We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
Please add info how to run the skimage unit tests at the end of the installation instructions
I couldn't find instructions how to run the skimage unit tests.

First I tried

```
python -c 'import skimage; skimage.test()
```

which ran 287 tests and gave 16 errors, all the same:

```
ImportError: cannot import name BytesIO
```

Then I tried

```
nosetests --exe skimage
```

which ran 490 tests, no error.

Full output is here: https://gist.github.com/3832077

Apparently it is important to not use `skimage.test()`, but `nosetests` instead?
Could you please add this info somewhere, the first place I would have looked is at the end of http://skimage.org/docs/dev/install.html ( or make "nosetests" or "run tests" in the sphinx search find the appropriate command to run).

Thanks!


--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `skimage/__init__.py`
Content:
```
1 """Image Processing SciKit (Toolbox for SciPy)
2 
3 ``scikits-image`` (a.k.a. ``skimage``) is a collection of algorithms for image
4 processing and computer vision.
5 
6 The main package of ``skimage`` only provides a few utilities for converting
7 between image data types; for most features, you need to import one of the
8 following subpackages:
9 
10 Subpackages
11 -----------
12 color
13     Color space conversion.
14 data
15     Test images and example data.
16 draw
17     Image drawing primitives (lines, text, etc.).
18 exposure
19     Image intensity adjustment (e.g., histogram equalization).
20 feature
21     Feature detection (e.g. texture analysis, corners, etc.).
22 filter
23     Sharpening, edge finding, denoising, etc.
24 graph
25     Graph-theoretic operations, e.g. dynamic programming (shortest paths).
26 io
27     Reading, saving, and displaying images and video.
28 measure
29     Measurement of image properties, e.g., similarity and contours.
30 morphology
31     Morphological operations, e.g. opening or skeletonization.
32 segmentation
33     Splitting an image into self-similar regions.
34 transform
35     Geometric and other transforms, e.g. rotation or the Radon transform.
36 util
37     Generic utilities.
38 
39 Utility Functions
40 -----------------
41 get_log
42     Returns the ``skimage`` log.  Use this to print debug output.
43 img_as_float
44     Convert an image to floating point format, with values in [0, 1].
45 img_as_uint
46     Convert an image to unsigned integer format, with values in [0, 65535].
47 img_as_int
48     Convert an image to signed integer format, with values in [-32768, 32767].
49 img_as_ubyte
50     Convert an image to unsigned byte format, with values in [0, 255].
51 
52 """
53 
54 import os.path as _osp
55 
56 pkg_dir = _osp.abspath(_osp.dirname(__file__))
57 data_dir = _osp.join(pkg_dir, 'data')
58 
59 try:
60     from .version import version as __version__
61 except ImportError:
62     __version__ = "unbuilt-dev"
63 
64 
65 def _setup_test(verbose=False):
66     import functools
67 
68     args = ['', '--exe', '-w', pkg_dir]
69     if verbose:
70         args.extend(['-v', '-s'])
71 
72     try:
73         import nose as _nose
74     except ImportError:
75         def broken_test_func():
76             """This would invoke the skimage test suite, but nose couldn't be
77             imported so the test suite can not run.
78             """
79             raise ImportError("Could not load nose.  Unit tests not available.")
80         return broken_test_func
81     else:
82         f = functools.partial(_nose.run, 'skimage', argv=args)
83         f.__doc__ = 'Invoke the skimage test suite.'
84         return f
85 
86 
87 test = _setup_test()
88 test_verbose = _setup_test(verbose=True)
89 
90 
91 def get_log(name=None):
92     """Return a console logger.
93 
94     Output may be sent to the logger using the `debug`, `info`, `warning`,
95     `error` and `critical` methods.
96 
97     Parameters
98     ----------
99     name : str
100         Name of the log.
101 
102     References
103     ----------
104     .. [1] Logging facility for Python,
105            http://docs.python.org/library/logging.html
106 
107     """
108     import logging
109 
110     if name is None:
111         name = 'skimage'
112     else:
113         name = 'skimage.' + name
114 
115     log = logging.getLogger(name)
116     return log
117 
118 
119 def _setup_log():
120     """Configure root logger.
121 
122     """
123     import logging
124     import sys
125 
126     formatter = logging.Formatter(
127         '%(name)s: %(levelname)s: %(message)s'
128         )
129 
130     try:
131         handler = logging.StreamHandler(stream=sys.stdout)
132     except TypeError:
133         handler = logging.StreamHandler(strm=sys.stdout)
134     handler.setFormatter(formatter)
135 
136     log = get_log()
137     log.addHandler(handler)
138     log.setLevel(logging.WARNING)
139     log.propagate = False
140 
141 _setup_log()
142 
143 from .util.dtype import *
144
```
--- END FILES ---

Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.

