This allows running `set` without triggering any event handlers.
That is useful, for example, if you want to set a variable in an event
handler for that variable - we could do it, for example, in the
fish_user_path or fish_key_bindings handlers.
This is something the `block` builtin was supposed to be for, but it
never really worked because it only allows suppressing the event for
the duration, they would fire later. See #9030.
Because it is possible to abuse this, we only have a long-option so
that people see what is up.
It's fine if it doesn't show up in the synopsis above, but putting it
under "Notes" is just too awkward.
It's a short option that exists, and so it should be documented.
I tried to make the synopsis a little less theoretical with
the placeholders and instead introduced the actual scope
options, long and short once, then refer to them as -Uflg from
then on.
I mentioned that list indicies are accepted / work to erase stuff.
In the list of options, we pretend like --unexport is long-only.
Especially with --unpath and --path, and what would go wrong
if one confused it with --univeral, and how rarely it's used,
I think it's better this way. I mention it as a synonym later
in the document so that it's not literally undocumented.
Changed phrasing such as:
"Causes the specified shell variable to be given a global scope"
Which can be read as we are taking a shell variable that exists
and giving it global scope, upgrading it to global (retaining
the value).
Redid the example section using the > syntax for things entered
into a prompt, with shell output following. The explanatory
Added in missing newlines at the ends of sentences.
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
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.
One synopsis misrenders as
set [options] VARIABLE*[*INDICES]… VALUES…
Add a missing backslash to fix that. Also go back to uppercase
because I'm not sure why this was changed to lowercase.
Finally, remove the spurious ellipsis after VARIABLE[INDICES].
This element cannot be repeated. Multiple index values and ranges
can be specified but that's already implied by the plural INDICES.
Currently,
set -q --unpath PATH
simply ignores the "--unpath" bit (and same for "--path").
This changes it, so just like exportedness you can check pathness.
* Add `set --function`
This makes the function's scope available, even inside of blocks. Outside of blocks it's the toplevel local scope.
This removes the need to declare variables locally before use, and will probably end up being the main way variables get set.
E.g.:
```fish
set -l thing
if condition
set thing one
else
set thing two
end
```
could be written as
```fish
if condition
set -f thing one
else
set -f thing two
end
```
Note: Many scripts shipped with fish use workarounds like `and`/`or`
instead of `if`, so it isn't easy to find good examples.
Also, if there isn't an else-branch in that above, just with
```fish
if condition
set -f thing one
end
```
that means something different from setting it before! Now, if
`condition` isn't true, it would use a global (or universal) variable of
te same name!
Some more interesting parts:
Because it *is* a local scope, setting a variable `-f` and
`-l` in the toplevel of a function ends up the same:
```fish
function foo2
set -l foo bar
set -f foo baz # modifies the *same* variable!
end
```
but setting it locally inside a block creates a new local variable
that shadows the function-scoped variable:
```fish
function foo3
set -f foo bar
begin
set -l foo banana
# $foo is banana
end
# $foo is bar again
end
```
This is how local variables already work. "Local" is actually "block-scoped".
Also `set --show` will only show the closest local scope, so it won't
show a shadowed function-level variable. Again, this is how local
variables already work, and could be done as a separate change.
As a fun tidbit, functions with --no-scope-shadowing can now use this to set variables in the calling function. That's probably okay given that it's already an escape hatch (but to be clear: if it turns out to problematic I reserve the right to remove it).
Fixes#565
After commit 6dd6a57c60, 3 remaining
builtins were affected by uint8_t overflow: `exit`, `return`, and
`functions --query`.
This commit:
- Moves the overflow check from `builtin_set_query` to `builtin_run`.
- Removes a conflicting int -> uint8_t conversion in `builtin_return`.
- Adds tests for the 3 remaining affected builtins.
- Simplifies the wording for the documentation for `set --query`.
- Does not change documentation for `functions --query`, because it does
not state the exit code in its API.
- Updates the CHANGELOG to reflect the change to all builtins.
builtin_set_query returns the number of missing variables. Because the
return value passed to the shell is an 8-bit unsigned integer, if the
number of missing variables is a multiple of 256, it would overflow to 0.
This commit saturates the return value at 255 if there are more than 255
missing variables.
