MySQL dialect: Add support for hash comments (apache#1466)

Author: hansott

src/tokenizer.rs

@@ -43,7 +43,8 @@ use sqlparser_derive::{Visit, VisitMut};
 use crate::ast::DollarQuotedString;
 use crate::dialect::Dialect;
 use crate::dialect::{
-    BigQueryDialect, DuckDbDialect, GenericDialect, PostgreSqlDialect, SnowflakeDialect,
+    BigQueryDialect, DuckDbDialect, GenericDialect, MySqlDialect, PostgreSqlDialect,
+    SnowflakeDialect,
 };
 use crate::keywords::{Keyword, ALL_KEYWORDS, ALL_KEYWORDS_INDEX};
 
@@ -1140,7 +1141,7 @@ impl<'a> Tokenizer<'a> {
                 }
                 '{' => self.consume_and_return(chars, Token::LBrace),
                 '}' => self.consume_and_return(chars, Token::RBrace),
-                '#' if dialect_of!(self is SnowflakeDialect | BigQueryDialect) => {
+                '#' if dialect_of!(self is SnowflakeDialect | BigQueryDialect | MySqlDialect) => {
                     chars.next(); // consume the '#', starting a snowflake single-line comment
                     let comment = self.tokenize_single_line_comment(chars);
                     Ok(Some(Token::Whitespace(Whitespace::SingleLineComment {

tests/sqlparser_common.rs

@@ -9923,7 +9923,11 @@ fn test_release_savepoint() {
 #[test]
 fn test_comment_hash_syntax() {
     let dialects = TestedDialects {
-        dialects: vec![Box::new(BigQueryDialect {}), Box::new(SnowflakeDialect {})],
+        dialects: vec![
+            Box::new(BigQueryDialect {}),
+            Box::new(SnowflakeDialect {}),
+            Box::new(MySqlDialect {}),
+        ],
         options: None,
     };
     let sql = r#"