Fix parsing of export const

corpus/stmt/const.nu

@@ -47,3 +47,39 @@ const x = 42 | math sin
         (command
           (cmd_identifier)
           (val_string))))))
+
+=====
+const-004-exported
+=====
+
+export const x = 42
+
+----
+
+(nu_script
+  (stmt_const
+    (identifier)
+    (pipeline
+      (pipe_element
+        (val_number)))))
+
+=====
+const-005-exported-multiple
+=====
+
+export const GAMMA = 0.5772156649015329
+export const E = 2.718281828459045
+
+----
+
+(nu_script
+  (stmt_const
+    (identifier)
+    (pipeline
+      (pipe_element
+        (val_number))))
+  (stmt_const
+    (identifier)
+    (pipeline
+      (pipe_element
+        (val_number)))))

grammar.js

@@ -945,7 +945,7 @@ module.exports = grammar({
 /// To correctly parse these situations distinct rules for different types of
 /// statements are needed. These rules are differentiated by suffix, and only
 /// difference between them is terminator parameter used in pipeline rule that
-/// is terminating statements. This function automaticaly generates all rules
+/// is terminating statements. This function automatically generates all rules
 /// for a given terminator and names them with specified suffix.
 function block_body_rules(suffix, terminator) {
   function alias_for_suffix($, rule_name, suffix) {
@@ -995,7 +995,14 @@ function block_body_rules(suffix, terminator) {
       prec.right(1, seq(KEYWORD().mut, $["_assignment_pattern" + suffix])),
 
     ["stmt_const" + suffix]: ($) =>
-      prec.right(1, seq(KEYWORD().const, $["_assignment_pattern" + suffix])),
+      prec.right(
+        1,
+        seq(
+          optional(MODIFIER().visibility),
+          KEYWORD().const,
+          $["_assignment_pattern" + suffix],
+        ),
+      ),
 
     ["_assignment_pattern" + suffix]: ($) =>
       seq(

src/grammar.json

@@ -176,6 +176,18 @@
       "content": {
         "type": "SEQ",
         "members": [
+          {
+            "type": "CHOICE",
+            "members": [
+              {
+                "type": "STRING",
+                "value": "export"
+              },
+              {
+                "type": "BLANK"
+              }
+            ]
+          },
           {
             "type": "STRING",
             "value": "const"
@@ -444,6 +456,18 @@
       "content": {
         "type": "SEQ",
         "members": [
+          {
+            "type": "CHOICE",
+            "members": [
+              {
+                "type": "STRING",
+                "value": "export"
+              },
+              {
+                "type": "BLANK"
+              }
+            ]
+          },
           {
             "type": "STRING",
             "value": "const"