mirror of
				https://github.com/neovim/neovim.git
				synced 2025-11-04 01:34:25 +00:00 
			
		
		
		
	docs #15447
- update ":help 'hidden'" #15410 - update ":help K" #15398 - try to capture some of the debug steps from #12036 (bpftrace, USDT probes)
This commit is contained in:
		@@ -11,6 +11,7 @@ low-risk/isolated tasks:
 | 
			
		||||
- Try a [good first issue](../../labels/good-first-issue) or [complexity:low] issue.
 | 
			
		||||
- Fix bugs found by [Clang](#clang-scan-build), [PVS](#pvs-studio) or
 | 
			
		||||
  [Coverity](#coverity).
 | 
			
		||||
- [Improve documentation][wiki-contribute-help]
 | 
			
		||||
 | 
			
		||||
Reporting problems
 | 
			
		||||
------------------
 | 
			
		||||
@@ -18,17 +19,17 @@ Reporting problems
 | 
			
		||||
- [Check the FAQ][wiki-faq].
 | 
			
		||||
- [Search existing issues][github-issues] (including closed!)
 | 
			
		||||
- Update Neovim to the latest version to see if your problem persists.
 | 
			
		||||
- Disable plugins incrementally, to narrow down the cause of the issue.
 | 
			
		||||
- [Bisect](https://neovim.io/doc/user/starting.html#bisect) your config: disable plugins incrementally, to narrow down the cause of the issue.
 | 
			
		||||
- [Bisect][git-bisect] Neovim's source code to find the cause of a regression, if you can. This is _extremely_ helpful.
 | 
			
		||||
- When reporting a crash, [include a stacktrace](https://github.com/neovim/neovim/wiki/FAQ#backtrace-linux).
 | 
			
		||||
- Use [ASAN/UBSAN](#clang-sanitizers-asan-and-ubsan) to get detailed errors for segfaults and undefined behavior.
 | 
			
		||||
- [Bisect][git-bisect] to the cause of a regression, if you are able. This is _extremely_ helpful.
 | 
			
		||||
- Check `$NVIM_LOG_FILE`, if it exists.
 | 
			
		||||
- Check the logs. `:edit $NVIM_LOG_FILE`
 | 
			
		||||
- Include `cmake --system-information` for build-related issues.
 | 
			
		||||
 | 
			
		||||
Developer guidelines
 | 
			
		||||
--------------------
 | 
			
		||||
 | 
			
		||||
- Nvim contributors should read `:help dev`.
 | 
			
		||||
- Nvim developers should read `:help dev`.
 | 
			
		||||
- External UI developers should read `:help dev-ui`.
 | 
			
		||||
- API client developers should read `:help dev-api-client`.
 | 
			
		||||
- Nvim developers are _strongly encouraged_ to install `ninja` for faster builds.
 | 
			
		||||
@@ -37,13 +38,12 @@ Developer guidelines
 | 
			
		||||
  make distclean
 | 
			
		||||
  make  # Nvim build system uses ninja automatically, if available.
 | 
			
		||||
  ```
 | 
			
		||||
- [Improve documentation][wiki-contribute-help]
 | 
			
		||||
 | 
			
		||||
Pull requests (PRs)
 | 
			
		||||
---------------------
 | 
			
		||||
 | 
			
		||||
- To avoid duplicate work, create a draft pull request as soon as possible.
 | 
			
		||||
- Your PR must include **test coverage.** See [test/README.md][run-tests].
 | 
			
		||||
- To avoid duplicate work, create a draft pull request.
 | 
			
		||||
- Your PR must include [test coverage][run-tests].
 | 
			
		||||
- Avoid cosmetic changes to unrelated files in the same commit.
 | 
			
		||||
- Use a [feature branch][git-feature-branch] instead of the master branch.
 | 
			
		||||
- Use a **rebase workflow** for small PRs.
 | 
			
		||||
@@ -68,21 +68,19 @@ Pull requests have two stages: Draft and Ready for review.
 | 
			
		||||
 | 
			
		||||
1. [Create a Draft PR][pr-draft] while you are _not_ requesting feedback as
 | 
			
		||||
  you are still working on the PR.
 | 
			
		||||
    - You can skip this if your PR is ready for review.
 | 
			
		||||
2. [Change your PR to ready][pr-ready] when the PR is ready for review.
 | 
			
		||||
    - You can convert back to Draft at any time.
 | 
			
		||||
 | 
			
		||||
You can convert the state of your PR back to Draft (or Ready for review) at any
 | 
			
		||||
time. You can also skip the Draft stage if your PR is ready for review from the
 | 
			
		||||
beginning.
 | 
			
		||||
 | 
			
		||||
Do __not__ add any labels like `[RFC]` or `[WIP]` in the title to indicate the
 | 
			
		||||
Do __not__ add labels like `[RFC]` or `[WIP]` in the title to indicate the
 | 
			
		||||
state of your PR: this just adds noise. Non-Draft PRs are assumed to be open
 | 
			
		||||
for comments by default; if you want feedback from specific people, `@`-ping
 | 
			
		||||
them in a comment.
 | 
			
		||||
for comments; if you want feedback from specific people, `@`-mention them in
 | 
			
		||||
a comment.
 | 
			
		||||
 | 
			
		||||
### Commit messages
 | 
			
		||||
 | 
			
		||||
Follow the [conventional commits guidelines][conventional_commits] to *make reviews easier* and to make
 | 
			
		||||
the VCS/git logs more valuable. The general structure of a commit message is as follows:
 | 
			
		||||
the VCS/git logs more valuable. The general structure of a commit message is:
 | 
			
		||||
 | 
			
		||||
```
 | 
			
