Add async syntax

corpus/async.txt

@@ -0,0 +1,84 @@
+==================
+Simple Async Statements
+==================
+
+async (output 'Whaddup')
+
+---
+
+(root
+  (item
+    (statement
+      (async
+        (item
+          (statement
+            (expression
+              (function_call
+                (tool)
+                (expression
+                  (value
+                    (string)))))))))))
+
+==================
+Complex Run Statements
+==================
+
+async if 1 % 2 == 0 {
+  (output 'true')
+} else {
+  (output 'false')
+}
+
+async (output 'foobar')
+
+---
+
+(root
+  (item
+    (statement
+      (async
+        (item
+          (statement
+            (if_else
+              (if
+                (expression
+                  (logic
+                    (expression
+                      (math
+                        (expression
+                          (value
+                            (integer)))
+                        (math_operator)
+                        (expression
+                          (value
+                            (integer)))))
+                    (logic_operator)
+                    (expression
+                      (value
+                        (integer)))))
+                (statement
+                  (expression
+                    (function_call
+                      (tool)
+                      (expression
+                        (value
+                          (string)))))))
+              (else
+                (statement
+                  (expression
+                    (function_call
+                      (tool)
+                      (expression
+                        (value
+                          (string)))))))))))))
+  (item
+    (statement
+      (async
+        (item
+          (statement
+            (expression
+              (function_call
+                (tool)
+                (expression
+                  (value
+                    (string)))))))))))

grammar.js

@@ -16,6 +16,7 @@ module.exports = grammar({
       $.insert,
       $.select,
       $.while,
+      $.async,
     ),
   
     comment: $ => seq(/[#]+.*/),
@@ -234,5 +235,7 @@ module.exports = grammar({
         seq('where', $.logic)
       ),
     )),
+
+    async: $ => seq('async', $.item),
   }
 });

src/grammar.json

@@ -50,6 +50,10 @@
         {
           "type": "SYMBOL",
           "name": "while"
+        },
+        {
+          "type": "SYMBOL",
+          "name": "async"
         }
       ]
     },
@@ -942,6 +946,19 @@
           }
         ]
       }
+    },
+    "async": {
+      "type": "SEQ",
+      "members": [
+        {
+          "type": "STRING",
+          "value": "async"
+        },
+        {
+          "type": "SYMBOL",
+          "name": "item"
+        }
+      ]
     }
   },
   "extras": [

src/node-types.json

@@ -27,6 +27,21 @@
     "named": true,
     "fields": {}
   },
+  {
+    "type": "async",
+    "named": true,
+    "fields": {},
+    "children": {
+      "multiple": false,
+      "required": true,
+      "types": [
+        {
+          "type": "item",
+          "named": true
+        }
+      ]
+    }
+  },
   {
     "type": "boolean",
     "named": true,
@@ -352,6 +367,10 @@
           "type": "assignment",
           "named": true
         },
+        {
+          "type": "async",
+          "named": true
+        },
         {
           "type": "comment",
           "named": true
@@ -553,6 +572,10 @@
     "type": "assert_equal",
     "named": false
   },
+  {
+    "type": "async",
+    "named": false
+  },
   {
     "type": "bash",
     "named": false