Ensure that for empty default date fields there is no default

Author: wojtekn

tests/WP_SQLite_Translator_Tests.php

@@ -293,7 +293,7 @@ public function testShowCreateTable1() {
 	public function testShowCreateTableWithEmptyDatetimeDefault() {
 		$this->assertQuery(
 			"CREATE TABLE _tmp_table (
-				ID BIGINT PRIMARY KEY AUTO_INCREMENT NOT NULL,
+				ID BIGINT PRIMARY KEY AUTO_INCREMENT,
 				timestamp1 datetime NOT NULL,
 				timestamp2 date NOT NULL,
 				timestamp3 time NOT NULL,
@@ -308,13 +308,14 @@ public function testShowCreateTableWithEmptyDatetimeDefault() {
 		$results = $this->engine->get_query_results();
 
 		$this->assertEquals(
-			"CREATE TABLE _tmp_table (
-	`ID` bigint PRIMARY KEY AUTO_INCREMENT NOT NULL,
+			"CREATE TABLE `_tmp_table` (
+	`ID` bigint AUTO_INCREMENT,
 	`timestamp1` datetime NOT NULL,
 	`timestamp2` date NOT NULL,
 	`timestamp3` time NOT NULL,
 	`timestamp4` timestamp NOT NULL,
-	`timestamp5` year NOT NULL
+	`timestamp5` year NOT NULL,
+	PRIMARY KEY (`ID`)
 );",
 			$results[0]->{'Create Table'}
 		);

wp-includes/sqlite/class-wp-sqlite-translator.php

@@ -3693,16 +3693,17 @@ protected function get_column_definitions( $table_name, $columns ) {
 		$auto_increment_column = $this->get_autoincrement_column( $table_name );
 		$column_definitions    = array();
 		foreach ( $columns as $column ) {
+			$mysql_type = $this->get_cached_mysql_data_type( $table_name, $column->name );
 			$is_auto_incr = $auto_increment_column && strtolower( $auto_increment_column ) === strtolower( $column->name );
 			$definition   = array();
 			$definition[] = '`' . $column->name . '`';
-			$definition[] = $this->get_cached_mysql_data_type( $table_name, $column->name ) ?? $column->name;
+			$definition[] = $mysql_type ?? $column->name;
 
 			if ( '1' === $column->notnull ) {
 				$definition[] = 'NOT NULL';
 			}
 
-			if ( null !== $column->dflt_value && '' !== $column->dflt_value && ! $is_auto_incr ) {
+			if ( $this->column_has_default( $column, $mysql_type ) && ! $is_auto_incr ) {
 				$definition[] = 'DEFAULT ' . $column->dflt_value;
 			}
 
@@ -3858,6 +3859,22 @@ function ( $row ) use ( $name_map ) {
 		);
 	}
 
+	/**
+	 * Checks if column should define the default.
+	 *
+	 * @param stdClass $column The table column
+	 * @param string $mysql_type The MySQL data type
+	 *
+	 * @return boolean If column should have a default definition.
+	 */
+	private function column_has_default( $column, $mysql_type )  {
+		if ( null !== $column->dflt_value && '' !== $column->dflt_value && ! in_array( strtolower( $mysql_type ), array( 'datetime', 'date', 'time', 'timestamp', 'year' ), true ) ) {
+			return true;
+		}
+
+		return false;
+	}
+
 	/**
 	 * Consumes data types from the query.
 	 *