find another potential precedence issue with non null assertions, also added some more null aware syntax

grammar.js

@@ -157,7 +157,6 @@ module.exports = grammar({
         [$.assignable_expression],
         [$.assignable_selector_part, $.selector],
         [$.postfix_expression],
-        [$._top_level_definition, $._final_const_var_or_type],
         [$.assignable_expression, $._primary],
         [$._declared_identifier],
         [$.equality_expression],
@@ -174,6 +173,7 @@ module.exports = grammar({
         [$._postfix_expression, $.assignable_expression],
         [$._postfix_expression],
         [$._top_level_definition, $.lambda_expression],
+        [$._top_level_definition, $._final_const_var_or_type],
         [$._top_level_definition, $.const_object_expression, $._final_const_var_or_type],
         [$._final_const_var_or_type, $.const_object_expression],
         [$._final_const_var_or_type],
@@ -1843,12 +1843,13 @@ module.exports = grammar({
                 $.static_final_declaration_list
             ),
             seq(
-                $._final_builtin,
+                optional($._late_builtin), $._final_builtin,
                 optional($._type),
                 $.initialized_identifier_list
             ),
             seq(
                 optional($._static_or_covariant),
+                optional($._late_builtin),
                 choice(
                     $._type,
                     $.inferred_type
@@ -2173,6 +2174,7 @@ module.exports = grammar({
         _final_const_var_or_type: $ => choice(
             seq($._final_builtin, optional($._type)),
             seq($._const_builtin, optional($._type)),
+            seq($._late_builtin, optional($._final_builtin), optional($._type)),
             $.inferred_type,
             $._type
         ),
@@ -2195,7 +2197,9 @@ module.exports = grammar({
             choice(
                 seq(
                     $._type_name,
-                    optional($.type_arguments)
+                    optional($._nullable_type),
+                    optional($.type_arguments),
+                    optional($._nullable_type)
                 ),
                 $._function_builtin_identifier
             )
@@ -2758,6 +2762,10 @@ module.exports = grammar({
             DART_PREC.BUILTIN,
             'final',
         ),
+        _late_builtin: $ => prec(
+            DART_PREC.BUILTIN,
+            'late',
+        ),
         _external_builtin: $ => prec(
             DART_PREC.BUILTIN,
             'external',

src/grammar.json

@@ -6905,6 +6905,18 @@
         {
           "type": "SEQ",
           "members": [
+            {
+              "type": "CHOICE",
+              "members": [
+                {
+                  "type": "SYMBOL",
+                  "name": "_late_builtin"
+                },
+                {
+                  "type": "BLANK"
+                }
+              ]
+            },
             {
               "type": "SYMBOL",
               "name": "_final_builtin"
@@ -6942,6 +6954,18 @@
                 }
               ]
             },
+            {
+              "type": "CHOICE",
+              "members": [
+                {
+                  "type": "SYMBOL",
+                  "name": "_late_builtin"
+                },
+                {
+                  "type": "BLANK"
+                }
+              ]
+            },
             {
               "type": "CHOICE",
               "members": [
@@ -7933,6 +7957,39 @@
             }
           ]
         },
+        {
+          "type": "SEQ",
+          "members": [
+            {
+              "type": "SYMBOL",
+              "name": "_late_builtin"
+            },
+            {
+              "type": "CHOICE",
+              "members": [
+                {
+                  "type": "SYMBOL",
+                  "name": "_final_builtin"
+                },
+                {
+                  "type": "BLANK"
+                }
+              ]
+            },
+            {
+              "type": "CHOICE",
+              "members": [
+                {
+                  "type": "SYMBOL",
+                  "name": "_type"
+                },
+                {
+                  "type": "BLANK"
+                }
+              ]
+            }
+          ]
+        },
         {
           "type": "SYMBOL",
           "name": "inferred_type"
@@ -7995,6 +8052,18 @@
                 "type": "SYMBOL",
                 "name": "_type_name"
               },
+              {
+                "type": "CHOICE",
+                "members": [
+                  {
+                    "type": "SYMBOL",
+                    "name": "_nullable_type"
+                  },
+                  {
+                    "type": "BLANK"
+                  }
+                ]
+              },
               {
                 "type": "CHOICE",
                 "members": [
@@ -8006,6 +8075,18 @@
                     "type": "BLANK"
                   }
                 ]
+              },
+              {
+                "type": "CHOICE",
+                "members": [
+                  {
+                    "type": "SYMBOL",
+                    "name": "_nullable_type"
+                  },
+                  {
+                    "type": "BLANK"
+                  }
+                ]
               }
             ]
           },
@@ -9699,6 +9780,14 @@
         "value": "final"
       }
     },
+    "_late_builtin": {
+      "type": "PREC",
+      "value": 0,
+      "content": {
+        "type": "STRING",
+        "value": "late"
+      }
+    },
     "_external_builtin": {
       "type": "PREC",
       "value": 0,
@@ -9878,10 +9967,6 @@
     [
       "postfix_expression"
     ],
-    [
-      "_top_level_definition",
-      "_final_const_var_or_type"
-    ],
     [
       "assignable_expression",
       "_primary"
@@ -9939,6 +10024,10 @@
       "_top_level_definition",
       "lambda_expression"
     ],
+    [
+      "_top_level_definition",
+      "_final_const_var_or_type"
+    ],
     [
       "_top_level_definition",
       "const_object_expression",

src/node-types.json

@@ -10712,6 +10712,10 @@
     "type": "is",
     "named": false
   },
+  {
+    "type": "late",
+    "named": false
+  },
   {
     "type": "library",
     "named": false

test/corpus/expressions.txt

@@ -370,3 +370,14 @@ if (data['frame_count'] as int < 5) {
 }
 
 ---
+
+(program )
+
+
+==========================
+Simple non-null assertion
+==========================
+
+my!.size = 1;
+
+---