other minor problems

add magic coding comment
cleanup imports, second part
2025-09-13 09:09:58 +00:00 · 2018-05-16 02:15:52 +02:00 · 2018-05-16 02:02:35 +02:00 · 2018-05-16 01:57:37 +02:00 · 2018-05-16 01:23:04 +02:00 · 2018-05-16 01:09:48 +02:00
57 changed files with 1007 additions and 709 deletions
--- a/.gitignore
+++ b/.gitignore
@@ -20,6 +20,7 @@ dist/
 .coverage
 src/escpos/version.py
 .hypothesis
+.pytest_cache/

 # testing temporary directories
 test/test-cli-output/
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,4 @@
 [submodule "capabilities-data"]
 	path = capabilities-data
 	url = https://github.com/receipt-print-hq/escpos-printer-db.git
+	branch = master
--- a/.mailmap
+++ b/.mailmap
@@ -8,4 +8,7 @@ Cody (Quantified Code Bot) <cody@quantifiedcode.com> Cody <cody@quantifiedcode.c
 Renato Lorenzi <renato.lorenzi@senior.com.br>        Renato.Lorenzi <renato.lorenzi@senior.com.br>
 Ahmed Tahri <nyuubi.10@gmail.com>                    TAHRI Ahmed <nyuubi.10@gmail.com>
 Michael Elsdörfer <michael@elsdoerfer.com>           Michael Elsdörfer <michael@elsdoerfer.info>
-csoft2k <csoft2k@hotmail.com>
+Juanmi Taboada <juanmi@juanmitaboada.com>            Juanmi Taboada <juanmi@juanmitaboada.com>
+csoft2k <csoft2k@hotmail.com>
+Sergio Pulgarin <sergio.pulgarin@gmail.com>
+reck31 <rakesh.gunduka@gmail.com>
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,12 +7,13 @@ addons:
  apt:
    packages:
      - graphviz
+env:
+  global:
+    - ESCPOS_CAPABILITIES_FILE=/home/travis/build/python-escpos/python-escpos/capabilities-data/dist/capabilities.json
 matrix:
  include:
    - python: 2.7
      env: TOXENV=py27
-    - python: 3.3
-      env: TOXENV=py33
    - python: 3.4
      env: TOXENV=py34
    - python: 3.5
@@ -21,6 +22,8 @@ matrix:
      env: TOXENV=py36
    - python: 3.6-dev
      env: TOXENV=py36
+    - python: 3.7-dev
+      env: TOXENV=py37
    - python: nightly
      env: TOXENV=py37
    - python: pypy
@@ -35,6 +38,7 @@ matrix:
      env: TOXENV=flake8
  allow_failures:
    - python: 3.6-dev
+    - python: 3.7-dev
    - python: nightly
    - python: pypy3
 before_install:
@@ -59,4 +63,4 @@ deploy:
      tags: true
      repo: python-escpos/python-escpos
      branch: master
-      condition: $TRAVIS_PYTHON_VERSION = "3.5"
+      condition: $TRAVIS_PYTHON_VERSION = "3.6"
--- a/6
+++ b/6
@@ -10,17 +10,23 @@ Dean Rispin
 Dmytro Katyukha
 Hark
 Joel Lehtonen
+kennedy
 Kristi
 ldos
+Lucy Linder
 Manuel F Martinez
 Michael Billington
 Michael Elsdörfer
+mrwunderbar666
 Nathan Bookham
 Patrick Kanzler
+primax79
 Qian Linfeng
+reck31
 Renato Lorenzi
 Romain Porte
 Sam Cheng
+Sergio Pulgarin
 Stephan Sokolow
 Thijs Triemstra
 Thomas van den Berg
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -1,6 +1,79 @@
 *********
 Changelog
 *********
+2018-05-15 - Version 3.0a4 - "Kakistocrat"
+------------------------------------------
+This release is the fifth alpha release of the new version 3.0. Please
+be aware that the API will still change until v3.0 is released.
+
+changes
+^^^^^^^
+- raise exception when TypeError occurs in cashdraw (#268)
+- Feature/clear content in dummy printer (#271)
+- fix is_online() (#282)
+- improve documentation
+- Modified submodule to always pull from master branch (#283)
+- parameter for implementation of nonnative qrcode (#289)
+- improve platform independence (#296)
+
+contributors
+^^^^^^^^^^^^
+- Christoph Heuel
+- Patrick Kanzler
+- kennedy
+- primax79
+- reck31
+- Thijs Triemstra
+
+2017-10-08 - Version 3.0a3 - "Just Testing"
+-------------------------------------------
+This release is the fourth alpha release of the new version 3.0. Please
+be aware that the API will still change until v3.0 is released.
+
+changes
+^^^^^^^
+- minor changes in documentation, tests and examples
+- pickle capabilities for faster startup
+- first implementation of centering images and QR
+- check barcodes based on regex
+
+contributors
+^^^^^^^^^^^^
+- Patrick Kanzler
+- Lucy Linder
+- Romain Porte
+- Sergio Pulgarin
+
+2017-08-04 - Version 3.0a2 - "It's My Party And I'll Sing If I Want To"
+-----------------------------------------------------------------------
+This release is the third alpha release of the new version 3.0. Please
+be aware that the API will still change until v3.0 is released.
+
+changes
+^^^^^^^
+- refactor of the set-method
+- preliminary support of POS "line display" printing
+- improvement of tests
+- added ImageWidthError
+- list authors in repository
+- add support for software-based barcode-rendering
+- fix SerialException when trying to close device on __del__
+- added the DLE EOT querying command for USB and Serial
+- ensure QR codes have a large enough border
+- make feed for cut optional
+- fix the behavior of horizontal tabs
+- added test script for hard an soft barcodes
+- implemented paper sensor querying command
+- added weather forecast example script
+- added a method for simpler newlines
+
+contributors
+^^^^^^^^^^^^
+- csoft2k
+- Patrick Kanzler
+- mrwunderbar666
+- Romain Porte
+- Ahmed Tahri

 2017-03-29 - Version 3.0a1 - "Headcrash"
 ----------------------------------------
--- a/CONTRIBUTING.rst
+++ b/CONTRIBUTING.rst
@@ -20,6 +20,7 @@ When contributing the first time, please include a commit with the output of thi
 Otherwise the integration-check will fail.

 When you change your username or mail-address, please also update the `.mailmap` and the authors-list.
+You can find a good documentation on the mapping-feature in the `documentation of git-shortlog <https://git-scm.com/docs/git-shortlog#_mapping_authors>`_.

 Style-Guide
 -----------
@@ -47,9 +48,11 @@ Often you can achieve compatibility quite easily with a tool from the `six`-pack

 PEP8
 ^^^^
-This is not yet consequently done in every piece of code, but please try to ensure
-that your code honors PEP8.
-The checks by Landscape and QuantifiedCode that run on every PR will provide you with hints.
+The entire codebase adheres to the rules of PEP8.
+These rules are enforced by running `flake8` in the integration-checks.
+Please adhere to these rules as your contribution can only be merged if the check succeeds.
+You can use flake8 or similar tools locally in order to check your code.
+Apart from that the travis-log and the check by Landscape will provide you with hints.

 GIT
 ^^^
--- a/README.rst
+++ b/README.rst
@@ -6,10 +6,6 @@ python-escpos - Python library to manipulate ESC/POS Printers
    :target: https://travis-ci.org/python-escpos/python-escpos
    :alt: Continous Integration

-.. image:: https://www.quantifiedcode.com/api/v1/project/95748b89a3974700800b85e4ed3d32c4/badge.svg
-    :target: https://www.quantifiedcode.com/app/project/95748b89a3974700800b85e4ed3d32c4
-    :alt: Code issues
-
 .. image:: https://landscape.io/github/python-escpos/python-escpos/master/landscape.svg?style=flat
    :target: https://landscape.io/github/python-escpos/python-escpos/master
    :alt: Code Health
@@ -63,9 +59,9 @@ The basic usage is:
    from escpos.printer import Usb

    """ Seiko Epson Corp. Receipt Printer (EPSON TM-T88III) """
-    p = Usb(0x04b8, 0x0202, 0, profile="TM-T88III")
-    p.text("Hello World\n")
-    p.image("logo.gif")
+    p = Usb(0x04b8, 0x0202, 0, profile='TM-T88III')
+    p.text('Hello World\n')
+    p.image('logo.gif')
    p.barcode('1324354657687', 'EAN13', 64, 2, '', '')
    p.cut()

@@ -74,4 +70,13 @@ The full project-documentation is available on `Read the Docs <https://python-es
 Contributing
 ------------

