Add function statement

Author: Azganoth

corpus/functions.txt

@@ -31,3 +31,35 @@ a.b.f = function(self, test, ...) return 10 end
   (variable_declaration (variable_declarator (identifier) (property_identifier) (property_identifier))
     (function_definition (parameters (self) (identifier) (spread))
       (return_statement (number)))))
+
+============================================
+Function statements
+============================================
+
+function f()
+  return false
+end
+
+f = function() return false end
+
+function t.a.b.c.f()
+  return true
+end
+
+t.a.b.c.f = function() return true end
+
+---
+
+(lua
+  (function (function_name (identifier)) (parameters)
+    (return_statement (false)))
+
+  (variable_declaration (variable_declarator (identifier))
+    (function_definition (parameters)
+      (return_statement (false))))
+
+  (function (function_name (identifier) (property_identifier) (property_identifier) (property_identifier) (property_identifier)) (parameters)
+    (return_statement (true)))
+
+  (variable_declaration (variable_declarator (identifier) (property_identifier) (property_identifier) (property_identifier) (property_identifier)) (function_definition (parameters)
+    (return_statement (true)))))

grammar.js

@@ -65,7 +65,9 @@ module.exports = grammar({
       $.break_statement,
 
       $.label_statement,
-      $._empty_statement
+      $._empty_statement,
+
+      alias($.function_statement, $.function)
     ),
 
     // Declarations
@@ -191,6 +193,18 @@ module.exports = grammar({
     _empty_statement: $ => ';',
 
     // Functions
+    function_statement: $ => seq(
+      'function',
+      $.function_name,
+      $._function_body
+    ),
+
+    function_name: $ => seq(
+      $.identifier,
+      repeat(seq('.', alias($.identifier, $.property_identifier))),
+      optional(seq(':', alias($.identifier, $.method)))
+    ),
+
     parameters: $ => seq(
       '(',
       optional(choice(

src/grammar.json

@@ -121,6 +121,15 @@
         {
           "type": "SYMBOL",
           "name": "_empty_statement"
+        },
+        {
+          "type": "ALIAS",
+          "content": {
+            "type": "SYMBOL",
+            "name": "function_statement"
+          },
+          "named": true,
+          "value": "function"
         }
       ]
     },
@@ -814,6 +823,79 @@
       "type": "STRING",
       "value": ";"
     },
+    "function_statement": {
+      "type": "SEQ",
+      "members": [
+        {
+          "type": "STRING",
+          "value": "function"
+        },
+        {
+          "type": "SYMBOL",
+          "name": "function_name"
+        },
+        {
+          "type": "SYMBOL",
+          "name": "_function_body"
+        }
+      ]
+    },
+    "function_name": {
+      "type": "SEQ",
+      "members": [
+        {
+          "type": "SYMBOL",
+          "name": "identifier"
+        },
+        {
+          "type": "REPEAT",
+          "content": {
+            "type": "SEQ",
+            "members": [
+              {
+                "type": "STRING",
+                "value": "."
+              },
+              {
+                "type": "ALIAS",
+                "content": {
+                  "type": "SYMBOL",
+                  "name": "identifier"
+                },
+                "named": true,
+                "value": "property_identifier"
+              }
+            ]
+          }
+        },
+        {
+          "type": "CHOICE",
+          "members": [
+            {
+              "type": "SEQ",
+              "members": [
+                {
+                  "type": "STRING",
+                  "value": ":"
+                },
+                {
+                  "type": "ALIAS",
+                  "content": {
+                    "type": "SYMBOL",
+                    "name": "identifier"
+                  },
+                  "named": true,
+                  "value": "method"
+                }
+              ]
+            },
+            {
+              "type": "BLANK"
+            }
+          ]
+        }
+      ]
+    },
     "parameters": {
       "type": "SEQ",
       "members": [