fix: make order by ordering keyword optional (#17)

Author: YoEight

src/parser.rs

@@ -144,19 +144,17 @@ impl<'a> Parser<'a> {
         expect_keyword(self.shift(), "by")?;
 
         let expr = self.parse_expr()?;
-        let token = self.shift();
+        let token = self.peek();
 
         if let Sym::Id(name) = token.sym {
             let order = if name.eq_ignore_ascii_case("asc") {
+                self.shift();
                 Order::Asc
             } else if name.eq_ignore_ascii_case("desc") {
+                self.shift();
                 Order::Desc
             } else {
-                return Err(ParserError::UnexpectedToken(
-                    token.line,
-                    token.col,
-                    name.to_owned(),
-                ));
+                Order::Asc
             };
 
             return Ok(OrderBy { expr, order });

src/tests/parser.rs

@@ -90,3 +90,9 @@ fn test_parser_with_comment() {
     let tokens = tokenize(include_str!("./resources/with_comment.eql")).unwrap();
     insta::assert_yaml_snapshot!(parse(tokens.as_slice()));
 }
+
+#[test]
+fn test_parser_order_by_no_ordering() {
+    let tokens = tokenize(include_str!("./resources/query_order_by_no_ordering.eql")).unwrap();
+    insta::assert_yaml_snapshot!(parse(tokens.as_slice()));
+}

src/tests/resources/query_order_by_no_ordering.eql

@@ -0,0 +1,3 @@
+FROM e IN events
+ORDER BY e.data.price
+PROJECT INTO e

src/tests/snapshots/eventql_parser__tests__parser__parser_order_by_no_ordering.snap

@@ -0,0 +1,54 @@
+---
+source: src/tests/parser.rs
+expression: parse(tokens.as_slice())
+---
+Ok:
+  attrs:
+    pos:
+      line: 1
+      col: 1
+  sources:
+    - binding:
+        name: e
+        pos:
+          line: 1
+          col: 6
+      kind:
+        Name: events
+  predicate: ~
+  group_by: ~
+  order_by:
+    expr:
+      attrs:
+        pos:
+          line: 2
+          col: 10
+      value:
+        Access:
+          target:
+            attrs:
+              pos:
+                line: 2
+                col: 10
+            value:
+              Access:
+                target:
+                  attrs:
+                    pos:
+                      line: 2
+                      col: 10
+                  value:
+                    Id: e
+                field: data
+          field: price
+    order: Asc
+  limit: ~
+  projection:
+    attrs:
+      pos:
+        line: 3
+        col: 14
+    value:
+      Id: e
+  distinct: false
+  meta: ~