Adds a test case for #29

test/crc16.spec.coffee

@@ -1,4 +1,10 @@
 require './test_helpers'
+crc = require '../src/crc16'
 
 describe 'CRC16', ->
-  crcSuiteFor crc: require '../src/crc16'
+  crcSuiteFor {crc}
+
+  # https://github.com/alexgorbatchev/node-crc/issues/29
+  crcSuiteFor
+    crc: crc
+    value: new Buffer('AR0AAAGP2KJc/vg/AAAAErgGAK8dAAgLAQAAPpo=', 'base64').slice(0, 27)

test/mocha.opts

@@ -2,4 +2,4 @@
 --recursive
 --reporter spec
 --ui bdd
---timeout 1000
+--timeout 5000

test/test_helpers.coffee

@@ -1,6 +1,7 @@
 require 'coffee-errors'
 
 path = require 'path'
+fs = require 'fs'
 chai = require 'chai'
 {exec} = require 'child_process'
 
@@ -17,40 +18,72 @@ VALUES = [
 ]
 
 GLOBAL.crcSuiteFor = ({crc, value, expected, initial}) ->
-  getReferenceValue = (model, value, initial, callback) ->
+  getReferenceValueForBuffer = (model, buffer, initial, callback) ->
     return callback null, expected if expected?
+    filename = "#{__dirname}/tmp"
+    fs.writeFileSync filename, buffer
     initial = initial? and "--xor-in=0x#{initial.toString(16)}" or ''
-    exec "#{__dirname}/pycrc/pycrc.py --model=#{model} #{initial} --check-string=\"#{value}\"", (err, reference) ->
+    exec "#{__dirname}/pycrc/pycrc.py --model=#{model} #{initial} --check-file=\"#{filename}\"", (err, reference) ->
+      fs.unlinkSync filename
       callback err, reference?.replace /^0x|\n$/g, ''
 
-  testValue = (value, initial, callback) ->
-    getReferenceValue crc.model, value, initial, (err, reference) ->
+  getReferenceValueForString = (model, string, initial, callback) ->
+    return callback null, expected if expected?
+    initial = initial? and "--xor-in=0x#{initial.toString(16)}" or ''
+    exec "#{__dirname}/pycrc/pycrc.py --model=#{model} #{initial} --check-string=\"#{string}\"", (err, reference) ->
+      callback err, reference?.replace /^0x|\n$/g, ''
+
+  testStringValue = (string, initial, callback) ->
+    getReferenceValueForString crc.model, string, initial, (err, reference) ->
       return done err if err?
-      crc(value, initial).toString(16).should.equal reference
+      crc(string, initial).toString(16).should.equal reference
       callback()
 
-  testSplitValue = (value, initial, callback) ->
+  testBufferValue = (buffer, initial, callback) ->
+    getReferenceValueForBuffer crc.model, buffer, initial, (err, reference) ->
+      return done err if err?
+      crc(buffer, initial).toString(16).should.equal reference
+      callback()
+
+  testStringSplitValue = (value, initial, callback) ->
     middle = value.length / 2
     chunk1 = value.substr 0, middle
     chunk2 = value.substr middle
+    v1 = crc chunk1, initial
+    v2 = crc chunk2, v1
+
+    getReferenceValueForString crc.model, value, initial, (err, reference) ->
+      return callback err if err?
+      v2.toString(16).should.equal reference
+      callback()
+
+  testBufferSplitValue = (value, initial, callback) ->
+    middle = value.length / 2
+    chunk1 = value.slice 0, middle
+    chunk2 = value.slice middle
 
     v1 = crc chunk1, initial
     v2 = crc chunk2, v1
 
-    getReferenceValue crc.model, value, initial, (err, reference) ->
-      return done err if err?
+    getReferenceValueForBuffer crc.model, value, initial, (err, reference) ->
+      return callback err if err?
       v2.toString(16).should.equal reference
       callback()
 
-  if value? and expected?
-    describe "STRING: #{value}", ->
-      it 'should calculate a full checksum', (done) -> testValue value, initial, done
-      it 'should calculate a checksum for multiple data', (done) -> testSplitValue value, initial, done
+  if value?
+    if Buffer.isBuffer value
+      describe "BUFFER: #{value.toString 'base64'}", ->
+        it 'should calculate a full checksum', (done) -> testBufferValue value, initial, done
+        it 'should calculate a checksum for multiple data', (done) -> testBufferSplitValue value, initial, done
+    else
+      describe "STRING: #{value}", ->
+        it 'should calculate a full checksum', (done) -> testStringValue value, initial, done
+        it 'should calculate a checksum for multiple data', (done) -> testStringSplitValue value, initial, done
 
   else
     VALUES.map (value) ->
       describe "STRING: #{value}", ->
-        it 'should calculate a full checksum', (done) -> testValue value, initial, done
-        it 'should calculate a full checksum with initial 0x0', (done) -> testValue value, 0, done
-        it 'should calculate a checksum for multiple data', (done) -> testSplitValue value, initial, done
-        it 'should calculate a checksum for multiple data with initial 0x0', (done) -> testSplitValue value, 0, done
+        it 'should calculate a full checksum', (done) -> testStringValue value, initial, done
+        it 'should calculate a full checksum with initial 0x0', (done) -> testStringValue value, 0, done
+        it 'should calculate a checksum for multiple data', (done) -> testStringSplitValue value, initial, done
+        it 'should calculate a checksum for multiple data with initial 0x0', (done) -> testStringSplitValue value, 0, done