceLifecycle {
     }
 
     /// A system signal
-    public struct Signal {
+    public struct Signal: Equatable, CustomStringConvertible {
         internal var rawValue: CInt
 
-        public static let TERM: Signal = Signal(rawValue: SIGTERM)
-        public static let INT: Signal = Signal(rawValue: SIGINT)
+        public static let TERM = Signal(rawValue: SIGTERM)
+        public static let INT = Signal(rawValue: SIGINT)
         // for testing
-        internal static let ALRM: Signal = Signal(rawValue: SIGALRM)
+        internal static let ALRM = Signal(rawValue: SIGALRM)
+
+        public var description: String {
+            var result = "Signal("
+            switch self {
+            case Signal.TERM: result += "TERM, "
+            case Signal.INT: result += "INT, "
+            case Signal.ALRM: result += "ALRM, "
+            default: () // ok to ignore
+            }
+            result += "rawValue: \(self.rawValue))"
+            return result
+        }
     }
 }
 

Tests/LifecycleTests/ServiceLifecycleTests+XCTest.swift

@@ -31,6 +31,7 @@ extension ServiceLifecycleTests {
             ("testBadStartAndWait", testBadStartAndWait),
             ("testNesting", testNesting),
             ("testNesting2", testNesting2),
+            ("testSignalDescription", testSignalDescription),
         ]
     }
 }

Tests/LifecycleTests/ServiceLifecycleTests.swift

@@ -171,4 +171,10 @@ final class ServiceLifecycleTests: XCTestCase {
         lifecycle.wait()
         subsystem.subsystem.items.forEach { XCTAssertEqual($0.state, .shutdown, "expected item to be shutdown, but \($0.state)") }
     }
+
+    func testSignalDescription() {
+        XCTAssertEqual("\(ServiceLifecycle.Signal.TERM)", "Signal(TERM, rawValue: \(ServiceLifecycle.Signal.TERM.rawValue))")
+        XCTAssertEqual("\(ServiceLifecycle.Signal.INT)", "Signal(INT, rawValue: \(ServiceLifecycle.Signal.INT.rawValue))")
+        XCTAssertEqual("\(ServiceLifecycle.Signal.ALRM)", "Signal(ALRM, rawValue: \(ServiceLifecycle.Signal.ALRM.rawValue))")
+    }
 }