mapnik/tests/python_tests/utilities.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

from nose.plugins.errorclass import ErrorClass, ErrorClassPlugin
from nose.tools import assert_almost_equal

import os, sys, inspect, traceback
import mapnik
from xml.etree import ElementTree

def execution_path(filename):
    return os.path.join(os.path.dirname(sys._getframe(1).f_code.co_filename), filename)

class Todo(Exception):
    pass

class TodoPlugin(ErrorClassPlugin):
    name = "todo"

    todo = ErrorClass(Todo, label='TODO', isfailure=False)

def contains_word(word, bytestring_):
    """
    Checks that a bytestring contains a given word. len(bytestring) should be
    a multiple of len(word).

    >>> contains_word("abcd", "abcd"*5)
    True

    >>> contains_word("ab", "ba"*5)
    False

    >>> contains_word("ab", "ab"*5+"a")
    Traceback (most recent call last):
    ...
    AssertionError: len(bytestring_) not multiple of len(word)
    """
    n = len(word)
    assert len(bytestring_)%n == 0, "len(bytestring_) not multiple of len(word)"
    chunks = [bytestring_[i:i+n] for i in xrange(0, len(bytestring_), n)]
    return word in chunks

def pixel2channels(pixel):
    alpha = (pixel >> 24) & 0xff
    red = pixel & 0xff
    green = (pixel >> 8) & 0xff
    blue = (pixel >> 16) & 0xff
    return red,green,blue,alpha

def pixel2rgba(pixel):
    return 'rgba(%s,%s,%s,%s)' % pixel2channels(pixel)

def get_unique_colors(im):
    pixels = []
    for x in range(im.width()):
        for y in range(im.height()):
            pixel = im.get_pixel(x,y)
            if pixel not in pixels:
                pixels.append(pixel)
    pixels = sorted(pixels)
    return map(pixel2rgba,pixels)

def run_all(iterable):
    failed = 0
    for test in iterable:
        try:
            test()
            sys.stderr.write("\x1b[32m✓ \x1b[m" + test.__name__ + "\x1b[m\n")
        except:
            exc_type, exc_value, exc_tb = sys.exc_info()
            failed += 1
            sys.stderr.write("\x1b[31m✘ \x1b[m" + test.__name__ + "\x1b[m\n")
            for mline in traceback.format_exception_only(exc_type, exc_value):
                for line in mline.rstrip().split("\n"):
                    sys.stderr.write("  \x1b[31m" + line + "\x1b[m\n")
            sys.stderr.write("  Traceback:\n")
            for mline in traceback.format_tb(exc_tb):
                for line in mline.rstrip().split("\n"):
                    if not 'utilities.py' in line and not 'trivial.py' in line and not line.strip() == 'test()':
                        sys.stderr.write("  " + line + "\n")
        sys.stderr.flush()
    return failed

def side_by_side_image(left_im, right_im):
    width = left_im.width() + 1 + right_im.width()
    height = max(left_im.height(), right_im.height())
    im = mapnik.Image(width, height)
    im.blend(0, 0, left_im, 1.0)
    im.blend(left_im.width() + 1, 0, right_im, 1.0)
    return im

def assert_box2d_almost_equal(a, b, msg=None):
    msg = msg or ("%r != %r" % (a, b))
    assert_almost_equal(a.minx, b.minx, msg=msg)
    assert_almost_equal(a.maxx, b.maxx, msg=msg)
    assert_almost_equal(a.miny, b.miny, msg=msg)
    assert_almost_equal(a.maxy, b.maxy, msg=msg)

def datasources_available(map_file, missing_datasources=None):
    '''
    datasources_available

    Determine whether the map file contains only available data source types.

    @param map_file: path of XML map file
    @type map_file: string

    @param missing_datasources: collection of data source type names. if there
                                are unavailable data sources, and a collection
                                reference is provided, it will be populated with
                                the names of the unavailable data sources
    @type missing_datasources: collection reference

    @return: True if all referenced data source types are available,
             otherwise False
    '''
    have_inputs = True
    map_xml = ElementTree.parse(map_file)
    data_source_type_params = map_xml.findall(".//Datasource/Parameter[@name=\"type\"]")
    if data_source_type_params is not None and len(data_source_type_params) > 0:
        for p in data_source_type_params:
            dstype = p.text
            if dstype not in mapnik.DatasourceCache.plugin_names():
                have_inputs = False
                if missing_datasources is not None:
                    missing_datasources.add(dstype)
    return have_inputs