               assert stdout is value+eol
               done()
 
+  it 'unknown algorithm error', (done) ->
+    exec sco + "-e hoge hello", (error, stdout, stderr) ->
+      assert stderr is "Error: unknown algorithm specified"+eol
+      done()
+
 describe 'cli decode test', ->
   for algo, testset of decode_testset
     do (algo, testset) ->

    'YWJj':'abc'


describe 'sco command-line test', ->
  it 'display version if -v option specified', (done) ->
    exec sco + '-v', (error, stdout, stderr) ->
      assert stdout is pack['version']+eol

  it 'display help message if -h option specified', (done) ->
    exec sco + '-h', (error, stdout, stderr) ->
      assert.ok stdout.match('help')
      done()

  it 'list available algorithm if -l enc option specified', (done) ->
    exec sco + "-l enc", (error, stdout, stderr) ->
      assert.ok stdout.match('base64')
      done()

  it 'list available algorithm if -l dec option specified', (done) ->
    exec sco + "-l dec", (error, stdout, stderr) ->
      assert.ok stdout.match('base64')
      done()

describe 'cli encode test', ->
