set: allow negative ident values (#495)

Signed-off-by: Maciej Obuchowski <obuchowski.maciej@gmail.com>

src/parser.rs

@@ -3287,6 +3287,16 @@ impl<'a> Parser<'a> {
                 let value = match (self.parse_value(), token) {
                     (Ok(value), _) => SetVariableValue::Literal(value),
                     (Err(_), Token::Word(ident)) => SetVariableValue::Ident(ident.to_ident()),
+                    (Err(_), Token::Minus) => {
+                        let next_token = self.next_token();
+                        match next_token {
+                            Token::Word(ident) => SetVariableValue::Ident(Ident {
+                                quote_style: ident.quote_style,
+                                value: format!("-{}", ident.value),
+                            }),
+                            _ => self.expected("word", next_token)?,
+                        }
+                    }
                     (Err(_), unexpected) => self.expected("variable value", unexpected)?,
                 };
                 values.push(value);

tests/sqlparser_hive.rs

@@ -15,7 +15,9 @@
 //! Test SQL syntax specific to Hive. The parser based on the generic dialect
 //! is also tested (on the inputs it can handle).
 
+use sqlparser::ast::{Ident, ObjectName, SetVariableValue, Statement};
 use sqlparser::dialect::HiveDialect;
+use sqlparser::parser::ParserError;
 use sqlparser::test_utils::*;
 
 #[test]
@@ -205,6 +207,31 @@ fn from_cte() {
     println!("{}", hive().verified_stmt(rename));
 }
 
+#[test]
+fn set_statement_with_minus() {
+    assert_eq!(
+        hive().verified_stmt("SET hive.tez.java.opts = -Xmx4g"),
+        Statement::SetVariable {
+            local: false,
+            hivevar: false,
+            variable: ObjectName(vec![
+                Ident::new("hive"),
+                Ident::new("tez"),
+                Ident::new("java"),
+                Ident::new("opts")
+            ]),
+            value: vec![SetVariableValue::Ident("-Xmx4g".into())],
+        }
+    );
+
+    assert_eq!(
+        hive().parse_sql_statements("SET hive.tez.java.opts = -"),
+        Err(ParserError::ParserError(
+            "Expected word, found: EOF".to_string()
+        ))
+    )
+}
+
 fn hive() -> TestedDialects {
     TestedDialects {
         dialects: vec![Box::new(HiveDialect {})],