trailing comma for tuple implemented

Jaseci-Labs · Sep 20, 2024 · a19e00b · a19e00b
1 parent 2896e1f
commit a19e00b
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Showing 2 changed files with 26 additions and 14 deletions.
diff --git a/jac/jaclang/compiler/jac.lark b/jac/jaclang/compiler/jac.lark
@@ -421,11 +421,11 @@ kv_pair: expression COLON expression | STAR_POW expression
 expr_list: (expr_list COMMA)? expression
 
 // Tuples and Jac Tuples
-tuple_list: expression COMMA expr_list COMMA kw_expr_list
-          | expression COMMA kw_expr_list
-          | expression COMMA expr_list
+tuple_list: expression COMMA expr_list COMMA kw_expr_list COMMA?
+          | expression COMMA kw_expr_list COMMA?
+          | expression COMMA expr_list COMMA?
           | expression COMMA
-          | kw_expr_list
+          | kw_expr_list COMMA?
 
 kw_expr_list: (kw_expr_list COMMA)? kw_expr
 kw_expr: named_ref EQ expression | STAR_POW expression

diff --git a/jac/jaclang/compiler/parser.py b/jac/jaclang/compiler/parser.py
@@ -2813,25 +2813,37 @@ def tuple_list(
         ) -> ast.SubNodeList[ast.Expr | ast.KWPair]:
             """Grammar rule.
 
-            tuple_list: expression COMMA expr_list COMMA kw_expr_list
-                    | expression COMMA kw_expr_list
-                    | expression COMMA expr_list
-                    | expression COMMA
-                    | kw_expr_list
+            tuple_list: expression COMMA expr_list    COMMA kw_expr_list COMMA?
+                      | expression COMMA kw_expr_list COMMA?
+                      | expression COMMA expr_list    COMMA?
+                      | expression COMMA
+                      | kw_expr_list COMMA?
             """
             chomp = [*kid]
             first_expr = None
             if isinstance(chomp[0], ast.SubNodeList):
+                # The chomp will be like this:
+                #     kw_expr_list, [COMMA]
+                if len(chomp) > 1:
+                    # Add the comma to the subnode list if it exists, otherwise the last comma will not be a part of
+                    # the ast, we need it for formatting.
+                    chomp[0].kid.append(chomp[1])
                 return self.nu(chomp[0])
             else:
-                first_expr = chomp[0]
-                chomp = chomp[2:]
+                # The chomp will be like this:
+                #     expression, COMMA, [subnode_list, [COMMA, [kw_expr_list, [COMMA]]]]
+                # Pop the first expression from chomp.
+                first_expr = chomp[0]   # Get the first expression.
+                chomp = chomp[2:]       # Get rid of expr and comma.
+
+            # The chomp will be like this:
+            #     [subnode_list, [COMMA, [kw_expr_list, [COMMA]]]]
             expr_list = []
             if len(chomp):
-                expr_list = chomp[0].kid
-                chomp = chomp[1:]
+                expr_list = chomp[0].kid  # Get the kids subnode list.
+                chomp = chomp[2:]         # Get rid of the subnode list and a comma if exists.
                 if len(chomp):
-                    chomp = chomp[1:]
+                    # The chomp will be like this: [kw_expr_list, [COMMA]]
                     expr_list = [*expr_list, *chomp[0].kid]
             expr_list = [first_expr, *expr_list]
             valid_kid = [i for i in expr_list if isinstance(i, (ast.Expr, ast.KWPair))]