Fix the parsing error in MSSQL for multiple statements that include DECLARE statements (#1497)

src/parser/mod.rs

@@ -5321,9 +5321,22 @@ impl<'a> Parser<'a> {
     /// ```
     /// [MsSql]: https://learn.microsoft.com/en-us/sql/t-sql/language-elements/declare-local-variable-transact-sql?view=sql-server-ver16
     pub fn parse_mssql_declare(&mut self) -> Result<Statement, ParserError> {
-        let mut stmts = vec![];
+        let stmts = self.parse_comma_separated(Parser::parse_mssql_declare_stmt)?;
 
-        loop {
+        Ok(Statement::Declare { stmts })
+    }
+
+    /// Parse the body of a [MsSql] `DECLARE`statement.
+    ///
+    /// Syntax:
+    /// ```text
+    // {
+    //   { @local_variable [AS] data_type [ = value ] }
+    //   | { @cursor_variable_name CURSOR }
+    // } [ ,...n ]
+    /// ```
+    /// [MsSql]: https://learn.microsoft.com/en-us/sql/t-sql/language-elements/declare-local-variable-transact-sql?view=sql-server-ver16
+    pub fn parse_mssql_declare_stmt(&mut self) -> Result<Declare, ParserError> {
         let name = {
             let ident = self.parse_identifier(false)?;
             if !ident.value.starts_with('@') {
@@ -5352,7 +5365,7 @@ impl<'a> Parser<'a> {
 
         let assignment = self.parse_mssql_variable_declaration_expression()?;
 
-            stmts.push(Declare {
+        Ok(Declare {
             names: vec![name],
             data_type,
             assignment,
@@ -5362,14 +5375,7 @@ impl<'a> Parser<'a> {
             scroll: None,
             hold: None,
             for_query: None,
-            });
-
-            if self.next_token() != Token::Comma {
-                break;
-            }
-        }
-
-        Ok(Statement::Declare { stmts })
+        })
     }
 
     /// Parses the assigned expression in a variable declaration.

tests/sqlparser_mssql.rs

@@ -29,7 +29,7 @@ use sqlparser::ast::DeclareAssignment::MsSqlAssignment;
 use sqlparser::ast::Value::SingleQuotedString;
 use sqlparser::ast::*;
 use sqlparser::dialect::{GenericDialect, MsSqlDialect};
-use sqlparser::parser::{Parser, ParserError};
+use sqlparser::parser::ParserError;
 
 #[test]
 fn parse_mssql_identifiers() {
@@ -910,7 +910,7 @@ fn parse_substring_in_select() {
 #[test]
 fn parse_mssql_declare() {
     let sql = "DECLARE @foo CURSOR, @bar INT, @baz AS TEXT = 'foobar';";
-    let ast = Parser::parse_sql(&MsSqlDialect {}, sql).unwrap();
+    let ast = ms().parse_sql_statements(sql).unwrap();
 
     assert_eq!(
         vec![Statement::Declare {
@@ -963,6 +963,73 @@ fn parse_mssql_declare() {
         }],
         ast
     );
+
+    let sql = "DECLARE @bar INT;SET @bar = 2;SELECT @bar * 4";
+    let ast = ms().parse_sql_statements(sql).unwrap();
+    assert_eq!(
+        vec![
+            Statement::Declare {
+                stmts: vec![Declare {
+                    names: vec![Ident {
+                        value: "@bar".to_string(),
+                        quote_style: None
+                    }],
+                    data_type: Some(Int(None)),
+                    assignment: None,
+                    declare_type: None,
+                    binary: None,
+                    sensitive: None,
+                    scroll: None,
+                    hold: None,
+                    for_query: None
+                }]
+            },
+            Statement::SetVariable {
+                local: false,
+                hivevar: false,
+                variables: OneOrManyWithParens::One(ObjectName(vec![Ident::new("@bar")])),
+                value: vec![Expr::Value(Value::Number("2".parse().unwrap(), false))],
+            },
+            Statement::Query(Box::new(Query {
+                with: None,
+                limit: None,
+                limit_by: vec![],
+                offset: None,
+                fetch: None,
+                locks: vec![],
+                for_clause: None,
+                order_by: None,
+                settings: None,
+                format_clause: None,
+                body: Box::new(SetExpr::Select(Box::new(Select {
+                    distinct: None,
+                    top: None,
+                    top_before_distinct: false,
+                    projection: vec![SelectItem::UnnamedExpr(Expr::BinaryOp {
+                        left: Box::new(Expr::Identifier(Ident::new("@bar"))),
+                        op: BinaryOperator::Multiply,
+                        right: Box::new(Expr::Value(Value::Number("4".parse().unwrap(), false))),
+                    })],
+                    into: None,
+                    from: vec![],
+                    lateral_views: vec![],
+                    prewhere: None,
+                    selection: None,
+                    group_by: GroupByExpr::Expressions(vec![], vec![]),
+                    cluster_by: vec![],
+                    distribute_by: vec![],
+                    sort_by: vec![],
+                    having: None,
+                    named_window: vec![],
+                    window_before_qualify: false,
+                    qualify: None,
+                    value_table_mode: None,
+                    connect_by: None,
+                })))
+            }))
+        ],
+        ast
+    );
 }
 
 #[test]