It's still useful without, for instance to implement a command that
takes no options, or to check min-args or max-args.
(technically no optspecs, no min/max args and --ignore-unknown does
nothing, but that's a very specific error that we don't need to forbid)
Fixes#9006
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.
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
This matches the style in man(1) (except that we use the … ligature).
A previous iteration did the reverse (never use a space before the
ellipsis). That would be a smaller change.
Previously, when we got an unknown option with --ignore-unknown, we
would increment woptind but still try to read the same contents.
This means in e.g.
```
argparse -i h -- -ooo -h
```
The `-h` would also be skipped as an option, because after the first
`-o` getopt reads the other two `-o` and skips that many options.
This could be handled more extensively in wgetopt, but the simpler fix
is to just skip to the next argv entry once we have an unknown option
- there's nothing more we can do with it anyway!
Additionally, document this and clearly explain that we currently
don't transform the option.
Fixes#8637
Unlike links, these are checked by sphinx and it complains if they
don't match.
Also they have a better chance of doing something useful in outputs
other than html.
It was always a bit ridiculous that argparse required `X-longflag` if
that "X" short flag was never actually used anywhere.
Since the short letter is for getopt's benefit, we can hack around
this with our old friend: Unicode Private Use Areas.
We have a counter, starting at 0xE000 and going to 0xF8FF, that counts
up for all options that don't have a short flag and provides one. This
gives us up to 6400 long-only options.
6.4K should be enough for everybody.
This was written before local-exported variables did anything useful.
Passing these vars as local-exports removes the need to define the
validation function with `--no-scope-shadowing` which is quite the
hack.
