Completed
Pull Request — master (#303)
by Björn
25:04
created

Nvim.close()   A

Complexity

Conditions 1

Size

Total Lines 3

Duplication

Lines 0
Ratio 0 %

Code Coverage

Tests 2
CRAP Score 1

Importance

Changes 0
Metric Value
cc 1
dl 0
loc 3
ccs 2
cts 2
cp 1
crap 1
rs 10
c 0
b 0
f 0
1
"""Main Nvim interface."""
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import os
3 5
import sys
4 5
from functools import partial
5
from contextlib import closing
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Unused Code introduced by
Unused closing imported from contextlib
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6 5
from traceback import format_stack
7
8 5
from msgpack import ExtType
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Configuration introduced by
The import msgpack could not be resolved.

This can be caused by one of the following:

1. Missing Dependencies

This error could indicate a configuration issue of Pylint. Make sure that your libraries are available by adding the necessary commands.

# .scrutinizer.yml
before_commands:
    - sudo pip install abc # Python2
    - sudo pip3 install abc # Python3
Tip: We are currently not using virtualenv to run pylint, when installing your modules make sure to use the command for the correct version.

2. Missing __init__.py files

This error could also result from missing __init__.py files in your module folders. Make sure that you place one file in each sub-folder.

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9
10 5
from .buffer import Buffer
11 5
from .common import (Remote, RemoteApi, RemoteMap, RemoteSequence,
12
                     decode_if_bytes, walk)
13 5
from .tabpage import Tabpage
14 5
from .window import Window
15 5
from ..compat import IS_PYTHON3
16 5
from ..util import Version, format_exc_skip
17
18 5
__all__ = ('Nvim')
19
20
21 5
os_chdir = os.chdir
22
23
24 5
class Nvim(object):
25
26
    """Class that represents a remote Nvim instance.
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    This class is main entry point to Nvim remote API, it is a wrapper
29
    around Session instances.
30
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    The constructor of this class must not be called directly. Instead, the
32
    `from_session` class method should be used to create the first instance
33
    from a raw `Session` instance.
34
35
    Subsequent instances for the same session can be created by calling the
36
    `with_decode` instance method to change the decoding behavior or
37
    `SubClass.from_nvim(nvim)` where `SubClass` is a subclass of `Nvim`, which
38
    is useful for having multiple `Nvim` objects that behave differently
39
    without one affecting the other.
40
    """
41
42 5
    @classmethod
43
    def from_session(cls, session):
44
        """Create a new Nvim instance for a Session instance.
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        This method must be called to create the first Nvim instance, since it
47
        queries Nvim metadata for type information and sets a SessionHook for
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        creating specialized objects from Nvim remote handles.
49
        """
50 5
        session.error_wrapper = lambda e: NvimError(e[1])
51 5
        channel_id, metadata = session.request(b'vim_get_api_info')
52
53 5
        if IS_PYTHON3:
54
            # decode all metadata strings for python3
55 5
            metadata = walk(decode_if_bytes, metadata)
56
57 5
        types = {
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            metadata['types']['Buffer']['id']: Buffer,
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            metadata['types']['Window']['id']: Window,
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            metadata['types']['Tabpage']['id']: Tabpage,
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        }
62
63 5
        return cls(session, channel_id, metadata, types)
64
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    @classmethod
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    def from_nvim(cls, nvim):
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        """Create a new Nvim instance from an existing instance."""
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        return cls(nvim._session, nvim.channel_id, nvim.metadata,
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Coding Style Best Practice introduced by
It seems like _session was declared protected and should not be accessed from this context.

Prefixing a member variable _ is usually regarded as the equivalent of declaring it with protected visibility that exists in other languages. Consequentially, such a member should only be accessed from the same class or a child class:

class MyParent:
    def __init__(self):
        self._x = 1;
        self.y = 2;

class MyChild(MyParent):
    def some_method(self):
        return self._x    # Ok, since accessed from a child class

class AnotherClass:
    def some_method(self, instance_of_my_child):
        return instance_of_my_child._x   # Would be flagged as AnotherClass is not
                                         # a child class of MyParent
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69
                   nvim.types, nvim._decode, nvim._err_cb)
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Coding Style Best Practice introduced by
It seems like _decode was declared protected and should not be accessed from this context.

