support multiple order directions

Author: andykent

lib/grammar.coffee

@@ -44,12 +44,21 @@ grammar =
   ]
 
   LimitClause: [
-    o 'LIMIT Number',                                 -> new Limit($2)
+    o 'LIMIT Number',                                     -> new Limit($2)
   ]
 
-  # TODO: order by can take mulitple sorts and also the direction is optional
   OrderClause: [
-    o 'ORDER BY Value DIRECTION',                         -> new Order($3, $4)
+    o 'ORDER BY OrderArgs',                               -> new Order($3)
+  ]
+  
+  OrderArgs: [
+    o 'OrderArg',                                         -> [$1]
+    o 'OrderArgs SEPARATOR OrderArg',                     -> $1.concat($3)
+  ]
+  
+  OrderArg: [
+    o 'Value',                                            -> new OrderArgument($1, 'ASC')
+    o 'Value DIRECTION',                                  -> new OrderArgument($1, $2)    
   ]
 
   GroupClause: [

lib/lexer.coffee

@@ -65,7 +65,6 @@ class Lexer
 
   starToken:        -> @tokenizeFromRegex('STAR', STAR)
   seperatorToken:   -> @tokenizeFromRegex('SEPARATOR', SEPARATOR)
-  # whitespaceToken:  -> @tokenizeFromRegex('WHITESPACE', WHITESPACE, 0, 0, @preserveWhitespace)
   literalToken:     -> @tokenizeFromRegex('LITERAL', LITERAL, 1, 0)
   numberToken:      -> @tokenizeFromRegex('NUMBER', NUMBER)
   stringToken:      -> @tokenizeFromRegex('STRING', STRING, 1, 0)

lib/nodes.coffee

@@ -26,8 +26,12 @@ exports.NumberValue = class LiteralValue
   toString: -> @value.toString()
 
 exports.Order = class Order
+  constructor: (@orderings) ->
+  toString: -> "ORDER BY #{@orderings.join(', ')}"
+
+exports.OrderArgument = class OrderArgument
   constructor: (@value, @direction='ASC') -> null
-  toString: -> "ORDER BY #{@value} #{@direction}"
+  toString: -> "#{@value} #{@direction}"
 
 exports.Limit = class Limit
   constructor: (@value) -> null

spec/grammar.spec.coffee

@@ -35,6 +35,22 @@ describe "SQL Grammer", ->
       """
 
     it "parses WHERE with ORDER BY clauses", ->
+      expect(parse("SELECT * FROM my_table WHERE x > 1 ORDER BY y").toString()).toEqual """
+      SELECT *
+        FROM `my_table`
+        WHERE `x` > 1
+        ORDER BY `y` ASC
+      """
+
+    it "parses WHERE with multiple ORDER BY clauses", ->
+      expect(parse("SELECT * FROM my_table WHERE x > 1 ORDER BY x, y DESC").toString()).toEqual """
+      SELECT *
+        FROM `my_table`
+        WHERE `x` > 1
+        ORDER BY `x` ASC, `y` DESC
+      """
+
+    it "parses WHERE with ORDER BY clauses with direction", ->
       expect(parse("SELECT * FROM my_table WHERE x > 1 ORDER BY y ASC").toString()).toEqual """
       SELECT *
         FROM `my_table`