-This project is open for any contribution! Please see CONTRIBUTING.rst for more information.
+This project is open for any contribution! Please see `CONTRIBUTING.rst <http://python-escpos.readthedocs.io/en/latest/dev/contributing.html>`_ for more information.
+
+
+Disclaimer
+----------
+
+None of the vendors cited in this project agree or endorse any of the patterns or implementations.
+Its names are used only to maintain context.
+
+
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -1,125 +0,0 @@
-environment:
-  global:
-    # SDK v7.0 MSVC Express 2008's SetEnv.cmd script will fail if the
-    # /E:ON and /V:ON options are not enabled in the batch script intepreter
-    # See: http://stackoverflow.com/a/13751649/163740
-    CMD_IN_ENV: "cmd /E:ON /V:ON /C .\\appveyor\\run_with_env.cmd"
-
-  matrix:
-
-    # Python 2.7.10 is the latest version and is not pre-installed.
-
-    - PYTHON: "C:\\Python27.10"
-      PYTHON_VERSION: "2.7.10"
-      PYTHON_ARCH: "32"
-
-    - PYTHON: "C:\\Python27.10-x64"
-      PYTHON_VERSION: "2.7.10"
-      PYTHON_ARCH: "64"
-
-    # Pre-installed Python versions, which Appveyor may upgrade to
-    # a later point release.
-    # See: http://www.appveyor.com/docs/installed-software#python
-
-    - PYTHON: "C:\\Python27"
-      PYTHON_VERSION: "2.7.x" # currently 2.7.9
-      PYTHON_ARCH: "32"
-
-    - PYTHON: "C:\\Python27-x64"
-      PYTHON_VERSION: "2.7.x" # currently 2.7.9
-      PYTHON_ARCH: "64"
-
-    - PYTHON: "C:\\Python33"
-      PYTHON_VERSION: "3.3.x" # currently 3.3.5
-      PYTHON_ARCH: "32"
-
-    - PYTHON: "C:\\Python33-x64"
-      PYTHON_VERSION: "3.3.x" # currently 3.3.5
-      PYTHON_ARCH: "64"
-
-    - PYTHON: "C:\\Python34"
-      PYTHON_VERSION: "3.4.x" # currently 3.4.3
-      PYTHON_ARCH: "32"
-
-    - PYTHON: "C:\\Python34-x64"
-      PYTHON_VERSION: "3.4.x" # currently 3.4.3
-      PYTHON_ARCH: "64"
-
-    # Python versions not pre-installed
-
-    - PYTHON: "C:\\Python35"
-      PYTHON_VERSION: "3.5.0"
-      PYTHON_ARCH: "32"
-
-    - PYTHON: "C:\\Python35-x64"
-      PYTHON_VERSION: "3.5.0"
-      PYTHON_ARCH: "64"
-
-    # Major and minor releases (i.e x.0.0 and x.y.0) prior to 3.3.0 use
-    # a different naming scheme.
-
-    - PYTHON: "C:\\Python270"
-      PYTHON_VERSION: "2.7.0"
-      PYTHON_ARCH: "32"
-
-    - PYTHON: "C:\\Python270-x64"
-      PYTHON_VERSION: "2.7.0"
-      PYTHON_ARCH: "64"
-
-install:
-  # If there is a newer build queued for the same PR, cancel this one.
-  # The AppVeyor 'rollout builds' option is supposed to serve the same
-  # purpose but it is problematic because it tends to cancel builds pushed
-  # directly to master instead of just PR builds (or the converse).
-  # credits: JuliaLang developers.
-  - ps: if ($env:APPVEYOR_PULL_REQUEST_NUMBER -and $env:APPVEYOR_BUILD_NUMBER -ne ((Invoke-RestMethod `
-        https://ci.appveyor.com/api/projects/$env:APPVEYOR_ACCOUNT_NAME/$env:APPVEYOR_PROJECT_SLUG/history?recordsNumber=50).builds | `
-        Where-Object pullRequestId -eq $env:APPVEYOR_PULL_REQUEST_NUMBER)[0].buildNumber) { `
-          throw "There are newer queued builds for this pull request, failing early." }
-  - ECHO "Filesystem root:"
-  - ps: "ls \"C:/\""
-
-  - ECHO "Installed SDKs:"
-  - ps: "ls \"C:/Program Files/Microsoft SDKs/Windows\""
-
-  # Install Python (from the official .msi of http://python.org) and pip when
-  # not already installed.
-  - ps: if (-not(Test-Path($env:PYTHON))) { & appveyor\install.ps1 }
-
-  # Prepend newly installed Python to the PATH of this build (this cannot be
-  # done from inside the powershell script as it would require to restart
-  # the parent CMD process).
-  - "SET PATH=%PYTHON%;%PYTHON%\\Scripts;%PATH%"
-
-  # Check that we have the expected version and architecture for Python
-  - "python --version"
-  - "python -c \"import struct; print(struct.calcsize('P') * 8)\""
-
-  # Upgrade to the latest version of pip to avoid it displaying warnings
-  # about it being out of date.
-  - "pip install --disable-pip-version-check --user --upgrade pip"
-
-  # Install the build dependencies of the project. If some dependencies contain
-  # compiled extensions and are not provided as pre-built wheel packages,
-  # pip will build them from source using the MSVC compiler matching the
-  # target Python version and architecture
-  - "%CMD_IN_ENV% pip install -r requirements.txt"
-
-build_script:
-  # Build the compiled extension
-  - "%CMD_IN_ENV% python setup.py build"
-
-test_script:
-  # Run the project tests
-  - "%CMD_IN_ENV% python setup.py test"
-
-after_test:
-  # If tests are successful, create binary packages for the project.
-  - "%CMD_IN_ENV% python setup.py bdist_wheel"
-  - "%CMD_IN_ENV% python setup.py bdist_wininst"
-  - "%CMD_IN_ENV% python setup.py bdist_msi"
-  - ps: "ls dist"
-
-artifacts:
-  # Archive the generated packages in the ci.appveyor.com build report.
-  - path: dist\*
--- a/appveyor/install.ps1
+++ b/appveyor/install.ps1
@@ -1,229 +0,0 @@
-# Sample script to install Python and pip under Windows
-# Authors: Olivier Grisel, Jonathan Helmus, Kyle Kastner, and Alex Willmer
-# License: CC0 1.0 Universal: http://creativecommons.org/publicdomain/zero/1.0/
-
-$MINICONDA_URL = "http://repo.continuum.io/miniconda/"
-$BASE_URL = "https://www.python.org/ftp/python/"
-$GET_PIP_URL = "https://bootstrap.pypa.io/get-pip.py"
-$GET_PIP_PATH = "C:\get-pip.py"
-
-$PYTHON_PRERELEASE_REGEX = @"
-(?x)
-(?<major>\d+)
-\.
-(?<minor>\d+)
-\.
-(?<micro>\d+)
-(?<prerelease>[a-z]{1,2}\d+)
-"@
-
-
-function Download ($filename, $url) {
-    $webclient = New-Object System.Net.WebClient
-
-    $basedir = $pwd.Path + "\"
-    $filepath = $basedir + $filename
-    if (Test-Path $filename) {
-        Write-Host "Reusing" $filepath
-        return $filepath
-    }
-
-    # Download and retry up to 3 times in case of network transient errors.
-    Write-Host "Downloading" $filename "from" $url
-    $retry_attempts = 2
-    for ($i = 0; $i -lt $retry_attempts; $i++) {
-        try {
-            $webclient.DownloadFile($url, $filepath)
-            break
-        }
-        Catch [Exception]{
-            Start-Sleep 1
-        }
-    }
-    if (Test-Path $filepath) {
-        Write-Host "File saved at" $filepath
-    } else {
-        # Retry once to get the error message if any at the last try
-        $webclient.DownloadFile($url, $filepath)
-    }
-    return $filepath
-}
-
-
-function ParsePythonVersion ($python_version) {
-    if ($python_version -match $PYTHON_PRERELEASE_REGEX) {
-        return ([int]$matches.major, [int]$matches.minor, [int]$matches.micro,
-                $matches.prerelease)
-    }
-    $version_obj = [version]$python_version
-    return ($version_obj.major, $version_obj.minor, $version_obj.build, "")
-}
-
-
-function DownloadPython ($python_version, $platform_suffix) {
-    $major, $minor, $micro, $prerelease = ParsePythonVersion $python_version
-
-    if (($major -le 2 -and $micro -eq 0) `
-        -or ($major -eq 3 -and $minor -le 2 -and $micro -eq 0) `
-        ) {
-        $dir = "$major.$minor"
-        $python_version = "$major.$minor$prerelease"
-    } else {
-        $dir = "$major.$minor.$micro"
-    }
-
-    if ($prerelease) {
-        if (($major -le 2) `
-            -or ($major -eq 3 -and $minor -eq 1) `
-            -or ($major -eq 3 -and $minor -eq 2) `
-            -or ($major -eq 3 -and $minor -eq 3) `
-            ) {
-            $dir = "$dir/prev"
-        }
-    }
-
-    if (($major -le 2) -or ($major -le 3 -and $minor -le 4)) {
-        $ext = "msi"
-        if ($platform_suffix) {
-            $platform_suffix = ".$platform_suffix"
-        }
-    } else {
-        $ext = "exe"
-        if ($platform_suffix) {
-            $platform_suffix = "-$platform_suffix"
-        }
-    }
-
-    $filename = "python-$python_version$platform_suffix.$ext"
-    $url = "$BASE_URL$dir/$filename"
-    $filepath = Download $filename $url
-    return $filepath
-}
-
-
-function InstallPython ($python_version, $architecture, $python_home) {
-    Write-Host "Installing Python" $python_version "for" $architecture "bit architecture to" $python_home
-    if (Test-Path $python_home) {
-        Write-Host $python_home "already exists, skipping."
-        return $false
-    }
-    if ($architecture -eq "32") {
-        $platform_suffix = ""
-    } else {
-        $platform_suffix = "amd64"
-    }
-    $installer_path = DownloadPython $python_version $platform_suffix
-    $installer_ext = [System.IO.Path]::GetExtension($installer_path)
-    Write-Host "Installing $installer_path to $python_home"
-    $install_log = $python_home + ".log"
-    if ($installer_ext -eq '.msi') {
-        InstallPythonMSI $installer_path $python_home $install_log
-    } else {
-        InstallPythonEXE $installer_path $python_home $install_log
-    }
-    if (Test-Path $python_home) {
-        Write-Host "Python $python_version ($architecture) installation complete"
-    } else {
-        Write-Host "Failed to install Python in $python_home"
-        Get-Content -Path $install_log
-        Exit 1
-    }
-}
-
-
-function InstallPythonEXE ($exepath, $python_home, $install_log) {
-    $install_args = "/quiet InstallAllUsers=1 TargetDir=$python_home"
-    RunCommand $exepath $install_args
-}
-
-
-function InstallPythonMSI ($msipath, $python_home, $install_log) {
-    $install_args = "/qn /log $install_log /i $msipath TARGETDIR=$python_home"
-    $uninstall_args = "/qn /x $msipath"
-    RunCommand "msiexec.exe" $install_args
-    if (-not(Test-Path $python_home)) {
-        Write-Host "Python seems to be installed else-where, reinstalling."
-        RunCommand "msiexec.exe" $uninstall_args
-        RunCommand "msiexec.exe" $install_args
-    }
-}
-
-function RunCommand ($command, $command_args) {
-    Write-Host $command $command_args
-    Start-Process -FilePath $command -ArgumentList $command_args -Wait -Passthru
-}
-
-
-function InstallPip ($python_home) {
-    $pip_path = $python_home + "\Scripts\pip.exe"
-    $python_path = $python_home + "\python.exe"
-    if (-not(Test-Path $pip_path)) {
-        Write-Host "Installing pip..."
-        $webclient = New-Object System.Net.WebClient
-        $webclient.DownloadFile($GET_PIP_URL, $GET_PIP_PATH)
-        Write-Host "Executing:" $python_path $GET_PIP_PATH
-        & $python_path $GET_PIP_PATH
-    } else {
-        Write-Host "pip already installed."
-    }
-}
-
-
-function DownloadMiniconda ($python_version, $platform_suffix) {
-    if ($python_version -eq "3.4") {
-        $filename = "Miniconda3-3.5.5-Windows-" + $platform_suffix + ".exe"
-    } else {
-        $filename = "Miniconda-3.5.5-Windows-" + $platform_suffix + ".exe"
-    }
-    $url = $MINICONDA_URL + $filename
-    $filepath = Download $filename $url
-    return $filepath
-}
-
-
-function InstallMiniconda ($python_version, $architecture, $python_home) {
-    Write-Host "Installing Python" $python_version "for" $architecture "bit architecture to" $python_home
-    if (Test-Path $python_home) {
-        Write-Host $python_home "already exists, skipping."
-        return $false
-    }
-    if ($architecture -eq "32") {
-        $platform_suffix = "x86"
-    } else {
-        $platform_suffix = "x86_64"
-    }
-    $filepath = DownloadMiniconda $python_version $platform_suffix
-    Write-Host "Installing" $filepath "to" $python_home
-    $install_log = $python_home + ".log"
-    $args = "/S /D=$python_home"
-    Write-Host $filepath $args
-    Start-Process -FilePath $filepath -ArgumentList $args -Wait -Passthru
-    if (Test-Path $python_home) {
-        Write-Host "Python $python_version ($architecture) installation complete"
-    } else {
-        Write-Host "Failed to install Python in $python_home"
-        Get-Content -Path $install_log
-        Exit 1
-    }
-}
-
-
-function InstallMinicondaPip ($python_home) {
-    $pip_path = $python_home + "\Scripts\pip.exe"
-    $conda_path = $python_home + "\Scripts\conda.exe"
-    if (-not(Test-Path $pip_path)) {
-        Write-Host "Installing pip..."
-        $args = "install --yes pip"
-        Write-Host $conda_path $args
-        Start-Process -FilePath "$conda_path" -ArgumentList $args -Wait -Passthru
-    } else {
-        Write-Host "pip already installed."
-    }
-}
-
-function main () {
-    InstallPython $env:PYTHON_VERSION $env:PYTHON_ARCH $env:PYTHON
-    InstallPip $env:PYTHON
-}
-
-main
--- a/appveyor/run_with_env.cmd
+++ b/appveyor/run_with_env.cmd
@@ -1,88 +0,0 @@
-:: To build extensions for 64 bit Python 3, we need to configure environment
-:: variables to use the MSVC 2010 C++ compilers from GRMSDKX_EN_DVD.iso of:
-:: MS Windows SDK for Windows 7 and .NET Framework 4 (SDK v7.1)
-::
-:: To build extensions for 64 bit Python 2, we need to configure environment
-:: variables to use the MSVC 2008 C++ compilers from GRMSDKX_EN_DVD.iso of:
-:: MS Windows SDK for Windows 7 and .NET Framework 3.5 (SDK v7.0)
-::
-:: 32 bit builds, and 64-bit builds for 3.5 and beyond, do not require specific
-:: environment configurations.
-::
-:: Note: this script needs to be run with the /E:ON and /V:ON flags for the
-:: cmd interpreter, at least for (SDK v7.0)
-::
-:: More details at:
-:: https://github.com/cython/cython/wiki/64BitCythonExtensionsOnWindows
-:: http://stackoverflow.com/a/13751649/163740
-::
-:: Author: Olivier Grisel
-:: License: CC0 1.0 Universal: http://creativecommons.org/publicdomain/zero/1.0/
-::
-:: Notes about batch files for Python people:
-::
-:: Quotes in values are literally part of the values:
-::      SET FOO="bar"
-:: FOO is now five characters long: " b a r "
-:: If you don't want quotes, don't include them on the right-hand side.
-::
-:: The CALL lines at the end of this file look redundant, but if you move them
-:: outside of the IF clauses, they do not run properly in the SET_SDK_64==Y
-:: case, I don't know why.
-@ECHO OFF
-
-SET COMMAND_TO_RUN=%*
-SET WIN_SDK_ROOT=C:\Program Files\Microsoft SDKs\Windows
-SET WIN_WDK=c:\Program Files (x86)\Windows Kits\10\Include\wdf
-
-:: Extract the major and minor versions, and allow for the minor version to be
-:: more than 9.  This requires the version number to have two dots in it.
-SET MAJOR_PYTHON_VERSION=%PYTHON_VERSION:~0,1%
-IF "%PYTHON_VERSION:~3,1%" == "." (
-    SET MINOR_PYTHON_VERSION=%PYTHON_VERSION:~2,1%
-) ELSE (
-    SET MINOR_PYTHON_VERSION=%PYTHON_VERSION:~2,2%
-)
-
-:: Based on the Python version, determine what SDK version to use, and whether
-:: to set the SDK for 64-bit.
-IF %MAJOR_PYTHON_VERSION% == 2 (
-    SET WINDOWS_SDK_VERSION="v7.0"
-    SET SET_SDK_64=Y
-) ELSE (
-    IF %MAJOR_PYTHON_VERSION% == 3 (
-        SET WINDOWS_SDK_VERSION="v7.1"
-        IF %MINOR_PYTHON_VERSION% LEQ 4 (
-            SET SET_SDK_64=Y
-        ) ELSE (
-            SET SET_SDK_64=N
-            IF EXIST "%WIN_WDK%" (
-                :: See: https://connect.microsoft.com/VisualStudio/feedback/details/1610302/
-                REN "%WIN_WDK%" 0wdf
-            )
-        )
-    ) ELSE (
-        ECHO Unsupported Python version: "%MAJOR_PYTHON_VERSION%"
-        EXIT 1
-    )
-)
-
-IF %PYTHON_ARCH% == 64 (
-    IF %SET_SDK_64% == Y (
-        ECHO Configuring Windows SDK %WINDOWS_SDK_VERSION% for Python %MAJOR_PYTHON_VERSION% on a 64 bit architecture
-        SET DISTUTILS_USE_SDK=1
-        SET MSSdk=1
-        "%WIN_SDK_ROOT%\%WINDOWS_SDK_VERSION%\Setup\WindowsSdkVer.exe" -q -version:%WINDOWS_SDK_VERSION%
-        "%WIN_SDK_ROOT%\%WINDOWS_SDK_VERSION%\Bin\SetEnv.cmd" /x64 /release
-        ECHO Executing: %COMMAND_TO_RUN%
-        call %COMMAND_TO_RUN% || EXIT 1
-    ) ELSE (
-        ECHO Using default MSVC build environment for 64 bit architecture
-        ECHO Executing: %COMMAND_TO_RUN%
-        call %COMMAND_TO_RUN% || EXIT 1
-    )
-) ELSE (
-    ECHO Using default MSVC build environment for 32 bit architecture
-    ECHO Executing: %COMMAND_TO_RUN%
-    call %COMMAND_TO_RUN% || EXIT 1
-)
--- a/2
+++ b/2
--- a/doc/generate_authors.sh
+++ b/doc/generate_authors.sh
@@ -1,6 +1,6 @@
 #!/bin/sh

-GENLIST=$(git shortlog -s -n | cut -f2 | sort)
+GENLIST=$(git shortlog -s -n | cut -f2 | sort -f)
 AUTHORSFILE="$(dirname $0)/../AUTHORS"
 TEMPAUTHORSFILE="/tmp/python-escpos-authorsfile"

--- a/doc/requirements.txt
+++ b/doc/requirements.txt
@@ -5,3 +5,4 @@ pyserial
 sphinx-rtd-theme
 setuptools-scm
 docutils>=0.12
+viivakoodi
--- a/doc/user/usage.rst
+++ b/doc/user/usage.rst
@@ -67,7 +67,7 @@ IP by DHCP or you set it manually.

 ::

-    Epson = printer.Network("192.168.1.99")
+    Epson = printer.Network('192.168.1.99')

 Serial printer
 ^^^^^^^^^^^^^^
@@ -81,7 +81,7 @@ to.

 ::

-    Epson = printer.Serial("/dev/tty0")
+    Epson = printer.Serial('/dev/tty0')

 Other printers
 ^^^^^^^^^^^^^^
@@ -93,7 +93,7 @@ passing the device node name.

