ScriptHost.python_chdir() - Code Metrics - Inspection of "Correctly change the working directory in python" - neovim/python-client - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Pull Request — master (#296)

unknown

created 2018-01-19 10:53 UTC

ScriptHost.python_chdir() A

↳ Parent: ScriptHost

Complexity

Conditions

Size

Total Lines

Duplication

Lines	0
Ratio	0 %

Code Coverage

Tests	2
CRAP Score	1.037

Importance

Changes	1
Bugs	0	Features	0

Metric	Value
cc	1
c	1
b	0
f	0
dl	0
loc	4
ccs	2
cts	3
cp	0.6667
crap	1.037
rs	10

"""Legacy python/python3-vim emulation."""
import imp
import io
import logging
import os
import sys

from .decorators import plugin, rpc_export
from ..api import Nvim, walk
from ..msgpack_rpc import ErrorResponse
from ..util import format_exc_skip

__all__ = ('ScriptHost',)


logger = logging.getLogger(__name__)
debug, info, warn = (logger.debug, logger.info, logger.warn,)

IS_PYTHON3 = sys.version_info >= (3, 0)

if IS_PYTHON3:
    basestring = str

    if sys.version_info >= (3, 4):
        from importlib.machinery import PathFinder

    PYTHON_SUBDIR = 'python3'
else:
    PYTHON_SUBDIR = 'python2'


@plugin
class ScriptHost(object):

    """Provides an environment for running python plugins created for Vim."""

    def __init__(self, nvim):
        """Initialize the legacy python-vim environment."""
        self.setup(nvim)
        # context where all code will run
        self.module = imp.new_module('__main__')
        nvim.script_context = self.module
        # it seems some plugins assume 'sys' is already imported, so do it now
        exec('import sys', self.module.__dict__)

        self.legacy_vim = LegacyVim.from_nvim(nvim)
        sys.modules['vim'] = self.legacy_vim

    def setup(self, nvim):
        """Setup import hooks and global streams.

        This will add import hooks for importing modules from runtime
        directories and patch the sys module so 'print' calls will be
        forwarded to Nvim.
        """
        self.nvim = nvim
        info('install import hook/path')
        self.hook = path_hook(nvim)
        sys.path_hooks.append(self.hook)
        nvim.VIM_SPECIAL_PATH = '_vim_path_'
        sys.path.append(nvim.VIM_SPECIAL_PATH)
        info('redirect sys.stdout and sys.stderr')
        self.saved_stdout = sys.stdout
        self.saved_stderr = sys.stderr
        sys.stdout = RedirectStream(lambda data: nvim.out_write(data))

        sys.stderr = RedirectStream(lambda data: nvim.err_write(data))

        # Setup the DirChanged listener
        cid = nvim.channel_id
        cmd = 'au DirChanged * call rpcrequest(%d, "python_chdir", v:event)' \
                % cid
        nvim.command(cmd)

    def teardown(self):
        """Restore state modified from the `setup` call."""
        nvim = self.nvim
        info('uninstall import hook/path')
        sys.path.remove(nvim.VIM_SPECIAL_PATH)
        sys.path_hooks.remove(self.hook)
        info('restore sys.stdout and sys.stderr')
        sys.stdout = self.saved_stdout
        sys.stderr = self.saved_stderr

    @rpc_export('python_execute', sync=True)
    def python_execute(self, script, range_start, range_stop):
        """Handle the `python` ex command."""
        self._set_current_range(range_start, range_stop)
        try:
            exec(script, self.module.__dict__)

        except Exception:
            raise ErrorResponse(format_exc_skip(1))

    @rpc_export('python_execute_file', sync=True)
    def python_execute_file(self, file_path, range_start, range_stop):
        """Handle the `pyfile` ex command."""
        self._set_current_range(range_start, range_stop)
        with open(file_path) as f:
            script = compile(f.read(), file_path, 'exec')
            try:
                exec(script, self.module.__dict__)

            except Exception:
                raise ErrorResponse(format_exc_skip(1))

    @rpc_export('python_do_range', sync=True)
    def python_do_range(self, start, stop, code):
        """Handle the `pydo` ex command."""
        self._set_current_range(start, stop)
        nvim = self.nvim
        start -= 1
        fname = '_vim_pydo'

