fixes for PHP 8.0

.phpstan.neon

@@ -14,6 +14,8 @@ parameters:
 		Nextras\Dbal\Drivers\Sqlsrv\SqlsrvDriver:
 			- throwErrors
 
+	reportUnmatchedIgnoredErrors: false
+
 	ignoreErrors:
 		-
 			message: '~Call to an undefined method .+::children\(\)\.~'

src/Drivers/Mysqli/MysqliDriver.php

@@ -101,8 +101,7 @@ public function connect(array $params, ILogger $logger): void
 			throw $this->createException(
 				$this->connection->connect_error ?? $this->connection->error, // @phpstan-ignore-line
 				$this->connection->connect_errno,
-				// @phpstan-ignore-next-line - Property access is not allowed yet
-				@$this->connection->sqlstate ?: 'HY000'
+				'HY000'
 			);
 		}
 
@@ -376,8 +375,10 @@ public function convertIdentifierToSql(string $value): string
 
 	public function convertDateTimeToSql(DateTimeInterface $value): string
 	{
+		$valueTimezone = $value->getTimezone();
 		assert($value instanceof DateTime || $value instanceof DateTimeImmutable);
-		if ($value->getTimezone()->getName() !== $this->connectionTz->getName()) {
+		assert($valueTimezone !== false); // @phpstan-ignore-line
+		if ($valueTimezone->getName() !== $this->connectionTz->getName()) {
 			if ($value instanceof DateTimeImmutable) {
 				$value = $value->setTimezone($this->connectionTz);
 			} else {

src/Drivers/Pgsql/PgsqlDriver.php

@@ -147,7 +147,7 @@ public function getResourceHandle()
 	public function query(string $query): Result
 	{
 		assert($this->connection !== null);
-		if (!pg_send_query($this->connection, $query)) {
+		if (pg_send_query($this->connection, $query) === false) {
 			throw $this->createException(pg_last_error($this->connection), 0, null);
 		}
 
@@ -344,8 +344,10 @@ public function convertIdentifierToSql(string $value): string
 
 	public function convertDateTimeToSql(DateTimeInterface $value): string
 	{
+		$valueTimezone = $value->getTimezone();
 		assert($value instanceof DateTime || $value instanceof DateTimeImmutable);
-		if ($value->getTimezone()->getName() !== $this->connectionTz->getName()) {
+		assert($valueTimezone !== false); // @phpstan-ignore-line
+		if ($valueTimezone->getName() !== $this->connectionTz->getName()) {
 			if ($value instanceof DateTimeImmutable) {
 				$value = $value->setTimezone($this->connectionTz);
 			} else {

src/Utils/DateTimeImmutable.php

@@ -19,6 +19,9 @@ public function setTimestamp($timestamp): self
 	{
 		$zone = $this->getTimezone();
 		$datetime = new static('@' . (string) $timestamp);
+		if ($zone === false) { // @phpstan-ignore-line
+			return $datetime;
+		}
 		return $datetime->setTimezone($zone);
 	}
 }