Prefixing a member variable _ is usually regarded as the equivalent of declaring it with protected visibility that exists in other languages. Consequentially, such a member should only be accessed from the same class or a child class:

class MyParent:
    def __init__(self):
        self._x = 1;
        self.y = 2;

class MyChild(MyParent):
    def some_method(self):
        return self._x    # Ok, since accessed from a child class

class AnotherClass:
    def some_method(self, instance_of_my_child):
        return instance_of_my_child._x   # Would be flagged as AnotherClass is not
                                         # a child class of MyParent
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Coding Style Best Practice introduced by
It seems like _err_cb was declared protected and should not be accessed from this context.

Prefixing a member variable _ is usually regarded as the equivalent of declaring it with protected visibility that exists in other languages. Consequentially, such a member should only be accessed from the same class or a child class:

class MyParent:
    def __init__(self):
        self._x = 1;
        self.y = 2;

class MyChild(MyParent):
    def some_method(self):
        return self._x    # Ok, since accessed from a child class

class AnotherClass:
    def some_method(self, instance_of_my_child):
        return instance_of_my_child._x   # Would be flagged as AnotherClass is not
                                         # a child class of MyParent
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70
71 5
    def __init__(self, session, channel_id, metadata, types,
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                 decode=False, err_cb=None):
73
        """Initialize a new Nvim instance. This method is module-private."""
74 5
        self._session = session
75 5
        self.channel_id = channel_id
76 5
        self.metadata = metadata
77 5
        version = metadata.get("version", {"api_level": 0})
78 5
        self.version = Version(**version)
79 5
        self.types = types
80 5
        self.api = RemoteApi(self, 'nvim_')
81 5
        self.vars = RemoteMap(self, 'nvim_get_var', 'nvim_set_var')
82 5
        self.vvars = RemoteMap(self, 'nvim_get_vvar', None)
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        self.options = RemoteMap(self, 'nvim_get_option', 'nvim_set_option')
84 5
        self.buffers = Buffers(self)
85 5
        self.windows = RemoteSequence(self, 'nvim_list_wins')
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        self.tabpages = RemoteSequence(self, 'nvim_list_tabpages')
87 5
        self.current = Current(self)
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        self.session = CompatibilitySession(self)
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        self.funcs = Funcs(self)
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        self.error = NvimError
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        self._decode = decode
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        self._err_cb = err_cb
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    def _from_nvim(self, obj, decode=None):
95 5
        if decode is None:
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            decode = self._decode
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        if type(obj) is ExtType:
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            cls = self.types[obj.code]
99 5
            return cls(self, (obj.code, obj.data))
100 5
        if decode:
101 3
            obj = decode_if_bytes(obj, decode)
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        return obj
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    def _to_nvim(self, obj):
0 ignored issues
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Coding Style introduced by
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;
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105 5
        if isinstance(obj, Remote):
106 5
            return ExtType(*obj.code_data)
107 5
        return obj
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109 5
    def request(self, name, *args, **kwargs):
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        r"""Send an API request or notification to nvim.
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        It is rarely needed to call this function directly, as most API
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        functions have python wrapper functions. The `api` object can
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        be also be used to call API functions as methods:
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            vim.api.err_write('ERROR\n', async=True)
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            vim.current.buffer.api.get_mark('.')
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        is equivalent to
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            vim.request('nvim_err_write', 'ERROR\n', async=True)
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            vim.request('nvim_buf_get_mark', vim.current.buffer, '.')
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        Normally a blocking request will be sent.  If the `async` flag is
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        present and True, a asynchronous notification is sent instead. This
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        will never block, and the return value or error is ignored.
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        """
129 5
        decode = kwargs.pop('decode', self._decode)
130 5
        args = walk(self._to_nvim, args)
131 5
        res = self._session.request(name, *args, **kwargs)
132 5
        return walk(self._from_nvim, res, decode=decode)
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134 5
    def next_message(self):
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        """Block until a message(request or notification) is available.
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        If any messages were previously enqueued, return the first in queue.
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        If not, run the event loop until one is received.
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        """
140 5
        msg = self._session.next_message()
141 5
        if msg:
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            return walk(self._from_nvim, msg)
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    def run_loop(self, request_cb, notification_cb,
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                 setup_cb=None, err_cb=None):
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        """Run the event loop to receive requests and notifications from Nvim.
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        This should not be called from a plugin running in the host, which
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        already runs the loop and dispatches events to plugins.
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        """
151 5