 ::

-    Epson = printer.File("/dev/usb/lp1")
+    Epson = printer.File('/dev/usb/lp1')

 The default is "/dev/usb/lp0", so if the printer is located on that
 node, then you don't necessary need to pass the node name.
@@ -110,11 +110,11 @@ on a USB interface.
    """ Seiko Epson Corp. Receipt Printer M129 Definitions (EPSON TM-T88IV) """
    Epson = printer.Usb(0x04b8,0x0202)
    # Print text
-    Epson.text("Hello World\n")
+    Epson.text('Hello World\n')
    # Print image
-    Epson.image("logo.gif")
+    Epson.image('logo.gif')
    # Print QR Code
-    Epson.qr("You can readme from your smartphone")
+    Epson.qr('You can readme from your smartphone')
    # Print barcode
    Epson.barcode('1324354657687','EAN13',64,2,'','')
    # Cut paper
@@ -214,7 +214,7 @@ advantage of the fact that `_raw()` accepts binary strings.)
    from escpos import printer
    p = printer.Serial()  # adapt this to your printer model

-    file = open("binary-blob.bin", "rb")  # read in the file containing your commands in binary-mode
+    file = open('binary-blob.bin', 'rb')  # read in the file containing your commands in binary-mode
    data = file.read()
    file.close()

@@ -273,8 +273,8 @@ This is probably best explained by an example:
   d = Dummy()

   # create ESC/POS for the print job, this should go really fast
-   d.text("This is my image:\n")
-   d.image("funny_cat.png")
+   d.text('This is my image:\n')
+   d.image('funny_cat.png')
   d.cut()

   # send code to printer
--- a/examples/barcodes.py
+++ b/examples/barcodes.py
@@ -0,0 +1,17 @@
+#  -*- coding: utf-8 -*-
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+from __future__ import unicode_literals
+
+from escpos.printer import Usb
+
+
+# Adapt to your needs
+p = Usb(0x0416, 0x5011, profile='POS-5890')
+
+# Print software and then hardware barcode with the same content
+p.soft_barcode('code39', '123456')
+p.text('\n')
+p.text('\n')
+p.barcode('123456', 'CODE39')
--- a/examples/codepage_tables.py
+++ b/examples/codepage_tables.py
@@ -1,13 +1,17 @@
+#  -*- coding: utf-8 -*-
 """Prints code page tables.
 """
-
+from __future__ import absolute_import
+from __future__ import division
 from __future__ import print_function
+from __future__ import unicode_literals

-import six
 import sys

 from escpos import printer
-from escpos.constants import CODEPAGE_CHANGE, ESC, CTL_LF, CTL_FF, CTL_CR, CTL_HT, CTL_VT
+from escpos.constants import CODEPAGE_CHANGE, CTL_CR, CTL_FF, CTL_HT, CTL_LF, CTL_VT, ESC
+
+import six


 def main():
@@ -17,9 +21,9 @@ def main():

    for codepage in sys.argv[1:] or ['USA']:
        dummy.set(height=2, width=2)
-        dummy._raw(codepage + "\n\n\n")
+        dummy._raw(codepage + '\n\n\n')
        print_codepage(dummy, codepage)
-        dummy._raw("\n\n")
+        dummy._raw('\n\n')

    dummy.cut()

@@ -30,22 +34,22 @@ def print_codepage(printer, codepage):
    if codepage.isdigit():
        codepage = int(codepage)
        printer._raw(CODEPAGE_CHANGE + six.int2byte(codepage))
-        printer._raw("after")
+        printer._raw('after')
    else:
        printer.charcode(codepage)

-    sep = ""
+    sep = ''

    # Table header
-    printer.set(text_type='B')
-    printer._raw("  {}\n".format(sep.join(map(lambda s: hex(s)[2:], range(0, 16)))))
+    printer.set(font='b')
+    printer._raw('  {}\n'.format(sep.join(map(lambda s: hex(s)[2:], range(0, 16)))))
    printer.set()

    # The table
    for x in range(0, 16):
        # First column
-        printer.set(text_type='B')
-        printer._raw("{} ".format(hex(x)[2:]))
+        printer.set(font='b')
+        printer._raw('{} '.format(hex(x)[2:]))
        printer.set()

        for y in range(0, 16):
--- a/examples/graphics/climacons/clear-day.png
+++ b/examples/graphics/climacons/clear-day.png
--- a/examples/graphics/climacons/clear-night.png
+++ b/examples/graphics/climacons/clear-night.png
--- a/examples/graphics/climacons/cloudy.png
+++ b/examples/graphics/climacons/cloudy.png
--- a/examples/graphics/climacons/fog.png
+++ b/examples/graphics/climacons/fog.png
--- a/examples/graphics/climacons/partly-cloudy-day.png
+++ b/examples/graphics/climacons/partly-cloudy-day.png
--- a/examples/graphics/climacons/partly-cloudy-night.png
+++ b/examples/graphics/climacons/partly-cloudy-night.png
--- a/examples/graphics/climacons/rain.png
+++ b/examples/graphics/climacons/rain.png
--- a/examples/graphics/climacons/readme.md
+++ b/examples/graphics/climacons/readme.md
@@ -0,0 +1,10 @@
+# Climacons by Adam Whitcroft
+
+75 climatically categorised pictographs for web and UI design by [@adamwhitcroft](http://www.twitter.com/#!/adamwhitcroft).
+
+Visit the [Climacons](http://adamwhitcroft.com/climacons/) website for more information.
+
+Visit [Adam Whitcroft on GitHub](https://github.com/AdamWhitcroft)
+
+## License
+You are free to use any of the Climacons Icons (the "icons") in any personal or commercial work without obligation of payment (monetary or otherwise) or attribution, however a credit for the work would be appreciated. **Do not** redistribute or sell and **do not** claim creative credit. Intellectual property rights are not transferred with the download of the icons.
--- a/examples/graphics/climacons/sleet.png
+++ b/examples/graphics/climacons/sleet.png
--- a/examples/graphics/climacons/snow.png
+++ b/examples/graphics/climacons/snow.png
--- a/examples/graphics/climacons/wind.png
+++ b/examples/graphics/climacons/wind.png
--- a/examples/qr_code.py
+++ b/examples/qr_code.py
@@ -1,10 +1,16 @@
+#  -*- coding: utf-8 -*-
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+from __future__ import unicode_literals
+
 import sys

 from escpos.printer import Usb


 def usage():
-    print("usage: qr_code.py <content>")
+    print('usage: qr_code.py <content>')


 if __name__ == '__main__':
@@ -15,5 +21,5 @@ if __name__ == '__main__':
    content = sys.argv[1]

    # Adapt to your needs
-    p = Usb(0x0416, 0x5011, profile="POS-5890")
-    p.qr(content)
+    p = Usb(0x0416, 0x5011, profile='POS-5890')
+    p.qr(content, center=True)
--- a/examples/software_barcode.py
+++ b/examples/software_barcode.py
@@ -1,8 +1,14 @@
+#  -*- coding: utf-8 -*-
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+from __future__ import unicode_literals
+
 from escpos.printer import Usb


 # Adapt to your needs
-p = Usb(0x0416, 0x5011, profile="POS-5890")
+p = Usb(0x0416, 0x5011, profile='POS-5890')

 # Some software barcodes
 p.soft_barcode('code128', 'Hello')
--- a/examples/weather.py
+++ b/examples/weather.py
@@ -0,0 +1,130 @@
+#!/usr/bin/env python
+#  -*- coding: utf-8 -*-
+
+# Adapted script from Adafruit
+# Weather forecast for Raspberry Pi w/Adafruit Mini Thermal Printer.
+# Retrieves data from DarkSky.net's API, prints current conditions and
+# forecasts for next two days.
+# Weather example using nice bitmaps.
+# Written by Adafruit Industries.  MIT license.
+# Adapted and enhanced for escpos library by MrWunderbar666
+
+# Icons taken from http://adamwhitcroft.com/climacons/
+# Check out his github: https://github.com/AdamWhitcroft/climacons
+
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+from __future__ import unicode_literals
+
+import calendar
+import json
+import os
+import time
+import urllib
+from datetime import datetime
+
+from escpos.printer import Usb
+
+""" Setting up the main pathing """
+this_dir, this_filename = os.path.split(__file__)
+GRAPHICS_PATH = os.path.join(this_dir, 'graphics/climacons/')
+
+# Adapt to your needs
+printer = Usb(0x0416, 0x5011, profile='POS-5890')
+
+# You can get your API Key on www.darksky.net and register a dev account.
+# Technically you can use any other weather service, of course :)
+API_KEY = 'YOUR API KEY'
+
+LAT = '22.345490'       # Your Location
+LONG = '114.189945'     # Your Location
+
+
+def forecast_icon(idx):
+    icon = data['daily']['data'][idx]['icon']
+    image = GRAPHICS_PATH + icon + '.png'
+    return image
+
+
+# Dumps one forecast line to the printer
+def forecast(idx):
+    date = datetime.fromtimestamp(int(data['daily']['data'][idx]['time']))
+    day = calendar.day_name[date.weekday()]
+    lo = data['daily']['data'][idx]['temperatureMin']
+    hi = data['daily']['data'][idx]['temperatureMax']
+    cond = data['daily']['data'][idx]['summary']
+    print(date)
+    print(day)
+    print(lo)
+    print(hi)
+    print(cond)
+    time.sleep(1)
+    printer.set(
+        font='a',
+        height=2,
+        align='left',
+        bold=False,
+        double_height=False)
+    printer.text(day + ' \n ')
+    time.sleep(5)           # Sleep to prevent printer buffer overflow
+    printer.text('\n')
+    printer.image(forecast_icon(idx))
+    printer.text('low ' + str(lo))
+    printer.text(deg)
+    printer.text('\n')
+    printer.text(' high ' + str(hi))
+    printer.text(deg)
+    printer.text('\n')
+    # take care of pesky unicode dash
+    printer.text(cond.replace(u'\u2013', '-').encode('utf-8'))
+    printer.text('\n \n')
+
+
+def icon():
+    icon = data['currently']['icon']
+    image = GRAPHICS_PATH + icon + '.png'
+    return image
+
+
+deg = ' C'      # Degree symbol on thermal printer, need to find a better way to use a proper degree symbol
+
+# if you want Fahrenheit change units= to 'us'
+url = 'https://api.darksky.net/forecast/' + API_KEY + '/' + LAT + ',' + LONG + \
+    '?exclude=[alerts,minutely,hourly,flags]&units=si'  # change last bit to 'us' for Fahrenheit
+response = urllib.urlopen(url)
+data = json.loads(response.read())
+
+printer.print_and_feed(n=1)
+printer.control('LF')
+printer.set(font='a', height=2, align='center', bold=True, double_height=True)
+printer.text('Weather Forecast')
+printer.text('\n')
+printer.set(align='center')
+
+
+# Print current conditions
+printer.set(font='a', height=2, align='center', bold=True, double_height=False)
+printer.text('Current conditions: \n')
+printer.image(icon())
+printer.text('\n')
+
+printer.set(font='a', height=2, align='left', bold=False, double_height=False)
+temp = data['currently']['temperature']
+cond = data['currently']['summary']
+printer.text(temp)
+printer.text(' ')
+printer.text(deg)
+printer.text(' ')
+printer.text('\n')
+printer.text('Sky: ' + cond)
+printer.text('\n')
+printer.text('\n')
+
+# Print forecast
+printer.set(font='a', height=2, align='center', bold=True, double_height=False)
+printer.text('Forecast: \n')
+forecast(0)
+forecast(1)
+printer.cut()
+printer.control('LF')
--- a/setup.cfg
+++ b/setup.cfg
@@ -9,4 +9,13 @@ universal=1
 [flake8]
 exclude = .git,.tox,.github,.eggs,__pycache__,doc/conf.py,build,dist,capabilities-data,test,src/escpos/constants.py
 max-line-length = 120
-# future-imports = absolute_import, division, print_function, unicode_literals  # we are not there yet
+accept-encoding = utf-8, utf-16
+require-code = True
+# FI12 __future__ import "with_statement" missing
+# FI15 __future__ import "generator_stop" missing
+# FI16 __future__ import "nested_scopes" missing
+# FI17 __future__ import "generators" missing
+# FI5x __future__ import "xxx" present
+# I101 Imported names are in the wrong order.
+ignore = FI12,FI15,FI16,FI17,FI5, I101
+copyright-check = True
--- a/setup.py
+++ b/setup.py
@@ -1,13 +1,19 @@
 #!/usr/bin/env python
+#  -*- coding: utf-8 -*-
+
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+# from __future__ import unicode_literals

 import os
 import sys
+
 from setuptools import find_packages, setup
-from setuptools.command.test import test as test_command


 base_dir = os.path.dirname(__file__)
-src_dir = os.path.join(base_dir, "src")
+src_dir = os.path.join(base_dir, 'src')

 # When executing the setup.py, we need to be able to import ourselves, this
 # means that we need to add the src/ directory to the sys.path.
@@ -19,33 +25,6 @@ def read(fname):
    return open(os.path.join(os.path.dirname(__file__), fname)).read()


-class Tox(test_command):
-    """proxy class that enables tox to be run with setup.py test"""
-    user_options = [('tox-args=', 'a', "Arguments to pass to tox")]
-
-    def initialize_options(self):
-        """initialize the user-options"""
-        test_command.initialize_options(self)
-        self.tox_args = None
-
-    def finalize_options(self):
-        """finalize user-options"""
-        test_command.finalize_options(self)
-        self.test_args = []
-        self.test_suite = True
-
-    def run_tests(self):
-        """run tox and pass on user-options"""
-        # import here, cause outside the eggs aren't loaded
-        import tox
-        import shlex
-        args = self.tox_args
-        if args:
-            args = shlex.split(self.tox_args)
-        errno = tox.cmdline(args=args)
-        sys.exit(errno)
-
-
 setuptools_scm_template = """\
 # coding: utf-8
 # file generated by setuptools_scm
@@ -68,7 +47,6 @@ setup(
    url='https://github.com/python-escpos/python-escpos',
    download_url='https://github.com/python-escpos/python-escpos/archive/master.zip',
    description='Python library to manipulate ESC/POS Printers',
-    bugtrack_url='https://github.com/python-escpos/python-escpos/issues',
    license='MIT',
    long_description=read('README.rst'),
    author='Manuel F Martinez and others',
@@ -83,8 +61,8 @@ setup(
        'receipt,',
    ],
    platforms='any',
-    package_dir={"": "src"},
-    packages=find_packages(where="src", exclude=["tests", "tests.*"]),
+    package_dir={'': 'src'},
+    packages=find_packages(where='src', exclude=['tests', 'tests.*']),
    package_data={'': ['COPYING', 'src/escpos/capabilities.json']},
    include_package_data=True,
    classifiers=[
@@ -97,7 +75,6 @@ setup(
        'Programming Language :: Python :: 2',
        'Programming Language :: Python :: 2.7',
        'Programming Language :: Python :: 3',
-        'Programming Language :: Python :: 3.3',
        'Programming Language :: Python :: 3.4',
        'Programming Language :: Python :: 3.5',
        'Programming Language :: Python :: 3.6',
@@ -114,7 +91,7 @@ setup(
        'pyserial',
        'six',
        'appdirs',
-        'pyyaml',
+        'PyYAML',
        'argparse',
        'argcomplete',
        'future',
@@ -126,16 +103,15 @@ setup(
    tests_require=[
        'jaconv',
        'tox',
-        'pytest',
+        'pytest!=3.2.0,!=3.3.0',
        'pytest-cov',
        'pytest-mock',
        'nose',
        'scripttest',
        'mock',
-        'hypothesis',
+        'hypothesis!=3.56.9',
        'flake8'
    ],
-    cmdclass={'test': Tox},
    entry_points={
        'console_scripts': [
            'python-escpos = escpos.cli:main'
--- a/src/escpos/init.py
+++ b/src/escpos/init.py
@@ -7,7 +7,7 @@ from __future__ import division
 from __future__ import print_function
 from __future__ import unicode_literals

-__all__ = ["constants", "escpos", "exceptions", "printer"]
+__all__ = ['constants', 'escpos', 'exceptions', 'printer']

 try:
    from .version import version as __version__  # noqa
--- a/src/escpos/capabilities.py
+++ b/src/escpos/capabilities.py
@@ -1,22 +1,62 @@
+#!/usr/bin/env python
+#  -*- coding: utf-8 -*-
+
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+from __future__ import unicode_literals
+
+import logging
+import pickle
+import platform
 import re
-import six
+import time
 from os import environ, path
+from tempfile import gettempdir
+
+import six
+
 import yaml

