Update tests.

14 files changed, 279 insertions, 190 deletions

diff --git a/INSTALL b/INSTALL
index 1d4e3fd..9e2b471 100644
--- a/INSTALL
+++ b/INSTALL
@@ -31,8 +31,4 @@ $ python setup.py install
 
 Testing
 -------
-The tests use py.test from pylib
-http://codespeak.net/py/dist/
-
-$ cd test
-$ py.test
+See test/README
diff --git a/examples/cairo_snippets/snippets_png.py b/examples/cairo_snippets/snippets_png.py
index b499c6c..5341979 100755
--- a/examples/cairo_snippets/snippets_png.py
+++ b/examples/cairo_snippets/snippets_png.py
@@ -7,8 +7,8 @@ from math import pi as M_PI  # used by many snippets
 import sys
 
 import cairo
-if not cairo.HAS_PNG_FUNCTIONS:
-    raise SystemExit ('cairo was not compiled with PNG support')
+if not (cairo.HAS_IMAGE_SURFACE and cairo.HAS_PNG_FUNCTIONS):
+  raise SystemExit ('cairo was not compiled with ImageSurface and PNG support')
 
 from snippets import snip_list, snippet_normalize
 
@@ -17,36 +17,36 @@ width, height = 256, 256 # used by snippet_normalize()
 
 
 def do_snippet (snippet):
-    if verbose_mode:
-        print 'processing %s' % snippet,
-
-    surface = cairo.ImageSurface (cairo.FORMAT_ARGB32, width, height)
-    cr = cairo.Context (surface)
-
-    cr.save()
-    try:
-        execfile ('snippets/%s.py' % snippet, globals(), locals())
-    except:
-#        exc_type, exc_value = sys.exc_info()[:2]
-#        print >> sys.stderr, exc_type, exc_value
-        raise
-    else:
-        cr.restore()
-        surface.write_to_png ('snippets/%s.png' % snippet)
-
-    if verbose_mode:
-        print
+  if verbose_mode:
+    print 'processing %s' % snippet,
+
+  surface = cairo.ImageSurface (cairo.FORMAT_ARGB32, width, height)
+  cr = cairo.Context (surface)
+
+  cr.save()
+  try:
+    execfile ('snippets/%s.py' % snippet, globals(), locals())
+  except:
+#    exc_type, exc_value = sys.exc_info()[:2]
+#    print >> sys.stderr, exc_type, exc_value
+    raise
+  else:
+    cr.restore()
+    surface.write_to_png ('snippets/%s.png' % snippet)
+
+  if verbose_mode:
+    print
 
 if __name__ == '__main__':
-    verbose_mode = True
-    if len(sys.argv) > 1 and sys.argv[1] == '-s':
-        verbose_mode = False
-        del sys.argv[1]
-
-    if len(sys.argv) > 1: # do specified snippets
-        snippet_list = sys.argv[1:]
-    else:                 # do all snippets
-        snippet_list = snip_list
-
-    for s in snippet_list:
-        do_snippet (s)
+  verbose_mode = True
+  if len(sys.argv) > 1 and sys.argv[1] == '-s':
+    verbose_mode = False
+    del sys.argv[1]
+
+  if len(sys.argv) > 1: # do specified snippets
+    snippet_list = sys.argv[1:]
+  else:                 # do all snippets
+    snippet_list = snip_list
+
+  for s in snippet_list:
+    do_snippet (s)
diff --git a/test/Makefile.am b/test/Makefile.am
index af0a436..7ca29c4 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -1,5 +1,7 @@
 EXTRA_DIST = \
-	examples_test.py
+        README \
+	api_test.py \
+	examples_test.py \
 	isurface_create_for_data1.py \
 	isurface_create_for_data2.py \
 	isurface_create_from_png.py \
@@ -8,4 +10,3 @@ EXTRA_DIST = \
 	pygame-test2.py \
 	surface_create_for_stream.py \
 	surface_write_to_png.py
-
diff --git a/test/README b/test/README
new file mode 100644
index 0000000..15a9b7d
--- /dev/null
+++ b/test/README
@@ -0,0 +1,13 @@
+pycairo tests
+-------------
+
+The main test files are the '*_test.py' files.
+They use py.test from pylib.
+http://codespeak.net/py/dist/
+
+$ cd test
+$ py.test
+
+The other files are tests that were used to test/develop specific
+functions. They usually require you run the test and then visually examine the
+output.
diff --git a/test/api_test.py b/test/api_test.py
index 6a8db8c..47d3520 100644
--- a/test/api_test.py
+++ b/test/api_test.py
@@ -14,41 +14,77 @@ import py.test as test
 