        # define the function
        function_def = 'def %s(line, linenr):\n %s' % (fname, code,)
        exec(function_def, self.module.__dict__)

        # get the function
        function = self.module.__dict__[fname]
        while start < stop:
            # Process batches of 5000 to avoid the overhead of making multiple
            # API calls for every line. Assuming an average line length of 100
            # bytes, approximately 488 kilobytes will be transferred per batch,
            # which can be done very quickly in a single API call.
            sstart = start
            sstop = min(start + 5000, stop)
            lines = nvim.current.buffer.api.get_lines(sstart, sstop, True)

            exception = None
            newlines = []
            linenr = sstart + 1
            for i, line in enumerate(lines):

                result = function(line, linenr)
                if result is None:
                    # Update earlier lines, and skip to the next
                    if newlines:
                        end = sstart + len(newlines) - 1
                        nvim.current.buffer.api.set_lines(sstart, end,
                                                          True, newlines)
                    sstart += len(newlines) + 1
                    newlines = []
                    pass

                elif isinstance(result, basestring):
                    newlines.append(result)
                else:
                    exception = TypeError('pydo should return a string ' +
                                          'or None, found %s instead'
                                          % result.__class__.__name__)
                    break
                linenr += 1

            start = sstop
            if newlines:
                end = sstart + len(newlines)
                nvim.current.buffer.api.set_lines(sstart, end, True, newlines)
            if exception:
                raise exception

        # delete the function
        del self.module.__dict__[fname]

    @rpc_export('python_eval', sync=True)
    def python_eval(self, expr):
        """Handle the `pyeval` vim function."""
        return eval(expr, self.module.__dict__)


    @rpc_export('python_chdir', sync=True)
    def python_chdir(self, args):
class Foo:
    def some_method(self, x, y):
        return x + y;
        """Handle working directory changes."""
        os.chdir(args['cwd'])

    def _set_current_range(self, start, stop):
        current = self.legacy_vim.current
        current.range = current.buffer.range(start, stop)


class RedirectStream(io.IOBase):
    def __init__(self, redirect_handler):
        self.redirect_handler = redirect_handler

    def write(self, data):
        self.redirect_handler(data)

    def writelines(self, seq):
        self.redirect_handler('\n'.join(seq))


if IS_PYTHON3:
    num_types = (int, float)
else:
    num_types = (int, long, float)



def num_to_str(obj):
    if isinstance(obj, num_types):
        return str(obj)
    else:
        return obj


class LegacyVim(Nvim):
    def eval(self, expr):
        obj = self.request("vim_eval", expr)
        return walk(num_to_str, obj)


# This was copied/adapted from nvim-python help
def path_hook(nvim):
    def _get_paths():
        return discover_runtime_directories(nvim)

    def _find_module(fullname, oldtail, path):
        idx = oldtail.find('.')
        if idx > 0:
            name = oldtail[:idx]
            tail = oldtail[idx + 1:]
            fmr = imp.find_module(name, path)
            module = imp.find_module(fullname[:-len(oldtail)] + name, *fmr)
            return _find_module(fullname, tail, module.__path__)

        else:
            return imp.find_module(fullname, path)

    class VimModuleLoader(object):
        def __init__(self, module):
            self.module = module

        def load_module(self, fullname, path=None):

            # Check sys.modules, required for reload (see PEP302).
            if fullname in sys.modules:
                return sys.modules[fullname]
            return imp.load_module(fullname, *self.module)

    class VimPathFinder(object):
        @staticmethod
        def find_module(fullname, path=None):
            """Method for Python 2.7 and 3.3."""
            try:
                return VimModuleLoader(
                    _find_module(fullname, fullname, path or _get_paths()))
            except ImportError:
                return None

        @staticmethod
        def find_spec(fullname, path=None, target=None):
            """Method for Python 3.4+."""
            return PathFinder.find_spec(fullname, path or _get_paths(), target)

    def hook(path):
        if path == nvim.VIM_SPECIAL_PATH:
            return VimPathFinder
        else:
            raise ImportError

    return hook


def discover_runtime_directories(nvim):
    rv = []
    for rtp in nvim.list_runtime_paths():
        if not os.path.exists(rtp):
            continue
        for subdir in ['pythonx', PYTHON_SUBDIR]:
            path = os.path.join(rtp, subdir)
            if os.path.exists(path):
                rv.append(path)
    return rv