		||||
<type>([optional scope]): <description>
 | 
			
		||||
@@ -92,43 +90,27 @@ the VCS/git logs more valuable. The general structure of a commit message is as
 | 
			
		||||
[optional footer(s)]
 | 
			
		||||
```
 | 
			
		||||
 | 
			
		||||
- Prefix the commit subject with one of the following _types_:
 | 
			
		||||
    - `build`: all changes related to the build system (involving scripts, configurations or tools) and package dependencies.
 | 
			
		||||
    - `ci`: all changes related to the continuous integration and deployment system - involving scripts, configurations or tools.
 | 
			
		||||
    - `docs`: all documentation changes. This includes both external documentation for users as well as internal documentation for developers.
 | 
			
		||||
    - `feat`: new abilities or functionality.
 | 
			
		||||
    - `fix`: a bug fix.
 | 
			
		||||
    - `perf`: performance improvements.
 | 
			
		||||
    - `refactor`: modification of the code base which neither adds a feature nor fixes a bug - such as removing redundant code, simplifying code, renaming variables, etc.
 | 
			
		||||
    - `revert`: revert previous commits.
 | 
			
		||||
    - `test`: all changes related to tests such as refactoring existing tests or adding new tests.
 | 
			
		||||
    - `vim-patch`: all patches from upstream Vim. The commit messages for patches has [slightly different rules](https://github.com/neovim/neovim/wiki/Merging-patches-from-upstream-Vim#pull-requests) as not to interfere with existing scripts.
 | 
			
		||||
    - `chore`: Lastly, if none of the types above fits you may use `chore` as the type.
 | 
			
		||||
 | 
			
		||||
- Append optional scope to _type_ such as `(lsp)`, `(treesitter)`, `(float)`, ...
 | 
			
		||||
 | 
			
		||||
- The _description_ shouldn't start with a capital letter or end in a period.
 | 
			
		||||
 | 
			
		||||
- Prefix the commit subject with one of these [_types_](https://github.com/commitizen/conventional-commit-types/blob/master/index.json):
 | 
			
		||||
    - `build`, `ci`, `docs`, `feat`, `fix`, `perf`, `refactor`, `revert`, `test`, `vim-patch`, `chore`
 | 
			
		||||
    - You can **ignore this for "fixup" commits** or any commits you expect to be squashed.
 | 
			
		||||
- Append optional scope to _type_ such as `(lsp)`, `(treesitter)`, `(float)`, …
 | 
			
		||||
- _Description_ shouldn't start with a capital letter or end in a period.
 | 
			
		||||
- Use the _imperative voice_: "Fix bug" rather than "Fixed bug" or "Fixes bug."
 | 
			
		||||
- Try to keep the first line under 72 characters.
 | 
			
		||||
 | 
			
		||||
- A blank line must separate the subject from the description.
 | 
			
		||||
 | 
			
		||||
- A breaking API change must be indicated by appending `!` after the type/scope and at the very beginning of the footer with a **BREAKING CHANGE**.
 | 
			
		||||
 | 
			
		||||
- A blank line must follow the subject.
 | 
			
		||||
- Breaking API changes must be indicated by
 | 
			
		||||
    1. "!" after the type/scope, and
 | 
			
		||||
    2. a "BREAKING CHANGE" footer describing the change.
 | 
			
		||||
       Example:
 | 
			
		||||
 | 
			
		||||
       ```
 | 
			
		||||
       refactor(provider)!: drop support for Python 2
 | 
			
		||||
 | 
			
		||||
       BREAKING CHANGE: refactor to use Python 3 features since Python 2 is no longer supported.
 | 
			
		||||
       ```
 | 
			
		||||
 | 
			
		||||
- Use the _imperative voice_: "Fix bug" rather than "Fixed bug" or "Fixes bug."
 | 
			
		||||
 | 
			
		||||
### Automated builds (CI)
 | 
			
		||||
 | 
			
		||||
Each pull request must pass the automated builds on [Travis CI], [sourcehut]
