Indents added in Ubuntu and Fedora sections
# PR Prelude
Thank you for working on YCM! :)
**Please complete these steps and check these boxes (by putting an `x` inside
the brackets) _before_ filing your PR:**
- [x] I have read and understood YCM's [CONTRIBUTING][cont] document.
- [x] I have read and understood YCM's [CODE_OF_CONDUCT][code] document.
- [x] I have included tests for the changes in my PR. If not, I have included a
rationale for why I haven't.
- [x] **I understand my PR may be closed if it becomes obvious I didn't
actually perform all of these steps.**
# Why this change is necessary and useful
Indents added in Ubuntu section (for easier copy&pasting).
PS. Tests are not included - minor documentation change.
[cont]: https://github.com/Valloric/YouCompleteMe/blob/master/CONTRIBUTING.md
[code]: https://github.com/Valloric/YouCompleteMe/blob/master/CODE_OF_CONDUCT.md
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[READY] Prefer Python 3 over Python 2
When both versions are available, we should use Python 3 over Python 2 for the following reasons:
- faster startup:
<table>
<tr>
<th rowspan="2">Platform</th>
<th colspan="2">First run (ms)</th>
<th colspan="2">Subsequent runs (ms)</th>
</tr>
<tr>
<td>Python 2</td>
<td>Python 3</td>
<td>Python 2</td>
<td>Python 3</td>
</tr>
<tr>
<td>Ubuntu 16.04 64-bit</td>
<td>197</td>
<td>110</td>
<td>117</td>
<td>84</td>
</tr>
<tr>
<td>macOS 10.12</td>
<td>322</td>
<td>186</td>
<td>210</td>
<td>124</td>
</tr>
<tr>
<td>Windows 10 64-bit</td>
<td>601</td>
<td>295</td>
<td>251</td>
<td>144</td>
</tr>
</table>
*Results obtained by running the `prof.py` script from [this branch](https://github.com/micbou/YouCompleteMe/tree/profiling-startup). The difference between first run and subsequent runs is Python bytecode generation (`*.pyc` files).*
These differences are due to `python-future` monkey-patching a lot of stuff on Python 2 but not on Python 3;
- better Windows support. For instance, [the `tempfile` module returns temporary paths in all lowercase on Python 2](https://bugs.python.org/issue14255) (we use it to create our logfiles). This is fixed on Python 3.
- [Python 2 support will be dropped in 2020](https://docs.python.org/devguide/index.html#branchstatus).
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When both versions are available, we prefer Python 3 over Python 2:
- faster startup (no monkey-patching from python-future);
- better Windows support (e.g. temporary paths are not returned in all
lowercase);
- Python 2 support will eventually be dropped.
[READY] Always defer loading at VimEnter
YCM should start the same whether Vim is running in GUI or not. Otherwise, this makes it difficult for other plugins to interact with YCM at startup because they can't predict how YCM will start unless they also check if Vim is running in GUI which is unreasonable. Since we can't load it at Vim startup because of [a deadlock issue](https://github.com/Valloric/YouCompleteMe/pull/2473#issuecomment-267716136), we should always defer it at the VimEnter event.
See discussion in 39659caf34 for more details.
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[READY] Import the requests module lazily
The requests module is slow to import. See https://github.com/kennethreitz/requests/issues/3213. We should lazy load it to improve startup time. We do that by adding two methods to the `BaseRequest` class: one that returns the requests module and another the session object since it depends on the `request-futures` module and `requests-futures` imports `requests`. In addition, we make sure that no requests are sent at startup otherwise there would be no point to lazy load these. These requests would fail anyway since the server can't be ready yet.