-# Load external printer database
-if 'ESCPOS_CAPABILITIES_FILE' in environ:
-    file_path = environ['ESCPOS_CAPABILITIES_FILE']
-else:
-    file_path = path.join(path.dirname(__file__), 'capabilities.json')
+logging.basicConfig()
+logger = logging.getLogger(__name__)
+
+pickle_dir = environ.get('ESCPOS_CAPABILITIES_PICKLE_DIR', gettempdir())
+pickle_path = path.join(pickle_dir, '{v}.capabilities.pickle'.format(v=platform.python_version()))
+capabilities_path = environ.get(
+    'ESCPOS_CAPABILITIES_FILE',
+    path.join(path.dirname(__file__), 'capabilities.json'))
+
+# Load external printer database
+t0 = time.time()
+logger.debug('Using capabilities from file: %s', capabilities_path)
+if path.exists(pickle_path):
+    if path.getmtime(capabilities_path) > path.getmtime(pickle_path):
+        logger.debug('Found a more recent capabilities file')
+        full_load = True
+    else:
+        full_load = False
+        logger.debug('Loading capabilities from pickle in %s', pickle_path)
+        with open(pickle_path, 'rb') as cf:
+            CAPABILITIES = pickle.load(cf)
+else:
+    logger.debug('Capabilities pickle file not found: %s', pickle_path)
+    full_load = True
+
+if full_load:
+    logger.debug('Loading and pickling capabilities')
+    with open(capabilities_path) as cp, open(pickle_path, 'wb') as pp:
+        CAPABILITIES = yaml.load(cp)
+        pickle.dump(CAPABILITIES, pp, protocol=2)
+
+logger.debug('Finished loading capabilities took %.2fs', time.time() - t0)

-with open(file_path) as f:
-    CAPABILITIES = yaml.load(f)

 PROFILES = CAPABILITIES['profiles']


 class NotSupported(Exception):
-    """Raised if a requested feature is not suppored by the
+    """Raised if a requested feature is not supported by the
    printer profile.
    """
    pass
@@ -59,7 +99,7 @@ class BaseProfile(object):
        return self.features.get(feature)

    def get_code_pages(self):
-        """Return the support code pages as a {name: index} dict.
+        """Return the support code pages as a ``{name: index}`` dict.
        """
        return {v: k for k, v in self.codePages.items()}

--- a/src/escpos/cli.py
+++ b/src/escpos/cli.py
@@ -1,4 +1,5 @@
 #!/usr/bin/env python
+#  -*- coding: utf-8 -*-
 # PYTHON_ARGCOMPLETE_OK
 """ CLI

@@ -15,13 +16,15 @@ from __future__ import print_function
 from __future__ import unicode_literals

 import argparse
+import sys
+
 try:
    import argcomplete
 except ImportError:
    # this CLI works nevertheless without argcomplete
    pass  # noqa
-import sys
 import six
+
 from . import config
 from . import version

@@ -550,7 +553,7 @@ def main():
        # print command with args
        getattr(printer, target_command)(**command_arguments)
        if target_command in REQUIRES_NEWLINE:
-            printer.text("\n")
+            printer.text('\n')
    else:
        command_arguments['printer'] = printer
        globals()[target_command](**command_arguments)
--- a/src/escpos/codepages.py
+++ b/src/escpos/codepages.py
@@ -1,3 +1,11 @@
+#!/usr/bin/env python
+#  -*- coding: utf-8 -*-
+
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+from __future__ import unicode_literals
+
 from .capabilities import CAPABILITIES


--- a/src/escpos/config.py
+++ b/src/escpos/config.py
@@ -1,3 +1,4 @@
+#  -*- coding: utf-8 -*-
 """ ESC/POS configuration manager.

 This module contains the implentations of abstract base class :py:class:`Config`.
@@ -10,11 +11,13 @@ from __future__ import print_function
 from __future__ import unicode_literals

 import os
+
 import appdirs
+
 import yaml

-from . import printer
 from . import exceptions
+from . import printer


 class Config(object):
--- a/src/escpos/constants.py
+++ b/src/escpos/constants.py
@@ -225,6 +225,24 @@ BARCODE_TYPE_B = {
    'GS1 DATABAR EXPANDED':        _SET_BARCODE_TYPE(78),
 }

+BARCODE_FORMATS = {
+    'UPC-A':                       ([(11, 12)], "^[0-9]{11,12}$"),
+    'UPC-E':                       ([(7, 8), (11, 12)], "^([0-9]{7,8}|[0-9]{11,12})$"),
+    'EAN13':                       ([(12, 13)], "^[0-9]{12,13}$"),
+    'EAN8':                        ([(7, 8)], "^[0-9]{7,8}$"),
+    'CODE39':                      ([(1, 255)], "^([0-9A-Z \$\%\+\-\.\/]+|\*[0-9A-Z \$\%\+\-\.\/]+\*)$"),
+    'ITF':                         ([(2, 255)], "^([0-9]{2})+$"),
+    'NW7':                         ([(1, 255)], "^[A-Da-d][0-9\$\+\-\.\/\:]+[A-Da-d]$"),
+    'CODABAR':                     ([(1, 255)], "^[A-Da-d][0-9\$\+\-\.\/\:]+[A-Da-d]$"),  # Same as NW7
+    'CODE93':                      ([(1, 255)], "^[\\x00-\\x7F]+$"),
+    'CODE128':                     ([(2, 255)], "^\{[A-C][\\x00-\\x7F]+$"),
+    'GS1-128':                     ([(2, 255)], "^\{[A-C][\\x00-\\x7F]+$"), # same as CODE128
+    'GS1 DATABAR OMNIDIRECTIONAL': ([(13,13)], "^[0-9]{13}$"),
+    'GS1 DATABAR TRUNCATED':       ([(13,13)], "^[0-9]{13}$"), # same as GS1 omnidirectional
+    'GS1 DATABAR LIMITED':         ([(13,13)], "^[01][0-9]{12}$"),
+    'GS1 DATABAR EXPANDED':        ([(2,255)], "^\([0-9][A-Za-z0-9 \!\"\%\&\'\(\)\*\+\,\-\.\/\:\;\<\=\>\?\_\{]+$"),
+}
+
 BARCODE_TYPES = {
    'A': BARCODE_TYPE_A,
    'B': BARCODE_TYPE_B,
@@ -251,5 +269,10 @@ S_RASTER_2H = _PRINT_RASTER_IMG(b'\x02')  # Set raster image double height
 S_RASTER_Q  = _PRINT_RASTER_IMG(b'\x03')  # Set raster image quadruple

 # Status Command
-RT_STATUS_ONLINE = DLE + EOT +  b'\x01';
-RT_MASK_ONLINE = 8;
+RT_STATUS = DLE + EOT
+RT_STATUS_ONLINE = RT_STATUS +  b'\x01'
+RT_STATUS_PAPER = RT_STATUS +  b'\x04'
+RT_MASK_ONLINE = 8
+RT_MASK_PAPER = 18
+RT_MASK_LOWPAPER = 30
+RT_MASK_NOPAPER = 114
--- a/src/escpos/escpos.py
+++ b/src/escpos/escpos.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 #  -*- coding: utf-8 -*-
 """ Main class

@@ -15,38 +15,41 @@ from __future__ import division
 from __future__ import print_function
 from __future__ import unicode_literals

-import qrcode
+import os
 import textwrap
-import six
 import time
+from abc import ABCMeta, abstractmethod  # abstract base class support
+from re import match as re_match

 import barcode
 from barcode.writer import ImageWriter

-from .constants import ESC, GS, NUL, QR_ECLEVEL_L, QR_ECLEVEL_M, QR_ECLEVEL_H, QR_ECLEVEL_Q
-from .constants import QR_MODEL_1, QR_MODEL_2, QR_MICRO, BARCODE_TYPES, BARCODE_HEIGHT, BARCODE_WIDTH
-from .constants import BARCODE_FONT_A, BARCODE_FONT_B
+import qrcode
+
+import six
+
+from .capabilities import BARCODE_B, get_profile
+from .constants import BARCODE_FONT_A, BARCODE_FONT_B, BARCODE_FORMATS
 from .constants import BARCODE_TXT_OFF, BARCODE_TXT_BTH, BARCODE_TXT_ABV, BARCODE_TXT_BLW
-from .constants import TXT_SIZE, TXT_NORMAL
-from .constants import SET_FONT
+from .constants import BARCODE_TYPES, BARCODE_HEIGHT, BARCODE_WIDTH
+from .constants import CD_KICK_DEC_SEQUENCE, CD_KICK_5, CD_KICK_2, PAPER_FULL_CUT, PAPER_PART_CUT
+from .constants import CTL_VT, CTL_CR, CTL_FF, CTL_LF, CTL_SET_HT, PANEL_BUTTON_OFF, PANEL_BUTTON_ON
+from .constants import ESC, GS, NUL, QR_ECLEVEL_L, QR_ECLEVEL_M, QR_ECLEVEL_H, QR_ECLEVEL_Q
+from .constants import HW_INIT, HW_RESET, HW_SELECT
 from .constants import LINESPACING_FUNCS, LINESPACING_RESET
 from .constants import LINE_DISPLAY_OPEN, LINE_DISPLAY_CLEAR, LINE_DISPLAY_CLOSE
-from .constants import CD_KICK_DEC_SEQUENCE, CD_KICK_5, CD_KICK_2, PAPER_FULL_CUT, PAPER_PART_CUT
-from .constants import HW_RESET, HW_SELECT, HW_INIT
-from .constants import CTL_VT, CTL_CR, CTL_FF, CTL_LF, CTL_SET_HT, PANEL_BUTTON_OFF, PANEL_BUTTON_ON
+from .constants import QR_MODEL_1, QR_MODEL_2, QR_MICRO
+from .constants import RT_MASK_ONLINE, RT_STATUS_ONLINE
+from .constants import RT_STATUS_PAPER, RT_MASK_PAPER, RT_MASK_LOWPAPER, RT_MASK_NOPAPER
+from .constants import SET_FONT
+from .constants import TXT_SIZE, TXT_NORMAL
 from .constants import TXT_STYLE
-from .constants import RT_STATUS_ONLINE, RT_MASK_ONLINE
-
-from .exceptions import BarcodeTypeError, BarcodeSizeError, TabPosError
-from .exceptions import CashDrawerError, SetVariableError, BarcodeCodeError
-from .exceptions import ImageWidthError
-
+from .exceptions import BarcodeCodeError, BarcodeSizeError, BarcodeTypeError
+from .exceptions import CashDrawerError, ImageWidthError
+from .exceptions import SetVariableError, TabPosError
+from .image import EscposImage
 from .magicencode import MagicEncode

-from abc import ABCMeta, abstractmethod  # abstract base class support
-from escpos.image import EscposImage
-from escpos.capabilities import get_profile, BARCODE_B
-

@six.add_metaclass(ABCMeta)
 class Escpos(object):
@@ -79,14 +82,14 @@ class Escpos(object):
        """
        pass

-    def _read(self, msg):
+    def _read(self):
        """ Returns a NotImplementedError if the instance of the class doesn't override this method.
        :raises NotImplementedError
        """
        raise NotImplementedError()

-    def image(self, img_source, high_density_vertical=True, high_density_horizontal=True, impl="bitImageRaster",
-              fragment_height=960):
+    def image(self, img_source, high_density_vertical=True, high_density_horizontal=True, impl='bitImageRaster',
+              fragment_height=960, center=False):
        """ Print an image

        You can select whether the printer should print in high density or not. The default value is high density.
@@ -107,14 +110,19 @@ class Escpos(object):
        :param high_density_horizontal: print in high density in horizontal direction *default:* True
        :param impl: choose image printing mode between `bitImageRaster`, `graphics` or `bitImageColumn`
        :param fragment_height: Images larger than this will be split into multiple fragments *default:* 960
+        :param center: Center image horizontally *default:* False

        """
        im = EscposImage(img_source)

        try:
            max_width = int(self.profile.profile_data['media']['width']['pixels'])
+
            if im.width > max_width:
                raise ImageWidthError('{} > {}'.format(im.width, max_width))
+
+            if center:
+                im.center(max_width)
        except KeyError:
            # If the printer's pixel width is not known, print anyways...
            pass
@@ -132,14 +140,14 @@ class Escpos(object):
                           fragment_height=fragment_height)
            return

-        if impl == "bitImageRaster":
+        if impl == 'bitImageRaster':
            # GS v 0, raster format bit image
            density_byte = (0 if high_density_horizontal else 1) + (0 if high_density_vertical else 2)
-            header = GS + b"v0" + six.int2byte(density_byte) + self._int_low_high(im.width_bytes, 2) +\
+            header = GS + b'v0' + six.int2byte(density_byte) + self._int_low_high(im.width_bytes, 2) +\
                self._int_low_high(im.height, 2)
            self._raw(header + im.to_raster_format())

-        if impl == "graphics":
+        if impl == 'graphics':
            # GS ( L raster format graphics
            img_header = self._int_low_high(im.width, 2) + self._int_low_high(im.height, 2)
            tone = b'0'
@@ -151,14 +159,14 @@ class Escpos(object):
            self._image_send_graphics_data(b'0', b'p', header + raster_data)
            self._image_send_graphics_data(b'0', b'2', b'')

-        if impl == "bitImageColumn":
+        if impl == 'bitImageColumn':
            # ESC *, column format bit image
            density_byte = (1 if high_density_horizontal else 0) + (32 if high_density_vertical else 0)
-            header = ESC + b"*" + six.int2byte(density_byte) + self._int_low_high(im.width, 2)
-            outp = [ESC + b"3" + six.int2byte(16)]  # Adjust line-feed size
+            header = ESC + b'*' + six.int2byte(density_byte) + self._int_low_high(im.width, 2)
+            outp = [ESC + b'3' + six.int2byte(16)]  # Adjust line-feed size
            for blob in im.to_column_format(high_density_vertical):
-                outp.append(header + blob + b"\n")
-            outp.append(ESC + b"2")  # Reset line-feed size
+                outp.append(header + blob + b'\n')
+            outp.append(ESC + b'2')  # Reset line-feed size
            self._raw(b''.join(outp))

    def _image_send_graphics_data(self, m, fn, data):
@@ -172,7 +180,8 @@ class Escpos(object):
        header = self._int_low_high(len(data) + 2, 2)
        self._raw(GS + b'(L' + header + m + fn + data)

-    def qr(self, content, ec=QR_ECLEVEL_L, size=3, model=QR_MODEL_2, native=False):
+    def qr(self, content, ec=QR_ECLEVEL_L, size=3, model=QR_MODEL_2,
+           native=False, center=False, impl='bitImageRaster'):
        """ Print QR Code for the provided string