 | 
			
		||||
and [AppVeyor].
 | 
			
		||||
Each pull request must pass the automated builds on [sourcehut] and [GitHub Actions].
 | 
			
		||||
 | 
			
		||||
- CI builds are compiled with [`-Werror`][gcc-warnings], so compiler warnings
 | 
			
		||||
  will fail the build.
 | 
			
		||||
@@ -282,9 +264,8 @@ as context, use the `-W` argument as well.
 | 
			
		||||
[wiki-faq]: https://github.com/neovim/neovim/wiki/FAQ
 | 
			
		||||
[review-checklist]: https://github.com/neovim/neovim/wiki/Code-review-checklist
 | 
			
		||||
[3174]: https://github.com/neovim/neovim/issues/3174
 | 
			
		||||
[Travis CI]: https://travis-ci.org/neovim/neovim
 | 
			
		||||
[sourcehut]: https://builds.sr.ht/~jmk
 | 
			
		||||
[AppVeyor]: https://ci.appveyor.com/project/neovim/neovim
 | 
			
		||||
[GitHub Actions]: https://github.com/neovim/neovim/actions
 | 
			
		||||
[Merge a Vim patch]: https://github.com/neovim/neovim/wiki/Merging-patches-from-upstream-Vim
 | 
			
		||||
[Clang report]: https://neovim.io/doc/reports/clang/
 | 
			
		||||
[complexity:low]: https://github.com/neovim/neovim/issues?q=is%3Aopen+is%3Aissue+label%3Acomplexity%3Alow
 | 
			
		||||
 
 | 
			
		||||
@@ -64,7 +64,7 @@ To install to a non-default location:
 | 
			
		||||
    make CMAKE_INSTALL_PREFIX=/full/path/
 | 
			
		||||
    make install
 | 
			
		||||
 | 
			
		||||
To inspect the build, these CMake features are useful:
 | 
			
		||||
CMake hints for inspecting the build:
 | 
			
		||||
 | 
			
		||||
- `cmake --build build --target help` lists all build targets.
 | 
			
		||||
- `build/CMakeCache.txt` (or `cmake -LAH build/`) contains the resolved values of all CMake variables.
 | 
			
		||||
 
 | 
			
		||||
@@ -46,7 +46,7 @@ NVIM IS... WELL DOCUMENTED				*design-documented*
 | 
			
		||||
  item is easier to find.
 | 
			
		||||
 | 
			
		||||
 | 
			
		||||
NVIM IS... HIGH SPEED AND SMALL IN SIZE			*design-speed-size*
 | 
			
		||||
NVIM IS... FAST AND SMALL				*design-speed-size*
 | 
			
		||||
 | 
			
		||||
Keep Nvim small and fast.
 | 
			
		||||
- Computers are becoming faster and bigger each year.  Vim can grow too, but
 | 
			
		||||
 
 | 
			
		||||
@@ -3080,17 +3080,16 @@ A jump table for the options with a short description can be found at |Q_op|.
 | 
			
		||||
				     *'hidden'* *'hid'* *'nohidden'* *'nohid'*
 | 
			
		||||
'hidden' 'hid'		boolean	(default on)
 | 
			
		||||
			global
 | 
			
		||||
	When off a buffer is unloaded when it is |abandon|ed.  When on a
 | 
			
		||||
	buffer becomes hidden when it is |abandon|ed.  If the buffer is still
 | 
			
		||||
	displayed in another window, it does not become hidden, of course.
 | 
			
		||||
	The commands that move through the buffer list sometimes make a buffer
 | 
			
		||||
	hidden although the 'hidden' option is off: When the buffer is
 | 
			
		||||
	modified, 'autowrite' is off or writing is not possible, and the '!'
 | 
			
		||||
	flag was used.  See also |windows.txt|.
 | 
			
		||||
	To only make one buffer hidden use the 'bufhidden' option.
 | 
			
		||||
	This option is set for one command with ":hide {command}" |:hide|.
 | 
			
		||||
	WARNING: It's easy to forget that you have changes in hidden buffers.
 | 
			
		||||
	Think twice when using ":q!" or ":qa!".
 | 
			
		||||
	When off a buffer is unloaded (including loss of undo information)
 | 
			
		||||
	when it is |abandon|ed.  When on a buffer becomes hidden when it is
 | 
			
		||||
	|abandon|ed.  A buffer displayed in another window does not become
 | 
			
		||||
	hidden, of course.
 | 
			
		||||
	Commands that move through the buffer list sometimes hide a buffer
 | 
			
		||||
