Enhance constructor error message in case the default value is missing (

#31)

* Enhance constructor error message in case the default value is missing

* Delete unneeded overriden functions in test cases

Sources/PDefaults/PDefaults+Init.swift

@@ -155,7 +155,7 @@ public extension PDefaults {
     }
 
     /// Constructor catching all type errors to expose compatibility constraints message
-    @available(*, unavailable, message: "You can use PDefaults only types that either conform to Codable or are natively handled by UserDefaults")
+    @available(*, unavailable, message: "You have to provide a default value or use an optional type. In the latter case, make sure the type either conforms to Codable or is natively handled by UserDefaults")
     // swiftlint:disable:previous line_length
     convenience init(_ key: String,
                      suite: UserDefaults = .standard,

Tests/PDefaultsTests/TestMigration.swift

@@ -17,10 +17,6 @@ class TestMigration: XCTestCase {
         PDefaultsConfiguration.mock = false
     }
 
-    override func tearDown() {
-        super.tearDown()
-    }
-
     func testNominalMigration() {
         let value = 1
         let source = PDefaults<Int?>(wrappedValue: nil, sourceKey)

Tests/PDefaultsTests/TestPublisher.swift

@@ -13,10 +13,6 @@ class TestPublisher: XCTestCase {
         PDefaultsConfiguration.mock = false
     }
 
-    override func tearDown() {
-        super.tearDown()
-    }
-
     func testClosureCalledOnSink() {
         let pdefaults = PDefaults(wrappedValue: 1, key, suite: suite)
         let expectCalled = expectation(description: "PDefaults publisher sink closure is expected to be called on"

Tests/PDefaultsTests/TestStorage.swift

@@ -13,10 +13,6 @@ class TestStorage: XCTestCase {
         PDefaultsConfiguration.mock = false
     }
 
-    override func tearDown() {
-        super.tearDown()
-    }
-
     func testNoStorageWhenNotNeeded() {
         let pDefaults = PDefaults(wrappedValue: Optional.some(1), key, suite: suite)
         XCTAssert(suite.object(forKey: key) == nil, "Storage should not contain a value for key \"\(key)\"")