 
 def test_context():
-    pass
+  if cairo.HAS_IMAGE_SURFACE:
+    f, w, h = cairo.FORMAT_ARGB32, 100, 100
+    s = cairo.ImageSurface(f, w, h)
+    ctx = cairo.Context(s)
+    ctx.set_source_rgb(1.0, 1.0, 1.0)
+    ctx.set_operator(cairo.OPERATOR_SOURCE)
+    ctx.paint()
+
 
 def test_matrix():
-    pass
+  m = cairo.Matrix()
+  m.rotate(10)
+  m.scale(1.5, 2.5)
+  m.translate(10, 20)
+
 
 def test_path():
-    pass
+  # AttributeError: 'module' object has no attribute 'Path'
+  test.raises(AttributeError, "p = cairo.Path()")
+  # see examples/warpedtext.py
+
+
+def test_pattern():
+  # TypeError: The Pattern type cannot be instantiated
+  test.raises(TypeError, "p = cairo.Pattern()")
+
+  r,g,b,a = 0.1, 0.2, 0.3, 0.4
+  p = cairo.SolidPattern(r,g,b,a)
+  assert p.get_rgba() == (r,g,b,a)
+
+  # SurfacePattern
+
+  # TypeError: The Gradient type cannot be instantiated
+  test.raises(TypeError, "p = cairo.Gradient()")
+
+  x0,y0,x1,y1 = 0.0, 0.0, 0.0, 1.0
+  p = cairo.LinearGradient(x0,y0,x1,y1)
+  assert p.get_linear_points() == (x0,y0,x1,y1)
+  p.add_color_stop_rgba(1, 0, 0, 0, 1)
+  p.add_color_stop_rgba(0, 1, 1, 1, 1)
 
-def test_patterns():
-    pass
+  cx0, cy0, radius0, cx1, cy1, radius1 = 1.0, 1.0, 1.0, 2.0, 2.0, 1.0
+  p = cairo.RadialGradient(cx0, cy0, radius0, cx1, cy1, radius1)
+  assert p.get_radial_circles() == (cx0, cy0, radius0, cx1, cy1, radius1)
+  p.add_color_stop_rgba(0, 1, 1, 1, 1)
+  p.add_color_stop_rgba(1, 0, 0, 0, 1)
 
 
-def test_surfaces():
-    # The Surface type cannot be instantiated
-    test.raises(TypeError, "s = cairo.Surface()")
+def test_surface():
+  # TypeError: The Surface type cannot be instantiated
+  test.raises(TypeError, "s = cairo.Surface()")
 
-    if cairo.HAS_IMAGE_SURFACE:
-        f, w, h = cairo.FORMAT_ARGB32, 100, 100
-        s = cairo.ImageSurface(f, w, h)
-        assert s.get_format() == f
-        assert s.get_width() == w
-        assert s.get_height() == h
+  if cairo.HAS_IMAGE_SURFACE:
+    f, w, h = cairo.FORMAT_ARGB32, 100, 100
+    s = cairo.ImageSurface(f, w, h)
+    assert s.get_format() == f
+    assert s.get_width() == w
+    assert s.get_height() == h
 
