Validate AliasMethodNode

Author: thomasmarshall

config.yml

@@ -852,8 +852,7 @@ nodes:
         kind:
           - SymbolNode
           - InterpolatedSymbolNode
-          - on error: GlobalVariableReadNode # alias a $b
-          - on error: ErrorRecoveryNode # alias a 42
+          - on error: ErrorRecoveryNode
         comment: |
           Represents the old name of the method that will be aliased.
 

src/prism.c

@@ -18218,9 +18218,12 @@ parse_expression_prefix(pm_parser_t *parser, pm_binding_power_t binding_power, b
                     if (!PM_NODE_TYPE_P(old_name, PM_SYMBOL_NODE) && !PM_NODE_TYPE_P(old_name, PM_INTERPOLATED_SYMBOL_NODE)) {
                         pm_parser_err_node(parser, old_name, PM_ERR_ALIAS_ARGUMENT);
                     }
+
+                    PM_VALIDATE_NODE_TYPE(parser, old_name, PM_SYMBOL_NODE, PM_INTERPOLATED_SYMBOL_NODE);
                 }
                 PRISM_FALLTHROUGH
                 default:
+                    PM_VALIDATE_NODE_TYPE(parser, old_name, PM_SYMBOL_NODE, PM_INTERPOLATED_SYMBOL_NODE);
                     return UP(pm_alias_method_node_create(parser, &keyword, new_name, old_name));
             }
         }

test/prism/result/error_recovery_test.rb

@@ -27,7 +27,8 @@ def test_alias_method_node_old_name_global_variable
       refute result.success?
 
       node = result.value.statements.body.first
-      assert_kind_of GlobalVariableReadNode, node.old_name
+      assert_kind_of ErrorRecoveryNode, node.old_name
+      assert_kind_of GlobalVariableReadNode, node.old_name.child
     end
 
     def test_alias_method_node_old_name_missing
@@ -36,6 +37,7 @@ def test_alias_method_node_old_name_missing
 
       node = result.value.statements.body.first
       assert_kind_of ErrorRecoveryNode, node.old_name
+      assert_nil node.old_name.child
     end
 
     def test_class_node_constant_path_call