Here are the improvements on startup time:
<table>
<tr>
<th rowspan="2">Platform</th>
<th colspan="2">First run (ms)</th>
<th colspan="2">Subsequent runs (ms)</th>
</tr>
<tr>
<td>Before</td>
<td>After</td>
<td>Before</td>
<td>After</td>
</tr>
<tr>
<td>Ubuntu 16.04 64-bit</td>
<td>240</td>
<td>131</td>
<td>173</td>
<td>74</td>
</tr>
<tr>
<td>macOS 10.12</td>
<td>435</td>
<td>315</td>
<td>261</td>
<td>208</td>
</tr>
<tr>
<td>Windows 10 64-bit</td>
<td>894</td>
<td>594</td>
<td>359</td>
<td>247</td>
</tr>
</table>
*Results obtained by running the `prof.py` script from [this branch](https://github.com/micbou/YouCompleteMe/tree/profiling-startup). The difference between first run and subsequent runs is Python bytecode generation (`*.pyc` files).*
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YCM should start the same whether Vim is running in GUI or not. Otherwise, this
makes it difficult for other plugins to interact with YCM at startup because
they can't predict how YCM will start unless they also check if Vim is running
in GUI which is unreasonable. Since we can't load it at Vim startup because of
a deadlock issue, we should always defer it at the VimEnter event.
[READY] Refactor diagnostic commands
This PR moves the logic of the `YcmDiags` and `YcmForceCompileAndDiagnostics` commands to the Python layer. It replaces the `echo` calls by `PostVimMessage` ones to display message on the status line and it always prints `Diagnostics refreshed` once compilation is done. This has the benefit of clearing the message `Forcing compilation, this will block Vim until done.` and avoiding the `Press Enter or type command to continue` prompt.
This also adds the `YcmLocationOpened` autocommand which is the same as `YcmQuickFixOpened` but for the location list window.
Fixes#2543.
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[RFC] Send requests again when server becomes ready
Since PR #2517, the `BufferVisit` and `FileReadyToParse` requests are ignored until the server is ready. We need to send them again when it becomes ready so that identifiers and snippets for the current buffer are properly parsed. This is done in the `s:OnFileReadyToParse` function since this function is regularly called. We also try to set the omnifunc since it depends on a response from the server and is only set when entering a buffer or changing its filetype. This replaces the code that consisted of setting the omnifunc when entering insert mode for the first time.
A cleaner solution would be to do that asynchronously but we can't with our Vim version requirement.
Fixes#2541.
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Don't use VimEnter initialization except when stating gui
# PR Prelude
- [x] I have read and understood YCM's [CONTRIBUTING][cont] document.
- [x] I have read and understood YCM's [CODE_OF_CONDUCT][code] document.
- [x] I have included tests for the changes in my PR. If not, I have included a
rationale for why I haven't.
- [x] **I understand my PR may be closed if it becomes obvious I didn't
actually perform all of these steps.**
# Why this change is necessary and useful
This is another attempt at:
https://github.com/Valloric/YouCompleteMe/pull/2473
Which removed the apparently flawed attempt at "lazy" loading of YCM. While it fails to get the load out of the critical startup path, it *does* serve the useful purpose when starting up gvim of avoiding a deadlock situation in gvim.
So, this time, we keep VimEnter, but only for the gui-starting case. We update the comment to explain what is actually happening. And we can keep the docs about how to defer loading.
[cont]: https://github.com/Valloric/YouCompleteMe/blob/master/CONTRIBUTING.md
[code]: https://github.com/Valloric/YouCompleteMe/blob/master/CODE_OF_CONDUCT.md
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Updated ycmd to ec7a154 to fix racerd build issues
- [x] I have read and understood YCM's [CONTRIBUTING][cont] document.
- [x] I have read and understood YCM's [CODE_OF_CONDUCT][code] document.
- [x] I have included tests for the changes in my PR. If not, I have included a
rationale for why I haven't.
- [x] **I understand my PR may be closed if it becomes obvious I didn't
actually perform all of these steps.**
# Why this change is necessary and useful
Building racerd fails with the current submodule version of ycmd. This updates ycmd to the latest commit (ec7a154 at the time of writing) and fixes racerd failing to build. No additional tests were included because this is an update a library with its own tests.
Closes#2480.