-    if cairo.HAS_PDF_SURFACE:
-        f, w, h = tfi.TemporaryFile(mode='w+b'), 100, 100
-        s = cairo.PDFSurface(f, w, h)
+  if cairo.HAS_PDF_SURFACE:
+    f, w, h = tfi.TemporaryFile(mode='w+b'), 100, 100
+    s = cairo.PDFSurface(f, w, h)
 
-    if cairo.HAS_PS_SURFACE:
-        f, w, h = tfi.TemporaryFile(mode='w+b'), 100, 100
-        s = cairo.PSSurface(f, w, h)
+  if cairo.HAS_PS_SURFACE:
+    f, w, h = tfi.TemporaryFile(mode='w+b'), 100, 100
+    s = cairo.PSSurface(f, w, h)
 
-    if cairo.HAS_SVG_SURFACE:
-        f, w, h = tfi.TemporaryFile(mode='w+b'), 100, 100
-        s = cairo.SVGSurface(f, w, h)
+  if cairo.HAS_SVG_SURFACE:
+    f, w, h = tfi.TemporaryFile(mode='w+b'), 100, 100
+    s = cairo.SVGSurface(f, w, h)
 
 
 def test_text():
-    pass
+  pass
diff --git a/test/examples_test.py b/test/examples_test.py
index f5fe924..ab85514 100644
--- a/test/examples_test.py
+++ b/test/examples_test.py
@@ -8,22 +8,26 @@ import os
 import os.path
 import subprocess
 
+import cairo
 #import py.test as test
 
 
-def test_examples():
-    '''run non-gui example scripts and check they exit successfully.
-    '''
-    os.chdir(os.path.join(os.path.dirname(__file__), '..', 'examples'))
-    for f in (x for x in os.listdir('.') if x.endswith('.py')):
-        retcode = subprocess.call('python %s' % f, shell=True)
-        assert retcode == 0, 'Error: {0} retcode == {1}'.format(f, retcode)
-
-
-def test_snippets_png():
-    '''run all snippets in png mode and check they exit successfully.
-    '''
-    os.chdir(os.path.join(os.path.dirname(__file__), '..', 'examples',
-                          'cairo_snippets'))
-    retcode = subprocess.call('python snippets_png.py -s', shell=True)
+def test_snippets():
+  '''Run all snippets in png,pdf,ps,svg mode and check they exit successfully.
+  This will create *.{pdf,png,ps,svg} output files in
+  examples/cairo_snippets/snippets/
+  '''
+  def doSnippets(name):
+    retcode = subprocess.call('python %s -s' % name, shell=True)
     assert retcode == 0, 'Error: retcode == {0}'.format(retcode)
+
+  os.chdir(os.path.join(os.path.dirname(__file__), '..', 'examples',
+                        'cairo_snippets'))
+  if cairo.HAS_PDF_SURFACE:
+    doSnippets('snippets_pdf.py')
+  if cairo.HAS_IMAGE_SURFACE and cairo.HAS_PNG_FUNCTIONS:
+    doSnippets('snippets_png.py')
+  if cairo.HAS_PS_SURFACE:
+    doSnippets('snippets_ps.py')
+  if cairo.HAS_SVG_SURFACE:
+    doSnippets('snippets_svg.py')
diff --git a/test/isurface_create_for_data1.py b/test/isurface_create_for_data1.py
index c497991..867fde4 100755
--- a/test/isurface_create_for_data1.py
+++ b/test/isurface_create_for_data1.py
@@ -3,25 +3,30 @@
 """
 
 import array
+import tempfile
 
 import cairo
 
-dir_ = "/tmp/"
+if not (cairo.HAS_IMAGE_SURFACE and cairo.HAS_PNG_FUNCTIONS):
+  raise SystemExit ('cairo was not compiled with ImageSurface and PNG support')
+
+h, fileName = tempfile.mkstemp(prefix='pycairo_', suffix='.png')
 width, height = 255, 255
 data = array.array('B', [0] * width * height * 4)
 
 for y in range(height):
-    for x in range(width):
-        offset = (x + (y * width)) * 4
-        alpha = y
+  for x in range(width):
+    offset = (x + (y * width)) * 4
+    alpha = y
 
