fix: unary negation operator with operators: Mul, Div and Mod (#902)

Author: izveigor

src/parser.rs

@@ -799,7 +799,7 @@ impl<'a> Parser<'a> {
                 };
                 Ok(Expr::UnaryOp {
                     op,
-                    expr: Box::new(self.parse_subexpr(Self::PLUS_MINUS_PREC)?),
+                    expr: Box::new(self.parse_subexpr(Self::MUL_DIV_MOD_OP_PREC)?),
                 })
             }
             tok @ Token::DoubleExclamationMark
@@ -1964,6 +1964,7 @@ impl<'a> Parser<'a> {
     }
 
     // use https://www.postgresql.org/docs/7.0/operators.htm#AEN2026 as a reference
+    const MUL_DIV_MOD_OP_PREC: u8 = 40;
     const PLUS_MINUS_PREC: u8 = 30;
     const XOR_PREC: u8 = 24;
     const TIME_ZONE_PREC: u8 = 20;
@@ -1974,8 +1975,6 @@ impl<'a> Parser<'a> {
     const AND_PREC: u8 = 10;
     const OR_PREC: u8 = 5;
 
-    const DIV_OP_PREC: u8 = 40;
-
     /// Get the precedence of the next token
     pub fn get_next_precedence(&self) -> Result<u8, ParserError> {
         // allow the dialect to override precedence logic
@@ -2025,7 +2024,7 @@ impl<'a> Parser<'a> {
             Token::Word(w) if w.keyword == Keyword::ILIKE => Ok(Self::LIKE_PREC),
             Token::Word(w) if w.keyword == Keyword::SIMILAR => Ok(Self::LIKE_PREC),
             Token::Word(w) if w.keyword == Keyword::OPERATOR => Ok(Self::BETWEEN_PREC),
-            Token::Word(w) if w.keyword == Keyword::DIV => Ok(Self::DIV_OP_PREC),
+            Token::Word(w) if w.keyword == Keyword::DIV => Ok(Self::MUL_DIV_MOD_OP_PREC),
             Token::Eq
             | Token::Lt
             | Token::LtEq
@@ -2043,7 +2042,7 @@ impl<'a> Parser<'a> {
             Token::Ampersand => Ok(23),
             Token::Plus | Token::Minus => Ok(Self::PLUS_MINUS_PREC),
             Token::Mul | Token::Div | Token::DuckIntDiv | Token::Mod | Token::StringConcat => {
-                Ok(40)
+                Ok(Self::MUL_DIV_MOD_OP_PREC)
             }
             Token::DoubleColon => Ok(50),
             Token::Colon => Ok(50),

tests/sqlparser_common.rs

@@ -1074,7 +1074,7 @@ fn parse_compound_expr_2() {
 }
 
 #[test]
-fn parse_unary_math() {
+fn parse_unary_math_with_plus() {
     use self::Expr::*;
     let sql = "-a + -b";
     assert_eq!(
@@ -1093,6 +1093,26 @@ fn parse_unary_math() {
     );
 }
 
+#[test]
+fn parse_unary_math_with_multiply() {
+    use self::Expr::*;
+    let sql = "-a * -b";
+    assert_eq!(
+        BinaryOp {
+            left: Box::new(UnaryOp {
+                op: UnaryOperator::Minus,
+                expr: Box::new(Identifier(Ident::new("a"))),
+            }),
+            op: BinaryOperator::Multiply,
+            right: Box::new(UnaryOp {
+                op: UnaryOperator::Minus,
+                expr: Box::new(Identifier(Ident::new("b"))),
+            }),
+        },
+        verified_expr(sql)
+    );
+}
+
 #[test]
 fn parse_is_null() {
     use self::Expr::*;