1		"""Legacy python/python3-vim emulation."""
2	5	import imp
3	5	import io
4	5	import logging
5	5	import os
6	5	import sys
7
8	5	from .decorators import plugin, rpc_export
9	5	from ..api import Nvim, walk
10	5	from ..msgpack_rpc import ErrorResponse
11	5	from ..util import format_exc_skip
12
13	5	__all__ = ('ScriptHost',)
14
15
16	5	logger = logging.getLogger(__name__)
17	5	debug, info, warn = (logger.debug, logger.info, logger.warn,)
18
19	5	IS_PYTHON3 = sys.version_info >= (3, 0)
20
21	5	if IS_PYTHON3:
22	3	basestring = str
23
24	3	if sys.version_info >= (3, 4):
25	2	from importlib.machinery import PathFinder
26
27		PYTHON_SUBDIR = 'python3'
28	5	else:
29	5	PYTHON_SUBDIR = 'python2'
30
31
32		@plugin
33	5	class ScriptHost(object):
34
35		"""Provides an environment for running python plugins created for Vim."""
36
37		def __init__(self, nvim):
38		"""Initialize the legacy python-vim environment."""
39		self.setup(nvim)
40		# context where all code will run
41		self.module = imp.new_module('__main__')
42		nvim.script_context = self.module
43		# it seems some plugins assume 'sys' is already imported, so do it now
44	5	exec('import sys', self.module.__dict__)
		0 ignored issues – show Coding Style Security introduced 2016-03-06 13:35 UTC by Report Bug Copy Issue Report The use of `exec` is discouraged. Execution of dynamic code might introduce security vulnerabilities. It is generally recommended to use this feature with care and only when necessary. Loading history...
45		self.legacy_vim = LegacyVim.from_nvim(nvim)
46		sys.modules['vim'] = self.legacy_vim
47
48		def setup(self, nvim):
49		"""Setup import hooks and global streams.
50
51		This will add import hooks for importing modules from runtime
52		directories and patch the sys module so 'print' calls will be
53		forwarded to Nvim.
54		"""
55		self.nvim = nvim
56		info('install import hook/path')
57		self.hook = path_hook(nvim)
58		sys.path_hooks.append(self.hook)
59		nvim.VIM_SPECIAL_PATH = '_vim_path_'
60		sys.path.append(nvim.VIM_SPECIAL_PATH)
61		info('redirect sys.stdout and sys.stderr')
62		self.saved_stdout = sys.stdout
63	5	self.saved_stderr = sys.stderr
64		sys.stdout = RedirectStream(lambda data: nvim.out_write(data))
		0 ignored issues – show Unused Code introduced 2016-03-06 13:35 UTC by Report Bug Copy Issue Report This lambda might be unnecessary. Loading history...
65		sys.stderr = RedirectStream(lambda data: nvim.err_write(data))
		0 ignored issues – show Unused Code introduced 2016-03-06 13:35 UTC by Report Bug Copy Issue Report This lambda might be unnecessary. Loading history...
66		# Setup the DirChanged listener
67		cid = nvim.channel_id
68		cmd = 'au DirChanged * call rpcrequest(%d, "python_chdir", v:event)' \
69		% cid
70		nvim.command(cmd)
71
72		def teardown(self):
73	5	"""Restore state modified from the `setup` call."""
74		nvim = self.nvim
75		info('uninstall import hook/path')
76		sys.path.remove(nvim.VIM_SPECIAL_PATH)
77		sys.path_hooks.remove(self.hook)
78		info('restore sys.stdout and sys.stderr')
79		sys.stdout = self.saved_stdout
80		sys.stderr = self.saved_stderr
81
82	5	@rpc_export('python_execute', sync=True)
83		def python_execute(self, script, range_start, range_stop):
84		"""Handle the `python` ex command."""
85		self._set_current_range(range_start, range_stop)
86		try:
87		exec(script, self.module.__dict__)
		0 ignored issues – show Coding Style Security introduced 2017-04-16 08:05 UTC by Report Bug Copy Issue Report The use of `exec` is discouraged. Execution of dynamic code might introduce security vulnerabilities. It is generally recommended to use this feature with care and only when necessary. Loading history...
88		except Exception:
89		raise ErrorResponse(format_exc_skip(1))
90
91		@rpc_export('python_execute_file', sync=True)
92		def python_execute_file(self, file_path, range_start, range_stop):
93	5	"""Handle the `pyfile` ex command."""