-        # cairo.FORMAT_ARGB32 uses pre-multiplied alpha
-        data[offset+0] = int(x * alpha/255.0) # B
-        data[offset+1] = int(y * alpha/255.0) # G
-        data[offset+2] = 0                    # R
-        data[offset+3] = alpha                # A
+    # cairo.FORMAT_ARGB32 uses pre-multiplied alpha
+    data[offset+0] = int(x * alpha/255.0) # B
+    data[offset+1] = int(y * alpha/255.0) # G
+    data[offset+2] = 0                    # R
+    data[offset+3] = alpha                # A
 
 surface = cairo.ImageSurface.create_for_data(data, cairo.FORMAT_ARGB32,
                                              width, height)
 ctx = cairo.Context(surface)
-surface.write_to_png(dir_ + 'for_data1.png')
+surface.write_to_png(fileName)
+print "see %s output file" % fileName
diff --git a/test/isurface_create_for_data2.py b/test/isurface_create_for_data2.py
index 88b4c5c..c4f290b 100755
--- a/test/isurface_create_for_data2.py
+++ b/test/isurface_create_for_data2.py
@@ -1,26 +1,30 @@
 #!/usr/bin/env python
 """test cairo.ImageSurface.create_for_data() with a numpy array
 """
+import tempfile
 
 import cairo
-
 import numpy
 
-dir_ = "/tmp/"
+if not (cairo.HAS_IMAGE_SURFACE and cairo.HAS_PNG_FUNCTIONS):
+  raise SystemExit ('cairo was not compiled with ImageSurface and PNG support')
+
+h, fileName = tempfile.mkstemp(prefix='pycairo_', suffix='.png')
 width, height = 255, 255
 data = numpy.ndarray (shape=(height,width,4), dtype=numpy.uint8)
 
 for x in range(width):
-    for y in range(height):
-        alpha = y
+  for y in range(height):
+    alpha = y
 
-        # cairo.FORMAT_ARGB32 uses pre-multiplied alpha
-        data[y][x][0] = int(x * alpha/255.0)
-        data[y][x][1] = int(y * alpha/255.0)
-        data[y][x][2] = 0
-        data[y][x][3] = alpha
+    # cairo.FORMAT_ARGB32 uses pre-multiplied alpha
+    data[y][x][0] = int(x * alpha/255.0) # B
+    data[y][x][1] = int(y * alpha/255.0) # G
+    data[y][x][2] = 0                    # R
+    data[y][x][3] = alpha                # A
 
 surface = cairo.ImageSurface.create_for_data (data, cairo.FORMAT_ARGB32,
                                               width, height)
 ctx = cairo.Context(surface)
-surface.write_to_png(dir_ + 'for_data2.png')
+surface.write_to_png(fileName)
+print "see %s output file" % fileName
diff --git a/test/isurface_create_from_png.py b/test/isurface_create_from_png.py
index 951acb3..129016d 100755
--- a/test/isurface_create_from_png.py
+++ b/test/isurface_create_from_png.py
@@ -1,37 +1,56 @@
 #!/usr/bin/env python
-# test cairo.ImageSurface.create_from_png()
+'''test cairo.ImageSurface.create_from_png() and
+        cairo.Surface.write_to_png()
+'''
+
+import os
+import tempfile
 
 import cairo
 
-surface = cairo.ImageSurface.create_from_png("/tmp/warpedtext.png")
+if not (cairo.HAS_IMAGE_SURFACE and cairo.HAS_PNG_FUNCTIONS):
+  raise SystemExit ('cairo was not compiled with ImageSurface and PNG support')
+
+inFileName = os.path.join(os.path.dirname(__file__), '..', 'examples',
+                          'cairo_snippets', 'data', 'romedalen.png')
+surface = cairo.ImageSurface.create_from_png(inFileName)
 
 # write to filename
-surface.write_to_png("/tmp/t1.png")
+_, outFileName = tempfile.mkstemp(prefix='pycairo_', suffix='.png')
+surface.write_to_png(outFileName)
+print "see %s output file" % outFileName
 