        if err_cb is None:
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            err_cb = sys.stderr.write
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        self._err_cb = err_cb
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        def filter_request_cb(name, args):
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            name = self._from_nvim(name)
157 5
            args = walk(self._from_nvim, args)
158 5
            try:
159 5
                result = request_cb(name, args)
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            except Exception:
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                msg = ("error caught in request handler '{} {}'\n{}\n\n"
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                       .format(name, args, format_exc_skip(1)))
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                self._err_cb(msg)
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                raise
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            return walk(self._to_nvim, result)
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167 5
        def filter_notification_cb(name, args):
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            name = self._from_nvim(name)
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            args = walk(self._from_nvim, args)
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            try:
171
                notification_cb(name, args)
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            except Exception:
173
                msg = ("error caught in notification handler '{} {}'\n{}\n\n"
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                       .format(name, args, format_exc_skip(1)))
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                self._err_cb(msg)
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                raise
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        self._session.run(filter_request_cb, filter_notification_cb, setup_cb)
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180 5
    def stop_loop(self):
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        """Stop the event loop being started with `run_loop`."""
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        self._session.stop()
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184 5
    def close(self):
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        """Close the nvim session and release its resources."""
186 5
        self._session.close()
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    def __enter__(self):
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        return self
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    def __exit__(self, *exc_info):
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        self.close()
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    def with_decode(self, decode=True):
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        """Initialize a new Nvim instance."""
196
        return Nvim(self._session, self.channel_id,
197 5
                    self.metadata, self.types, decode, self._err_cb)
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    def ui_attach(self, width, height, rgb):
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        """Register as a remote UI.
201 5
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        After this method is called, the client will receive redraw
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        notifications.
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        """
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        return self.request('ui_attach', width, height, rgb)
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    def ui_detach(self):
208 5
        """Unregister as a remote UI."""
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        return self.request('ui_detach')
210 5
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    def ui_try_resize(self, width, height):
212 5
        """Notify nvim that the client window has resized.
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214 5
        If possible, nvim will send a redraw request to resize.
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        """
216 5
        return self.request('ui_try_resize', width, height)
217
218 5
    def subscribe(self, event):
219
        """Subscribe to a Nvim event."""
220 5
        return self.request('nvim_subscribe', event)
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    def unsubscribe(self, event):
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        """Unsubscribe to a Nvim event."""
224 5
        return self.request('nvim_unsubscribe', event)
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226 5
    def command(self, string, **kwargs):
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        """Execute a single ex command."""
228 5
        return self.request('nvim_command', string, **kwargs)
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    def command_output(self, string):
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        """Execute a single ex command and return the output."""
232 5
        return self.request('nvim_command_output', string)
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    def eval(self, string, **kwargs):
235
        """Evaluate a vimscript expression."""
236
        return self.request('nvim_eval', string, **kwargs)
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    def call(self, name, *args, **kwargs):
239 5
        """Call a vimscript function."""
240
        return self.request('nvim_call_function', name, args, **kwargs)
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    def strwidth(self, string):
243 5
        """Return the number of display cells `string` occupies.
244
245
        Tab is counted as one cell.
246
        """
247
        return self.request('nvim_strwidth', string)
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    def list_runtime_paths(self):
250
        """Return a list of paths contained in the 'runtimepath' option."""
251
        return self.request('nvim_list_runtime_paths')
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253
    def foreach_rtp(self, cb):
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        """Invoke `cb` for each path in 'runtimepath'.
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        Call the given callable for each path in 'runtimepath' until either
257
        callable returns something but None, the exception is raised or there
258 5
        are no longer paths. If stopped in case callable returned non-None,
259
        vim.foreach_rtp function returns the value returned by callable.
260 5
        """
261 5
        for path in self.request('nvim_list_runtime_paths'):
262
            try:
263 5
                if cb(path) is not None:
264
                    break
265
            except Exception:
0 ignored issues
show
Best Practice introduced by
Catching very general exceptions such as Exception is usually not recommended.

