Allow create table constraints to use data types as symbols

tests/WP_SQLite_Translator_Tests.php

@@ -1252,6 +1252,74 @@ public function testColumnWithOnUpdate() {
 		$this->assertNull( $result[0]->updated_at );
 	}
 
+	public function testDataTypeKeywordsAsKeyNames() {
+		// CREATE TABLE with a data type as a key name
+		$this->assertQuery(
+			'CREATE TABLE `_tmp_table` (
+				`id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
+				`timestamp` datetime NOT NULL,
+				PRIMARY KEY (`id`),
+				KEY `timestamp` (`timestamp`),
+			);'
+		);
+		$results = $this->assertQuery( 'DESCRIBE _tmp_table;' );
+		$this->assertEquals(
+			array(
+				(object) array(
+					'Field'   => 'id',
+					'Type'    => 'bigint(20) unsigned',
+					'Null'    => 'NO',
+					'Key'     => 'PRI',
+					'Default' => '0',
+					'Extra'   => '',
+				),
+				(object) array(
+					'Field'   => 'timestamp',
+					'Type'    => 'datetime',
+					'Null'    => 'NO',
+					'Key'     => '',
+					'Default' => null,
+					'Extra'   => '',
+				),
+			),
+			$results
+		);
+	}
+
+
+	public function testReservedKeywordsAsFieldNames() {
+		// CREATE TABLE with a reserved keyword as a field name
+		$this->assertQuery(
+			'CREATE TABLE `_tmp_table` (
+				`id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
+				`INDEX` timestamp,
+				PRIMARY KEY (`id`)
+			);'
+		);
+		$results = $this->assertQuery( 'DESCRIBE _tmp_table;' );
+		$this->assertEquals(
+			array(
+				(object) array(
+					'Field'   => 'id',
+					'Type'    => 'bigint(20) unsigned',
+					'Null'    => 'NO',
+					'Key'     => 'PRI',
+					'Default' => '0',
+					'Extra'   => '',
+				),
+				(object) array(
+					'Field'   => 'INDEX',
+					'Type'    => 'timestamp',
+					'Null'    => 'YES',
+					'Key'     => '',
+					'Default' => null,
+					'Extra'   => '',
+				),
+			),
+			$results
+		);
+	}
+
 	public function testColumnWithOnUpdateAndNoIdField() {
 		// CREATE TABLE with ON UPDATE
 		$this->assertQuery(

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

@@ -1013,15 +1013,25 @@ private function parse_create_table() {
 			 *
 			 * Lexer does not seem to reliably understand whether the
 			 * first token is a field name or a reserved keyword, so
-			 * instead we'll check whether the second non-whitespace
-			 * token is a data type.
+			 * alongside checking for the reserved keyword, we'll also
+			 * check whether the second non-whitespace token is a data type.
+			 *
+			 * By checking for the reserved keyword, we can be sure that
+			 * we're not parsing a constraint as a field when the
+			 * constraint symbol matches a data type.
 			 */
-			$second_token = $this->rewriter->peek_nth( 2 );
+			$current_token = $this->rewriter->peek();
+			$second_token  = $this->rewriter->peek_nth( 2 );
 
-			if ( $second_token->matches(
-				WP_SQLite_Token::TYPE_KEYWORD,
-				WP_SQLite_Token::FLAG_KEYWORD_DATA_TYPE
-			) ) {
+			if (
+				$second_token->matches(
+					WP_SQLite_Token::TYPE_KEYWORD,
+					WP_SQLite_Token::FLAG_KEYWORD_DATA_TYPE
+				) && ! $current_token->matches(
+					WP_SQLite_Token::TYPE_KEYWORD,
+					WP_SQLite_Token::FLAG_KEYWORD_RESERVED
+				)
+			) {
 				$result->fields[] = $this->parse_mysql_create_table_field();
 			} else {
 				$result->constraints[] = $this->parse_mysql_create_table_constraint();