export keyword works before class declaration, fixed export test

Author: leafo

docs/reference.md

@@ -586,6 +586,9 @@ variables directly:
 
     export some_number, message_str = 100, "hello world"
 
+Additionally, a class declaration can be prefixed with the export keyword in
+order to export it.
+
 ### Export All & Export Proper
 
 The `export` statement can also take special symbols `*` and `^`.

moonscript/parse.lua

@@ -410,7 +410,10 @@ local build_grammar = wrap(function()
 		TableBlock = SpaceBreak^1 * Advance * TableBlockInner * PopIndent / mark"table",
 
 		ClassDecl = key"class" * Name * (key"extends" * Exp + C"")^-1 * TableBlock / mark"class",
-		Export = key"export" * (Ct(NameList) * (sym"=" * Ct(ExpListLow))^-1  + op"*" + op"^") / mark"export",
+		Export = key"export" * (
+			Cc"class" * ClassDecl +
+			op"*" + op"^" +
+			Ct(NameList) * (sym"=" * Ct(ExpListLow))^-1) / mark"export",
 
 		KeyValue = (sym":" * Name) / self_assign + Ct((SimpleName + sym"[" * Exp * sym"]") * symx":" * (Exp + TableBlock)),
 		KeyValueList = KeyValue * (sym"," * KeyValue)^0,

moonscript/transform.lua

@@ -217,13 +217,26 @@ Statement = Transformer({
   end,
   export = function(node)
     if #node > 2 then
-      return build.group({
-        node,
-        build.assign({
-          names = node[2],
-          values = node[3]
+      if node[2] == "class" then
+        local cls = smart_node(node[3])
+        return build.group({
+          {
+            "export",
+            {
+              cls.name
+            }
+          },
+          cls
         })
-      })
+      else
+        return build.group({
+          node,
+          build.assign({
+            names = node[2],
+            values = node[3]
+          })
+        })
+      end
     else
       return nil
     end

moonscript/transform.moon

@@ -127,13 +127,20 @@ Statement = Transformer {
   export: (node) ->
     -- assign values if they are included
     if #node > 2
-      build.group {
-        node
-        build.assign {
-          names: node[2]
-          values: node[3]
+      if node[2] == "class"
+        cls = smart_node node[3]
+        build.group {
+          {"export", {cls.name}}
+          cls
+        }
+      else
+        build.group {
+          node
+          build.assign {
+            names: node[2]
+            values: node[3]
+          }
         }
-      }
     else
       nil
 

moonscript/types.lua

@@ -24,6 +24,16 @@ is_slice = function(node)
 end
 local t = { }
 local node_types = {
+  class = {
+    {
+      "name",
+      "Tmp"
+    },
+    {
+      "body",
+      t
+    }
+  },
   fndef = {
     {
       "args",

moonscript/types.moon

@@ -25,6 +25,10 @@ is_slice = (node) ->
 
 t = {}
 node_types = {
+  class: {
+    {"name", "Tmp"}
+    {"body", t}
+  }
   fndef: {
     {"args", t}
     {"whitelist", t}

tests/inputs/export.moon

@@ -1,4 +1,10 @@
 
+export a,b,c = 223, 343
+export cool = "dad"
+
+export class Something
+  umm: "cool"
+
 What = if this
   232
 else
@@ -36,5 +42,3 @@ with tmp
   j = 2000
 
 
-export a,b,c = 223, 343
-export cool = "dad"

tests/outputs/export.lua

@@ -1,3 +1,31 @@
+a, b, c = 223, 343
+cool = "dad"
+Something = (function()
+  local _parent_0 = nil
+  local _base_0 = {
+    umm = "cool"
+  }
+  _base_0.__index = _base_0
+  if _parent_0 then
+    setmetatable(_base_0, getmetatable(_parent_0).__index)
+  end
+  local _class_0 = setmetatable({
+    __init = function(self, ...)
+      if _parent_0 then
+        return _parent_0.__init(self, ...)
+      end
+    end
+  }, {
+    __index = _base_0,
+    __call = function(cls, ...)
+      local _self_0 = setmetatable({}, _base_0)
+      cls.__init(_self_0, ...)
+      return _self_0
+    end
+  })
+  _base_0.__class = _class_0
+  return _class_0
+end)()
 local What
 if this then
   What = 232
@@ -28,6 +56,4 @@ end
 do
   local _with_0 = tmp
   local j = 2000
-end
-a, b, c = 223, 343
-cool = "dad"
+end