Generally, you would want to handle very specific errors in the exception handler. This ensure that you do not hide other types of errors which should be fixed.

So, unless you specifically plan to handle any error, consider adding a more specific exception.

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266
                break
267
268
    def chdir(self, dir_path):
269
        """Run os.chdir, then all appropriate vim stuff."""
270
        os_chdir(dir_path)
271
        return self.request('nvim_set_current_dir', dir_path)
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    def feedkeys(self, keys, options='', escape_csi=True):
274 5
        """Push `keys` to Nvim user input buffer.
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        Options can be a string with the following character flags:
277
        - 'm': Remap keys. This is default.
278
        - 'n': Do not remap keys.
279
        - 't': Handle keys as if typed; otherwise they are handled as if coming
280
               from a mapping. This matters for undo, opening folds, etc.
281
        """
282 5
        return self.request('nvim_feedkeys', keys, options, escape_csi)
283
284 5
    def input(self, bytes):
0 ignored issues
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Bug Best Practice introduced by
This seems to re-define the built-in bytes.

It is generally discouraged to redefine built-ins as this makes code very hard to read.

Loading history...
285
        """Push `bytes` to Nvim low level input buffer.
286
287
        Unlike `feedkeys()`, this uses the lowest level input buffer and the
288
        call is not deferred. It returns the number of bytes actually
289
        written(which can be less than what was requested if the buffer is
290
        full).
291
        """
292
        return self.request('nvim_input', bytes)
293
294
    def replace_termcodes(self, string, from_part=False, do_lt=True,
295
                          special=True):
296
        r"""Replace any terminal code strings by byte sequences.
297
298
        The returned sequences are Nvim's internal representation of keys,
299
        for example:
300
301 5
        <esc> -> '\x1b'
302
        <cr>  -> '\r'
303
        <c-l> -> '\x0c'
304
        <up>  -> '\x80ku'
305 5
306
        The returned sequences can be used as input to `feedkeys`.
307 2
        """
308
        return self.request('nvim_replace_termcodes', string,
309 5
                            from_part, do_lt, special)
310
311
    def out_write(self, msg, **kwargs):
312
        """Print `msg` as a normal message."""
313
        return self.request('nvim_out_write', msg, **kwargs)
314
315
    def err_write(self, msg, **kwargs):
316
        """Print `msg` as an error message."""
317
        return self.request('nvim_err_write', msg, **kwargs)
318
319
    def quit(self, quit_command='qa!'):
320
        """Send a quit command to Nvim.
321
322
        By default, the quit command is 'qa!' which will make Nvim quit without
323 5
        saving anything.
324
        """
325
        try:
326
            self.command(quit_command)
327 5
        except IOError:
0 ignored issues
show
Unused Code introduced by
This except handler seems to be unused and could be removed.

