There are many applications with "primitive" argument parsing capabalities that
cannot handle munging two short options together (`-xf` for `-x -f`) or a short
option and its required value (`-dall` for `-d all`). To prevent fish from
suggesting munged arguments/payloads, the options (both long and short, not just
long!) can be specified as `-o` or `--old-option` but none of this is
documented.
This makes it so `complete -c foo -n test1 -n test2` registers *both*
conditions, and when it comes time to check the candidate, tries both,
in that order. If any fails it stops, if all succeed the completion is offered.
The reason for this is that it helps with caching - we have a
condition cache, but conditions like
```fish
test (count (commandline -opc)) -ge 2; and contains -- (commandline -opc)[2] length
test (count (commandline -opc)) -ge 2; and contains -- (commandline -opc)[2] sub
```
defeats it pretty easily, because the cache only looks at the entire
script as a string - it can't tell that the first `test` is the same
in both.
So this means we separate it into
```fish
complete -f -c string -n "test (count (commandline -opc)) -ge 2; and contains -- (commandline -opc)[2] length" -s V -l visible -d "Use the visible width, excluding escape sequences"
+complete -f -c string -n "test (count (commandline -opc)) -ge 2" -n "contains -- (commandline -opc)[2] length" -s V -l visible -d "Use the visible width, excluding escape sequences"
```
which allows the `test` to be cached.
In tests, this improves performance for the string completions by 30%
by reducing all the redundant `test` calls.
The `git` completions can also greatly benefit from this.
Includes harmonizing the display of options and arguments, standardising
terminology, using the envvar directive more broadly, adding help options to all
commands that support them, simplifying some language, and tidying up multiple
formatting issues.
string documentation is not changed.
man(1) uses lowercase placeholders but we usually don't. Additionally,
the new synopsis autoformatting only recognizes placeholders if they
are uppercase. Use uppercase for all placeholders.
Recent synopsis changes move from literal code blocks to
[RST line blocks]. This does not translate well to HTML: it's not
rendered in monospace, so aligment is lost. Additionally, we don't
get syntax highlighting in HTML, which adds differences to our code
samples which are highlighted.
We hard-wrap synopsis lines (like code blocks). To align continuation
lines in manpages we need [backslashes in weird places]. Combined with
the **, *, and `` markup, it's a bit hard to get the alignment right.
Fix these by moving synopsis sources back to code blocks and compute
HTML syntax highlighting and manpage markup with a custom Sphinx
extension.
The new Pygments lexer can tokenize a synopsis and assign the various
highlighting roles, which closely matches fish's syntax highlighing:
- command/keyword (dark blue)
- parameter (light blue)
- operator like and/or/not/&&/|| (cyan)
- grammar metacharacter (black)
For manpage output, we don't project the fish syntax highlighting
but follow the markup convention in GNU's man(1):
bold text type exactly as shown.
italic text replace with appropriate argument.
To make it easy to separate these two automatically, formalize that
(italic) placeholders must be uppercase; while all lowercase text is
interpreted literally (so rendered bold).
This makes manpages more consistent, see string-join(1) and and(1).
Implementation notes:
Since we want manpage formatting but Sphinx's Pygments highlighing
plugin does not support manpage output, add our custom "synopsis"
directive. This directive parses differently when manpage output is
specified. This means that the HTML and manpage build processes must
not share a cache, because the parsed doctrees are cached. Work around
this by using separate cache locations for build targets "sphinx-docs"
(which creates HTML) and "sphinx-manpages". A better solution would
be to only override Sphinx's ManualPageBuilder but that would take a
bit more code (ideally we could override ManualPageWriter but Sphinx
4.3.2 doesn't really support that).
---
Alternative solution: stick with line blocks but use roles like
:command: or :option: (or custom ones). While this would make it
possible to produce HTML that is consistent with code blocks (by adding
a bit of CSS), the source would look uglier and is harder to maintain.
(Let's say we want to add custom formatting to the [|] metacharacters
in HTML. This is much easier with the proposed patch.)
---
[RST line blocks]: https://docutils.sourceforge.io/docs/ref/rst/restructuredtext.html#line-blocks
[backslashes in weird places]: https://github.com/fish-shell/fish-shell/pull/8626#discussion_r782837750
Correct the grammar by moving the options after the command argument.
Also group the -c/--command and -p/--path pairs, to convey that the
short and long variants are equivalent.
While at it, consolidate the -C/--do-complete forms, like we usually
do.
Unless we use "complete --require-parameter", we must say "-w32",
not "-w 32", because the second "32" is a positional argument.
Notably, old options do not have this behavior, which is a bit weird,
see #8465
Taken from a discussion in #8459
This switch is no longer necessary when only one command is given.
Internally completions are stored separately for each command,
so we only every print one command name per "complete" line anyway.
Currently, completions have to be specified like
```fish
complete -c foo -l opt
```
while
```fish
complete foo -l opt
```
just complains about there being too many arguments.
That's kinda useless, so we just assume if there is one left-over
argument that it's meant to be the command.
Theoretically we could also use *all* the arguments as commands to
complete, but that seems unlikely to be what the user wants.
(I don't think multi-command completions really happen)
Currently only `complete` will list completions, and it will list all
of them.
That's a bit ridiculous, especially since `complete -c foo` just does nothing.
So just make `complete -c foo` list all the completions for `foo`.