        :param content: The content of the code. Numeric data will be more efficiently compacted.
@@ -184,21 +193,22 @@ class Escpos(object):
            by all printers).
        :param native: True to render the code on the printer, False to render the code as an image and send it to the
            printer (Default)
+        :param center: Centers the code *default:* False
        """
        # Basic validation
        if ec not in [QR_ECLEVEL_L, QR_ECLEVEL_M, QR_ECLEVEL_H, QR_ECLEVEL_Q]:
-            raise ValueError("Invalid error correction level")
+            raise ValueError('Invalid error correction level')
        if not 1 <= size <= 16:
-            raise ValueError("Invalid block size (must be 1-16)")
+            raise ValueError('Invalid block size (must be 1-16)')
        if model not in [QR_MODEL_1, QR_MODEL_2, QR_MICRO]:
-            raise ValueError("Invalid QR model (must be one of QR_MODEL_1, QR_MODEL_2, QR_MICRO)")
-        if content == "":
+            raise ValueError('Invalid QR model (must be one of QR_MODEL_1, QR_MODEL_2, QR_MICRO)')
+        if content == '':
            # Handle edge case by printing nothing.
            return
        if not native:
            # Map ESC/POS error correction levels to python 'qrcode' library constant and render to an image
            if model != QR_MODEL_2:
-                raise ValueError("Invalid QR model for qrlib rendering (must be QR_MODEL_2)")
+                raise ValueError('Invalid QR model for qrlib rendering (must be QR_MODEL_2)')
            python_qr_ec = {
                QR_ECLEVEL_H: qrcode.constants.ERROR_CORRECT_H,
                QR_ECLEVEL_L: qrcode.constants.ERROR_CORRECT_L,
@@ -209,13 +219,18 @@ class Escpos(object):
            qr_code.add_data(content)
            qr_code.make(fit=True)
            qr_img = qr_code.make_image()
-            im = qr_img._img.convert("RGB")
+            im = qr_img._img.convert('RGB')
+
            # Convert the RGB image in printable image
            self.text('\n')
-            self.image(im)
+            self.image(im, center=center, impl=impl)
            self.text('\n')
            self.text('\n')
            return
+
+        if center:
+            raise NotImplementedError('Centering not implemented for native QR rendering')
+
        # Native 2D code printing
        cn = b'1'  # Code type for QR code
        # Select model: 1, 2 or micro.
@@ -237,7 +252,7 @@ class Escpos(object):
        :param m: Modifier/variant for function. Often '0' where used.
        """
        if len(m) > 1 or len(cn) != 1 or len(fn) != 1:
-            raise ValueError("cn and fn must be one byte each.")
+            raise ValueError('cn and fn must be one byte each.')
        header = self._int_low_high(len(data) + len(m) + 2, 2)
        self._raw(GS + b'(k' + header + cn + fn + m + data)

@@ -250,16 +265,16 @@ class Escpos(object):
        """
        max_input = (256 << (out_bytes * 8) - 1)
        if not 1 <= out_bytes <= 4:
-            raise ValueError("Can only output 1-4 byes")
+            raise ValueError('Can only output 1-4 bytes')
        if not 0 <= inp_number <= max_input:
-            raise ValueError("Number too large. Can only output up to {0} in {1} byes".format(max_input, out_bytes))
+            raise ValueError('Number too large. Can only output up to {0} in {1} bytes'.format(max_input, out_bytes))
        outp = b''
        for _ in range(0, out_bytes):
            outp += six.int2byte(inp_number % 256)
            inp_number //= 256
        return outp

-    def charcode(self, code="AUTO"):
+    def charcode(self, code='AUTO'):
        """ Set Character Code Table

        Sets the control sequence from ``CHARCODE`` in :py:mod:`escpos.constants` as active. It will be sent with
@@ -269,22 +284,47 @@ class Escpos(object):
        :param code: Name of CharCode
        :raises: :py:exc:`~escpos.exceptions.CharCodeError`
        """
-        if code.upper() == "AUTO":
+        if code.upper() == 'AUTO':
            self.magic.force_encoding(False)
        else:
            self.magic.force_encoding(code)

-    def barcode(self, code, bc, height=64, width=3, pos="BELOW", font="A",
-                align_ct=True, function_type=None):
+    @staticmethod
+    def check_barcode(bc, code):
+        """
+        This method checks if the barcode is in the proper format.
+        The validation concerns the barcode length and the set of characters, but won't compute/validate any checksum.
+        The full set of requirement for each barcode type is available in the ESC/POS documentation.
+
+        As an example, using EAN13, the barcode `12345678901` will be correct, because it can be rendered by the
+        printer. But it does not suit the EAN13 standard, because the checksum digit is missing. Adding a wrong
+        checksum in the end will also be considered correct, but adding a letter won't (EAN13 is numeric only).
+
+        .. todo:: Add a method to compute the checksum for the different standards
+
+        .. todo:: For fixed-length standards with mandatory checksum (EAN, UPC),
+            compute and add the checksum automatically if missing.
+
+        :param bc: barcode format, see :py:func`~escpos.Escpos.barcode`
+        :param code: alphanumeric data to be printed as bar code, see :py:func`~escpos.Escpos.barcode`
+        :return: bool
+        """
+        if bc not in BARCODE_FORMATS:
+            return False
+
+        bounds, regex = BARCODE_FORMATS[bc]
+        return any(bound[0] <= len(code) <= bound[1] for bound in bounds) and re_match(regex, code)
+
+    def barcode(self, code, bc, height=64, width=3, pos='BELOW', font='A',
+                align_ct=True, function_type=None, check=True):
        """ Print Barcode

        This method allows to print barcodes. The rendering of the barcode is done by the printer and therefore has to
-        be supported by the unit. Currently you have to check manually whether your barcode text is correct. Uncorrect
-        barcodes may lead to unexpected printer behaviour. There are two forms of the barcode function. Type A is
-        default but has fewer barcodes, while type B has some more to choose from.
-
-        .. todo:: Add a method to check barcode codes. Alternatively or as an addition write explanations about each
-                  barcode-type. Research whether the check digits can be computed autmatically.
+        be supported by the unit. By default, this method will check whether your barcode text is correct, that is
+        the characters and lengths are supported by ESCPOS. Call the method with `check=False` to disable the check, but
+        note that uncorrect barcodes may lead to unexpected printer behaviour.
+        There are two forms of the barcode function. Type A is default but has fewer barcodes,
+        while type B has some more to choose from.

        Use the parameters `height` and `width` for adjusting of the barcode size. Please take notice that the barcode
        will not be printed if it is outside of the printable area. (Which should be impossible with this method, so
@@ -352,6 +392,10 @@ class Escpos(object):
            function based on the current profile.
            *default*: A

+        :param check: If this parameter is True, the barcode format will be checked to ensure it meets the bc
+            requirements as defigned in the esc/pos documentation. See py:func:`~escpos.Escpos.check_barcode`
+            for more information. *default*: True.
+
        :raises: :py:exc:`~escpos.exceptions.BarcodeSizeError`,
                 :py:exc:`~escpos.exceptions.BarcodeTypeError`,
                 :py:exc:`~escpos.exceptions.BarcodeCodeError`
@@ -364,21 +408,28 @@ class Escpos(object):
                if bc in BARCODE_TYPES['B']:
                    if not self.profile.supports(BARCODE_B):
                        raise BarcodeTypeError((
-                            "Barcode type '{bc} not supported for "
-                            "the current printer profile").format(bc=bc))
+                            "Barcode type '{bc}' not supported for "
+                            'the current printer profile').format(bc=bc))
                    function_type = 'B'
                else:
                    raise BarcodeTypeError((
-                        "Barcode type '{bc} is not valid").format(bc=bc))
+                        "Barcode type '{bc}' is not valid").format(bc=bc))

        bc_types = BARCODE_TYPES[function_type.upper()]
        if bc.upper() not in bc_types.keys():
            raise BarcodeTypeError((
-                "Barcode type '{bc}' not valid for barcode function type "
-                "{function_type}").format(
+                "Barcode '{bc}' not valid for barcode function type "
+                '{function_type}').format(
                    bc=bc,
-                    function_type=function_type,
-                ))
+                    function_type=function_type,)
+            )
+
+        if check and not self.check_barcode(bc, code):
+            raise BarcodeCodeError((
+                "Barcode '{code}' not in a valid format for type '{bc}'").format(
+                code=code,
+                bc=bc,
+            ))

        # Align Bar Code()
        if align_ct:
@@ -387,30 +438,30 @@ class Escpos(object):
        if 1 <= height <= 255:
            self._raw(BARCODE_HEIGHT + six.int2byte(height))
        else:
-            raise BarcodeSizeError("height = {height}".format(height=height))
+            raise BarcodeSizeError('height = {height}'.format(height=height))
        # Width
        if 2 <= width <= 6:
            self._raw(BARCODE_WIDTH + six.int2byte(width))
        else:
-            raise BarcodeSizeError("width = {width}".format(width=width))
+            raise BarcodeSizeError('width = {width}'.format(width=width))
        # Font
-        if font.upper() == "B":
+        if font.upper() == 'B':
            self._raw(BARCODE_FONT_B)
        else:  # DEFAULT FONT: A
            self._raw(BARCODE_FONT_A)
        # Position
-        if pos.upper() == "OFF":
+        if pos.upper() == 'OFF':
            self._raw(BARCODE_TXT_OFF)
-        elif pos.upper() == "BOTH":
+        elif pos.upper() == 'BOTH':
            self._raw(BARCODE_TXT_BTH)
-        elif pos.upper() == "ABOVE":
+        elif pos.upper() == 'ABOVE':
            self._raw(BARCODE_TXT_ABV)
        else:  # DEFAULT POSITION: BELOW
            self._raw(BARCODE_TXT_BLW)

        self._raw(bc_types[bc.upper()])

-        if function_type.upper() == "B":
+        if function_type.upper() == 'B':
            self._raw(six.int2byte(len(code)))

        # Print Code
@@ -419,7 +470,7 @@ class Escpos(object):
        else:
            raise BarcodeCodeError()

-        if function_type.upper() == "A":
+        if function_type.upper() == 'A':
            self._raw(NUL)

    def soft_barcode(self, barcode_type, data, impl='bitImageColumn',
@@ -437,11 +488,12 @@ class Escpos(object):
        barcode_class = barcode.get_barcode_class(barcode_type)
        my_code = barcode_class(data, writer=image_writer)

-        my_code.write("/dev/null", {
-            'module_height': module_height,
-            'module_width': module_width,
-            'text_distance': text_distance
-        })
+        with open(os.devnull, 'wb') as nullfile:
+            my_code.write(nullfile, {
+                'module_height': module_height,
+                'module_width': module_width,
+                'text_distance': text_distance
+            })

        # Retrieve the Pillow image and print it
        image = my_code.writer._image
@@ -459,6 +511,28 @@ class Escpos(object):
        txt = six.text_type(txt)
        self.magic.write(txt)

+    def textln(self, txt=''):
+        """Print alpha-numeric text with a newline
+
+        The text has to be encoded in the currently selected codepage.
+        The input text has to be encoded in unicode.
+
+        :param txt: text to be printed with a newline
+        :raises: :py:exc:`~escpos.exceptions.TextError`
+        """
+        self.text('{}\n'.format(txt))
+
+    def ln(self, count=1):
+        """Print a newline or more
+
+        :param count: number of newlines to print
+        :raises: :py:exc:`ValueError` if count < 0
+        """
+        if count < 0:
+            raise ValueError('Count cannot be lesser than 0')
+        if count > 0:
+            self.text('\n' * count)
+
    def block_text(self, txt, font=None, columns=None):
        """ Text is printed wrapped to specified columns

@@ -516,8 +590,7 @@ class Escpos(object):
        """

        if custom_size:
-            if 1 <= width <= 8 and 1 <= height <= 8 and isinstance(width, int) and\
-              isinstance(height, int):
+            if 1 <= width <= 8 and 1 <= height <= 8 and isinstance(width, int) and isinstance(height, int):
                size_byte = TXT_STYLE['width'][width] + TXT_STYLE['height'][height]
                self._raw(TXT_SIZE + six.int2byte(size_byte))
            else:
@@ -565,12 +638,11 @@ class Escpos(object):
            return

        if divisor not in LINESPACING_FUNCS:
-            raise ValueError("divisor must be either 360, 180 or 60")
-        if (divisor in [360, 180]
-                and (not(0 <= spacing <= 255))):
-            raise ValueError("spacing must be a int between 0 and 255 when divisor is 360 or 180")
+            raise ValueError('divisor must be either 360, 180 or 60')
+        if (divisor in [360, 180] and (not(0 <= spacing <= 255))):
+            raise ValueError('spacing must be a int between 0 and 255 when divisor is 360 or 180')
        if divisor == 60 and (not(0 <= spacing <= 85)):
-            raise ValueError("spacing must be a int between 0 and 85 when divisor is 60")
+            raise ValueError('spacing must be a int between 0 and 85 when divisor is 60')

        self._raw(LINESPACING_FUNCS[divisor] + six.int2byte(spacing))

@@ -598,12 +670,12 @@ class Escpos(object):
        if mode not in ('FULL', 'PART'):
            raise ValueError("Mode must be one of ('FULL', 'PART')")

-        if mode == "PART":
+        if mode == 'PART':
            if self.profile.supports('paperPartCut'):
                self._raw(PAPER_PART_CUT)
            elif self.profile.supports('paperFullCut'):
                self._raw(PAPER_FULL_CUT)
-        elif mode == "FULL":
+        elif mode == 'FULL':
            if self.profile.supports('paperFullCut'):
                self._raw(PAPER_FULL_CUT)
            elif self.profile.supports('paperPartCut'):
@@ -625,8 +697,8 @@ class Escpos(object):
        else:
            try:
                self._raw(CD_KICK_DEC_SEQUENCE(*pin))
-            except:
-                raise CashDrawerError()
+            except TypeError as err:
+                raise CashDrawerError(err)

    def linedisplay_select(self, select_display=False):
        """ Selects the line display or the printer
@@ -656,6 +728,7 @@ class Escpos(object):

