fixup: add precedence tests as well

Author: ryanschneider

tests/sqlparser_common.rs

@@ -15992,6 +15992,27 @@ fn parse_not_null_supported() {
     let _ = dialects.expr_parses_to("x NOT NULL", "x IS NOT NULL");
 }
 
+#[test]
+fn test_not_null_precedence() {
+    // For dialects which support it, `NOT NULL NOT NULL` should
+    // parse as `(NOT (NULL IS NOT NULL))`
+    let supported_dialects =
+        all_dialects_where(|d| d.supports_is_not_null_alias(IsNotNullAlias::NotSpaceNull));
+    let unsuported_dialects =
+        all_dialects_except(|d| d.supports_is_not_null_alias(IsNotNullAlias::NotSpaceNull));
+
+    assert_matches!(
+        supported_dialects.expr_parses_to("NOT NULL NOT NULL", "NOT NULL IS NOT NULL"),
+        Expr::UnaryOp {
+            op: UnaryOperator::Not,
+            ..
+        }
+    );
+
+    // for unsupported dialects, parsing should stop at `NOT NULL`
+    unsuported_dialects.expr_parses_to("NOT NULL NOT NULL", "NOT NULL");
+}
+
 #[test]
 fn parse_notnull_unsupported() {
     // Only Postgres, DuckDB, and SQLite support `x NOTNULL` as an expression
@@ -16008,3 +16029,24 @@ fn parse_notnull_supported() {
     let dialects = all_dialects_where(|d| d.supports_is_not_null_alias(IsNotNullAlias::NotNull));
     let _ = dialects.expr_parses_to("x NOTNULL", "x IS NOT NULL");
 }
+
+#[test]
+fn test_notnull_precedence() {
+    // For dialects which support it, `NOT NULL NOTNULL` should
+    // parse as `(NOT (NULL IS NOT NULL))`
+    let supported_dialects =
+        all_dialects_where(|d| d.supports_is_not_null_alias(IsNotNullAlias::NotNull));
+    let unsuported_dialects =
+        all_dialects_except(|d| d.supports_is_not_null_alias(IsNotNullAlias::NotNull));
+
+    assert_matches!(
+        supported_dialects.expr_parses_to("NOT NULL NOTNULL", "NOT NULL IS NOT NULL"),
+        Expr::UnaryOp {
+            op: UnaryOperator::Not,
+            ..
+        }
+    );
+
+    // for unsupported dialects, parsing should stop at `NOT NULL`
+    unsuported_dialects.expr_parses_to("NOT NULL NOTNULL", "NOT NULL");
+}