 # write to file object
-f2=file("/tmp/t2.png", "w")
-surface.write_to_png(f2)
-f2.close()
+h, outFileName = tempfile.mkstemp(prefix='pycairo_', suffix='.png')
+os.close(h)
+f=file(outFileName, "w")
+surface.write_to_png(f)
+f.close()
+print "see %s output file" % outFileName
 
 # write to object that has a "write" method
 import StringIO
-buffer = StringIO.StringIO()
-surface.write_to_png(buffer)
-png_string = buffer.getvalue()
-buffer.close()
-f3=file("/tmp/t3.png", "w")
-f3.write(png_string)
-f3.close()
+_, outFileName = tempfile.mkstemp(prefix='pycairo_', suffix='.png')
+buf = StringIO.StringIO()
+surface.write_to_png(buf)
+png_string = buf.getvalue()
+buf.close()
+f=file(outFileName, "w")
+f.write(png_string)
+f.close()
+print "see %s output file" % outFileName
 
 # write to object that has a "write" method
+_, outFileName = tempfile.mkstemp(prefix='pycairo_', suffix='.png')
 import cStringIO
-buffer = cStringIO.StringIO()
-surface.write_to_png(buffer)
-png_string = buffer.getvalue()
-buffer.close()
-f4=file("/tmp/t4.png", "w")
-f4.write(png_string)
-f4.close()
+buf = cStringIO.StringIO()
+surface.write_to_png(buf)
+png_string = buf.getvalue()
+buf.close()
+f=file(outFileName, "w")
+f.write(png_string)
+f.close()
+print "see %s output file" % outFileName
 
 # error test - to check the error message, should raise TypeError
 #surface.write_to_png(101)
diff --git a/test/isurface_get_data.py b/test/isurface_get_data.py
index c19a17e..f2662d4 100755
--- a/test/isurface_get_data.py
+++ b/test/isurface_get_data.py
@@ -2,11 +2,14 @@
 """
 Test ImageSurface.get_data()
 """
+import tempfile
 
 import cairo
 import numpy
 
-dir_ = "/tmp/"
+if not (cairo.HAS_IMAGE_SURFACE and cairo.HAS_PNG_FUNCTIONS):
+  raise SystemExit ('cairo was not compiled with ImageSurface and PNG support')
+
 w, h = 128, 128
 
 surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, w, h)
@@ -25,7 +28,9 @@ ctx.close_path()
 ctx.set_source_rgb(0, 0, 0)  # black
 ctx.set_line_width(15)
 ctx.stroke()
-surface.write_to_png(dir_ + "get_data_test1.png")
+_, outFileName = tempfile.mkstemp(prefix='pycairo_', suffix='.png')
+surface.write_to_png(outFileName)
+print "see %s output file" % outFileName
 
 # modify surface using numpy
 buf = surface.get_data()
@@ -40,4 +45,6 @@ a = numpy.ndarray(shape=(w,h,4), dtype=numpy.uint8, buffer=buf)
 a[:,40,0] = 255  # byte 0 is blue on little-endian systems
 a[:,40,1] = 0
 a[:,40,2] = 0
-surface.write_to_png(dir_ + "get_data_test2.png")
+_, outFileName = tempfile.mkstemp(prefix='pycairo_', suffix='.png')
+surface.write_to_png(outFileName)
+print "see %s output file" % outFileName
diff --git a/test/pygame-test1.py b/test/pygame-test1.py
index 25871e5..bd96b88 100755
--- a/test/pygame-test1.py
+++ b/test/pygame-test1.py
@@ -11,21 +11,21 @@ import cairo
 import pygame
 