94		self._set_current_range(range_start, range_stop)
95		with open(file_path) as f:
96		script = compile(f.read(), file_path, 'exec')
97		try:
98		exec(script, self.module.__dict__)
		0 ignored issues – show Coding Style Security introduced 2016-06-08 19:50 UTC by Report Bug Copy Issue Report The use of `exec` is discouraged. Execution of dynamic code might introduce security vulnerabilities. It is generally recommended to use this feature with care and only when necessary. Loading history...
99		except Exception:
100		raise ErrorResponse(format_exc_skip(1))
101
102		@rpc_export('python_do_range', sync=True)
103		def python_do_range(self, start, stop, code):
104		"""Handle the `pydo` ex command."""
105		self._set_current_range(start, stop)
106		nvim = self.nvim
107		start -= 1
108		fname = '_vim_pydo'
109
110		# define the function
111		function_def = 'def %s(line, linenr):\n %s' % (fname, code,)
112		exec(function_def, self.module.__dict__)
		0 ignored issues – show Coding Style Security introduced 2016-03-06 13:35 UTC by Report Bug Copy Issue Report The use of `exec` is discouraged. Execution of dynamic code might introduce security vulnerabilities. It is generally recommended to use this feature with care and only when necessary. Loading history...
113		# get the function
114		function = self.module.__dict__[fname]
115		while start < stop:
116		# Process batches of 5000 to avoid the overhead of making multiple
117		# API calls for every line. Assuming an average line length of 100
118		# bytes, approximately 488 kilobytes will be transferred per batch,
119		# which can be done very quickly in a single API call.
120		sstart = start
121		sstop = min(start + 5000, stop)
122		lines = nvim.current.buffer.api.get_lines(sstart, sstop, True)
123
124		exception = None
125		newlines = []
126		linenr = sstart + 1
127		for i, line in enumerate(lines):
		0 ignored issues – show Unused Code introduced 2016-03-06 13:35 UTC by Report Bug Copy Issue Report The variable `i` seems to be unused. Loading history...
128		result = function(line, linenr)
129		if result is None:
130		# Update earlier lines, and skip to the next
131		if newlines:
132		end = sstart + len(newlines) - 1
133		nvim.current.buffer.api.set_lines(sstart, end,
134		True, newlines)
135		sstart += len(newlines) + 1
136		newlines = []
137		pass
		0 ignored issues – show Unused Code introduced 2016-03-06 13:35 UTC by Report Bug Copy Issue Report Unnecessary pass statement Loading history...
138		elif isinstance(result, basestring):
139		newlines.append(result)
140		else:
141		exception = TypeError('pydo should return a string ' +
142		'or None, found %s instead'
143		% result.__class__.__name__)
144		break
145		linenr += 1
146
147	5	start = sstop
148		if newlines:
149		end = sstart + len(newlines)
150		nvim.current.buffer.api.set_lines(sstart, end, True, newlines)
151		if exception:
152	5	raise exception
		0 ignored issues – show Bug introduced 2016-03-06 13:35 UTC by Report Bug Copy Issue Report Raising NoneType while only classes or instances are allowed Loading history...
153		# delete the function
154		del self.module.__dict__[fname]
155
156		@rpc_export('python_eval', sync=True)
157	5	def python_eval(self, expr):
158	5	"""Handle the `pyeval` vim function."""
159		return eval(expr, self.module.__dict__)
		0 ignored issues – show Security Best Practice introduced 2016-03-06 13:35 UTC by Report Bug Copy Issue Report `eval` should generally only be used if absolutely necessary. The usage of `eval` might allow for executing arbitrary code if a user manages to inject dynamic input. Please use this language feature with care and only when you are sure of the input. Loading history...
160
161	5	@rpc_export('python_chdir', sync=True)
162		def python_chdir(self, args):
