WIP: Add '>|' redirection to grammar (#75)

* Add '>|' redirection to grammar

* add tests for >|

* generate grammar

corpus/commands.txt

@@ -100,6 +100,23 @@ cat a b > /dev/null
     (file_redirect (file_descriptor) (word))
     (command_name (word))))
 
+===============================
+File redirects (noclobber override)
+===============================
+
+whoami >| /dev/null
+cat a b >| /dev/null
+
+---
+
+(program
+  (redirected_statement
+    (command (command_name (word)))
+    (file_redirect (word)))
+  (redirected_statement
+    (command (command_name (word)) (word) (word))
+    (file_redirect (word))))
+
 ===============================
 Heredoc redirects
 ===============================

grammar.js

@@ -320,7 +320,7 @@ module.exports = grammar({
 
     file_redirect: $ => prec.left(seq(
       field('descriptor', optional($.file_descriptor)),
-      choice('<', '>', '>>', '&>', '&>>', '<&', '>&'),
+      choice('<', '>', '>>', '&>', '&>>', '<&', '>&', '>|'),
       field('destination', $._literal)
     )),
 

src/grammar.json

@@ -1371,6 +1371,10 @@
               {
                 "type": "STRING",
                 "value": ">&"
+              },
+              {
+                "type": "STRING",
+                "value": ">|"
               }
             ]
           },

src/node-types.json

@@ -1419,6 +1419,10 @@
     "type": ">>",
     "named": false
   },
+  {
+    "type": ">|",
+    "named": false
+  },
   {
     "type": "[",
     "named": false