[READY] Rely on connect timeout instead of checking that the server is alive
Currently, we always check that the ycmd process is up (with the `IsServerAlive` method) before sending a request. Without this check, each request could block Vim until a `NewConnectionError` exception is raised if the server crashed. This is the case on Windows where it takes ~1s before the exception is raised which makes Vim unusable. However, even with this check, Vim may still be blocked in the following cases:
- the server crashes just after the check but before sending the request;
- the server is up but unresponsive (e.g. its port is closed).
To avoid both cases, we instead use [the connect timeout parameter from Requests](http://docs.python-requests.org/en/master/user/advanced/?highlight=connect%20timeout#timeouts) and set it to a duration sufficiently short (10 ms) that the blocking can't be noticed by the user. Since the server is supposed to run locally (this is what YCM is designed for), 10ms is largely enough to establish a connection.
The `IsServerAlive` check is removed almost everywhere except in `OnFileReadyToParse` because we still want to notify the user if the server crashed.
This change makes it possible to not have to [wait for the server to be healthy before sending asynchronous requests](https://github.com/Valloric/YouCompleteMe/blob/master/python/ycm/client/base_request.py#L137-L138). This will dramatically improve startup time (see issue #2085) and fixes#2071. Next PR once this one is merged.
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Vim automatically adds a space between strings when concatenating them
without the dot operator. This is not obvious so we always use the dot
operator.
Minor coding style changes when writing statements on multiple lines to
be more consistent.
Send the request as the unloaded buffer instead of the current buffer
for the BufferUnload event notification. This fixes the issue where
the filetype of the current buffer is not the same as the unloaded
buffer one, making the ycmd server uses the wrong completer when
handling the request.
Long and personal experience, when TextChangedI gets used, YCM seems
to perform better, diagnostics will trigger much less frequently at
inappropriate occasions, even less with whitespace agnostic triggers,
if I recall correctly...
When selecting candidates during completion, Vim jumps to the preview
window (if enabled) and jumps back to the actual buffer, triggering
twice the BufEnter autocommand event. This results in YCM sending
two BufferVisit and one FileReadyToParse event notifications to
ycmd, which is completely unnecessary since the current buffer
did not change. We improve this by only sending these events when the
entered buffer allowed to be completed has changed.
Open the quickfix window to full width at the bottom of the screen with
its height set to fit all entries. This behavior can be overridden by
using the YcmQuickFixOpened autocommand.
Add a new section for autocommands in the documentation.
Update GoTo and ReplaceChunks tests.
Moved File parse request handling and diagnostic extraction flow into
python to simplify flow and allow easier addition of new parse request
handlers such as semantic highlighter.
Refactored base_test to patch separate vimsupport functions instead of
the whole module, and interfering the test results afterwards.
Added new tests for diagnostic sign place/unplace and error/warning
count extraction API.
Add a new vim hook on CompleteDone. This hook is called when a
completions is selected.
When forcing semantic completion with the keybind, C# completions can
return a list of importable types. These types are from namespaces which
havn't been imported, and thus are not valid to use without also adding
their namespace's import statement. This change makes YCM automatically
insert the necessary using statement to import that namespace on
completion completion. In the case there are multiple possible
namespaces, it prompts you to choose one.
Fix the following cases where the completion is not triggered for
the next typed character:
- moving vertically in insert mode,
- removing a character and entering insert mode.
Another way in which the commit d768447 forced the client to wait for
the server to start was the UpdateDiagnosticNotifications call from the
FileReadyToParse which is called right after a buffer is loaded. In any
way if we don't have any previous FileReadyToParse request done for the
current file we bail out, so we we can wait for a FileReadyToParse
response to be available before asking if a completer is usable for the
current filetype.
ref: #1529
When we enter a new buffer we need to know if the ycmd server has a
native completer for the current filetype, this means that when we start
vim we need to know if the server has a completer available for the
buffer which means that we have to wait for the server to be up and
running. To mitigate this defer the setting of the omnifunction closer
to its need which is when we enter insert mode; this should give room
for the ycmd server to start before we ask for anything or at least
should reduce the time waiting.
ref: #1529
