Defined the Randomable protocol in the library target.

Library/Sources/Internal/Protocols/Randomable.swift

@@ -0,0 +1,7 @@
+protocol Randomable: CaseIterable {
+    
+    // MARK: Functions
+    
+    static func random() -> Self
+    
+}

Test/Sources/Cases/Internal/Protocols/RandomableTests.swift

@@ -0,0 +1,32 @@
+import Testing
+
+@testable import ColibriLibrary
+
+struct RandomableTest {
+
+    @Test func random() {
+        // GIVEN
+        let allCases = TestRandomable.allCases
+
+        // WHEN
+        let random = TestRandomable.random()
+        
+        // THEN
+        #expect(allCases.contains(random))
+    }
+
+}
+
+// MARK: - Enumerations
+
+enum TestRandomable: Randomable {
+    case someCase
+    case someOtherCase
+
+    // MARK: Functions
+    
+    static func random() -> TestRandomable {
+        .allCases.randomElement() ?? .someCase
+    }
+    
+}