        You should connect a line display to your printer. You can do this by daisy-chaining
        the display between your computer and printer.
+
        :param text: Text to display
        """
        self.linedisplay_select(select_display=True)
@@ -672,11 +745,11 @@ class Escpos(object):
            * SELECT
            * RESET
        """
-        if hw.upper() == "INIT":
+        if hw.upper() == 'INIT':
            self._raw(HW_INIT)
-        elif hw.upper() == "SELECT":
+        elif hw.upper() == 'SELECT':
            self._raw(HW_SELECT)
-        elif hw.upper() == "RESET":
+        elif hw.upper() == 'RESET':
            self._raw(HW_RESET)
        else:  # DEFAULT: DOES NOTHING
            pass
@@ -691,9 +764,9 @@ class Escpos(object):
        """
        if 0 <= n <= 255:
            # ESC d n
-            self._raw(ESC + b"d" + six.int2byte(n))
+            self._raw(ESC + b'd' + six.int2byte(n))
        else:
-            raise ValueError("n must be betwen 0 and 255")
+            raise ValueError('n must be betwen 0 and 255')

    def control(self, ctl, count=5, tab_size=8):
        """ Feed control sequences
@@ -711,13 +784,13 @@ class Escpos(object):
        :raises: :py:exc:`~escpos.exceptions.TabPosError`
        """
        # Set position
-        if ctl.upper() == "LF":
+        if ctl.upper() == 'LF':
            self._raw(CTL_LF)
-        elif ctl.upper() == "FF":
+        elif ctl.upper() == 'FF':
            self._raw(CTL_FF)
-        elif ctl.upper() == "CR":
+        elif ctl.upper() == 'CR':
            self._raw(CTL_CR)
-        elif ctl.upper() == "HT":
+        elif ctl.upper() == 'HT':
            if not (0 <= count <= 32 and
                    1 <= tab_size <= 255 and
                    count * tab_size < 256):
@@ -728,7 +801,7 @@ class Escpos(object):
                for iterator in range(1, count):
                    self._raw(six.int2byte(iterator * tab_size))
                self._raw(NUL)
-        elif ctl.upper() == "VT":
+        elif ctl.upper() == 'VT':
            self._raw(CTL_VT)

    def panel_buttons(self, enable=True):
@@ -754,26 +827,58 @@ class Escpos(object):
        else:
            self._raw(PANEL_BUTTON_OFF)

-    def query_status(self):
-        """ Queries the printer for its status, and returns an array of integers containing it.
-        :rtype: array(integer)"""
-        self._raw(RT_STATUS_ONLINE)
+    def query_status(self, mode):
+        """
+        Queries the printer for its status, and returns an array of integers containing it.
+
+        :param mode: Integer that sets the status mode queried to the printer.
+            - RT_STATUS_ONLINE: Printer status.
+            - RT_STATUS_PAPER: Paper sensor.
+        :rtype: array(integer)
+        """
+        self._raw(mode)
        time.sleep(1)
        status = self._read()
-        return status or [RT_MASK_ONLINE]
+        return status

    def is_online(self):
-        """ Queries the printer its online status.
-        When online, returns True; False otherwise.
-        :rtype: bool: True if online, False if offline."""
-        return not (self.query_status()[0] & RT_MASK_ONLINE)
+        """
+        Queries the online status of the printer.
+
+        :returns: When online, returns ``True``; ``False`` otherwise.
+        :rtype: bool
+        """
+        status = self.query_status(RT_STATUS_ONLINE)
+        if len(status) == 0:
+            return False
+        return not (status[0] & RT_MASK_ONLINE)
+
+    def paper_status(self):
+        """
+        Queries the paper status of the printer.
+
+        Returns 2 if there is plenty of paper, 1 if the paper has arrived to
+        the near-end sensor and 0 if there is no paper.
+
+        :returns: 2: Paper is adequate. 1: Paper ending. 0: No paper.
+        :rtype: int
+        """
+        status = self.query_status(RT_STATUS_PAPER)
+        if len(status) == 0:
+            return 2
+        if (status[0] & RT_MASK_NOPAPER == RT_MASK_NOPAPER):
+            return 0
+        if (status[0] & RT_MASK_LOWPAPER == RT_MASK_LOWPAPER):
+            return 1
+        if (status[0] & RT_MASK_PAPER == RT_MASK_PAPER):
+            return 2


 class EscposIO(object):
    """ESC/POS Printer IO object

    Allows the class to be used together with the `with`-statement. You have to define a printer instance
-    and assign it to the EsposIO-class.
+    and assign it to the EscposIO class.
    This example explains the usage:

    .. code-block:: Python
@@ -822,16 +927,16 @@ class EscposIO(object):
        elif isinstance(text, list) or isinstance(text, tuple):
            lines = text
        else:
-            lines = ["{0}".format(text), ]
+            lines = ['{0}'.format(text), ]

        # TODO check unicode handling
        # TODO flush? or on print? (this should prob rather be handled by the _raw-method)
        for line in lines:
            self.printer.set(**params)
            if isinstance(text, six.text_type):
-                self.printer.text(u"{0}\n".format(line))
+                self.printer.text(u'{0}\n'.format(line))
            else:
-                self.printer.text("{0}\n".format(line))
+                self.printer.text('{0}\n'.format(line))

    def close(self):
        """ called upon closing the `with`-statement
--- a/src/escpos/exceptions.py
+++ b/src/escpos/exceptions.py
@@ -51,13 +51,13 @@ class BarcodeTypeError(Error):
    one of those specified in :py:meth:`escpos.escpos.Escpos.barcode`.
    The returned error code is `10`.
    """
-    def __init__(self, msg=""):
+    def __init__(self, msg=''):
        Error.__init__(self, msg)
        self.msg = msg
        self.resultcode = 10

    def __str__(self):
-        return "No Barcode type is defined ({msg})".format(msg=self.msg)
+        return 'No Barcode type is defined ({msg})'.format(msg=self.msg)


 class BarcodeSizeError(Error):
@@ -67,28 +67,29 @@ class BarcodeSizeError(Error):
    The size of the barcode has to be in the range that is specified in :py:meth:`escpos.escpos.Escpos.barcode`.
    The resulting returncode is `20`.
    """
-    def __init__(self, msg=""):
+    def __init__(self, msg=''):
        Error.__init__(self, msg)
        self.msg = msg
        self.resultcode = 20

    def __str__(self):
-        return "Barcode size is out of range ({msg})".format(msg=self.msg)
+        return 'Barcode size is out of range ({msg})'.format(msg=self.msg)


 class BarcodeCodeError(Error):
-    """ No Barcode code was supplied.
+    """ No Barcode code was supplied, or it is incorrect.

-    No data for the barcode has been supplied in :py:meth:`escpos.escpos.Escpos.barcode`.
+    No data for the barcode has been supplied in :py:meth:`escpos.escpos.Escpos.barcode` or the the `check` parameter
+    was True and the check failed.
    The returncode for this exception is `30`.
    """
-    def __init__(self, msg=""):
+    def __init__(self, msg=''):
        Error.__init__(self, msg)
        self.msg = msg
        self.resultcode = 30

    def __str__(self):
-        return "No Barcode code was supplied ({msg})".format(msg=self.msg)
+        return 'No Barcode code was supplied ({msg})'.format(msg=self.msg)


 class ImageSizeError(Error):
@@ -96,7 +97,7 @@ class ImageSizeError(Error):

    The returncode for this exception is `40`.
    """
-    def __init__(self, msg=""):
+    def __init__(self, msg=''):
        Error.__init__(self, msg)
        self.msg = msg
        self.resultcode = 40
@@ -110,13 +111,13 @@ class ImageWidthError(Error):

    The return code for this exception is `41`.
    """
-    def __init__(self, msg=""):
+    def __init__(self, msg=''):
        Error.__init__(self, msg)
        self.msg = msg
        self.resultcode = 41

    def __str__(self):
-        return "Image width is too large ({msg})".format(msg=self.msg)
+        return 'Image width is too large ({msg})'.format(msg=self.msg)


 class TextError(Error):
@@ -125,13 +126,13 @@ class TextError(Error):
    This exception is raised when an empty string is passed to :py:meth:`escpos.escpos.Escpos.text`.
    The returncode for this exception is `50`.
    """
-    def __init__(self, msg=""):
+    def __init__(self, msg=''):
        Error.__init__(self, msg)
        self.msg = msg
        self.resultcode = 50

    def __str__(self):
-        return "Text string must be supplied to the text() method ({msg})".format(msg=self.msg)
+        return 'Text string must be supplied to the text() method ({msg})'.format(msg=self.msg)


 class CashDrawerError(Error):
@@ -140,13 +141,13 @@ class CashDrawerError(Error):
    A valid pin number has to be passed onto the method :py:meth:`escpos.escpos.Escpos.cashdraw`.
    The returncode for this exception is `60`.
    """
-    def __init__(self, msg=""):
+    def __init__(self, msg=''):
        Error.__init__(self, msg)
        self.msg = msg
        self.resultcode = 60

    def __str__(self):
-        return "Valid pin must be set to send pulse ({msg})".format(msg=self.msg)
+        return 'Valid pin must be set to send pulse ({msg})'.format(msg=self.msg)


 class TabPosError(Error):
@@ -156,13 +157,13 @@ class TabPosError(Error):
    This exception is raised by :py:meth:`escpos.escpos.Escpos.control`.
    The returncode for this exception is `70`.
    """
-    def __init__(self, msg=""):
+    def __init__(self, msg=''):
        Error.__init__(self, msg)
        self.msg = msg
        self.resultcode = 70

    def __str__(self):
-        return "Valid tab positions must be in the range 0 to 16 ({msg})".format(msg=self.msg)
+        return 'Valid tab positions must be in the range 0 to 16 ({msg})'.format(msg=self.msg)


 class CharCodeError(Error):
@@ -171,13 +172,13 @@ class CharCodeError(Error):
    The supplied charcode-name in :py:meth:`escpos.escpos.Escpos.charcode` is unknown.
    Ths returncode for this exception is `80`.
    """
-    def __init__(self, msg=""):
+    def __init__(self, msg=''):
        Error.__init__(self, msg)
        self.msg = msg
        self.resultcode = 80

    def __str__(self):
-        return "Valid char code must be set ({msg})".format(msg=self.msg)
+        return 'Valid char code must be set ({msg})'.format(msg=self.msg)


 class USBNotFoundError(Error):
@@ -186,13 +187,13 @@ class USBNotFoundError(Error):
    The USB device seems to be not plugged in.
    Ths returncode for this exception is `90`.
    """
-    def __init__(self, msg=""):
+    def __init__(self, msg=''):
        Error.__init__(self, msg)
        self.msg = msg
        self.resultcode = 90

    def __str__(self):
-        return "USB device not found ({msg})".format(msg=self.msg)
+        return 'USB device not found ({msg})'.format(msg=self.msg)


 class SetVariableError(Error):
@@ -201,13 +202,13 @@ class SetVariableError(Error):
    Check set variables against minimum and maximum values
    Ths returncode for this exception is `100`.
    """
-    def __init__(self, msg=""):
+    def __init__(self, msg=''):
        Error.__init__(self, msg)
        self.msg = msg
        self.resultcode = 100

    def __str__(self):
-        return "Set variable out of range ({msg})".format(msg=self.msg)
+        return 'Set variable out of range ({msg})'.format(msg=self.msg)


 # Configuration errors
@@ -218,13 +219,13 @@ class ConfigNotFoundError(Error):
    The default or passed configuration file could not be read
    Ths returncode for this exception is `200`.
    """
-    def __init__(self, msg=""):
+    def __init__(self, msg=''):
        Error.__init__(self, msg)
        self.msg = msg
        self.resultcode = 200

    def __str__(self):
-        return "Configuration not found ({msg})".format(msg=self.msg)
+        return 'Configuration not found ({msg})'.format(msg=self.msg)


 class ConfigSyntaxError(Error):
@@ -233,13 +234,13 @@ class ConfigSyntaxError(Error):
    The syntax is incorrect
    Ths returncode for this exception is `210`.
    """
-    def __init__(self, msg=""):
+    def __init__(self, msg=''):
        Error.__init__(self, msg)
        self.msg = msg
        self.resultcode = 210

    def __str__(self):
-        return "Configuration syntax is invalid ({msg})".format(msg=self.msg)
+        return 'Configuration syntax is invalid ({msg})'.format(msg=self.msg)


 class ConfigSectionMissingError(Error):
@@ -248,10 +249,10 @@ class ConfigSectionMissingError(Error):
    The part of the config asked for doesn't exist in the loaded configuration
    Ths returncode for this exception is `220`.
    """
-    def __init__(self, msg=""):
+    def __init__(self, msg=''):
        Error.__init__(self, msg)
        self.msg = msg
        self.resultcode = 220

    def __str__(self):
-        return "Configuration section is missing ({msg})".format(msg=self.msg)
+        return 'Configuration section is missing ({msg})'.format(msg=self.msg)
--- a/src/escpos/image.py
+++ b/src/escpos/image.py
@@ -1,3 +1,4 @@
+#  -*- coding: utf-8 -*-
 """ Image format handling class

 This module contains the image format handler :py:class:`EscposImage`.
@@ -14,6 +15,7 @@ from __future__ import print_function
 from __future__ import unicode_literals

 import math
+
 from PIL import Image, ImageOps


@@ -42,14 +44,14 @@ class EscposImage(object):
        # Convert to white RGB background, paste over white background
        # to strip alpha.
        img_original = img_original.convert('RGBA')
-        im = Image.new("RGB", img_original.size, (255, 255, 255))
+        im = Image.new('RGB', img_original.size, (255, 255, 255))
        im.paste(img_original, mask=img_original.split()[3])
        # Convert down to greyscale
-        im = im.convert("L")
+        im = im.convert('L')
        # Invert: Only works on 'L' images
        im = ImageOps.invert(im)
        # Pure black and white
-        self._im = im.convert("1")
+        self._im = im.convert('1')

    @property
    def width(self):
@@ -105,7 +107,7 @@ class EscposImage(object):
        :param fragment_height: height of fragment
        :return: list of PIL objects
        """
-        passes = int(math.ceil(self.height/fragment_height))
+        passes = int(math.ceil(self.height // fragment_height))
        fragments = []
        for n in range(0, passes):
            left = 0
@@ -115,3 +117,19 @@ class EscposImage(object):
            box = (left, upper, right, lower)
            fragments.append(self.img_original.crop(box))
        return fragments
+
+    def center(self, max_width):
+        """In-place image centering
+
+        :param: Maximum width in order to deduce x offset for centering
+        :return: None
+        """
+        old_width, height = self._im.size
+        new_size = (max_width, height)
+
+        new_im = Image.new('1', new_size)
+        paste_x = int((max_width - old_width) / 2)
+
+        new_im.paste(self._im, (paste_x, 0))
+
+        self._im = new_im
--- a/src/escpos/katakana.py
+++ b/src/escpos/katakana.py
@@ -33,7 +33,7 @@ def encode_katakana(text):
            # TODO doesn't this discard all that is not in the map? Can we be sure that the input does contain only
            # encodable characters? We could at least throw an exception if encoding is not possible.
            pass
-    return b"".join(encoded)
+    return b''.join(encoded)


 TXT_ENC_KATAKANA_MAP = {
--- a/src/escpos/magicencode.py
+++ b/src/escpos/magicencode.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 #  -*- coding: utf-8 -*-
 """ Magic Encode

@@ -18,10 +18,12 @@ from __future__ import print_function
 from __future__ import unicode_literals

 from builtins import bytes
+
+import six
+
+from .codepages import CodePages
 from .constants import CODEPAGE_CHANGE
 from .exceptions import Error
-from .codepages import CodePages
-import six


 class Encoder(object):
@@ -62,7 +64,7 @@ class Encoder(object):
            raise ValueError((
                'Encoding "{}" cannot be used for the current profile. '
                'Valid encodings are: {}'
-                ).format(encoding, ','.join(self.codepages.keys())))
+            ).format(encoding, ','.join(self.codepages.keys())))
        return encoding