		0 ignored issues – show Coding Style introduced 2018-01-19 11:18 UTC by Report Bug Copy Issue Report This method could be written as a function/class method. If a method does not access any attributes of the class, it could also be implemented as a function or static method. This can help improve readability. For example class Foo: def some_method(self, x, y): return x + y; could be written as class Foo: @classmethod def some_method(cls, x, y): return x + y; Loading history...
163		"""Handle working directory changes."""
164	5	os.chdir(args['cwd'])
165
166		def _set_current_range(self, start, stop):
167		current = self.legacy_vim.current
168	5	current.range = current.buffer.range(start, stop)
169	3
170
171	2	class RedirectStream(io.IOBase):
172		def __init__(self, redirect_handler):
173		self.redirect_handler = redirect_handler
174	5
175		def write(self, data):
176		self.redirect_handler(data)
177
178		def writelines(self, seq):
179		self.redirect_handler('\n'.join(seq))
180
181	5
182	5	if IS_PYTHON3:
183		num_types = (int, float)
184		else:
185		num_types = (int, long, float)
		0 ignored issues – show Comprehensibility Best Practice introduced 2016-04-08 13:03 UTC by Report Bug Copy Issue Report Undefined variable 'long' Loading history...
186
187
188	5	def num_to_str(obj):
189		if isinstance(obj, num_types):
190		return str(obj)
191		else:
192		return obj
193
194
195		class LegacyVim(Nvim):
196		def eval(self, expr):
197		obj = self.request("vim_eval", expr)
198		return walk(num_to_str, obj)
199
200
201		# This was copied/adapted from nvim-python help
202		def path_hook(nvim):
203		def _get_paths():
204		return discover_runtime_directories(nvim)
205
206		def _find_module(fullname, oldtail, path):
207		idx = oldtail.find('.')
208		if idx > 0:
209		name = oldtail[:idx]
210		tail = oldtail[idx + 1:]
211		fmr = imp.find_module(name, path)
212		module = imp.find_module(fullname[:-len(oldtail)] + name, *fmr)
213		return _find_module(fullname, tail, module.__path__)
		0 ignored issues – show Bug introduced 2016-03-06 13:35 UTC by Report Bug Copy Issue Report The Instance of `tuple` does not seem to have a member named `__path__`. This check looks for calls to members that are non-existent. These calls will fail. The member could have been renamed or removed. Loading history...
214		else:
215		return imp.find_module(fullname, path)
216
217		class VimModuleLoader(object):
218		def __init__(self, module):
219		self.module = module
220
221		def load_module(self, fullname, path=None):
		0 ignored issues – show Unused Code introduced 2016-03-06 13:35 UTC by Report Bug Copy Issue Report The argument `path` seems to be unused. Loading history...
222		# Check sys.modules, required for reload (see PEP302).
223		if fullname in sys.modules:
224		return sys.modules[fullname]
225		return imp.load_module(fullname, *self.module)
226
227		class VimPathFinder(object):
228		@staticmethod
229		def find_module(fullname, path=None):
230		"""Method for Python 2.7 and 3.3."""
231		try:
232		return VimModuleLoader(
233		_find_module(fullname, fullname, path or _get_paths()))
234		except ImportError:
235		return None
236
237	5	@staticmethod
238		def find_spec(fullname, path=None, target=None):
239		"""Method for Python 3.4+."""
240		return PathFinder.find_spec(fullname, path or _get_paths(), target)
241
242		def hook(path):
243		if path == nvim.VIM_SPECIAL_PATH:
244		return VimPathFinder
245		else:
246		raise ImportError
247
248		return hook
249
250
251		def discover_runtime_directories(nvim):
252		rv = []
253		for rtp in nvim.list_runtime_paths():
254		if not os.path.exists(rtp):
255		continue
256		for subdir in ['pythonx', PYTHON_SUBDIR]:
257		path = os.path.join(rtp, subdir)
258		if os.path.exists(path):
259		rv.append(path)
260		return rv
261

neovim / python-client

Pull Request — master (#296)

ScriptHost.python_chdir() A

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Duplication

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