Fix covariance

src/Cache/ArrayResult.php

@@ -74,6 +74,7 @@ public function fetchFirstColumn(): array
         return FetchUtils::fetchFirstColumn($this);
     }
 
+    /** @return non-negative-int */
     public function rowCount(): int
     {
         return count($this->data);

src/Connection.php

@@ -880,7 +880,7 @@ public function getTransactionNestingLevel(): int
      *
      * If the underlying driver does not support identity columns, an exception is thrown.
      *
-     * @return non-negative-int|numeric-string The last insert ID, as an integer or a numeric string.
+     * @return int|numeric-string The last insert ID, as an integer or a numeric string.
      *
      * @throws Exception
      */

src/Driver/IBMDB2/Connection.php

@@ -66,6 +66,7 @@ public function quote(string $value): string
         return "'" . db2_escape_string($value) . "'";
     }
 
+    /** @return non-negative-int */
     public function exec(string $sql): int
     {
         $stmt = @db2_exec($this->connection, $sql);

src/Driver/IBMDB2/Result.php

@@ -77,6 +77,7 @@ public function fetchFirstColumn(): array
         return FetchUtils::fetchFirstColumn($this);
     }
 
+    /** @return non-negative-int */
     public function rowCount(): int
     {
         return @db2_num_rows($this->statement);

src/Driver/OCI8/Connection.php

@@ -75,6 +75,8 @@ public function quote(string $value): string
     }
 
     /**
+     * @return non-negative-int
+     *
      * @throws Exception
      * @throws Parser\Exception
      */

src/Driver/OCI8/Result.php

@@ -73,6 +73,7 @@ public function fetchFirstColumn(): array
         return $this->fetchAll(OCI_NUM, OCI_FETCHSTATEMENT_BY_COLUMN)[0];
     }
 
+    /** @return non-negative-int */
     public function rowCount(): int
     {
         $count = oci_num_rows($this->statement);

src/Driver/PDO/Connection.php

@@ -21,6 +21,7 @@ public function __construct(private readonly PDO $connection)
         $connection->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
     }
 
+    /** @return non-negative-int */
     public function exec(string $sql): int
     {
         try {

src/Driver/PDO/Result.php

@@ -55,6 +55,7 @@ public function fetchFirstColumn(): array
         return $this->fetchAll(PDO::FETCH_COLUMN);
     }
 
+    /** @return non-negative-int */
     public function rowCount(): int
     {
         try {

src/Driver/PgSQL/Connection.php

@@ -83,6 +83,7 @@ public function quote(string $value): string
         return $quotedValue;
     }
 
+    /** @return non-negative-int */
     public function exec(string $sql): int
     {
         return $this->query($sql)->rowCount();

src/Driver/PgSQL/Result.php

@@ -118,6 +118,7 @@ public function fetchFirstColumn(): array
         );
     }
 
+    /** @return non-negative-int */
     public function rowCount(): int
     {
         if ($this->result === null) {

src/Driver/SQLSrv/Connection.php

@@ -49,6 +49,7 @@ public function quote(string $value): string
         return "'" . str_replace("'", "''", $value) . "'";
     }
 
+    /** @return non-negative-int */
     public function exec(string $sql): int
     {
         $stmt = sqlsrv_query($this->connection, $sql);

src/Driver/SQLSrv/Result.php

@@ -65,6 +65,7 @@ public function fetchFirstColumn(): array
         return FetchUtils::fetchFirstColumn($this);
     }
 
+    /** @return non-negative-int */
     public function rowCount(): int
     {
         $count = sqlsrv_rows_affected($this->statement);

src/Driver/SQLite3/Connection.php

@@ -49,6 +49,7 @@ public function quote(string $value): string
         return sprintf('\'%s\'', SQLite3::escapeString($value));
     }
 
+    /** @return non-negative-int */
     public function exec(string $sql): int
     {
         try {

src/Driver/SQLite3/Result.php

@@ -62,6 +62,7 @@ public function fetchFirstColumn(): array
         return FetchUtils::fetchFirstColumn($this);
     }
 
+    /** @return non-negative-int */
     public function rowCount(): int
     {
         return $this->changes;