Except handlers which only contain pass and do not have an else clause can usually simply be removed:

try:
    raises_exception()
except:  # Could be removed
    pass
Loading history...
328
            # sending a quit command will raise an IOError because the
329
            # connection is closed before a response is received. Safe to
330
            # ignore it.
331
            pass
332
333
    def new_highlight_source(self):
334
        """Return new src_id for use with Buffer.add_highlight."""
335
        return self.current.buffer.add_highlight("", 0, src_id=0)
336
337 5
    def async_call(self, fn, *args, **kwargs):
338
        """Schedule `fn` to be called by the event loop soon.
339 5
340 5
        This function is thread-safe, and is the only way code not
341 5
        on the main thread could interact with nvim api objects.
342
343 1
        This function can also be called in a synchronous
344
        event handler, just before it returns, to defer execution
345
        that shouldn't block neovim.
346 1
        """
347
        call_point = ''.join(format_stack(None, 5)[:-1])
348 5
349
        def handler():
350
            try:
351 5
                fn(*args, **kwargs)
352
            except Exception as err:
353
                msg = ("error caught while executing async callback:\n"
354
                       "{!r}\n{}\n \nthe call was requested at\n{}"
355
                       .format(err, format_exc_skip(1), call_point))
356
                self._err_cb(msg)
357
                raise
358
        self._session.threadsafe_call(handler)
359
360
361
class Buffers(object):
362 5
363
    """Remote NVim buffers.
364 5
365
    Currently the interface for interacting with remote NVim buffers is the
366 5
    `nvim_list_bufs` msgpack-rpc function. Most methods fetch the list of
367
    buffers from NVim.
368 5
369
    Conforms to *python-buffers*.
370 5
    """
371
372 5
    def __init__(self, nvim):
373 5
        """Initialize a Buffers object with Nvim object `nvim`."""
374 5
        self._fetch_buffers = nvim.api.list_bufs
375
376
    def __len__(self):
377 5
        """Return the count of buffers."""
378
        return len(self._fetch_buffers())
379 5
380
    def __getitem__(self, number):
381 5
        """Return the Buffer object matching buffer number `number`."""
382
        for b in self._fetch_buffers():
383 5
            if b.number == number:
384
                return b
385
        raise KeyError(number)
386 5
387
    def __contains__(self, b):
388
        """Return whether Buffer `b` is a known valid buffer."""
389
        return isinstance(b, Buffer) and b.valid
390 5
391 5
    def __iter__(self):
392
        """Return an iterator over the list of buffers."""
393
        return iter(self._fetch_buffers())
394 5
395
396
class CompatibilitySession(object):
397
398 5
    """Helper class for API compatibility."""
399 5
400 5
    def __init__(self, nvim):
401
        self.threadsafe_call = nvim.async_call
402 5
403
404 5
class Current(object):
405
406 5
    """Helper class for emulating vim.current from python-vim."""
407
408 5
    def __init__(self, session):
409
        self._session = session
410 5
        self.range = None
411
412 5
    @property
413
    def line(self):
414 5
        return self._session.request('nvim_get_current_line')
415
416 5
    @line.setter
417
    def line(self, line):
418 5
        return self._session.request('nvim_set_current_line', line)
419
420 5
    @property
421
    def buffer(self):
422 5
        return self._session.request('nvim_get_current_buf')
423
424 5
    @buffer.setter
425
    def buffer(self, buffer):
426 5
        return self._session.request('nvim_set_current_buf', buffer)
427
428 5
    @property
429
    def window(self):
430 5
        return self._session.request('nvim_get_current_win')
431
432 5
    @window.setter
433
    def window(self, window):
434
        return self._session.request('nvim_set_current_win', window)
435 5
436
    @property
437
    def tabpage(self):
438
        return self._session.request('nvim_get_current_tabpage')
439 5
440 5
    @tabpage.setter
441
    def tabpage(self, tabpage):
442 5
        return self._session.request('nvim_set_current_tabpage', tabpage)
443 5
444
445
class Funcs(object):
446 5
447 5
    """Helper class for functional vimscript interface."""
448
449
    def __init__(self, nvim):
450
        self._nvim = nvim
451
452
    def __getattr__(self, name):
453
        return partial(self._nvim.call, name)
454
455
456
class NvimError(Exception):
457
    pass
458