Here is an example:

```diff
diff --git a/examples/server_async.py b/examples/server_async.py
--- a/examples/server_async.py
+++ b/examples/server_async.py
@@ -313,4 +313,4 @@
 
 
 if __name__ == "__main__":
-    asyncio.run(run_async_server("."), debug=True)
+    asyncio.run(run_async_server(), debug=True)
diff --git a/examples/server_sync.py b/examples/server_sync.py
--- a/examples/server_sync.py
+++ b/examples/server_sync.py
@@ -313,5 +313,5 @@
 
 
 if __name__ == "__main__":
-    server = run_sync_server(".")
+    server = run_sync_server()
     server.shutdown()

```

diff --git a/skimage/__init__.py b/skimage/__init__.py
--- a/skimage/__init__.py
+++ b/skimage/__init__.py
@@ -65,7 +65,7 @@
 def _setup_test(verbose=False):
     import functools
 
-    args = ['', '--exe', '-w', pkg_dir]
+    args = ['', pkg_dir, '--exe']
     if verbose:
         args.extend(['-v', '-s'])

{"golden_diff": "diff --git a/skimage/__init__.py b/skimage/__init__.py\n--- a/skimage/__init__.py\n+++ b/skimage/__init__.py\n@@ -65,7 +65,7 @@\n def _setup_test(verbose=False):\n     import functools\n \n-    args = ['', '--exe', '-w', pkg_dir]\n+    args = ['', pkg_dir, '--exe']\n     if verbose:\n         args.extend(['-v', '-s'])\n", "issue": "Please add info how to run the skimage unit tests at the end of the installation instructions\nI couldn't find instructions how to run the skimage unit tests.\n\nFirst I tried\n\n```\npython -c 'import skimage; skimage.test()\n```\n\nwhich ran 287 tests and gave 16 errors, all the same:\n\n```\nImportError: cannot import name BytesIO\n```\n\nThen I tried\n\n```\nnosetests --exe skimage\n```\n\nwhich ran 490 tests, no error.\n\nFull output is here: https://gist.github.com/3832077\n\nApparently it is important to not use `skimage.test()`, but `nosetests` instead?\nCould you please add this info somewhere, the first place I would have looked is at the end of http://skimage.org/docs/dev/install.html ( or make \"nosetests\" or \"run tests\" in the sphinx search find the appropriate command to run).\n\nThanks!\n\n", "before_files": [{"content": "\"\"\"Image Processing SciKit (Toolbox for SciPy)\n\n``scikits-image`` (a.k.a. ``skimage``) is a collection of algorithms for image\nprocessing and computer vision.\n\nThe main package of ``skimage`` only provides a few utilities for converting\nbetween image data types; for most features, you need to import one of the\nfollowing subpackages:\n\nSubpackages\n-----------\ncolor\n    Color space conversion.\ndata\n    Test images and example data.\ndraw\n    Image drawing primitives (lines, text, etc.).\nexposure\n    Image intensity adjustment (e.g., histogram equalization).\nfeature\n    Feature detection (e.g. texture analysis, corners, etc.).\nfilter\n    Sharpening, edge finding, denoising, etc.\ngraph\n    Graph-theoretic operations, e.g. dynamic programming (shortest paths).\nio\n    Reading, saving, and displaying images and video.\nmeasure\n    Measurement of image properties, e.g., similarity and contours.\nmorphology\n    Morphological operations, e.g. opening or skeletonization.\nsegmentation\n    Splitting an image into self-similar regions.\ntransform\n    Geometric and other transforms, e.g. rotation or the Radon transform.\nutil\n    Generic utilities.\n\nUtility Functions\n-----------------\nget_log\n    Returns the ``skimage`` log.  Use this to print debug output.\nimg_as_float\n    Convert an image to floating point format, with values in [0, 1].\nimg_as_uint\n    Convert an image to unsigned integer format, with values in [0, 65535].\nimg_as_int\n    Convert an image to signed integer format, with values in [-32768, 32767].\nimg_as_ubyte\n    Convert an image to unsigned byte format, with values in [0, 255].\n\n\"\"\"\n\nimport os.path as _osp\n\npkg_dir = _osp.abspath(_osp.dirname(__file__))\ndata_dir = _osp.join(pkg_dir, 'data')\n\ntry:\n    from .version import version as __version__\nexcept ImportError:\n    __version__ = \"unbuilt-dev\"\n\n\ndef _setup_test(verbose=False):\n    import functools\n\n    args = ['', '--exe', '-w', pkg_dir]\n    if verbose:\n        args.extend(['-v', '-s'])\n\n    try:\n        import nose as _nose\n    except ImportError:\n        def broken_test_func():\n            \"\"\"This would invoke the skimage test suite, but nose couldn't be\n            imported so the test suite can not run.\n            \"\"\"\n            raise ImportError(\"Could not load nose.  Unit tests not available.\")\n        return broken_test_func\n    else:\n        f = functools.partial(_nose.run, 'skimage', argv=args)\n        f.__doc__ = 'Invoke the skimage test suite.'\n        return f\n\n\ntest = _setup_test()\ntest_verbose = _setup_test(verbose=True)\n\n\ndef get_log(name=None):\n    \"\"\"Return a console logger.\n\n    Output may be sent to the logger using the `debug`, `info`, `warning`,\n    `error` and `critical` methods.