[cont]: https://github.com/Valloric/YouCompleteMe/blob/master/CONTRIBUTING.md
[code]: https://github.com/Valloric/YouCompleteMe/blob/master/CODE_OF_CONDUCT.md
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Use bang version of `normal`
Fixes#2519
# PR Prelude
Thank you for working on YCM! :)
**Please complete these steps and check these boxes (by putting an `x` inside
the brackets) _before_ filing your PR:**
- [x] I have read and understood YCM's [CONTRIBUTING][cont] document.
- [x] I have read and understood YCM's [CODE_OF_CONDUCT][code] document.
- [x] I have included tests for the changes in my PR. If not, I have included a
rationale for why I haven't.
- [x] **I understand my PR may be closed if it becomes obvious I didn't
actually perform all of these steps.**
# Why this change is necessary and useful
[Please explain **in detail** why the changes in this PR are needed.]
[cont]: https://github.com/Valloric/YouCompleteMe/blob/master/CONTRIBUTING.md
[code]: https://github.com/Valloric/YouCompleteMe/blob/master/CODE_OF_CONDUCT.md
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[READY] Remove healthy check
This PR removes the code that, if the server is not yet healthy, tries in a separate thread to send the same request at different intervals until it gets a response or reaches 5 failed attempts.
Main issue with that code is that it blocks Vim if a synchronous request (`semantic_completion_available`, `run_completer_command`, etc.) is sent while the server is not up. See issue #2071.
Other issues are that it's hard to understand how this code behaves (it combines threads and retries), it becomes useless once the server is healthy (because `SERVER_HEALTHY` is cached and never reset), it depends on arbitrary parameters (why 5 retries with a delay of 0.5s multiplied by 1.5 at each attempt?), and it has a package dependency `retries`.
Now that we catch all server exceptions (PR #2453) and define a very short connection timeout (PR #2514), we can just drop this code.
This change gives a huge improvement in startup time on Windows (don't worry, more improvements are coming for all platforms). The reason is that `requests` (probably `urllib3`) tries for ~1s to check if the server is healthy on Windows while it's almost instantaneous on other platforms.
<table>
<tr>
<th rowspan="2">Platform</th>
<th colspan="2">First run (ms)</th>
<th colspan="2">Subsequent runs (ms)</th>
</tr>
<tr>
<td>Before</td>
<td>After</td>
<td>Before</td>
<td>After</td>
</tr>
<tr>
<td>Ubuntu 16.04 64-bit</td>
<td>228</td>
<td>248</td>
<td>176</td>
<td>151</td>
</tr>
<tr>
<td>macOS 10.12</td>
<td>433</td>
<td>417</td>
<td>263</td>
<td>263</td>
</tr>
<tr>
<td>Windows 10 64-bit</td>
<td>1861</td>
<td>844</td>
<td>814</td>
<td>292</td>
</tr>
</table>
These results were obtained by running the `prof.py` script from [this branch](https://github.com/micbou/YouCompleteMe/tree/profiling-startup). The difference between first run and subsequent runs is Python bytecode generation (`*.pyc` files).
Fixes#2071.
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On non-Windows platforms, a ConnectionError exception is raised instead
of a ConnectTimeout one when the connection cannot be established (e.g.
the server crashed). Since the latter is a subclass of the former, we
only need to catch ConnectionError.
[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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[READY] Include subservers logfiles in YcmToggleLogs command
Thanks to PR #2342, we can easily update the `:YcmToggleLogs` command to also list the subservers logfiles and open them directly in Vim. For instance, when editing a Python file:
```
:YcmToggleLogs
Available logfiles are:
jedihttp_55438_stderr_g9rk18nc.log
jedihttp_55438_stdout_duc8kfqm.log
ycm_ttssiu.log
ycmd_55432_stderr_b9lnwf.log
ycmd_55432_stdout_jyakxs.log
```
Then
```
:YcmToggleLogs jedihttp_55438_stderr_g9rk18nc.log
```
to open the JediHTTP stderr logfile in Vim.
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