	although the 'hidden' option is off: when the buffer is modified,
 | 
			
		||||
	'autowrite' is off or writing is not possible, and the '!' flag was
 | 
			
		||||
	used.  See also |windows|.
 | 
			
		||||
	To hide a specific buffer use the 'bufhidden' option.
 | 
			
		||||
	'hidden' is set for one command with ":hide {command}" |:hide|.
 | 
			
		||||
 | 
			
		||||
						*'history'* *'hi'*
 | 
			
		||||
'history' 'hi'		number	(Vim default: 10000, Vi default: 0)
 | 
			
		||||
 
 | 
			
		||||
@@ -460,20 +460,14 @@ defined while executing a function, user command or autocommand, the script in
 | 
			
		||||
which it was defined is reported.
 | 
			
		||||
 | 
			
		||||
							*K*
 | 
			
		||||
[count]K       		Run a program to lookup the keyword under the
 | 
			
		||||
			cursor.  The name of the program is given with the
 | 
			
		||||
			'keywordprg' (kp) option (default is "man").  The
 | 
			
		||||
			keyword is formed of letters, numbers and the
 | 
			
		||||
			characters in 'iskeyword'.  The keyword under or
 | 
			
		||||
			right of the cursor is used.  The same can be done
 | 
			
		||||
			with the command >
 | 
			
		||||
				:!{program} {keyword}
 | 
			
		||||
[count]K       		Runs the program given by 'keywordprg' to lookup the
 | 
			
		||||
			|word| (defined by 'iskeyword') under or right of the
 | 
			
		||||
			cursor. Default is "man". Works like this: >
 | 
			
		||||
				:tabnew | terminal {program} {keyword}
 | 
			
		||||
<			Special cases:
 | 
			
		||||
			- If 'keywordprg' begins with ":" it is invoked as
 | 
			
		||||
			  a Vim command with [count].
 | 
			
		||||
			- If 'keywordprg' is empty, the ":help" command is
 | 
			
		||||
			  used.  It's a good idea to include more characters
 | 
			
		||||
			  in 'iskeyword' then, to be able to find more help.
 | 
			
		||||
			- If 'keywordprg' is empty, |:help| is used.
 | 
			
		||||
			- When 'keywordprg' is equal to "man", a [count]
 | 
			
		||||
			  before "K" is inserted after the "man" command and
 | 
			
		||||
			  before the keyword.  For example, using "2K" while
 | 
			
		||||
 
 | 
			
		||||
@@ -75,8 +75,108 @@ Logs will be written to `${HOME}/logs/*san.PID` then.
 | 
			
		||||
 | 
			
		||||
For more information: https://github.com/google/sanitizers/wiki/SanitizerCommonFlags
 | 
			
		||||
 | 
			
		||||
TUI debugging
 | 
			
		||||
-------------
 | 
			
		||||
Debug: Performance
 | 
			
		||||
------------------
 | 
			
		||||
 | 
			
		||||
### Profiling (easy)
 | 
			
		||||
 | 
			
		||||
For debugging performance bottlenecks in any code, there is a simple (and very
 | 
			
		||||
effective) approach:
 | 
			
		||||
 | 
			
		||||
1. Run the slow code in a loop.
 | 
			
		||||
2. Break execution ~5 times and save the stacktrace.
 | 
			
		||||
3. The cause of the bottleneck will (almost always) appear in most of the stacktraces.
 | 
			
		||||
 | 
			
		||||
### Profiling (fancy)
 | 
			
		||||
 | 
			
		||||
For more advanced profiling, consider `perf` + `flamegraph`.
 | 
			
		||||
 | 
			
		||||
### USDT profiling (powerful)
 | 
			
		||||
 | 
			
		||||
Or you can use USDT probes via `NVIM_PROBE` ([#12036](https://github.com/neovim/neovim/pull/12036)).
 | 
			
		||||
 | 
			
		||||
> USDT is basically a way to define stable probe points in userland binaries.
 | 
			
		||||
> The benefit of bcc is the ability to define logic to go along with the probe
 | 
			
		||||
> points.
 | 
			
		||||
 | 
			
		||||
Tools:
 | 
			
		||||
- bpftrace provides an awk-like language to the kernel bytecode, BPF.
 | 
			
		||||
- BCC provides a subset of C. Provides more complex logic than bpftrace, but takes a bit more effort.
