[READY] Java support with asynchronous diagnostics and messages
# 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
This change is required for a better user experience when using native
java support
This implements an asynchronous message system using a long-poll request
to the server.
The server provides an endpoint /receive_messages which blocks until
either a timeout occurs or we receive a batch of asynchronous messages.
We send this request asynchronously and poll it 4 times a second to see
if we have received any messages.
The messages may either be simply for display (such as startup progress)
or diagnostics, which override the diagnostics returned by
OnFileReqdyToParse.
In the former case, we simply display the message, accepting that this
might be overwritten by any other message (indeed, requiring this), and
for the latter we fan out diagnostics to any open buffer for the file in
question.
Unfortunately, Vim has bugs related to timers when there is something
displayed (such as a "confirm" prompt or other), so we suspend
background timers when doing subcommands to avoid vim bugs. NOTE: This
requires a new version of Vim (detected by the presence of the
particular functions used).
NOT_READY because:
- the submodule commit points at my repo and requires https://github.com/Valloric/ycmd/pull/857 to be merged
- my spider sense suggest i have more testing to do...
Notes:
- Part 3 (I think) of the Java support PRs. This one actually adds the minimal changes for working java support
- There are about 2 or 3 other PRs to come to add things like automatic module imports, etc.
[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
<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/valloric/youcompleteme/2863)
<!-- Reviewable:end -->
This implements an asynchronous message system using a long-poll request
to the server.
The server provides an endpoint /receive_messages which blocks until
either a timeout occurs or we receive a batch of asynchronous messages.
We send this request asynchronously and poll it 4 times a second to see
if we have received any messages.
The messages may either be simply for display (such as startup progress)
or diagnostics, which override the diagnostics returned by
OnFileReqdyToParse.
In the former case, we simply display the message, accepting that this
might be overwritten by any other message (indeed, requiring this), and
for the latter we fan out diagnostics to any open buffer for the file in
question.
Unfortunately, Vim has bugs related to timers when there is something
displayed (such as a "confirm" prompt or other), so we suspend
background timers when doing subcommands to avoid vim bugs. NOTE: This
requires a new version of Vim (detected by the presence of the
particular functions used).
Evaluating the values of g:ycm_extra_conf_vim_data may raise a Python exception
(e.g. one of the values is not defined). Since that option is parsed each time
a request is sent, such exception makes the editor almost unusable as each key
press is printing a Python traceback to the user. Catch and log the exception.
Reduce the time spent to build the request when there are a lot of buffers by:
- using the options property on the buffer object to get the mod variable
instead of evaluating getbufvar;
- not computing the buffer filepath if the buffer is not modified;
- passing the number of the unloaded buffer instead of its filepath on the
BufferUnload event. Getting the Python buffer object from its number is
easier than from its filepath.
[READY] Always supply working directory
This allows completer servers to detect the correct directory to launch
no matter what request initialises the completer server.
# 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
This change ensures that the client supplies the working directory to the server on each request, in particular, event notifications; the java and javascript completers use this to start the server in the `FileReadyToParse` event, rather than on construction of the completer. The subtle difference allows them to use the client's working directory, rather than the _server's_ working directory to do things like project detection.
See also:
* This is PR 1 of the set of changes related to #2827 - client changes required to support Java and other language-server protocols.
* ycmd change for javascript that makes use of this now: https://github.com/Valloric/ycmd/pull/886
* updated API doc: http://puremourning.github.io/ycmd-1
The ycmd API change is simply to allow `working_dir` on all requests.
cc for minor optional API change: @abingham @Qusic @LuckyGeck @mawww @richard1122 @jakeanq @orsonteodoro
[cont]: https://github.com/Valloric/YouCompleteMe/blob/master/CONTRIBUTING.md
[code]: https://github.com/Valloric/YouCompleteMe/blob/master/CODE_OF_CONDUCT.md
<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/valloric/youcompleteme/2861)
<!-- Reviewable:end -->
When no argument is given to the YcmToggleLogs command, instead of displaying
the list of available logfiles, prompt the user to open (or close if already
open) one of them.
On Windows, the options file cannot be deleted while it is still open by
another process. Close the file before starting the server. Do not explicitly
flush the file as closing implies flushing.
Bring fully asynchronous completion by polling for completions with a timer
then calling completefunc once the completions are ready. Use the start column
returned by the server in completefunc. Immediately display the last completion
on the TextChangedI event to prevent the popup menu disappearing while waiting
for the completions. Handle the TextChangedI event not being triggered while
the completion menu is open by closing the menu when inserting a character
through the InsertCharPre event, and when deleting a character on the <BS> and
<C-h> keys.
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.
When an error occurs during completions, a message is displayed on
the status line. If this message is longer than the width of the
current window, Vim will prompt the user to press enter or type a
command to hide the message, interrupting user workflow. We prevent
that by truncating the message to window width.
Merge PostMultiLineNotice, EchoText, and EchoTextVimWidth functions
into PostVimMessage.
Display an error message to the user depending on the status code
returned by the ycmd server.
Remove ycm_core checks in plugin/youcompleteme.vim. These checks are
now done by the ycmd server.
Do not start a separate process to check the core version but rely on
ycmd returning a specific exit code. This slightly improves the Vim
startup time.
Do not send an "event_notification" request in OnFileReadyToParse
function if server process is terminated. Otherwise, it blocks Vim
for one second or results in a traceback each time the InsertLeave,
CursorMoved, CursorHold, and BufferVisit events are triggered.