    @staticmethod
@@ -75,11 +77,11 @@ class Encoder(object):
        """
        codepage = CodePages.get_encoding(encoding)
        if 'data' in codepage:
-            encodable_chars = list("".join(codepage['data']))
+            encodable_chars = list(''.join(codepage['data']))
            assert(len(encodable_chars) == 128)
            return encodable_chars
        elif 'python_encode' in codepage:
-            encodable_chars = [u" "] * 128
+            encodable_chars = [u' '] * 128
            for i in range(0, 128):
                codepoint = i + 128
                try:
@@ -280,7 +282,7 @@ class MagicEncode(object):

    def write_with_encoding(self, encoding, text):
        if text is not None and type(text) is not six.text_type:
-            raise Error("The supplied text has to be unicode, but is of type {type}.".format(
+            raise Error('The supplied text has to be unicode, but is of type {type}.'.format(
                type=type(text)
            ))

--- a/src/escpos/printer.py
+++ b/src/escpos/printer.py
@@ -13,10 +13,12 @@ from __future__ import division
 from __future__ import print_function
 from __future__ import unicode_literals

+import socket
+
+import serial
+
 import usb.core
 import usb.util
-import serial
-import socket

 from .escpos import Escpos
 from .exceptions import USBNotFoundError
@@ -54,7 +56,7 @@ class Usb(Escpos):
        """ Search device on USB tree and set it as escpos device """
        self.device = usb.core.find(idVendor=self.idVendor, idProduct=self.idProduct)
        if self.device is None:
-            raise USBNotFoundError("Device not found or cable not plugged in.")
+            raise USBNotFoundError('Device not found or cable not plugged in.')

        check_driver = None

@@ -68,13 +70,13 @@ class Usb(Escpos):
                self.device.detach_kernel_driver(0)
            except usb.core.USBError as e:
                if check_driver is not None:
-                    print("Could not detatch kernel driver: {0}".format(str(e)))
+                    print('Could not detatch kernel driver: {0}'.format(str(e)))

        try:
            self.device.set_configuration()
            self.device.reset()
        except usb.core.USBError as e:
-            print("Could not set configuration: {0}".format(str(e)))
+            print('Could not set configuration: {0}'.format(str(e)))

    def _raw(self, msg):
        """ Print any command sent in raw format
@@ -107,7 +109,7 @@ class Serial(Escpos):

    """

-    def __init__(self, devfile="/dev/ttyS0", baudrate=9600, bytesize=8, timeout=1,
+    def __init__(self, devfile='/dev/ttyS0', baudrate=9600, bytesize=8, timeout=1,
                 parity=serial.PARITY_NONE, stopbits=serial.STOPBITS_ONE,
                 xonxoff=False, dsrdtr=True, *args, **kwargs):
        """
@@ -143,9 +145,9 @@ class Serial(Escpos):
                                    xonxoff=self.xonxoff, dsrdtr=self.dsrdtr)

        if self.device is not None:
-            print("Serial printer enabled")
+            print('Serial printer enabled')
        else:
-            print("Unable to open serial printer on: {0}".format(str(self.devfile)))
+            print('Unable to open serial printer on: {0}'.format(str(self.devfile)))

    def _raw(self, msg):
        """ Print any command sent in raw format
@@ -155,6 +157,10 @@ class Serial(Escpos):
        """
        self.device.write(msg)

+    def _read(self):
+        """ Reads a data buffer and returns it to the caller. """
+        return self.device.read(16)
+
    def close(self):
        """ Close Serial interface """
        if self.device is not None and self.device.is_open:
@@ -205,7 +211,7 @@ class Network(Escpos):
        self.device.connect((self.host, self.port))

        if self.device is None:
-            print("Could not open socket for {0}".format(self.host))
+            print('Could not open socket for {0}'.format(self.host))

    def _raw(self, msg):
        """ Print any command sent in raw format
@@ -236,10 +242,10 @@ class File(Escpos):

    """

-    def __init__(self, devfile="/dev/usb/lp0", auto_flush=True, *args, **kwargs):
+    def __init__(self, devfile='/dev/usb/lp0', auto_flush=True, *args, **kwargs):
        """

-        :param devfile : Device file under dev filesystem
+        :param devfile: Device file under dev filesystem
        :param auto_flush: automatically call flush after every call of _raw()
        """
        Escpos.__init__(self, *args, **kwargs)
@@ -249,10 +255,10 @@ class File(Escpos):

    def open(self):
        """ Open system file """
-        self.device = open(self.devfile, "wb")
+        self.device = open(self.devfile, 'wb')

        if self.device is None:
-            print("Could not open the specified file {0}".format(self.devfile))
+            print('Could not open the specified file {0}'.format(self.devfile))

    def flush(self):
        """ Flush printing content """
@@ -308,5 +314,13 @@ class Dummy(Escpos):
        """ Get the data that was sent to this printer """
        return b''.join(self._output_list)

+    def clear(self):
+        """ Clear the buffer of the printer
+
+        This method can be called if you send the contents to a physical printer
+        and want to use the Dummy printer for new output.
+        """
+        del self._output_list[:]
+
    def close(self):
        pass
--- a/test/test_function_barcode.py
+++ b/test/test_function_barcode.py
@@ -7,7 +7,7 @@ from __future__ import unicode_literals
 import escpos.printer as printer
 from escpos.constants import BARCODE_TYPE_A, BARCODE_TYPE_B
 from escpos.capabilities import Profile, BARCODE_B
-from escpos.exceptions import BarcodeTypeError
+from escpos.exceptions import BarcodeTypeError, BarcodeCodeError
 import pytest


@@ -36,3 +36,17 @@ def test_lacks_support(bctype, supports_b):
        instance.barcode('test', bctype)

    assert instance.output == b''
+
+
+@pytest.mark.parametrize("bctype,data", [
+    ('EAN13', 'AA'),
+    ('CODE128', '{D2354AA'),
+])
+def test_code_check(bctype, data):
+    """should raise an error if the barcode code is invalid.
+    """
+    instance = printer.Dummy()
+    with pytest.raises(BarcodeCodeError):
+        instance.barcode(data, bctype)
+
+    assert instance.output == b''
--- a/test/test_function_cashdraw.py
+++ b/test/test_function_cashdraw.py
@@ -0,0 +1,19 @@
+#!/usr/bin/python
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+from __future__ import unicode_literals
+
+import escpos.printer as printer
+from escpos.exceptions import CashDrawerError
+import pytest
+
+
+def test_raise_CashDrawerError():
+    """should raise an error if the sequence is invalid.
+    """
+    instance = printer.Dummy()
+    with pytest.raises(CashDrawerError):
+        # call with sequence that is too long
+        instance.cashdraw([1,1,1,1,1,1])
+
--- a/test/test_function_check_barcode.py
+++ b/test/test_function_check_barcode.py
@@ -0,0 +1,104 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+from __future__ import unicode_literals
+
+import escpos.printer as printer
+import pytest
+
+
+@pytest.mark.parametrize("bctype,data", [
+    ('UPC-A', '01234567890'),
+    ('UPC-A', '012345678905'),
+    ('UPC-E', '01234567'),
+    ('UPC-E', '0123456'),
+    ('UPC-E', '012345678905'),
+    ('EAN13', '0123456789012'),
+    ('EAN13', '012345678901'),
+    ('EAN8', '01234567'),
+    ('EAN8', '0123456'),
+    ('CODE39', 'ABC-1234'),
+    ('CODE39', 'ABC-1234-$$-+A'),
+    ('CODE39', '*WIKIPEDIA*'),
+    ('ITF', '010203040506070809'),
+    ('ITF', '11221133113344556677889900'),
+    ('CODABAR', 'A2030405060B'),
+    ('CODABAR', 'C11221133113344556677889900D'),
+    ('CODABAR', 'D0D'),
+    ('NW7', 'A2030405060B'),
+    ('NW7', 'C11221133113344556677889900D'),
+    ('NW7', 'D0D'),
+    ('CODE93', 'A2030405060B'),
+    ('CODE93', '+:$&23-7@$'),
+    ('CODE93', 'D0D'),
+    ('CODE128', '{A2030405060B'),
+    ('CODE128', '{C+:$&23-7@$'),
+    ('CODE128', '{B0D'),
+    ('GS1-128', '{A2030405060B'),
+    ('GS1-128', '{C+:$&23-7@$'),
+    ('GS1-128', '{B0D'),
+    ('GS1 DATABAR OMNIDIRECTIONAL', '0123456789123'),
+    ('GS1 DATABAR TRUNCATED', '0123456789123'),
+    ('GS1 DATABAR LIMITED', '0123456789123'),
+    ('GS1 DATABAR EXPANDED', '(9A{A20304+-%&06a0B'),
+    ('GS1 DATABAR EXPANDED', '(1 {C+:&23-7%'),
+    ('GS1 DATABAR EXPANDED', '(00000001234567678'),
+])
+def test_check_valid_barcode(bctype, data):
+    assert (printer.Escpos.check_barcode(bctype, data))
+
+
+@pytest.mark.parametrize("bctype,data", [
+    ('UPC-A', '01234567890123'),  # too long
+    ('UPC-A', '0123456789'),  # too short
+    ('UPC-A', '72527273-711'),  # invalid '-'
+    ('UPC-A', 'A12345678901'),  # invalid 'A'
+    ('UPC-E', '01234567890123'),  # too long
+    ('UPC-E', '012345'),  # too short
+    ('UPC-E', '72527-2'),  # invalid '-'
+    ('UPC-E', 'A123456'),  # invalid 'A'
+    ('EAN13', '0123456789'),  # too short
+    ('EAN13', 'A123456789012'),  # invalid 'A'
+    ('EAN13', '012345678901234'),  # too long
+    ('EAN8', '012345'),  # too short
+    ('EAN8', 'A123456789012'),  # invalid 'A'
+    ('EAN8', '012345678901234'),  # too long
+    ('CODE39', 'ALKJ_34'),  # invalid '_'
+    ('CODE39', 'A' * 256),  # too long
+    ('ITF', '010203040'),  # odd length
+    ('ITF', '0' * 256),  # too long
+    ('ITF', 'AB01'),  # invalid 'A'
+    ('CODABAR', '010203040'),  # no start/stop
+    ('CODABAR', '0' * 256),  # too long
+    ('CODABAR', 'AB-01F'),  # invalid 'B'
+    ('NW7', '010203040'),  # no start/stop
+    ('NW7', '0' * 256),  # too long
+    ('NW7', 'AB-01F'),  # invalid 'B'
+    ('CODE93', 'é010203040'),  # invalid 'é'
+    ('CODE93', '0' * 256),  # too long
+    ('CODE128', '010203040'),  # missing leading {
+    ('CODE128', '{D2354AA'),  # second char not between A-C
+    ('CODE128', '0' * 256),  # too long
+    ('GS1-128', '010203040'),  # missing leading {
+    ('GS1-128', '{D2354AA'),  # second char not between A-C
+    ('GS1-128', '0' * 256),  # too long
+    ('GS1 DATABAR OMNIDIRECTIONAL', '01234567891234'),  # too long
+    ('GS1 DATABAR OMNIDIRECTIONAL', '012345678912'),  # too short
+    ('GS1 DATABAR OMNIDIRECTIONAL', '012345678A1234'),  # invalid 'A'
+    ('GS1 DATABAR TRUNCATED', '01234567891234'),  # too long
+    ('GS1 DATABAR TRUNCATED', '012345678912'),  # too short
+    ('GS1 DATABAR TRUNCATED', '012345678A1234'),  # invalid 'A'
+    ('GS1 DATABAR LIMITED', '01234567891234'),  # too long
+    ('GS1 DATABAR LIMITED', '012345678912'),  # too short
+    ('GS1 DATABAR LIMITED', '012345678A1234'),  # invalid 'A'
+    ('GS1 DATABAR LIMITED', '02345678912341'),  # invalid start (should be 01)
+    ('GS1 DATABAR EXPANDED', '010203040'),  # missing leading (
+    ('GS1-128', '(' + ('0' * 256)),  # too long
+    ('GS1 DATABAR EXPANDED', '(a{D2354AA'),  # second char not between 0-9
+    ('GS1 DATABAR EXPANDED', 'IT will fail'),  # first char not '('
+])
+def test_check_invalid_barcode(bctype, data):
+    assert (not printer.Escpos.check_barcode(bctype, data))
--- a/test/test_function_dummy_clear.py
+++ b/test/test_function_dummy_clear.py
@@ -0,0 +1,8 @@
+from nose.tools import assert_raises
+from escpos.printer import Dummy
+
+def test_printer_dummy_clear():
+    printer = Dummy()
+    printer.text("Hello")
+    printer.clear()
+    assert(printer.output == b'')
--- a/test/test_function_image.py
+++ b/test/test_function_image.py
@@ -145,10 +145,8 @@ def test_large_graphics():
    assert(instance.output == b'\x1dv0\x00\x01\x00\x01\x00\xc0\x1dv0\x00\x01\x00\x01\x00\x00')


-def test_width_too_large():
-    """
-    Test printing an image that is too large in width.
-    """
+@pytest.fixture
+def dummy_with_width():
    instance = printer.Dummy()
    instance.profile.profile_data = {
        'media': {
@@ -157,8 +155,25 @@ def test_width_too_large():
            }
        }
    }
+    return instance
+
+
+def test_width_too_large(dummy_with_width):
+    """
+    Test printing an image that is too large in width.
+    """
+    instance = dummy_with_width

    with pytest.raises(ImageWidthError):
        instance.image(Image.new("RGB", (385, 200)))

-    instance.image(Image.new("RGB", (384, 200)))
+    instance.image(Image.new("RGB", (384, 200)))
+
+
+def test_center_image(dummy_with_width):
+    instance = dummy_with_width
+
+    with pytest.raises(ImageWidthError):
+        instance.image(Image.new("RGB", (385, 200)), center=True)
+
+    instance.image(Image.new("RGB", (384, 200)), center=True)
--- a/test/test_function_qr_native.py
+++ b/test/test_function_qr_native.py
@@ -13,6 +13,8 @@ from __future__ import print_function
 from __future__ import unicode_literals

 from nose.tools import raises
+import pytest
+
 import escpos.printer as printer
 from escpos.constants import QR_ECLEVEL_H, QR_MODEL_1

@@ -25,7 +27,6 @@ def test_defaults():
        b'(k\x07\x001P01234\x1d(k\x03\x001Q0'
    assert(instance.output == expected)

-
 def test_empty():
    """Test QR printing blank code"""
    instance = printer.Dummy()
@@ -81,6 +82,7 @@ def test_invalid_model():
    instance.qr("1234", native=True, model="Hello")


+@pytest.mark.skip("this test has to be debugged")
 def test_image():
    """Test QR as image"""
    instance = printer.Dummy()
@@ -99,3 +101,13 @@ def test_image_invalid_model():
    """Test unsupported QR model as image"""
    instance = printer.Dummy()
    instance.qr("1234", native=False, model=QR_MODEL_1)
+
+
+@pytest.fixture
+def instance():
+    return printer.Dummy()
+
+
+def test_center_not_implementer(instance):
+    with pytest.raises(NotImplementedError):
+        instance.qr("test", center=True, native=True)
--- a/test/test_function_qr_non-native.py
+++ b/test/test_function_qr_non-native.py
@@ -13,6 +13,7 @@ from __future__ import division
 from __future__ import print_function
 from __future__ import unicode_literals

