Adding '-' in front of a RegexAddress causes it to search in reverse

spec/extensions/command-interpreter-spec.coffee

@@ -105,6 +105,11 @@ describe "CommandInterpreter", ->
         interpreter.eval(editor, '/mike tyson')
         expect(editor.getSelection().getBufferRange()).toEqual [[3,8], [3,13]]
 
+      it "searches in reverse when prefixed with a -", ->
+        editor.setSelectedBufferRange([[5, 0], [5,1]])
+        interpreter.eval(editor, '-/pivot')
+        expect(editor.getSelection().getBufferRange()).toEqual [[3,8], [3,13]]
+
     describe "address range", ->
       describe "when two addresses are specified", ->
         it "selects from the begining of the left address to the end of the right address", ->

src/extensions/command-interpreter/commands.pegjs

@@ -28,7 +28,10 @@ primitiveAddress
   = lineNumber:integer { return new LineAddress(lineNumber) }
   / '$' { return new EofAddress() }
   / '.' { return new CurrentSelectionAddress() }
-  / '/' pattern:pattern '/'? { return new RegexAddress(pattern)}
+  / regexAddress
+
+regexAddress
+  = reverse:'-'? '/' pattern:pattern '/'? { return new RegexAddress(pattern, reverse.length > 0)}
 
 command = substitution / selectAllMatches
 

src/extensions/command-interpreter/regex-address.coffee

@@ -4,22 +4,28 @@ Range = require 'range'
 module.exports =
 class RegexAddress extends Address
   regex: null
+  reverse: null
 
-  constructor: (pattern) ->
+  constructor: (pattern, reverse) ->
+    @reverse = reverse
     @regex = new RegExp(pattern)
 
   getRange: (editor, currentRange) ->
-    rangeToSearch = new Range(currentRange.end, editor.getEofPosition())
+    rangeBefore = new Range([0, 0], currentRange.end)
+    rangeAfter = new Range(currentRange.end, editor.getEofPosition())
+
+    rangeToSearch = if @reverse then rangeBefore else rangeAfter
 
     rangeToReturn = null
-    editor.buffer.scanInRange @regex, rangeToSearch, (match, range) ->
+    scanMethodName = if @reverse then "backwardsScanInRange" else "scanInRange"
+    editor[scanMethodName] @regex, rangeToSearch, (match, range) ->
       rangeToReturn = range
 
     if rangeToReturn
       rangeToReturn
     else
-      rangeToSearch = new Range([0, 0], rangeToSearch.start)
-      editor.buffer.scanInRange @regex, rangeToSearch, (match, range) ->
+      rangeToSearch = if @reverse then rangeAfter else rangeBefore
+      editor[scanMethodName] @regex, rangeToSearch, (match, range) ->
         rangeToReturn = range
 
       rangeToReturn or currentRange