 | 
			
		||||
 | 
			
		||||
Example using bpftrace to track slow vim functions, and print out any files
 | 
			
		||||
that were opened during the trace. At the end, it prints a histogram of
 | 
			
		||||
function timing:
 | 
			
		||||
 | 
			
		||||
    #!/usr/bin/env bpftrace
 | 
			
		||||
 | 
			
		||||
    BEGIN {
 | 
			
		||||
      @depth = -1;
 | 
			
		||||
    }
 | 
			
		||||
 | 
			
		||||
    tracepoint:sched:sched_process_fork /@pidmap[args->parent_pid]/ {
 | 
			
		||||
      @pidmap[args->child_pid] = 1;
 | 
			
		||||
    }
 | 
			
		||||
 | 
			
		||||
    tracepoint:sched:sched_process_exit /@pidmap[args->pid]/ {
 | 
			
		||||
      delete(@pidmap[args->pid]);
 | 
			
		||||
    }
 | 
			
		||||
 | 
			
		||||
    usdt:build/bin/nvim:neovim:eval__call_func__entry {
 | 
			
		||||
        @pidmap[pid] = 1;
 | 
			
		||||
        @depth++;
 | 
			
		||||
        @funcentry[@depth] = nsecs;
 | 
			
		||||
    }
 | 
			
		||||
 | 
			
		||||
    usdt:build/bin/nvim:neovim:eval__call_func__return {
 | 
			
		||||
        $func = str(arg0);
 | 
			
		||||
        $msecs = (nsecs - @funcentry[@depth]) / 1000000;
 | 
			
		||||
 | 
			
		||||
        @time_histo = hist($msecs);
 | 
			
		||||
 | 
			
		||||
        if ($msecs >= 1000) {
 | 
			
		||||
          printf("%u ms for %s\n", $msecs, $func);
 | 
			
		||||
          print(@files);
 | 
			
		||||
        }
 | 
			
		||||
 | 
			
		||||
        clear(@files);
 | 
			
		||||
        delete(@funcentry[@depth]);
 | 
			
		||||
        @depth--;
 | 
			
		||||
    }
 | 
			
		||||
 | 
			
		||||
    tracepoint:syscalls:sys_enter_open,
 | 
			
		||||
    tracepoint:syscalls:sys_enter_openat {
 | 
			
		||||
      if (@pidmap[pid] == 1 && @depth >= 0) {
 | 
			
		||||
        @files[str(args->filename)] = count();
 | 
			
		||||
      }
 | 
			
		||||
    }
 | 
			
		||||
 | 
			
		||||
    END {
 | 
			
		||||
      clear(@depth);
 | 
			
		||||
    }
 | 
			
		||||
 | 
			
		||||
    $ sudo bpftrace funcslower.bt
 | 
			
		||||
    1527 ms for Slower
 | 
			
		||||
    @files[/usr/lib/libstdc++.so.6]: 2
 | 
			
		||||
    @files[/etc/fish/config.fish]: 2
 | 
			
		||||
    <snip>
 | 
			
		||||
 | 
			
		||||
    ^C
 | 
			
		||||
    @time_histo:
 | 
			
		||||
    [0]                71430 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@|
 | 
			
		||||
    [1]                  346 |                                                    |
 | 
			
		||||
    [2, 4)               208 |                                                    |
 | 
			
		||||
    [4, 8)                91 |                                                    |
 | 
			
		||||
    [8, 16)               22 |                                                    |
 | 
			
		||||
    [16, 32)              85 |                                                    |
 | 
			
		||||
    [32, 64)               7 |                                                    |
 | 
			
		||||
    [64, 128)              0 |                                                    |
 | 
			
		||||
    [128, 256)             0 |                                                    |
 | 
			
		||||
    [256, 512)             6 |                                                    |
 | 
			
		||||
    [512, 1K)              1 |                                                    |
 | 
			
		||||
    [1K, 2K)               5 |                                                    |
 | 
			
		||||
 | 
			
		||||
Debug: TUI
 | 
			
		||||
----------
 | 
			
		||||
 | 
			
		||||
### TUI troubleshoot
 | 
			
		||||
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		Reference in New Issue
	
	Block a user