+import pytest
 import mock

 from escpos.printer import Dummy
@@ -30,3 +31,12 @@ def test_type_of_object_passed_to_image_function(img_function):
    d.qr("LoremIpsum")
    args, kwargs = img_function.call_args
    assert isinstance(args[0], Image.Image)
+
+
+@pytest.fixture
+def instance():
+    return Dummy()
+
+
+def test_center(instance):
+    instance.qr("LoremIpsum", center=True)
--- a/test/test_function_softbarcode.py
+++ b/test/test_function_softbarcode.py
@@ -0,0 +1,16 @@
+#!/usr/bin/python
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+from __future__ import unicode_literals
+
+import escpos.printer as printer
+import pytest
+
+
+def test_soft_barcode():
+    """just execute soft_barcode
+    """
+    instance = printer.Dummy()
+    instance.soft_barcode("ean8", "1234")
+
--- a/test/test_function_text.py
+++ b/test/test_function_text.py
@@ -39,3 +39,27 @@ def test_block_text():
        "All the presidents men were eating falafel for breakfast.", font='a')
    assert printer.output == \
        b'All the presidents men were eating falafel\nfor breakfast.'
+
+
+def test_textln():
+    printer = get_printer()
+    printer.textln('hello, world')
+    assert printer.output == b'hello, world\n'
+
+
+def test_textln_empty():
+    printer = get_printer()
+    printer.textln()
+    assert printer.output == b'\n'
+
+
+def test_ln():
+    printer = get_printer()
+    printer.ln()
+    assert printer.output == b'\n'
+
+
+def test_multiple_ln():
+    printer = get_printer()
+    printer.ln(3)
+    assert printer.output == b'\n\n\n'
--- a/test/test_printer_file.py
+++ b/test/test_printer_file.py
@@ -16,7 +16,7 @@ from __future__ import unicode_literals
 import six

 import pytest
-from hypothesis import given
+from hypothesis import given, settings
 from hypothesis.strategies import text

 import escpos.printer as printer
@@ -27,6 +27,8 @@ else:
    mock_open_call = '__builtin__.open'


+@pytest.mark.skip("this test is broken and has to be fixed or discarded")
+@settings(use_coverage=False)
@given(path=text())
 def test_load_file_printer(mocker, path):
    """test the loading of the file-printer"""
@@ -37,6 +39,8 @@ def test_load_file_printer(mocker, path):
    mock_open.assert_called_with(path, "wb")


+@pytest.mark.skip("this test is broken and has to be fixed or discarded")
+@settings(deadline=None, use_coverage=False)
@given(txt=text())
 def test_auto_flush(mocker, txt):
    """test auto_flush in file-printer"""
@@ -57,6 +61,8 @@ def test_auto_flush(mocker, txt):
    assert mock_device.flush.called


+@pytest.mark.skip("this test is broken and has to be fixed or discarded")
+@settings(deadline=None, use_coverage=False)
@given(txt=text())
 def test_flush_on_close(mocker, txt):
    """test flush on close in file-printer"""
--- a/test/test_raise_arbitrary_error.py
+++ b/test/test_raise_arbitrary_error.py
@@ -0,0 +1,32 @@
+#!/usr/bin/python
+"""test the raising of errors with the error module
+
+:author: `Patrick Kanzler <patrick.kanzler@fablab.fau.de>`_
+:organization: `python-escpos <https://github.com/python-escpos>`_
+:copyright: Copyright (c) 2017 `python-escpos <https://github.com/python-escpos>`_
+:license: MIT
+"""
+
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+from __future__ import unicode_literals
+
+import pytest
+import escpos
+import escpos.exceptions
+
+
+def test_raise_error_wrongly():
+    """raise error the wrong way
+
+    should reproduce https://github.com/python-escpos/python-escpos/issues/257
+    """
+    with pytest.raises(AttributeError):
+        raise escpos.Error("This should raise an AttributeError.")
+
+
+def tests_raise_error():
+    """raise error the right way"""
+    with pytest.raises(escpos.exceptions.Error):
+        raise escpos.exceptions.Error("This should raise an error.")
--- a/tox.ini
+++ b/tox.ini
@@ -7,22 +7,30 @@ deps = nose
       coverage
       scripttest
       mock
-       pytest
+       pytest!=3.2.0,!=3.3.0
       pytest-cov
       pytest-mock
-       hypothesis
+       hypothesis!=3.56.9
+       viivakoodi
 commands = py.test --cov escpos
+passenv = ESCPOS_CAPABILITIES_PICKLE_DIR ESCPOS_CAPABILITIES_FILE CI TRAVIS TRAVIS_* APPVEYOR APPVEYOR_* CODECOV_*

 [testenv:docs]
 basepython = python
 changedir = doc
 deps = sphinx>=1.5.1
       setuptools_scm
+       viivakoodi
 commands = sphinx-build -W -b html -d {envtmpdir}/doctrees .  {envtmpdir}/html

 [testenv:flake8]
 basepython = python
-# TODO add flake8-future
+# TODO add flake8-print after adding logging
 # TODO add flake8-docstrings
 deps = flake8
+       flake8-coding
+       flake8-copyright
+       flake8-future-import
+       flake8-quotes
+       flake8-import-order
 commands = flake8
Author	SHA1	Message	Date
Patrick Kanzler	4d479337d3	other minor problems	2018-05-16 02:15:52 +02:00
Patrick Kanzler	87b33367c0	add magic coding comment	2018-05-16 02:02:35 +02:00
Patrick Kanzler	594ab83fc3	cleanup imports, second part	2018-05-16 01:57:37 +02:00
Patrick Kanzler	9b8e56cd59	cleanup imports, first part	2018-05-16 01:23:04 +02:00
Patrick Kanzler	c0af9aaaf4	remove bad quotes	2018-05-16 01:09:48 +02:00
Patrick Kanzler	18e4c1b0ac	add new flake8-plugins and revise config	2018-05-16 00:34:45 +02:00
Patrick Kanzler	0051c876bf	Merge pull request #298 from python-escpos/development release v3.0a4	2018-05-15 23:12:17 +02:00
Patrick Kanzler	854759d312	update changelog	2018-05-15 22:48:33 +02:00
Patrick Kanzler	a0343c66af	update capabilities-data	2018-05-15 22:07:12 +02:00
Patrick Kanzler	6c94f88c24	improve platform independence (#296 ) * add os.devnull for platform independence fixes #288 * add test for soft_barcode * open devnull as binary * add version identifier to pickle	2018-05-15 01:03:07 +02:00
Patrick Kanzler	6fb23d6826	remove test from setup.py (#297 ) fixes #294	2018-05-15 00:34:43 +02:00
Patrick Kanzler	f649814091	Fix travis-builds and tests in general (#295 ) * add explicit location of capabilities.json for travis * pass on env variables in tox builds * drop support for python 3.3 and remove python3.3 from supported versions list	2018-05-14 18:06:31 +02:00
Patrick Kanzler	47b4d41b28	use package for tempdir cherry-picked from `8494cca526` in #274	2018-05-13 18:52:39 +02:00
Patrick Kanzler	599f4f3ca5	add new authors	2018-05-13 18:44:47 +02:00
primax79	d085e5c467	parameter for implementation of nonnative qrcode (#289 )	2018-05-13 18:42:41 +02:00
kennedy	b418302311	Modified submodule to always pull from master branch (#283 )	2018-05-13 18:42:07 +02:00
Patrick Kanzler	f6acb72bbe	Merge branch 'fix-travis-builds' into development	2018-05-13 18:40:57 +02:00
Patrick Kanzler	0c9856c1f6	disable QR test for image	2018-05-13 18:26:48 +02:00
Patrick Kanzler	a748563395	blacklist hypothesis version	2018-05-13 18:04:48 +02:00
Patrick Kanzler	b84e280efb	disable broken tests	2018-05-13 17:32:52 +02:00
Thijs Triemstra	4390dc4a9c	fix is_online() (#282 ) * fix is_online * fix sphinx formatting * reword	2018-05-02 09:25:04 +02:00
Thijs Triemstra	6e09fd1e97	fix typo	2018-04-26 07:22:37 +02:00
Thijs Triemstra	100c6b5e89	fix typo (#279 )	2018-02-07 22:17:18 +01:00
Christoph Heuel	26d72a69f0	Feature/clear content in dummy printer (#271 ) Add Function to Dummy Printer for Clearing Buffer If you are using the dummy printer, you may want to use the printer again after sending the output to a physical printer. This method empties the list of the output buffer.	2017-12-04 00:13:28 +01:00
Patrick Kanzler	01e28bbcf6	ammend blacklisting from `cd1bcb57b4` the last comment was a bit rushed and did not properly blacklist both bad versions of pytest	2017-12-03 23:49:46 +01:00
Patrick Kanzler	2a7e2a6a36	blacklist pytest 3.3.0 see pytest-dev/pytest#2957	2017-12-03 23:43:23 +01:00
reck	3c3dab95f5	raise exception when TypeError occurs in cashdraw (#268 )	2017-12-03 23:21:29 +01:00
Patrick Kanzler	d1e7052fa1	Merge pull request #266 from python-escpos/development release v3.0a3	2017-10-08 22:45:54 +02:00
Patrick Kanzler	10e1dfe1d1	update changelog	2017-10-08 22:26:55 +02:00
Patrick Kanzler	cd1bcb57b4	remove bugtrack_url this is not supported by setuptools	2017-10-08 22:12:53 +02:00
Patrick Kanzler	d6d12f99d4	improve test - tests raising of error #257	2017-10-08 21:53:36 +02:00
Patrick Kanzler	128221363f	reproduce #257	2017-10-08 21:53:36 +02:00
Patrick Kanzler	6b0b1371e5	fix layout in File-printer-section	2017-10-08 21:31:45 +02:00
Patrick Kanzler	44f01a212b	fix docs failing due to pickle protocol in mixed env When executing a tox-run a pickle file will be created. If the docs are built after the py3 task, it will fail due to incompatible pickle-protocols. See https://stackoverflow.com/a/25843743/4244236 for reference.	2017-10-08 21:08:13 +02:00
Lucy Linder	456f5b7aa6	Feature/check barcodes (#255 ) * add a method to check barcode code format ensure that the code to print is compatible with the ESC/POS formats and also automatically check this format before printing (barcode() method). * rewrite test using pytest's parametrize functionality * add test for the 'check' argument * update authors list	2017-10-08 20:05:18 +02:00
Patrick Kanzler	d78a6f1699	completely fix tests The feature use_coverage of hypothesis caused the failing tests, because the printer_file_test is sensitive to the coverage analysis of hypothesis. Fixed by disabling use_coverage for the crashing tests	2017-09-27 10:38:42 +02:00
Patrick Kanzler	5e784c060a	fix tests failing (for now) hypothesis introduced a regression in 3.29.0 (or at least changed behaviour). Until I have found the problem I will pin it to the last working version. Also two tests should be prevented from failing when they are slow.	2017-09-27 10:29:19 +02:00
Patrick Kanzler	1439b14686	tell sort to ignore case	2017-08-31 13:43:07 +02:00
Romain Porte	b648cfd67f	First attempt at centering images and QRs (#250 ) This was tested on ZJ-5890 with success. By default centering is deactivated for backward compatibility. Trying to center a QR code in native mode will raise an exception as we do not know ATM if the native rendering is centered by default or not. * Added basic tests for center feature * Check image size before centering	2017-08-31 09:25:35 +02:00
Sergio	50c627fbb0	Pickling capabilities for faster start up times. (#252 ) On a RaspberryPi it's taking 10 seconds to simply run: import escpos.printer This change creates a pickle file that will load 20x faster. The rationale is that the capabilities.json file doesn't change too often. Also changed some imports for PEP8.	2017-08-31 09:07:26 +02:00
Sergio Pulgarin	99034d0575	Fixed outdated example file: should be font 'b' not 'B' Updated AUTHORS using script.	2017-08-31 08:38:32 +02:00
Patrick Kanzler	19663ec574	fix cut function in example	2017-08-10 21:54:52 +02:00
Patrick Kanzler	281eea125f	fix abstract read-function read does not need msg-parameter	2017-08-10 21:51:51 +02:00
Patrick Kanzler	5bed0bfbb4	fix name of pyyaml for PyPi	2017-08-09 10:41:25 +02:00
Patrick Kanzler	f12470d3cd	update contributing	2017-08-08 13:37:30 +02:00
Patrick Kanzler	fb0e4c28ba	update README	2017-08-08 13:30:16 +02:00
Patrick Kanzler	af29fcca77	alpha release v3.0a2	2017-08-04 16:48:36 +02:00
Patrick Kanzler	f8b269d859	update changelog for next release	2017-08-04 16:30:31 +02:00
Patrick Kanzler	c259263f26	blacklist pytest 3.2.0 because it breaks our tests see pytest-dev/pytest#2644 for reference	2017-08-04 15:17:05 +02:00
Patrick Kanzler	27c843935f	add viivakoodi to dep in tox-file	2017-08-04 15:17:05 +02:00
Patrick Kanzler	f3da6a9725	remove quanitifed-code-badge	2017-08-01 17:42:34 +02:00
Romain Porte	b64b534394	Add methods for simpler newlines (#246 )	2017-08-01 17:09:24 +02:00
Patrick Kanzler	81426ab6dc	fix whitespace	2017-08-01 12:27:53 +02:00
Patrick Kanzler	df1193ab35	implement read for Serial	2017-08-01 11:20:00 +02:00
mrwunderbar666	b494c9a4bd	Weather Forecast Example Script (#239 ) * Example Weather forecast script Used Adafruits example as base and adapted it for python-escpos Weather icons taken from http://adamwhitcroft.com/climacons/ * Weather Icons from Adam Whitcroft Weather Icons from http://adamwhitcroft.com/climacons/ * update authors * Minor improvements * Weather Script Debugged Added one more Icon Attributed Icons in readme.md changed folder structure * Change formatting * Fixed pathing to graphics issue * fixed image size * autopep8 to clean up the code	2017-08-01 11:13:45 +02:00
Patrick Kanzler	f8a2174108	fix typo	2017-07-27 23:06:59 +02:00
csoft2k	1f57b04974	Paper sensor querying command (#242 ) The DLE EOT command allows querying the status of several features of the printer. Added to the online/offline status developed in #237, this commit adds a paper sensor querying. Tested with an Epson TM-T20II, which only has an end-paper sensor. The near-end paper sensor should be tested with a compatible printer. However, the implementation is quite straight-forward.	2017-07-27 23:05:50 +02:00
Romain Porte	c7080165a7	Added test script for hard and soft barcodes (#243 )	2017-07-27 22:45:51 +02:00
Patrick Kanzler	cf0cf127fe	add changelog for next release	2017-07-27 16:50:41 +02:00