feat: add uuid validation rule

Author: ns-vasilev

README.md

@@ -318,6 +318,7 @@ struct RegistrationView: View {
 | `IPAddressValidationRule` | Validates that a string is a valid IPv4 or IPv6 address | `IPAddressValidationRule(version: .v4, error: ValidationError("Invalid IPv4"))`
 | `PostalCodeValidationRule` | Validates postal/ZIP codes for different countries | `PostalCodeValidationRule(country: .uk, error: "Invalid post code")`
 | `Base64ValidationRule` | | `Base64ValidationRule(error: "The input is not valid Base64.")`
+| `UUIDValidationRule` | Validates UUID format | `UUIDValidationRule(error: "Please enter a valid UUID")` |
 
 ## Custom Validators
 

Sources/ValidatorCore/Classes/Rules/URLValidationRule.swift

@@ -5,15 +5,14 @@
 
 import Foundation
 
-// Validates that a string represents a valid URL.
-//
-// # Example:
-// ```swift
-// let rule = URLValidationRule(error: "Invalid URL")
-// rule.validate(input: "https://example.com") // true
-// rule.validate(input: "not_a_url") // false
-// ```
-
+/// Validates that a string represents a valid URL.
+///
+/// # Example:
+/// ```swift
+/// let rule = URLValidationRule(error: "Invalid URL")
+/// rule.validate(input: "https://example.com") // true
+/// rule.validate(input: "not_a_url") // false
+/// ```
 public struct URLValidationRule: IValidationRule {
     // MARK: Types
 

Sources/ValidatorCore/Classes/Rules/UUIDValidationRule.swift

@@ -0,0 +1,40 @@
+//
+// Validator
+// Copyright © 2026 Space Code. All rights reserved.
+//
+
+import Foundation
+
+/// Validates that a string represents a valid UUID.
+///
+/// # Example:
+/// ```swift
+/// let rule = UUIDValidationRule(error: "Invalid UUID")
+/// rule.validate(input: "47273ec2-e638-4702-8325-dcf82ed6a95b") // true
+/// rule.validate(input: "47273ec2") // false
+/// ```
+public struct UUIDValidationRule: IValidationRule {
+    // MARK: Types
+
+    public typealias Input = String
+
+    // MARK: Properties
+
+    /// The validation error returned if the input is not a valid UUID.
+    public let error: IValidationError
+
+    // MARK: Initialization
+
+    /// Initializes a URL validation rule.
+    ///
+    /// - Parameter error: The validation error returned if input fails validation.
+    public init(error: IValidationError) {
+        self.error = error
+    }
+
+    // MARK: IValidationRule
+
+    public func validate(input: String) -> Bool {
+        UUID(uuidString: input) != nil
+    }
+}

Sources/ValidatorCore/Validator.docc/Overview.md

@@ -41,6 +41,7 @@ ValidatorCore contains all core validation rules, utilities, and mechanisms for
 - ``IPAddressValidationRule``
 - ``PostalCodeValidationRule``
 - ``Base64ValidationRule``
+- ``UUIDValidationRule``
 
 ### Articles
 

Tests/ValidatorCoreTests/UnitTests/Rules/UUIDValidationRuleTests.swift

@@ -0,0 +1,79 @@
+//
+// Validator
+// Copyright © 2026 Space Code. All rights reserved.
+//
+
+import ValidatorCore
+import XCTest
+
+// MARK: - UUIDValidationRuleTests
+
+final class UUIDValidationRuleTests: XCTestCase {
+    // MARK: - Properties
+
+    private var sut: UUIDValidationRule!
+
+    // MARK: - Setup
+
+    override func setUp() {
+        super.setUp()
+        sut = UUIDValidationRule(error: String.error)
+    }
+
+    override func tearDown() {
+        sut = nil
+        super.tearDown()
+    }
+
+    // MARK: Tests
+
+    func test_validate_validUUID_shouldReturnTrue() {
+        // given
+        let uuid = "550e8400-e29b-41d4-a716-446655440000"
+
+        // when
+        let result = sut.validate(input: uuid)
+
+        // then
+        XCTAssertTrue(result)
+    }
+
+    func test_validate_emptyString_shouldReturnFalse() {
+        // given
+        let uuid = ""
+
+        // when
+        let result = sut.validate(input: uuid)
+
+        // then
+        XCTAssertFalse(result)
+    }
+
+    func test_validate_whitespaceString_shouldReturnFalse() {
+        // given
+        let uuid = "    "
+
+        // when
+        let result = sut.validate(input: uuid)
+
+        // then
+        XCTAssertFalse(result)
+    }
+
+    func test_validate_invalidUUID_shouldReturnFalse() {
+        // given
+        let uuid = "not-a-uuid"
+
+        // when
+        let result = sut.validate(input: uuid)
+
+        // then
+        XCTAssertFalse(result)
+    }
+}
+
+// MARK: Constants
+
+private extension String {
+    static let error = "UUID is invalid"
+}