 def draw(surface):
-    x,y, radius = (250,250, 200)
-    ctx = cairo.Context(surface)
-    ctx.set_line_width(15)
-    ctx.arc(x, y, radius, 0, 2.0 * math.pi)
-    ctx.set_source_rgb(0.8, 0.8, 0.8)
-    ctx.fill_preserve()
-    ctx.set_source_rgb(1, 1, 1)
-    ctx.stroke()
+  x,y, radius = (250,250, 200)
+  ctx = cairo.Context(surface)
+  ctx.set_line_width(15)
+  ctx.arc(x, y, radius, 0, 2.0 * math.pi)
+  ctx.set_source_rgb(0.8, 0.8, 0.8)
+  ctx.fill_preserve()
+  ctx.set_source_rgb(1, 1, 1)
+  ctx.stroke()
 
 def input(events):
-   for event in events:
-      if event.type == pygame.QUIT:
-         sys.exit(0)
-      else:
-         print event
+ for event in events:
+  if event.type == pygame.QUIT:
+      sys.exit(0)
+  else:
+      print event
 
 
 Width, Height = 512, 512
@@ -45,7 +45,7 @@ screen.blit(image, (0,0))
 pygame.display.flip()
 
 while True:
-   input(pygame.event.get())
+  input(pygame.event.get())
 
 
 """
diff --git a/test/pygame-test2.py b/test/pygame-test2.py
index 9ebc1ae..bec32de 100755
--- a/test/pygame-test2.py
+++ b/test/pygame-test2.py
@@ -11,21 +11,21 @@ import cairo
 import pygame
 
 def draw(surface):
-    x,y, radius = (250,250, 200)
-    ctx = cairo.Context(surface)
-    ctx.set_line_width(15)
-    ctx.arc(x, y, radius, 0, 2.0 * math.pi)
-    ctx.set_source_rgb(0.8, 0.8, 0.8)
-    ctx.fill_preserve()
-    ctx.set_source_rgb(1, 1, 1)
-    ctx.stroke()
+  x,y, radius = (250,250, 200)
+  ctx = cairo.Context(surface)
+  ctx.set_line_width(15)
+  ctx.arc(x, y, radius, 0, 2.0 * math.pi)
+  ctx.set_source_rgb(0.8, 0.8, 0.8)
+  ctx.fill_preserve()
+  ctx.set_source_rgb(1, 1, 1)
+  ctx.stroke()
 
 def input(events):
-   for event in events:
-      if event.type == pygame.QUIT:
-         sys.exit(0)
-      else:
-         print event
+ for event in events:
+  if event.type == pygame.QUIT:
+    sys.exit(0)
+  else:
+    print event
 
 
 Width, Height = 512, 512
@@ -46,4 +46,4 @@ screen.blit(image, (0,0))
 pygame.display.flip()
 
 while True:
-   input(pygame.event.get())
+  input(pygame.event.get())
diff --git a/test/surface_create_for_stream.py b/test/surface_create_for_stream.py
index 210badd..61997e0 100755
--- a/test/surface_create_for_stream.py
+++ b/test/surface_create_for_stream.py
@@ -13,19 +13,19 @@ import cairo
 
 
 class C(object):
-    """a file-like object (for testing), it simulates sys.stdout
-    """
-    def __init__ (self):
-        self.closed = False
+  """a file-like object (for testing), it simulates sys.stdout
+  """
+  def __init__ (self):
+    self.closed = False
 
-    def write(self, s):
-        """just echo to stdout, without newlines"""
-        if self.closed:
-            raise ValueError ("I/O operation on closed file")
-        sys.stdout.write (s)
+  def write(self, s):
+    """just echo to stdout, without newlines"""
+    if self.closed:
+      raise ValueError ("I/O operation on closed file")
+    sys.stdout.write(s)
 
-    def close(self):
-        self.closed = True
+  def close(self):
+    self.closed = True
 
 
 # a selection of possible args to surface.write_to_png()
@@ -40,36 +40,36 @@ fo = file('/tmp/f.svg', 'w')
 
 WIDTH, HEIGHT  = 256, 256
 
-#surface = cairo.PDFSurface (fo, WIDTH, HEIGHT)
-#surface = cairo.PSSurface (fo, WIDTH, HEIGHT)
-surface = cairo.SVGSurface (fo, WIDTH, HEIGHT)
+#surface = cairo.PDFSurface(fo, WIDTH, HEIGHT)
+#surface = cairo.PSSurface(fo, WIDTH, HEIGHT)
+surface = cairo.SVGSurface(fo, WIDTH, HEIGHT)
 
