Fix quoted identifier regression edge-case with "from" in SELECT (#1346)

Author: alexander-beedie

src/parser/mod.rs

@@ -10331,7 +10331,7 @@ impl<'a> Parser<'a> {
             Expr::Wildcard => Ok(SelectItem::Wildcard(
                 self.parse_wildcard_additional_options()?,
             )),
-            Expr::Identifier(v) if v.value.to_lowercase() == "from" => {
+            Expr::Identifier(v) if v.value.to_lowercase() == "from" && v.quote_style.is_none() => {
                 parser_err!(
                     format!("Expected an expression, found: {}", v),
                     self.peek_token().location

tests/sqlparser_common.rs

@@ -9005,7 +9005,7 @@ fn parse_non_latin_identifiers() {
 
 #[test]
 fn parse_trailing_comma() {
-    // At the moment, Duck DB is the only dialect that allows
+    // At the moment, DuckDB is the only dialect that allows
     // trailing commas anywhere in the query
     let trailing_commas = TestedDialects {
         dialects: vec![Box::new(DuckDbDialect {})],
@@ -9038,11 +9038,16 @@ fn parse_trailing_comma() {
     );
 
     trailing_commas.verified_stmt("SELECT album_id, name FROM track");
-
     trailing_commas.verified_stmt("SELECT * FROM track ORDER BY milliseconds");
-
     trailing_commas.verified_stmt("SELECT DISTINCT ON (album_id) name FROM track");
 
+    // check quoted "from" identifier edge-case
+    trailing_commas.one_statement_parses_to(
+        r#"SELECT "from", FROM "from""#,
+        r#"SELECT "from" FROM "from""#,
+    );
+    trailing_commas.verified_stmt(r#"SELECT "from" FROM "from""#);
+
     // doesn't allow any trailing commas
     let trailing_commas = TestedDialects {
         dialects: vec![Box::new(GenericDialect {})],