[Password] mark password functions pure

src/Psl/Password/algorithms.php

@@ -8,6 +8,8 @@ namespace Psl\Password;
  * Return a complete list of all registered password hashing algorithms.
  *
  * @psalm-return list<string>
+ *
+ * @psalm-pure
  */
 function algorithms(): array
 {

src/Psl/Password/get_information.php

@@ -18,6 +18,8 @@ use function password_get_info;
  *      algorithm: string,
  *      options: array{cost: int}|array{memory_cost: int, time_cost: int, threads: int}
  * }
+ *
+ * @psalm-pure
  */
 function get_information(string $hash): array
 {

src/Psl/Password/hash.php

@@ -26,6 +26,8 @@ use const PASSWORD_BCRYPT;
  * @see ARGON2I_ALGORITHM for the argon2i, and argon2id supported options.
  *
  * @throws Psl\Exception\InvariantViolationException The given algorithm is unsupported.
+ *
+ * @psalm-pure
  */
 function hash(string $password, string $algorithm = DEFAULT_ALGORITHM, array $options = []): string
 {

src/Psl/Password/needs_rehash.php

@@ -19,6 +19,8 @@ use function password_needs_rehash;
  * This function is safe against timing attacks.
  *
  * @psalm-param array{cost?: int}|array{memory_cost?: int, time_cost?: int, threads?: int} $options
+ *
+ * @psalm-pure
  */
 function needs_rehash(string $hash, string $algorithm = DEFAULT_ALGORITHM, array $options = []): bool
 {

src/Psl/Password/verify.php

@@ -8,6 +8,8 @@ use function password_verify;
 
 /**
  * Checks if the given hash matches the given options.
+ *
+ * @psalm-pure
  */
 function verify(string $password, string $hash): bool
 {