 #sys.stdout.write ('1\n'); sys.stdout.flush()
-ctx = cairo.Context (surface)
+ctx = cairo.Context(surface)
 
 #del fo  # test that 'fo' is referenced to keep it alive
 #gc.collect()
 
 #fo.close()  # this should cause: ValueError: I/O operation on closed file
 
-ctx.scale (WIDTH/1.0, HEIGHT/1.0)
+ctx.scale(WIDTH/1.0, HEIGHT/1.0)
 
-pat = cairo.LinearGradient (0.0, 0.0, 0.0, 1.0)
-pat.add_color_stop_rgba (1, 0, 0, 0, 1)
-pat.add_color_stop_rgba (0, 1, 1, 1, 1)
+pat = cairo.LinearGradient(0.0, 0.0, 0.0, 1.0)
+pat.add_color_stop_rgba(1, 0, 0, 0, 1)
+pat.add_color_stop_rgba(0, 1, 1, 1, 1)
 
-ctx.rectangle (0,0,1,1)
-ctx.set_source (pat)
-ctx.fill ()
+ctx.rectangle(0,0,1,1)
+ctx.set_source(pat)
+ctx.fill()
 
-pat = cairo.RadialGradient (0.45, 0.4, 0.1,
+pat = cairo.RadialGradient(0.45, 0.4, 0.1,
                             0.4,  0.4, 0.5)
-pat.add_color_stop_rgba (0, 1, 1, 1, 1)
-pat.add_color_stop_rgba (1, 0, 0, 0, 1)
+pat.add_color_stop_rgba(0, 1, 1, 1, 1)
+pat.add_color_stop_rgba(1, 0, 0, 0, 1)
 
-ctx.set_source (pat)
-ctx.arc (0.5, 0.5, 0.3, 0, 2 * math.pi)
-ctx.fill ()
+ctx.set_source(pat)
+ctx.arc(0.5, 0.5, 0.3, 0, 2 * math.pi)
+ctx.fill()
 
 ctx.show_page()
 surface.finish()
diff --git a/test/surface_write_to_png.py b/test/surface_write_to_png.py
index f4ba83b..61674f4 100755
--- a/test/surface_write_to_png.py
+++ b/test/surface_write_to_png.py
@@ -11,20 +11,24 @@ import StringIO
 import cairo
 
 
+if not (cairo.HAS_IMAGE_SURFACE and cairo.HAS_PNG_FUNCTIONS):
+  raise SystemExit ('cairo was not compiled with ImageSurface and PNG support')
+
+
 class C(object):
-    """a file-like object (for testing), it simulates sys.stdout
-    """
-    def __init__(self):
-        self.closed = False
+  """a file-like object (for testing), it simulates sys.stdout
+  """
+  def __init__(self):
+    self.closed = False
 
-    def write(self, s):
-        """just echo to stdout, without newlines"""
-        if self.closed:
-            raise ValueError("I/O operation on closed file")
-        sys.stdout.write(s)
+  def write(self, s):
+    """just echo to stdout, without newlines"""
+    if self.closed:
+      raise ValueError("I/O operation on closed file")
+    sys.stdout.write(s)
 
-    def close(self):
-        self.closed = True
+  def close(self):
+    self.closed = True
 
 
 WIDTH, HEIGHT  = 256, 256
@@ -59,7 +63,7 @@ fo = file('/tmp/f.png', 'w')
 #fo = sys.stdout
 #fo = C()
 
-fo.close()  # this should cause: ValueError: I/O operation on closed file
+#fo.close()  # this should cause: ValueError: I/O operation on closed file
 surface.write_to_png(fo)
 
 # for testing StringIO: get data and write to file