\n\n    Parameters\n    ----------\n    name : str\n        Name of the log.\n\n    References\n    ----------\n    .. [1] Logging facility for Python,\n           http://docs.python.org/library/logging.html\n\n    \"\"\"\n    import logging\n\n    if name is None:\n        name = 'skimage'\n    else:\n        name = 'skimage.' + name\n\n    log = logging.getLogger(name)\n    return log\n\n\ndef _setup_log():\n    \"\"\"Configure root logger.\n\n    \"\"\"\n    import logging\n    import sys\n\n    formatter = logging.Formatter(\n        '%(name)s: %(levelname)s: %(message)s'\n        )\n\n    try:\n        handler = logging.StreamHandler(stream=sys.stdout)\n    except TypeError:\n        handler = logging.StreamHandler(strm=sys.stdout)\n    handler.setFormatter(formatter)\n\n    log = get_log()\n    log.addHandler(handler)\n    log.setLevel(logging.WARNING)\n    log.propagate = False\n\n_setup_log()\n\nfrom .util.dtype import *\n", "path": "skimage/__init__.py"}], "after_files": [{"content": "\"\"\"Image Processing SciKit (Toolbox for SciPy)\n\n``scikits-image`` (a.k.a. ``skimage``) is a collection of algorithms for image\nprocessing and computer vision.\n\nThe main package of ``skimage`` only provides a few utilities for converting\nbetween image data types; for most features, you need to import one of the\nfollowing subpackages:\n\nSubpackages\n-----------\ncolor\n    Color space conversion.\ndata\n    Test images and example data.\ndraw\n    Image drawing primitives (lines, text, etc.).\nexposure\n    Image intensity adjustment (e.g., histogram equalization).\nfeature\n    Feature detection (e.g. texture analysis, corners, etc.).\nfilter\n    Sharpening, edge finding, denoising, etc.\ngraph\n    Graph-theoretic operations, e.g. dynamic programming (shortest paths).\nio\n    Reading, saving, and displaying images and video.\nmeasure\n    Measurement of image properties, e.g., similarity and contours.\nmorphology\n    Morphological operations, e.g. opening or skeletonization.\nsegmentation\n    Splitting an image into self-similar regions.\ntransform\n    Geometric and other transforms, e.g. rotation or the Radon transform.\nutil\n    Generic utilities.\n\nUtility Functions\n-----------------\nget_log\n    Returns the ``skimage`` log.  Use this to print debug output.\nimg_as_float\n    Convert an image to floating point format, with values in [0, 1].\nimg_as_uint\n    Convert an image to unsigned integer format, with values in [0, 65535].\nimg_as_int\n    Convert an image to signed integer format, with values in [-32768, 32767].\nimg_as_ubyte\n    Convert an image to unsigned byte format, with values in [0, 255].\n\n\"\"\"\n\nimport os.path as _osp\n\npkg_dir = _osp.abspath(_osp.dirname(__file__))\ndata_dir = _osp.join(pkg_dir, 'data')\n\ntry:\n    from .version import version as __version__\nexcept ImportError:\n    __version__ = \"unbuilt-dev\"\n\n\ndef _setup_test(verbose=False):\n    import functools\n\n    args = ['', pkg_dir, '--exe']\n    if verbose:\n        args.extend(['-v', '-s'])\n\n    try:\n        import nose as _nose\n    except ImportError:\n        def broken_test_func():\n            \"\"\"This would invoke the skimage test suite, but nose couldn't be\n            imported so the test suite can not run.\n            \"\"\"\n            raise ImportError(\"Could not load nose.  Unit tests not available.\")\n        return broken_test_func\n    else:\n        f = functools.partial(_nose.run, 'skimage', argv=args)\n        f.__doc__ = 'Invoke the skimage test suite.'\n        return f\n\n\ntest = _setup_test()\ntest_verbose = _setup_test(verbose=True)\n\n\ndef get_log(name=None):\n    \"\"\"Return a console logger.\n\n    Output may be sent to the logger using the `debug`, `info`, `warning`,\n    `error` and `critical` methods.\n\n    Parameters\n    ----------\n    name : str\n        Name of the log.\n\n    References\n    ----------\n    .. [1] Logging facility for Python,\n           http://docs.python.org/library/logging.html\n\n    \"\"\"\n    import logging\n\n    if name is None:\n        name = 'skimage'\n    else:\n        name = 'skimage.' + name\n\n    log = logging.getLogger(name)\n    return log\n\n\ndef _setup_log():\n    \"\"\"Configure root logger.\n\n    \"\"\"\n    import logging\n    import sys\n\n    formatter = logging.Formatter(\n        '%(name)s: %(levelname)s: %(message)s'\n        )\n\n    try:\n        handler = logging.StreamHandler(stream=sys.stdout)\n    except TypeError:\n        handler = logging.StreamHandler(strm=sys.stdout)\n    handler.setFormatter(formatter)\n\n    log = get_log()\n    log.addHandler(handler)\n    log.setLevel(logging.WARNING)\n    log.propagate = False\n\n_setup_log()\n\nfrom .util.dtype import *\n", "path": "skimage/__init__.py"}]}