[READY] Move client tests to the main tests folder
This makes it possible to configure all tests at a package level by implementing the `setUpPackage` and `tearDownPackage` functions in `python/ycm/tests/__init__.py` file.
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Implement ycm_quiet_messages options (See #2021)
# 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
See issue #2021. This is a partial implementation based on the syntastic option referenced, supporting the `!` flag and filters of type `regex` and `level`. Also supports filetype specific filters using `ycm_<ft>_quiet_messages`, but I couldn't think of a great way to fall back to syntastic configs for this one.
In terms of usefulness: I've been playing with C# recently, which has a bunch of style warnings that I don't want to follow, and prefer to only have the gutter showing if there are actually errors, or warnings that I *do* want to follow.
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We eagerly compile all the filters up front, then gather the
compiled filters into a DiagnosticFilter lazily, caching the
result to avoid garbage lists.
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.
When columns are clamped to not be past the contents of the line for
highlighting diagnostics, we need to account for the column end not
being included in the diagnostic range.
